Research On The Monitoring And Control System Of The Voltage Disturbance Generator

Power quality has aroused more and more attention of users. How to solve power quality problems in power system is a research focus recently. Development of the Composite Voltage Disturbance Generator, to simulate the voltage sag and swell, over voltage and under voltage, voltage fluctuation and flicker, voltage unbalance, harmonic and complex disturbances, is of great significance for research into monitoring and improving power quality accurately and quickly. It will help develop the voltage compensation device and carry out various experimental verifications. Moreover the device can be a test equipment for the sensitive load with tolerance to disturbance. Based on the project "Composite Power Quality Control Techniques and Devices", this paper has carried out deep research regarding the monitoring and control system which is the core of the device.The function of the monitoring and control system is to monitor the device operational status and produce controlled voltage disturbances. Advanced power electronics technology is applied. The cascaded H-bridge rectifier and inverter units for the main circuit are composed of IGBT devices. The voltage disturbance generator connects with the grid in series to take in power and output disturbance voltage. The digital host controller based on DSP and FPGA is responsible for human-computer interface and IO, and realize the control algorithm to generate the driving pulse signals for IGBTs. The industrial control computer communicates with the bottom control system through RS422 bus. The monitoring software with multiple control and protection functions, developed using LabVIEW, issues commands and parameters, and displays various types of feedback information.This paper has described the reasons, harms, control and testing technologies of power quality problems. The device's working principles and control strategies were analyzed and simulated in PSCAD. The development processes of DSP+FPGA control system and human-computer interactive system were explained in detail. The reliability of control system and the feasibility of the device were verified through hardware experiments.