A power system of an electric vehicle, comprising: a high voltage battery, a low voltage storage battery, a main drive motor and an electronic controller for the main drive motor, and an auxiliary drive motor and an electronic controller for the auxiliary drive motor, wherein the main drive motor and the electronic controller for the main drive motor are powered by the high voltage battery; wherein the auxiliary drive motor comprises a high voltage winding and a low voltage winding; wherein the electronic controller of the auxiliary drive motor comprises a high voltage electronic controller and a low voltage electronic controller, wherein the high voltage battery and the high voltage winding of the auxiliary drive motor are connected via the high voltage electronic controller of the auxiliary drive motor, and the low voltage storage battery and the low voltage winding of the auxiliary drive motor are connected via the low voltage electronic controller of the auxiliary drive motor; wherein the high voltage electronic controller of the auxiliary drive motor is configured to operate constantly by rotating at a constant speed under the rotation speed closed loop mode in response to determining that the high voltage battery is normal; and wherein the low voltage electronic controller of the auxiliary drive motor is configured to: operate constantly by rotating at a constant speed in a rotation speed closed loop mode in response to determining that the high voltage battery fails, and operate in a torque control mode to charge the low voltage storage battery in response to determining that the high voltage battery is normal and a state of charge of the low voltage storage battery is lower than a first preset value, wherein the low voltage electronic controller of the auxiliary drive motor is further configured to stop the torque control mode in response to determining that the high voltage battery is normal and the state of charge of the low voltage is higher than a second preset value, wherein the second preset value is greater than the first preset value. a high voltage battery, a low voltage storage battery, a main drive motor and an electronic controller for the main drive motor, and an auxiliary drive motor and an electronic controller for the auxiliary drive motor, wherein the main drive motor and the electronic controller for the main drive motor are powered by the high voltage battery; wherein the auxiliary drive motor comprises a high voltage winding and a low voltage winding; wherein the electronic controller of the auxiliary drive motor comprises a high voltage electronic controller and a low voltage electronic controller, wherein the high voltage battery and the high voltage winding of the auxiliary drive motor are connected via the high voltage electronic controller of the auxiliary drive motor, and the low voltage storage battery and the low voltage winding of the auxiliary drive motor are connected via the low voltage electronic controller of the auxiliary drive motor; wherein the high voltage electronic controller of the auxiliary drive motor is configured to operate constantly by rotating at a constant speed under the rotation speed closed loop mode in response to determining that the high voltage battery is normal; and wherein the low voltage electronic controller of the auxiliary drive motor is configured to: operate constantly by rotating at a constant speed in a rotation speed closed loop mode in response to determining that the high voltage battery fails, and operate in a torque control mode to charge the low voltage storage battery in response to determining that the high voltage battery is normal and a state of charge of the low voltage storage battery is lower than a first preset value, wherein the low voltage electronic controller of the auxiliary drive motor is further configured to stop the torque control mode in response to determining that the high voltage battery is normal and the state of charge of the low voltage is higher than a second preset value, wherein the second preset value is greater than the first preset value. operate constantly by rotating at a constant speed in a rotation speed closed loop mode in response to determining that the high voltage battery fails, and operate in a torque control mode to charge the low voltage storage battery in response to determining that the high voltage battery is normal and a state of charge of the low voltage storage battery is lower than a first preset value, wherein the low voltage electronic controller of the auxiliary drive motor is further configured to stop the torque control mode in response to determining that the high voltage battery is normal and the state of charge of the low voltage is higher than a second preset value, wherein the second preset value is greater than the first preset value.