electric drive system for electric cars, the main and most core, the most complex parts. general drive system has the following requirements：
the instantaneous power, short-time overload capacity is strong, so as to meet the needs of climbing and accelerate;
wide range of speed regulation;
in running full speed range and load range, high efficiency, all the work within the scope of integrated in the motor with high efficiency, to try to improve the electric car trip range a;
high reliability, easy to use simple, low cost;
high power density, small volume, light quality.
fast torque response and rapid reaction in the scope of all kinds of speed and control the driving and braking torque, softly in motor systems, motor control demanding, good steady precision and dynamic characteristic;
security, stability, prevent certain impact, long service life.