CN101902060A - Charge-discharge battery pack equilibrium management system - Google Patents

Abstract

The invention discloses a charge-discharge battery pack equilibrium management system which comprises N batteries, N-1 lossless equilibrium charge-discharge circuits, a signal acquisition circuit, a master control unit and a drive circuit, wherein each lossless equilibrium charge-discharge circuit comprises an energy storage inductor, an energy storage capacitor, a first semiconductor switch device and a second semiconductor switch device and is characterized in that the energy storage capacitor is connected in series between a switch back end of the first semiconductor switch device and a switch front end of the second semiconductor switch device. The charge-discharge battery pack equilibrium management system has the obvious effects that the capacitor in the equilibrium mode plays a role of energy transfer, which reduces the power consumption, has more advantages in volume and weight, and has stronger mechanical impact resistance. The charge-discharge battery pack equilibrium management system realizes the energy equilibrium of batteries, dispensing with a complicated energy transfer device, and has the advantages of simple structure, easy realization and convenient maintenance and expansion.

Description

Charge-discharge battery pack equilibrium management system

Technical field

The present invention relates to a kind of circuit that is used for extensive lithium battery group management of charging and discharging, particularly relate to a kind of management circuit that is used for the electric power system of electric automobile, and relate to a kind of charge-discharge battery pack equilibrium management system with fault-proof circuit.

Background technology

Along with petering out of petroleum resources, the increase day by day of ambient pressure replaces traditional fossil fuel with electric energy, and the cry that makes it to become automobile-used major impetus source grows with each passing day.In addition, along with the development of the novel electron instrument and equipments such as synchronous satellite of the earth satellite of progress, notebook computer, microcomputer, digital camera, mobile phone, medical equipment and the near-earth orbit of science and technology and high orbit, battery industry is had higher requirement.Low cost, high-energy-density, high voltage, lightness, serviceability temperature is wide, has extended cycle life, and brand-new green battery, particularly rechargeable secondary cell that security performance is good---lithium battery enjoys people to pay close attention to.

But powerful again lithium ion battery also has a moment of depleted of energy, has only with charger perfectly to cooperate its competence exertion maximum capacity.So in today that lithium ion battery yields unusually brilliant results, the charger chip has also obtained increasing concern.And the correctness of battery charging process will directly influence the performance and the life-span of battery.Existing lithium battery charger exists problems and deficiency, as the scope of application of charging is little, charging interval is long, and efficient is low and charging modes is single, do not support the task dispatching to batteries charging, particularly can not realize when the polylith battery charged simultaneously the balancing energy to battery pack.

Lithium battery and NI-G, Ni-MH battery are not quite alike, must consider when using it to charge, the fail safe when discharging, and to prevent deterioration in characteristics, battery are caused expendable breaking-up.Therefore lithium battery charger is required very high, also to have corresponding protection components and parts or protective circuit guarantee cell safety, reliably, charging promptly.Because it is different that the capacity difference (representing with mAh or Ah) of the rechargeable battery of various chemical analysis, output voltage difference, charging process require, need different chargers to satisfy its different requirement.Therefore each semiconductor manufacturer develops multiple charger IC, and the charger IC that some big semiconductor manufacturers produce has tens kinds more than, and also constantly releasing various New-type charge device IC to satisfy the needs in market every year.At present China lithium battery charger enterprise is numerous, but technical merit, quality level are uneven, and the core technology majority is grasped semiconductor manufacturer abroad.

In addition, along with the continuous development of integrated circuit and the continuous increase in secondary cell market, the exhaustion of the energy, the main equipment that the environmental protection of lithium battery and the advantage of high-energy-density are applied to as automobile the multisection lithium battery series connection is no longer a dream, that is to say that jumbo lithium battery charging system will be widely used, must relate to serial connection charge Study on Technology so multiple batteries.So design, produce high-quality, high efficiency, meet the IC that discharges and recharges of instructions for use, particularly release and to realize that the IC of battery pack power equilibrium has crucial meaning.Therefore, the development of novel quick lithium battery group management of charging and discharging system be developed to for inevitable.

As shown in Figure 5: occurred a kind of balanced management circuit that discharges and recharges battery pack at present, each balanced management circuit comprises energy storage inductor, first semiconductor switching device and second semiconductor switching device;

The positive pole of prime battery in adjacent two batteries of termination behind the switch of first semiconductor switching device wherein, connect the negative pole of prime battery behind the described energy storage inductor of switch front end string, the switch front end of this first semiconductor switching device also connects the positive pole of first diode, and the negative pole of this first diode connects the switch rear end of first semiconductor switching device;

Wherein the switch rear end of second semiconductor switching device is connected with the switch front end of described first semiconductor switching device, the switch front end of second semiconductor switching device connects the negative pole of level battery in back in adjacent two batteries, the switch front end of this second semiconductor switching device also connects the positive pole of second diode, and the negative pole of this second diode connects the switch rear end of second semiconductor switching device;

This is a kind of two-way non-dissipative equalizing charging scheme, and each battery balanced shunt circuit is formed by two semiconductor switching devices, two diodes and an energy-storage travelling wave tube inductance.Circuit during polylith battery polyphone connects situation.During charging, suppose that the appearance of two cell voltages is unbalanced in equalizing circuit, as V _B1＞V _B2, the then other semiconductor switching device Q11 conducting of first segment battery B1, the first segment battery is to inductance L 1 charging, when Q11 ended, L1 constituted the loop for afterflow with the second batteries B2, the second diode D12, energy stored is just transferred among the B2 in the inductance, has realized the transfer of energy from B1 to B2.Together should V _B2＞V _B1The time, then the break-make by Q12 realizes the transfer of energy from B2 to B1, promptly this circuit is a kind of balancer of energy bi-directional.Although energy only transmits between adjacent cell, always owing to the transmission trend of energy is delivered on the low battery of voltage by the high battery of voltage, thereby the final equilibrium that realizes whole Battery pack.Mathematics model analysis is as follows, and the current waveform on the L1 as shown in Figure 6.

Work as Q ₁₁(t during conducting ₀≤ t＜t ₁), have as shown in the formula establishment:

${\mathrm{<figure-callout\; id="1"\; label="V\; B"\; filenames="HSA00000203340700011.png,HSA00000203340700012.png"\; state="\{\{state\}\}">V</figure-callout>}}_B={\mathrm{<figure-callout\; id="1"\; label="L"\; filenames="HSA00000203340700011.png,HSA00000203340700012.png"\; state="\{\{state\}\}">L</figure-callout>}}_1\frac{{\mathrm{di}}_{\mathrm{<figure-callout\; id="1"\; label="L"\; filenames="HSA00000203340700011.png,HSA00000203340700012.png"\; state="\{\{state\}\}">L</figure-callout>}1}}{\mathrm{dt}},$ i _L1(t ₀)＝0 (1)

${\mathrm{<figure-callout\; id="1"\; label="I\; L"\; filenames="HSA00000203340700011.png,HSA00000203340700012.png"\; state="\{\{state\}\}">I</figure-callout>}}_L=\frac{V_{B1}}{L_1}t---\left(2\right)$

Work as Q ₁₁Turn-off D ₁₂(t when being forced to conducting ₁≤ t＜t ₂), have as shown in the formula establishment:

${\mathrm{<figure-callout\; id="2"\; label="V\; B"\; filenames="HSA00000203340700011.png,HSA00000203340700012.png"\; state="\{\{state\}\}">V</figure-callout>}}_B={\mathrm{<figure-callout\; id="1"\; label="L"\; filenames="HSA00000203340700011.png,HSA00000203340700012.png"\; state="\{\{state\}\}">L</figure-callout>}}_1\frac{{\mathrm{di}}_{\mathrm{<figure-callout\; id="1"\; label="L"\; filenames="HSA00000203340700011.png,HSA00000203340700012.png"\; state="\{\{state\}\}">L</figure-callout>}1}}{\mathrm{dt}},$ i _L1(t ₁)＝I _L (3)

Suppose Q ₁A switch periods be T _S, D is Q ₁The ratio of ON time and switch periods, i.e. duty ratio.As set euqalizing current, i.e. electric current I on the inductance _P, then obtain by above formula:

$I_P=\frac{V_{B1}}{L_1}{T}_{S}D---\left(4\right)$

Can release:

$T_S=\frac{I_P{L}_1}{V_{B1}D}---\left(5\right)$

Thereby the PWM frequency that can obtain switch (MOSFET) is:

$f=\frac{1}{T_S}---\left(11\right)$

Work as V _B2＞V _B1The time, same earlier with Q ₂₁Q is turn-offed in conducting again after a period of time ₂₁, this moment D ₁₁Be forced to conducting, thereby realized that energy is from B ₂To B ₁Transfer.

The shortcoming of this balanced management circuit is: just shift energy with inductance, thus must increase substantially inductance value as increasing efficient, and because the restriction of the manufacture craft of inductance, its equivalent resistance causes power loss bigger more greatly.Though inductance can accomplish to flow through big electric current, inductance has magnetically saturated problem, when frequency is lower than the natural frequency of inductance, can cause that electric current is huge to be increased, and light is that power consumption increases, and the power component in the circuit is burnt in serious meeting.Its volume weight also is a not too dominant place in addition, and magnetic core also is afraid of to fall.And experimental results show that its efficient is lower, generally do not reach 40%, so this scheme and be not suitable for actual application.

Summary of the invention

The invention provides a kind of charge-discharge battery pack equilibrium management system of suitable practical application needs, it is low in energy consumption, simple in structure, volume is little, in light weight, efficient is very high.

Technical scheme of the present invention is as follows: a kind of charge-discharge battery pack equilibrium management system, comprise N battery and N-1 non-dissipative equalizing charge-discharge circuit, N battery strings composition battery pack that is connected together, every adjacent two batteries are connected with same non-dissipative equalizing charge-discharge circuit in the battery pack;

Signal acquisition circuit: voltage, temperature and the charging and discharging currents of gathering every batteries in the battery pack;

Main control unit: control the work schedule of described signal acquisition circuit, obtain the magnitude of voltage, current value and the temperature value that collect, the work schedule of 2N-2 drive circuit of control;

Drive circuit: the operating state of a non-dissipative equalizing charge-discharge circuit of per two drive circuits control; Described non-dissipative equalizing charge-discharge circuit comprises energy storage inductor, first semiconductor switching device and second semiconductor switching device;

The positive pole of prime battery in described adjacent two batteries of termination behind the switch of first semiconductor switching device wherein, connect the negative pole of prime battery behind the described energy storage inductor of switch front end string, the switch front end of this first semiconductor switching device also connects the positive pole of first diode, and the negative pole of this first diode connects the switch rear end of first semiconductor switching device;

Wherein the switch rear end of second semiconductor switching device is connected with the switch front end of described first semiconductor switching device, the switch front end of second semiconductor switching device connects the negative pole of level battery in back in adjacent two batteries, the switch front end of this second semiconductor switching device also connects the positive pole of second diode, and the negative pole of this second diode connects the switch rear end of second semiconductor switching device;

The control end of described first semiconductor switching device and second semiconductor switching device is connected on respectively on the output of first drive circuit and second drive circuit;

Because at this semiconductor switching device of using is to float ground, so the switch front end of described first semiconductor switching device and second semiconductor switching device is connected on respectively on the input of first drive circuit and second drive circuit;

Its key is: be serially connected with storage capacitor between the switch rear end of described first semiconductor switching device and the switch front end of second semiconductor switching device.First semiconductor switching device, second semiconductor switching device, storage capacitor and energy storage inductor are formed a non-dissipative equalizing module.

Balanced way electric capacity of the present invention has played the main effect that energy shifts, and it mainly is to shift electric capacity by energy to realize that the energy between two batteries shifts, rather than inductance, so that inductance value do not need is too big, thereby reduces power consumption.The advantage of comparing capacitance energy storage with inductive energy storage is to be full of almost no longer power consumption behind the electricity, and own loss is less, and volume and weight also has greater advantage, and anti-mechanical impact property is stronger.And the voltage of energy transfer electric capacity is constant substantially among the present invention, so consumed energy hardly, efficient is very high, experimental results show that its efficient can reach 80%, therefore the present invention had both satisfied the harmless basic demand of energy, realize the balancing energy of battery, do not had to use complicated energy converter device again.Simple in structure, realize easily and maintenance and expansion convenient.

Described signal acquisition circuit is provided with own decoder group, the first input end of each decoder and second input are connected on the described main control unit gating control end through bus in this decoder group, the output group of decoder is connected on the input of relay group, the collection terminal group of relay group is connected with described battery pack, the output group of relay group is connected with 1 difference amplification and absolute value treatment circuit in the mode of bus, and described difference is amplified and the output of absolute value treatment circuit is connected on the data input pin of described main control unit.

Before the strategy of decision equilibrium, need to detect in real time every batteries both end voltage.In order effectively to isolate each cell voltage analog input channel, adopt the AQW214 Photo-MOS of Panasonic relay as multiplexer, select 4 decoder 74LS139 to control the conducting of AQW214 relay with 2.The cell voltage routing inspection circuit is equipped with this relay for each cell, when needs detect the voltage of a certain batteries, only need open corresponding relay.Each cell both end voltage that collects sent into difference is amplified modulate circuit and absolute value circuit is sampled, obtain the cell terminal voltage, send into the built-in AD converter conversion of main control unit then.Per 3 AQW214 relays and 1 74LS139 decoder can detect 5 batteries.

1 74LS139 has two decoders, and the first input end of two decoders and second input are connected main control unit through bus, and the output winding of two decoders is on 3 AQW214 relays.

The first input end of the first output termination, first relay of first decoder;

The first input end of the second output termination, second relay of first decoder;

The first input end of the 3rd output termination the 3rd relay of first decoder;

Second input of the first output termination, first relay of second decoder;

Second input of the second output termination, second relay of second decoder;

Second input of the 3rd output termination the 3rd relay of second decoder;

The positive pole of one termination, the first battery B1 of first relay, first switch, the first input end of another termination difference channel of first relay, first switch;

One end of the first relay second switch connects the negative pole of the first battery B1 and the positive pole of the second battery B2, second input of another termination difference channel of the first relay second switch simultaneously; The output termination of difference channel is amplified the input of follow circuit, amplifies the input of the output termination absolute value circuit of follow circuit, the output termination main control unit of absolute value circuit.

One end of second relay, first switch connects the negative pole of the second battery B2 and the positive pole of the 3rd battery B3 simultaneously, the first input end of another termination difference channel of second relay, first switch;

One end of the second relay second switch connects the negative pole of the 3rd battery B3 and the positive pole of the 4th battery B4, second input of another termination difference channel of the second relay second switch simultaneously; The output termination of difference channel is amplified the input of follow circuit, amplifies the input of the output termination absolute value circuit of follow circuit, the output termination main control unit of absolute value circuit.

One end of the 3rd relay first switch connects the negative pole of the 4th battery B4 and the positive pole of the 5th battery B5 simultaneously, the first input end of another termination difference channel of the 3rd relay first switch;

One end of the 3rd relay second switch connects the negative pole of the 5th battery B5 and the positive pole of the 6th battery B6, second input of another termination difference channel of the 3rd relay second switch simultaneously; The output termination of difference channel is amplified the input of follow circuit, amplifies the input of the output termination absolute value circuit of follow circuit, the output termination main control unit of absolute value circuit.

And the like, can be connected in series unlimited decoder and relay, and all connect difference and amplify modulate circuit and absolute value circuit in the mode of bus, the output that then difference is amplified modulate circuit and absolute value circuit is connected on the input interface of main control unit.

The drive controlling end group of described main control unit is connected with 2N-2 Drive and Control Circuit, each Drive and Control Circuit is provided with the prime reverser, the input of this prime reverser connects described main control unit, output is after first light-coupled isolation, be connected the input of back level reverser, the output of back level reverser is connected the input of MOSFET drive controlling chip, and the output of MOSFET drive controlling chip connects first semiconductor switching device or second semiconductor switching device in the described drive circuit.

That the present invention adopts is the special-purpose MOSFET drive controlling chip I R2103 that American I R company produces, it is a kind of binary channels high pressure, high speed voltage-type device for power switching gate drivers, have independently high-end and the low side output channel, the power supply of floating adopts boostrap circuit, its high-end operating voltage can reach 600V, the gate drive voltage scope of output is 10～20V, logic supply voltage scope 5～15V.Satisfy the demand of design fully.IO mouth by main control unit produces square wave earlier, through digital light-coupled isolation, receives IR2103 and MOSFET.Application circuit as shown in figure 11,12V is fixing power supply, C26 is a bootstrap capacitor, power supply charges to C26 through D11, load, MOSFET, the grid of MOSFETI pipe drives by enough energy storage on the C26.Consider that it is the reliable key that drives that bootstrap capacitor C26 stablizes quick charge, and the desired switching frequency of native system is about 10KHz, so the Capacity Selection of C26 is less than 10uF.

As shown in figure 11, the control end of described first semiconductor switching device of output termination of MOSFET drive controlling chip, the switch front end of input termination first semiconductor switching device, thereby the driving of floating ground of realization semiconductor switching device.

The positive pole of the first batteries of described battery pack connects the stiff end of diverter switch, and first movable end of this diverter switch is acted in collusion to make each other's confessions and connect the negative pole of described battery pack minor details battery behind the power supply;

Connect the negative pole of described battery pack minor details battery after the second movable end string load of described diverter switch.

The charging control end of described main control unit also is connected with charging control circuit, and this charging control circuit is serially connected between described power supply and the first batteries of battery pack;

Described charging control circuit is provided with second optocoupler, the positive input of this second optocoupler connects positive supply, negative input connects described main control unit, the negative sense output head grounding of second optocoupler, the grid of forward output termination switching tube, the source electrode of this switching tube connects described power supply, drain electrode connects the front end of stabilizing inducatnce, ground connection behind the rear end string electric capacity of voltage regulation of stabilizing inducatnce, also order is to the positive pole of diode in the rear end of this voltage stabilizing inductance, and the negative pole of this unilateral diode connects first movable end of described diverter switch.

Charging control circuit adopts pulse-width modulation (PWM) mode to control the size of supply current.The PWM ripple is controlled its increase or is reduced pulsewidth by the PWM mouth output of main control unit.Pwm signal is by the MOSFET on the photoelectricity isolation drive major loop.Switching tube, diode, lc circuit constitute switching power supply.The Switching Power Supply of controlling with the PWM mode can reduce power consumption, is convenient to carry out Digital Control simultaneously.

Be serially connected with Hall current sensor between described battery pack and diverter switch, the output of this Hall element connects the voltage acquisition input of described main control unit.

Each battery is other in described battery pack is fixed with temperature sensor, and the output of described temperature sensor is connected on the temperature input port of described main control unit through bus.

The invention has the beneficial effects as follows: balanced way electric capacity of the present invention has played the main effect that energy shifts, it mainly is to shift electric capacity by energy to realize that energy between two batteries shifts, rather than inductance, so that inductance value does not need is too big, thereby reduce power consumption.The advantage of comparing capacitance energy storage with inductive energy storage is to be full of almost no longer power consumption behind the electricity, and own loss is less, and volume and weight also has greater advantage, and anti-mechanical impact property is stronger.And the voltage of energy transfer electric capacity is constant substantially among the present invention, so consumed energy hardly, efficient is very high, experimental results show that its efficient can reach 80%, therefore the present invention had both satisfied the harmless basic demand of energy, realize the balancing energy of battery, do not had to use complicated energy converter device again.Simple in structure, realize easily and maintenance and expansion convenient.

The present invention

1. finish the balancing energy of battery in the time of not only can charging to many batteries simultaneously, can also carry out the non-dissipative equalizing of energy at discharge process, can solve overcharging and cross and putting problem of existence in the battery series-connection charge-discharge effectively, prolong the useful life of battery pack greatly.

2. can show the state that discharges and recharges in real time and detect the temperature of battery.The current voltage and the charging and discharging currents that can on LCD, show battery, accurately directly perceived.And the temperature of changeable demonstration battery, prevent excess temperature, damage battery.

3. built-in safeguard protection device, power supply or battery connects instead no matter, charger is not all worked, and guarantees that charger and battery all do not suffer damage.

Description of drawings

The present invention is further described below in conjunction with drawings and Examples.

Fig. 1 system architecture diagram of the present invention

Fig. 2 battery pack balancing structure chart of the present invention

The signal acquisition circuit that Fig. 3 monomer battery voltage of the present invention and charging and discharging currents are patrolled and examined

Fig. 4 PWM charging control circuit of the present invention

Use the two-way non-dissipative equalizing circuit of inductance in Fig. 5 prior art as energy storage

Fig. 6 prior art V _B1＞V _B2The time Q ₁₁Conducting is turn-offed, L ₁Last electrorheological waveform

Fig. 7 the present invention two-way non-dissipative equalizing circuit of electric capacity as energy storage

The flow graph of electric current during Fig. 8 non-dissipative equalizing of the present invention

Fig. 9 V of the present invention _B1＞V _B2The time Q ₁Conducting is turn-offed, L ₁And C ₁Last voltage and electric current change waveform

Figure 10 MOSFET Drive and Control Circuit

Embodiment

As shown in Figure 1, 2, the present invention is a kind of charge-discharge battery pack equilibrium management system, comprise N battery and N-1 non-dissipative equalizing charge-discharge circuit 1, N battery strings composition battery pack that is connected together, every adjacent two batteries are connected with same non-dissipative equalizing charge-discharge circuit 1 in the battery pack;

Signal acquisition circuit 2: voltage, temperature and the charging and discharging currents of gathering every batteries in the battery pack;

Main control unit 3: control the work schedule of described signal acquisition circuit 2, obtain the magnitude of voltage, current value and the temperature value that collect, the work schedule of 2N-2 drive circuit 4 of control; Output pwm signal is with the break-make of control charging control circuit 5; Finish control to LCD and function button;

As shown in Figure 7, drive circuit 4: the operating state of a non-dissipative equalizing charge-discharge circuit 1 of per two drive circuits, 4 controls; Described non-dissipative equalizing charge-discharge circuit 1 comprises energy storage inductor L1 and storage capacitor C1, the first semiconductor switching device Q1 and the second semiconductor switching device Q2;

The positive pole of prime battery in described adjacent two batteries of termination behind the switch of the first semiconductor switching device Q1 wherein, connect the negative pole of prime battery behind the described energy storage inductor L1 of switch front end string, the switch front end of this first semiconductor switching device Q1 also connects the positive pole of the first diode D1, and the negative pole of this first diode D1 connects the switch rear end of the first semiconductor switching device Q1;

Wherein the switch rear end of the second semiconductor switching device Q2 is connected with the switch front end of the described first semiconductor switching device Q1, the switch front end of the second semiconductor switching device Q2 connects the negative pole of level battery in back in adjacent two batteries, the switch front end of this second semiconductor switching device Q2 also connects the positive pole of the second diode D2, and the negative pole of this second diode D2 connects the switch rear end of the second semiconductor switching device Q2;

The control end of the described first semiconductor switching device Q1 and the second semiconductor switching device Q2 is connected on respectively on the output VQ1 of first drive circuit and second drive circuit;

Because at this semiconductor switching device of using is to float ground, so on the VQ1 and VQG1 end that the control end of the described first semiconductor switching device Q1 and the second semiconductor switching device Q2 and switch front end are connected on drive circuit 4 respectively;

Because at this semiconductor switching device of using is to float ground, so the switch front end of the described first semiconductor switching device Q1 and the second semiconductor switching device Q2 is connected on respectively on the input VQG1 of first drive circuit and second drive circuit;

Its key is: be serially connected with storage capacitor C1 between the switch front end of the switch rear end of the described first semiconductor switching device Q1 and the second semiconductor switching device Q2.

Semiconductor switching device can be the electronic switching device that field effect transistor, triode, IGBT etc. possess switching function.As field effect transistor, its grid can be used as the control end of semiconductor switching device, and its source electrode can be used as the switch front end, and drain electrode can be used as the switch rear end.

As shown in Figure 8, balanced way electric capacity of the present invention has played the main effect that energy shifts, and it mainly is to shift electric capacity by energy to realize that the energy between two batteries shifts, rather than inductance, so that inductance value do not need is too big, thereby reduces power consumption.The advantage of comparing capacitance energy storage with inductive energy storage is to be full of almost no longer power consumption behind the electricity, and own loss is less, and volume and weight also has greater advantage, and anti-mechanical impact property is stronger.And the voltage of energy transfer electric capacity is constant substantially among the present invention, so consumed energy hardly, efficient is very high, experimental results show that its efficient can reach 80%, therefore the present invention had both satisfied the harmless basic demand of energy, realize the balancing energy of battery, do not had to use complicated energy converter device again.Simple in structure, realize easily and maintenance and expansion convenient.

As Fig. 8 a, shown in the 8b, it mainly is to shift electric capacity by energy to realize that energy between two batteries of the present invention shifts, rather than inductance, so that inductance value does not need is too big, thereby reduces power consumption.The pressure reduction of the battery in the battery pack and controlled MOSFET have determined the shift direction of the energy content of battery, and the pressure drop under the normal condition on the capacitor C 1 is V _B1+ V _B2If, V _B1＞V _B2, so with Q ₁Conducting, C at this moment ₁Energy is passed through Q ₁And L ₁Transfer to B ₂In, and inductance L ₁Also store a part of battery B ₁Energy; And work as Q ₁During shutoff, D ₂Be forced to conducting, capacitor C ₁Pass through D ₂By B ₁Charging, L simultaneously ₁Energy stored is passed through D ₂B is looked in transfer ₂In, so just realized a switch periods of MOSFET from B ₁To B ₂Energy shift, current direction is as shown in Figure 8.L ₁And C ₁On waveform as shown in Figure 9.

Work as Q ₁(t during conducting ₀≤ t＜t ₁), have as shown in the formula establishment:

${\mathrm{<figure-callout\; id="1"\; label="V\; B"\; filenames="HSA00000203340700011.png,HSA00000203340700012.png"\; state="\{\{state\}\}">V</figure-callout>}}_B={\mathrm{<figure-callout\; id="1"\; label="L"\; filenames="HSA00000203340700011.png,HSA00000203340700012.png"\; state="\{\{state\}\}">L</figure-callout>}}_1\frac{{\mathrm{<figure-callout\; id="1"\; label="di\; L"\; filenames="HSA00000203340700011.png,HSA00000203340700012.png"\; state="\{\{state\}\}">di</figure-callout>}}_L}{\mathrm{dt}},$ i _L1(t ₀)＝0 1

${\mathrm{<figure-callout\; id="2"\; label="V\; B"\; filenames="HSA00000203340700011.png,HSA00000203340700012.png"\; state="\{\{state\}\}">V</figure-callout>}}_B=-{\mathrm{<figure-callout\; id="1"\; label="L"\; filenames="HSA00000203340700011.png,HSA00000203340700012.png"\; state="\{\{state\}\}">L</figure-callout>}}_1\frac{{\mathrm{<figure-callout\; id="1"\; label="di\; L"\; filenames="HSA00000203340700011.png,HSA00000203340700012.png"\; state="\{\{state\}\}">di</figure-callout>}}_L}{\mathrm{dt}}+\frac{1}{{\mathrm{<figure-callout\; id="1"\; label="C"\; filenames="HSA00000203340700011.png,HSA00000203340700012.png"\; state="\{\{state\}\}">C</figure-callout>}}_1}\&Integral;i_{C11}\mathrm{dt}---2$

V _C1(t ₀)＝V _B1+V _B2 3

Flow through battery B this moment ₁Electric current be i _B1So, have by Kirchhoff's law:

i _L1＝i _B1+i _C11 4

Work as Q ₁Turn-off D ₂(t when being forced to conducting ₁≤ t＜t ₂), have as shown in the formula establishment:

${\mathrm{<figure-callout\; id="1"\; label="V\; B"\; filenames="HSA00000203340700011.png,HSA00000203340700012.png"\; state="\{\{state\}\}">V</figure-callout>}}_B=-{\mathrm{<figure-callout\; id="1"\; label="L"\; filenames="HSA00000203340700011.png,HSA00000203340700012.png"\; state="\{\{state\}\}">L</figure-callout>}}_1\frac{{\mathrm{<figure-callout\; id="1"\; label="di\; L"\; filenames="HSA00000203340700011.png,HSA00000203340700012.png"\; state="\{\{state\}\}">di</figure-callout>}}_L}{\mathrm{dt}}+\frac{1}{{\mathrm{<figure-callout\; id="1"\; label="C"\; filenames="HSA00000203340700011.png,HSA00000203340700012.png"\; state="\{\{state\}\}">C</figure-callout>}}_1}{\&Integral;i}_{\mathrm{<figure-callout\; id="12"\; label="C"\; filenames="HSA00000203340700021.png,HSA00000203340700041.png"\; state="\{\{state\}\}">C</figure-callout>}12}\mathrm{dt},i_{L1}\left(t_1\right)=I_p---5$

V _C1(t ₁)＝V _B1+V _B2 (6)

${\mathrm{<figure-callout\; id="2"\; label="V\; B"\; filenames="HSA00000203340700011.png,HSA00000203340700012.png"\; state="\{\{state\}\}">V</figure-callout>}}_B=L_1\frac{\mathrm{<figure-callout\; id="1"\; label="d\; i\; L"\; filenames="HSA00000203340700011.png,HSA00000203340700012.png"\; state="\{\{state\}\}">d</figure-callout>}{i}_L{1}_{}}{\mathrm{dt}}---\left(7\right)$

Flow through battery B this moment ₂Electric current be i _B2So, have by Kirchhoff's law:

i _L1＝i _B2+i _C12 (8)

Suppose Q ₁A switch periods be T _S, D is Q ₁The ratio of ON time and switch periods, i.e. duty ratio.According to C in the switch periods ₁On the balance of mean charge, have:

i _C11DT _S-i _C12(1-D)T _S＝0 (9)

Can obtain by above formula:

$T_S={2I}_{L1}{[\frac{V_{B1}}{L_1}{\mathrm{<figure-callout\; id="2"\; label="D"\; filenames="HSA00000203340700011.png,HSA00000203340700012.png"\; state="\{\{state\}\}">D</figure-callout>}}^2+\frac{V_{B2}}{L_1}{(1-D)}^2]}^{-1}---\left(10\right)$

Thereby the PWM frequency that can obtain switch (MOSFET) is:

$f=\frac{1}{T_S}---\left(11\right)$

Work as V _B2＞V _B1The time, same earlier with Q ₂Q is turn-offed in conducting again after a period of time ₂, this moment D ₁Be forced to conducting, thereby realized that energy is from B ₂To B ₁Transfer.

If will realize equilibrium, must control the break-make of MOSFET well, as shown in Figure 7, several MOSFET are not common ground, so need the drive circuit of application specific, the selection for driver in the drive circuit it should be noted that: the driver upper limit switching frequency that (1) is adopted must be higher than the pwm signal frequency of processor output; (2) driver is wanted to guarantee to greatest extent that output waveform is undistorted when high-frequency work.

As shown in Figure 3, described signal acquisition circuit 2 is provided with own decoder group, the first input end A of each decoder and the second input B are connected on the described main control unit 3 gating control ends through bus in this decoder group, the output group of decoder is connected on the input of relay group, the collection terminal group of relay group is connected with described battery pack, the output group of relay group connects 1 difference amplifies and the absolute value treatment circuit, and described difference is amplified and the output of absolute value treatment circuit is connected on the data input pin of described main control unit 3.

Before the strategy of decision equilibrium, need to detect in real time every batteries both end voltage.In order effectively to isolate each cell voltage analog input channel, adopt the AQW214 Photo-MOS of Panasonic relay as multiplexer, select 4 decoder 74LS139 to control the conducting of AQW214 relay with 2.The cell voltage routing inspection circuit is equipped with this relay for each cell, when needs detect the voltage of a certain batteries, only need open corresponding relay.Each cell both end voltage that collects sent into difference is amplified modulate circuit and absolute value circuit is sampled, obtain the cell terminal voltage, send into the built-in AD converter conversion of main control unit 3 then.Per 3 AQW214 relays and 1 74LS139 decoder can detect 5 batteries.

1 74LS139 has two decoders, and the first input end A of two decoders and the second input B are connected the output winding of 3, two decoders of main control unit on 3 AQW214 relays through bus.

The first output X1 of first decoder connects the first input end of first relay;

The second output X2 of first decoder connects the first input end of second relay;

The 3rd output X3 of first decoder connects the first input end of the 3rd relay;

The first output Y1 of second decoder connects second input of first relay;

The second output Y2 of second decoder connects second input of second relay;

The 3rd output Y3 of second decoder connects second input of the 3rd relay;

The positive pole of one termination, the first battery B1 of first relay, first switch, the first input end of another termination difference channel of first relay, first switch;

One end of the first relay second switch connects the negative pole of the first battery B1 and the positive pole of the second battery B2, second input of another termination difference channel of the first relay second switch simultaneously; The output termination of difference channel is amplified the input of follow circuit, amplifies the input of the output termination absolute value circuit of follow circuit, the output termination main control unit 3 of absolute value circuit.

One end of second relay, first switch connects the negative pole of the second battery B2 and the positive pole of the 3rd battery B3 simultaneously, the first input end of another termination difference channel of second relay, first switch;

One end of the second relay second switch connects the negative pole of the 3rd battery B3 and the positive pole of the 4th battery B4, second input of another termination difference channel of the second relay second switch simultaneously; The output termination of difference channel is amplified the input of follow circuit, amplifies the input of the output termination absolute value circuit of follow circuit, the output termination main control unit 3 of absolute value circuit.

One end of the 3rd relay first switch connects the negative pole of the 4th battery B4 and the positive pole of the 5th battery B5 simultaneously, the first input end of another termination difference channel of the 3rd relay first switch;

One end of the 3rd relay second switch connects the negative pole of the 5th battery B5 and the positive pole of the 6th battery B6, second input of another termination difference channel of the 3rd relay second switch simultaneously; The output termination of difference channel is amplified the input of follow circuit, amplifies the input of the output termination absolute value circuit of follow circuit, the output termination main control unit 3 of absolute value circuit.

The AQW214 corresponding pin be linked in sequence cell termination B1, B2, B3, B4 ..., B6 wherein the negative pole of the 5th battery be exactly B6, if N piece battery then is Bn+1, it is that low level is effective that system makes corresponding Xn and Yn by control as the several XUANT pin of U2 among Fig. 3, and the cell voltage that gating collects is sent into the ADC module samples.As being gated low level as pin X1, Y1, then the first segment battery is admitted to sampling channel; When pin X2, Y1 are gated low level, then second batteries is admitted to sampling channel; When pin X2, Y2 are gated low level, then the 3rd batteries is admitted to sampling channel, by that analogy.

The every order of Single Chip Microcomputer (SCM) program changes a 74LS139 output level, but the just voltage of sequential sampling respective battery.Because adjacent double sampling polarity is opposite, so need absolute value circuit in the sample circuit.In the latter half of Fig. 3, because the series connection of several batteries, the voltage that obtain cell just must subtract each other both behind the absolute voltage of gathering the battery two ends, obtains difference.Difference channel U5C is exactly that the electromotive force of the battery-end that will collect subtracts each other the voltage that obtains cell, is the difference amplifier section, only only puts to be twice.Amplifying follow circuit U5D partly is voltage follower circuit, and the part of back is an absolute value circuit, with the generating positive and negative voltage that collects all be converted on the occasion of, enter AD converter then.

And the like, a unlimited decoder and relay be can be connected in series, and difference amplification modulate circuit and absolute value circuit connected respectively, difference is amplified modulate circuit and absolute value circuit gets the input interface that output is connected on main control unit 3.

Be serially connected with Hall current sensor between described battery pack and diverter switch K, the output of this Hall element connects the piezoelectric voltage of described main control unit 3 and gathers input.

Each battery is other in described battery pack is fixed with temperature sensor, and the output of described temperature sensor is connected on the temperature input port of described main control unit 3 through bus.

The electric current of the state of monitoring charging in real time monitoring charging in real time.The electric current that the state that monitoring in real time discharges and recharges also needs monitoring in real time to discharge and recharge.In current measurement techniques, in order to reduce the influence of measuring circuit, adopt the sample resistance of a little resistance of series connection in circuit-under-test to carry out the IV conversion usually to tested electric current, realize the method that small voltage amplifies through differential amplifier circuit again.Certainty of measurement requires high more, and circuit is just complicated more.

And be that the Hall current sensor LTS25-N that uses lime company detects electric current in the native system, it is+the 5V power supply that measuring range is 0-± 80A, at I _PNDuring=0A, be output as 2.5V; When measuring reverse current, be 0.5V-2.5V; When measuring positive current, be 2.5V-4.5V, just within the input range of AD.It is 0.7% that band carries certainty of measurement, than higher; Temperature range-40-+85 is broad also.Then this voltage is delivered to the AD converter input of main control unit 3, thereby realized the accurate sampling of charging and discharging currents.

In addition, the temperature of detection battery that can also be real-time prevents that the battery excess temperature from blasting, employing be the DS18B20 digital temperature sensor of the monobus produced of DALLAS (Dallas) company of high accuracy, high reliability.Here with a plurality of DS18B20 with the mode of bus connect together with its link to each other with an IO mouth conversion of finishing the many places temperature with read.

As shown in figure 10, the drive controlling end group of described main control unit 3 is connected with 2N-2 Drive and Control Circuit, each Drive and Control Circuit is provided with the prime reverser, the input of this prime reverser connects described main control unit 3, output is after first light-coupled isolation, be connected the input of back level reverser, the output of back level reverser is connected the input of MOSFET drive controlling chip, and the output of MOSFET drive controlling chip connects the first semiconductor switching device Q1 or the second semiconductor switching device Q2 in the described drive circuit 4.

That the present invention adopts is the special-purpose MOSFET drive controlling chip I R2103 that American I R company produces, it is a kind of binary channels high pressure, high speed voltage-type device for power switching gate drivers, have independently high-end and the low side output channel, the power supply of floating adopts boostrap circuit, its high-end operating voltage can reach 600V, the gate drive voltage scope of output is 10～20V, logic supply voltage scope 5～15V.Satisfy the demand of design fully.IO mouth by main control unit 3 produces square wave earlier, through digital light-coupled isolation, receives IR2103 and MOSFET.Application circuit as shown in figure 11,12V is fixing power supply, C26 is a bootstrap capacitor, power supply charges to C26 through D11, load, MOSFET, the grid of MOSFETI pipe drives by enough energy storage on the C26.Consider that it is the reliable key that drives that bootstrap capacitor C26 stablizes quick charge, and the desired switching frequency of native system is about 10KHz, so the Capacity Selection of C26 is less than 10uF.

As shown in figure 10, the output VQ1 of MOSFET drive controlling chip connects the control end of the described first semiconductor switching device Q1.Input VQG1 connects the switch front end of the first semiconductor switching device Q1, thereby realizes the driving of floating ground semiconductor switching device.

As shown in Figure 1, the positive pole of the first batteries of described battery pack connects the stiff end of diverter switch K, and first movable end of this diverter switch K is acted in collusion to make each other's confessions and connect the negative pole of described battery pack minor details battery behind the power supply;

Connect the negative pole of described battery pack minor details battery after the second movable end string load of described diverter switch K.

The charging control end of described main control unit 3 also is connected with charging control circuit 5, and this charging control circuit 5 is serially connected between described power supply and the first batteries of battery pack;

As shown in Figure 4, described charging control circuit 5 is provided with second optocoupler, the positive input of this second optocoupler connects positive supply, negative input connects described main control unit 3, the negative sense output head grounding of second optocoupler, the grid of forward output termination switch transistor T, the source electrode of this switch transistor T connects described power supply, drain electrode connects the front end of stabilizing inducatnce, ground connection behind the rear end string electric capacity of voltage regulation of stabilizing inducatnce, also order is to the positive pole of diode in the rear end of this voltage stabilizing inductance, and the negative pole of this unilateral diode connects first movable end of described diverter switch K.

Charging control circuit 5 adopts pulse-width modulation (PWM) mode to control the size of supply current.The PWM ripple is controlled its increase or is reduced pulsewidth by the PWM mouth output of main control unit 3.Pwm signal is by the MOSFET on the photoelectricity isolation drive major loop.Switching tube, diode, lc circuit constitute switching power supply.The Switching Power Supply of controlling with the PWM mode can reduce power consumption, is convenient to carry out Digital Control simultaneously.

Not only relate to the balancing energy control of batteries charging among the present invention, also has the balancing energy control of discharge, so will the state that discharge and recharge be switched, present technique can realize that this switch is aforesaid diverter switch K by the single-pole double-throw switch (SPDT) of being made up of two MOSFET.One of them is used for the conducting charge circuit, and another one is used for the conducting discharge loop.Two MOSFET are used as conducting voltage by the voltage of getting charge power supply and battery pack respectively, link to each other with the IO mouth of single-chip microcomputer by optocoupler, realize break-make control.

In addition, also have function button, power supply, LCD12864 display circuit and the oscillating circuit relevant and reset circuit etc., when PCB layout, numerical portion is partly separated with simulating, to reduce the phase mutual interference with single-chip microcomputer.

Claims (7)

1. a charge-discharge battery pack equilibrium management system comprises N battery and N-1 non-dissipative equalizing charge-discharge circuit (1), N battery strings composition battery pack that is connected together, and every adjacent two batteries are connected with same non-dissipative equalizing charge-discharge circuit (1) in the battery pack;

Signal acquisition circuit (2): the voltage of gathering every batteries in the battery pack;

Main control unit (3): control the work schedule of described signal acquisition circuit (2), obtain the magnitude of voltage that collects, control the work schedule of 2N-2 drive circuit (4);

Drive circuit (4): the operating state of per two drive circuits (4) non-dissipative equalizing charge-discharge circuits of control (1); Described non-dissipative equalizing charge-discharge circuit (1) comprises energy storage inductor (L1), first semiconductor switching device (Q1) and second semiconductor switching device (Q2);

The positive pole of prime battery in described adjacent two batteries of termination behind the switch of first semiconductor switching device (Q1) wherein, connect the negative pole of prime battery behind the described energy storage inductor of switch front end string (L1), the switch front end of this first semiconductor switching device (Q1) also connects the positive pole of first diode (D1), and the negative pole of this first diode (D1) connects the switch rear end of first semiconductor switching device (Q1);

Wherein the switch rear end of second semiconductor switching device (Q2) is connected with the switch front end of described first semiconductor switching device (Q1), the switch front end of second semiconductor switching device (Q2) connects the negative pole of level battery in back in adjacent two batteries, the switch front end of this second semiconductor switching device (Q2) also connects the positive pole of second diode (D2), and the negative pole of this second diode (D2) connects the switch rear end of second semiconductor switching device (Q2);

The control end of described first semiconductor switching device (Q1) and second semiconductor switching device (Q2) is connected on respectively on the output (VQ1) of first drive circuit and second drive circuit;

It is characterized in that: be serially connected with storage capacitor (C1) between the switch front end of the switch rear end of described first semiconductor switching device (Q1) and second semiconductor switching device (Q2).

2. charge-discharge battery pack equilibrium management system according to claim 1, it is characterized in that: described signal acquisition circuit (2) is provided with own decoder group, the first input end (A) of each decoder and second input (B) are connected on described main control unit (3) the gating control end through bus in this decoder group, the output group of decoder is connected on the input of relay group, the collection terminal group of relay group is connected with described battery pack, the output group of relay group is connected with 1 difference amplification and absolute value treatment circuit with the form of bus, and described difference is amplified and the output of absolute value treatment circuit is connected on the data input pin of described main control unit (3).

3. charge-discharge battery pack equilibrium management system according to claim 1, it is characterized in that: the drive controlling end group of described main control unit (3) is connected with 2N-2 Drive and Control Circuit, each Drive and Control Circuit is provided with the prime reverser, the input of this prime reverser connects described main control unit (3), output is after first light-coupled isolation, be connected the input of back level reverser, the output of back level reverser is connected the input of MOSFET drive controlling chip, and the output of MOSFET drive controlling chip connects first semiconductor switching device (Q1) or second semiconductor switching device (Q2) in the described drive circuit (4).

4. charge-discharge battery pack equilibrium management system according to claim 1, it is characterized in that: the positive pole of the first batteries of described battery pack connects the stiff end of diverter switch (K), and first movable end of this diverter switch (K) is acted in collusion to make each other's confessions and connect the negative pole of described battery pack minor details battery behind the power supply.

Connect the negative pole of described battery pack minor details battery after the second movable end string load of described diverter switch (K).

5. charge-discharge battery pack equilibrium management system according to claim 4, it is characterized in that: the charging control end of described main control unit (3) also is connected with charging control circuit (5), and this charging control circuit (5) is serially connected between described power supply and the first batteries of battery pack;

Described charging control circuit (5) is provided with second optocoupler, the positive input of this second optocoupler connects positive supply, negative input connects described main control unit (3), the negative sense output head grounding of second optocoupler, the grid of forward output termination switching tube (T), the source electrode of this switching tube (T) connects described power supply, drain electrode connects the front end of stabilizing inducatnce, ground connection behind the rear end string electric capacity of voltage regulation of stabilizing inducatnce, also order is to the positive pole of diode in the rear end of this voltage stabilizing inductance, and the negative pole of this unilateral diode connects first movable end of described diverter switch (K).

6. charge-discharge battery pack equilibrium management system according to claim 4, it is characterized in that: be serially connected with Hall current sensor between described battery pack and diverter switch (K), the output of this Hall element connects the voltage acquisition input of described main control unit (3).

7. charge-discharge battery pack equilibrium management system according to claim 1, it is characterized in that: each battery is other in described battery pack is fixed with temperature sensor, and the output of described temperature sensor is connected on the temperature input port of described main control unit (3) through bus.

Images