The diesel engine electric dynamometer test bench system uses an AC electric dynamometer as its test core and is equipped with an imported four-quadrant active variable frequency inverter system as its controller. It can operate in four quadrants and directly feed energy back into the grid. The XLE-1000 measurement and control system serves as the control core, automatically completing test cycles defined by regulations and purchasers. It can integrate external auxiliary equipment such as transient fuel consumption meters and thermostats, and is equipped with a data acquisition system to collect engine parameters, which are then recorded, processed, displayed, and generated into test reports in real time.