Research Of Dynamic Reactive Power Compensation Device Based On DSP In The Distribution Network

With the popularity of low voltage distribution network, nonlinear impact loads graduallyjoin, the power supply quality has seriously affected; Therefore, the use of dynamic reactivepower compensation method plays an important role in improving the quality of power gridvoltage and ensuring the normal and stable operation system; With the semiconductortechnology and control technology development, it makes the traditional reactive powercompensation device gradually quit the stage of history, which will be replaced by static vargenerator who has high compensated speed, high precision compensation, wide compensationrange,and aslo it gradually becomes one of a kind of important equipment in flexible ac-transmission system.This paper aims at dynamic reactive power compensation device in the distribution network,which is based on DSP; First of all, it refers to a vast amount of present research situation forreactive power compensation device on abroad and home; and then derives compeletly the powerfactor calculation methods in the linear and nonlinear circuit, which lays the foundation foranalysising the static var generator (SVG) work principle and instantaneous reactive powertheory; In the basis of above instantaneous reactive power theory, this paper focuses more onreactive power current detection method and control method, in order to achieve the real-timeaccurate compensation for grid; But, in the three-phase network, the system is always in theasymmetric state, there are some deviations in detecting the current and phase signal, therefore,this paper puts forward with the positive sequence quantity extraction matrix extraction positivesequence component method, which can extract effectively positive sequence component from Aphase voltage; Current control has two kinds of methods,that’s indirect and direct control,on thebasis of fully contrast, this paper chooses direct current control method based on dqtransformation; In view of above introduction,this section mainly designs the hardware circuit ofreactive power compensation device, chooses the suitable control chip TMS320LF2407A for thiscompensation system, calculates the relevant power parameters and selects the main device model and heat shielding measures to meet with compensation requirements and controlaccuracy; For realizing the need of sine wave, this paper adopts the space voltage vectorSVPWM control mode; finally,this paper designs the system software and built the mainfunction modules of the simulation model, using the MATLAB simulation to verify thecompensation system of compensation effect, it turns out that the effect is good.