Time Domain Particle Swarm Optimization of PI Controllers for Bidirectional VSC HVDC Light System

This paper proposes a novel technique to tune the PI controllers of a bidirectional HVDC light system by embedding particle swarm optimization directly in the Simulink model in the design procedure. The HVDC light system comprises of a rectifier station, a DC link, and an inverter station. Each converter station requires four PI controllers to be tuned in the decoupled d-q vector control scheme, and with the bidirectional HVDC system, the required PI controllers are doubled. Tuning these many controllers using conventional methods is a challenging task, especially if the parameters of the converter stations are different. A novel approach to tune the PI controllers for a bidirectional HVDC system using the time-domain performance indices is presented in this paper. The time-domain performance indices are optimized using the particle swarm optimization (PSO) algorithm. The results of the proposed tuning method show that the proposed method not only gives superior results but also is less cumbersome to tune compared to conventional methods like modulus optimum (MO).

HVDC Light Transmission System with Fuzzy Logic Based PI Controller

In the recent times there are many advancements in the sector of power electronic equipment. HVDC transmission system is further developed into HVDC light transmission system by replacing of thyristor valves with IGBT valves. There are a lot of advantages with HVDC light system compared to normal HVDC. When HVDC light transmission is confronted with fault, then the voltage and current vary, and they takes more time to come back to their steady state with PI controller. In this paper fuzzy logic based PI controller is proposed to reduce the time to reach their normal state, and improve the system steady state. The recommended controller is compared with traditional PI (proportional integral) controller for different control requirements, DC voltage, and reactive power under sudden disturbances such as three phase to ground fault. The performance of HVDC light system with traditional PI and fuzzy-PI shall be tested on under three-phase faults using MATLAB-Simulink software

Fault Diagnosis Simulation of Light High Voltage Direct Current Transmission System

High Voltage Direct Current (HVDC) system was often the link between major power grids. In order to ensure the safe operation of HVDC, fault diagnosis method was studied. The system structure of HVDC Light system was analyzed, and the normal and fault conditions of the transmission system were simulated in the Matlab platform. This method was very convenient and simple, and it could restore the real situation. The use of simulated waveform could effectively identify the fault types of actual situation, and then it was a flexible, efficient and practical method of fault diagnosis in HVDC Light system.

Research on an AC/DC Converter Based on the Convert Station in HVDC Light Technology

In this research, a converter, suitable for the convert station of the HVDC light technology, is proposed and optimized. The converter mainly consists of AC chopper, rectifier transformer, low-pass filters and smoothing reactor. This system can restrain the disturbance of the input power and output the power with high quality. This research is going to analyze the working principle of the converter and then optimize the output wave through filters. Circuit’s simulation is carried out by MATLAB to verify the reliability and feasibility of this converter topology.

Study on Light HVDC Converter and Harmonic Suppression of the Active Filter

The key equipment of Light HVDC Technology is the converter and the filter. The main function of the converter is AC / DC conversion, which plays a vital role in converter station. The filter is also an important tool for harmonic suppression. Therefore, in this paper, the HVDC converter and the harmonic suppression are studied. Our paper discussed the advanced converter VSC which is currently being put into operation, its key technology--the MMC topology and the connection mode of VSC. Meanwhile, the production, effect and suppression of the harmonic are analyzed. Compared active power filter to the passive filter, finally, we chose the active filter as the research object. Successful experience of the HVDC Light project which has been put into operation or will be put into use showed that, the technology is in great progress and will be widely used.