Inertia compensasion control of engine test bench

An engine test bench is utiliezed to execute a performance test, durability test and etc. of a vehicle engine. In these tests, there is a process that the engine must become an idling state. Figure 1 shows a typical mechanical configuration of the engine test bench. To make the engine an idling state, a dynamometer must be controlled so that the engine becomes no-load state. Only by controlling a measured value of a torque meter (shaft torque) to 0Nm, the engine carries shaft inertia. So, to make the engine no-load state, it is necessary to compensate the inertia of the coupling shaft by dynamometer control.