1. Study on DC side harmonic performance of VSC HVDC
- Author
-
Mao Hangyin, Chen Jingsi, Yang Jie, Sun Tongyue, Du Zhenyu, and Yang Yuexi
- Subjects
Physics ,Harmonic analysis ,Electric power transmission ,Steady state (electronics) ,Transmission line ,Harmonic ,Thévenin's theorem ,Topology ,Electrical impedance ,Signal injection - Abstract
This paper presents practical methods for dc side steady state harmonic calculation to analyze harmonic performance along the dc transmission line for the VSC based HVDC system. First, a general dc side harmonic calculation method based on Thevenin's equivalent and IEC general summation law is introduced. The converter and corresponding dc transmission line on both sides are represented as a harmonic voltage source U h and the harmonic impedance Z h seen from each dc side. Different from traditional AC side harmonic calculation which uses the envelopes of harmonic impedance loci, the methods in this paper compute all possible combinations of harmonic impedances covering all operation scenarios, which could easily find out the worst scenario. Second, an improved calculating method for the considering the harmonic model with multi-section dc transmission line harmonic impedance is proposed to improve the computational efficiency. And then, an accommodated harmonic impedance measurement for the dc side application based on small signal injection method is described. Finally, the PSCAD/EMTDC simulation verifications have been carried out based on a ±500kV/2000MW VSC HVDC system to verify the effectiveness of the proposed method.
- Published
- 2020