In this paper the process of transient analysis of synchronous generator is analyzed when the load is switched. After the load changed, the excitation response curve of mobile station is obtained via matlab simulation, which provides a theoretical basis for excitation control of the mobile station, then can be helpful for optimizing the motor running and the design of motor protection.

The AC electronic load circuit is studied, PWM converter is used in this circuit in order to achieve the simulation function of load characteristics.The methods of how to get the command current mathematical model and simulation module is given which is based of the Matlab/Simulink platform, Hysteresis control mode is used in order to get fast and stable actual current and then carried on the simulation of the proposed electronic load. The simulation results show that the proposed algorithm and the control instruction current method and the effectiveness of the current control method, realized the simulation of ac electronic load.