Modeling And Simulation Of Unified Power Flow Controller Based On Joint Control

With the development of power industry, the increase of the transmission network construction scale, transmission technology has been paid more and more attention. Stability of the power system of electric energy transmission process, capacity and quality of power supply, can affect the future development of power grid. The unified power flow controller can independently control by using the compensator. And more important is for joint control of the compound. So it has steady and reliable control effect and very big development space.The thesis first introduces the current research on unified power flow controller research background, development process and related technology. Based on the converter working principle of unified power flow controller, the thesis builds a steady and transient model of joint control, provides the theory basis for further research on joint control principle of unified power flow controller. The thesis expounds the working principle of complete controller of joint control, puts forward different control strategies for shunt and series side under taken, designs the double closed loop feedback for two converter. By using PID decoupling calculator and controller function, the unified power flow controller model makes rapid response parameters on the transmission system, gives the accurate control signal instruction, provides the appropriate amount of compensation with reactive power and maintains the stability of line voltage.Joint control of unified power flow controller depends on two important components: static synchronous shunt compensator(STATCOM) and static synchronous series compensator(SSSC).The reference value of their mathematical models and related parameters, the thesis establishes the simulation module of two kinds of compensator. The unified power flow controller has the function of switching control mode, can realize the control function. Based on the MATLAB platform and SIMULINK, the thesis establishes simulation model of the unified power flow controller, verifies the control effect of the power flow parameters. The simulation model of unified power flow controller includes four parts detection, controller, output, system access, consists the phase-locked loop, measurement, current regulator, voltage regulator, a pulse generator module. The thesis makes graphical user interface to set the important parameters of power, voltage standard value and variation, and sets oscilloscope to observe waveform changes of system parameters at each node simulation model. Through the observation of the simulation result, the thesis verifies that, based on the joint control, the unified power flow controller has a stable, accurate control effect for wattles power compensation and voltage constant system.