A control system provided in a hybrid vehicle with a combustion engine for outputting a driving force, an electric motor for generating a force for assisting the output from the engine, depending on driving conditions, a power storage unit for storing electric energy generated by the motor acting as...http://www.google.co.uk/patents/US6700213?utm_source=gb-gplus-sharePatent US6700213 - Control system for a hybrid vehicle in which output from the engine is assisted by the motor based on air-fuel ratio determination
