Power system of electric vehicle, electric vehicle comprising the same and method for heating battery group of electric vehicle

A power system of an electric vehicle, comprising:

• a battery group;
• a battery heater, connected with the battery group and configured to charge and discharge the battery group to heat the battery group;
• a battery management device, connected with the battery group and the battery heater respectively, and configured to control the battery heater to heat the battery group intermittently when a temperature of the battery group is lower than a first temperature threshold and a residual electric quantity of the battery group is larger than an electric quantity threshold;
• an electric distribution box, configured to distribute a voltage output by the battery group;
• a motor;
• a motor controller, connected with the motor and the electric distribution box respectively, comprising a first input terminal, a second input terminal and a pre-charging capacitor connected between the first input terminal and the second input terminal, and configured to supply power to the motor according to a control command and a voltage distributed by the electric distribution box;
• and
• an isolation inductor, connected between the battery group and the electric distribution box, wherein an inductance of the isolation inductor matches with a capacitance of the pre-charging capacitor.