Reactive Power Compensation And Harmonic Suppression Of Distribution Network

Reactive power compensation and harmonic suppression of distribution network is a quite new research and practical domain, and along with unceasing enhancement of customer demand for electrical energy quality, it has caused more attention. Because STATCOM has more merits than SVC, such as responding much faster,the effect of raising voltage momentary stability better and with less harmony, it has been applied from transmission network to distribution network(namely DSTATCOM) now. At present, DSTATCOM has represented development direction of reactive power compensation and harmonic suppression of distribution network.This thesis revolves design and application of the direct electric current control DSTATCOM.The main contents are as follows:1. Design of DSTATCOMFirstly, In order to enhance precision and reliability of high power convert,A novel circuit structure of hybrid-type-component is established, and time-sharing method is added to parallel-connected devices.Secondly, In order to enhance the precision of real-time measure of reactive current, id-iq method is used in the place of ip-iq method.Based on these designs, a series of simulations are performed, and the simulation results have proved all above feasible and effective .2. Application of DSTATCOMParameter selection method for STATCOM parallel-connected by capacitor(or capacitor series-connected with reactor) is proposed with corresponding example.