Abstract: The present disclosure provides a real-time simulation system for testing a controller, which outputs a control signal for controlling operations of a power converter and an AC motor. The real-time simulation system comprises a real-time simulation module, a load simulation module and an operation management and monitoring module. The real-time simulation module constructs a first model simulating the dynamic behaviors of the AC motor coupled to the mechanical load. The real-time simulation module operates a simulation program for generating a first simulation result. The load simulation module constructs a second model simulating dynamic behaviors of the mechanical load and generates a second simulation result by a simulation program. The real-time simulation module can adjust the simulation program to the first model according to the second simulation result. The operation management and monitoring module monitors the operation of the real-time simulation module and the load simulation module.