Power supply control method and system for low-voltage load of electric automobile and automobile

The invention discloses a power supply control method and system for a low-voltage load of an electric automobile and the automobile. The power supply control method comprises the steps that a high-efficiency interval of a DCDC converter and a high SOC interval of a 12V small battery are set; real-time required power of the low-voltage load is monitored in real time, whether the real-time required power of the low-voltage load is within the high-efficiency interval of the DCDC converter or not is judged, and if yes, the DCDC converter is adopted to directly provide low-voltage power supply for the low-voltage load. The method has the advantages that the control logic of low-voltage power supply is designed from the conversion efficiency of the DCDC converter for supplying power to the low-voltage load, so that the conversion efficiency is improved, and energy waste under low efficiency is reduced. 本发明公开了一种电动汽车低压负载的供电控制方法、系统及汽车，包括设置DCDC转换器的高效率区间和12V小电池的高SOC区间；实时监测低压负载的实时需求功率，判断低压负载的实时需求功率是否在DCDC转换器的高效率区间内，若是，则