Power supply conversion device for electric automobile and electric automobile

The invention discloses a power supply conversion device for an electric automobile and the electric automobile. The power supply conversion device comprises a direct-current power supply and a controller, wherein the direct-current power supply is provided with a high-voltage input interface and a low-voltage output interface, and comprises a plurality of direct-current converters which are mutually connected in parallel, the high-voltage input interface is connected with a power battery of the electric automobile, and the low-voltage output interface is connected with the low-voltage load of the electric automobile; the controller is connected with the direct-current converters to be used for controlling the starting and the closing of the direct-current converters according to the requirement of the low-voltage load for electricity energy. The power supply conversion device disclosed by the invention has the following advantages that the direct-current converters with high switching frequency and high power density are connected in parallel to realize the transformation of power supplies, the power supply conversion device has high frequency, light weight and high energy efficiency, the whole volume of the power supply conversion device is substantially reduced, reducing the vehicle body space of the complete vehicle is facilitated, and the integration of the complete vehicle is convenient; through the control mode that a power module is started as needed, the working efficiency of the entire load range of the power supply conversion device is effectively improved, the electric energy is saved, and the endurance mileage of the complete vehicle is extended.