System and method for load test of diesel generating set

The invention discloses a system for the load test of a diesel generating set, which is used for supplying power for the load in load test of the diesel generating set so as to reduce the energy consumption. The system comprises an input isolating potential device, a PWM (Pulse Width Modulation) rectifying device, a direct current chopped wave device, a PWM inverter, a filtering device and an output isolating potential device which are connected in sequence; the input isolating potential device is used for isolating the diesel generating set from the PWM rectifying device; the PWM rectifying device is used for converting the alternating current voltage output by the diesel generating set into direct current voltage; the direct current chopped wave device is used for carrying out direct current protection on the direct current voltage; the PWM inverter is used for converting the direct current voltage into three-phase alternating current voltage; the filtering device is used for reducing the harmonic content in the three-phase alternating current voltage; and the output isolating potential device is used for isolating the PWM inverter from a load and supplying the three-phase alternating current voltage to the load for use. The invention further discloses a method for the load test of the diesel generating set.