How does this electric car achieve such high performance? Inside the inverter lies both the brains and the power control of the EV1 propulsion system. The Power Control Module (PCM) is the command center and the six hybrid power modules distribute the power. Each of these hybrid power modules contains six Insulated Gate Bipolar Transistors (IGBTs) for a total of 36 power transistors. The IGBTs are responsible for controlling the flow of electric energy and the high power switching needed to convert the Direct Current (DC) of the battery to the pulsed Alternating Current (AC) for the motor to use as much as 102 kilowatts, enough to power two 50,000-watt, clear channel AM radio stations. Working together, these IGBTs are rated to handle up to 600 volts and 600 amps for the Gen II EV1.
In regenerative braking mode, the inverter also takes energy back from the motor and routes it into the battery, extending the range potential of the EV1. The inverter itself weighs just 27 kilograms (60 pounds) and is very reliable. Its liquid-cooled and so efficient that it doesn't generate much heat only 600 watts in normal driving conditions. Incidentally, you can recover the heat from the inverter and supplement the heat from the heat pump to save energy. This is done automatically in the EV1 whenever you set the controls for heat.
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