In view of the slow detection and response speed of TSC Dynamic Reactive Power Compensation to dynamic load and the failure to realize complete reactive power compensation, a simulation model of dynamic reactive power compensation system based on Newton iterative control is constructed. On the basis of function relation fitting between control variables and reactive power compensation power, the model is solved by Newton iteration and optimal control, and fast dynamic reactive power compensation is realized by judging the compensation reactive power interval. The simulation results show that the system can realize real-time, fast and continuous reactive power compensation of fixed load and dynamic reactive load, with small steady-state error and fast response speed.