Power Quality Control Technology Research And Engineering Application

With the development of economic and technology, increasing non-linear, impact and unbalanced loads such as electric locomotive, variable-frequency speed governor and energy saving lamp were connected into power system, which leading to power quality problems such as voltage fluctuation, voltage drop and wave form distortion. These problems will seriously affect the safety operation of utility grid, even cause a big power outages;cause user’s equipment damage, product scrap, data loss and other serious loss. Therefore how to effectively comprehensively manage power system harmonic and reactive power,improve quality of power supply has become an urgent and important task.The key equipments of power quality control include active power filter(APF), static synchronous compensator(STATCOM), passive power filter and dynamic harmonic elimination reactive power compensation device. Their main functions are to dynamically and real-timely track and compensate harmonic and reactive power of power grid, eliminate waveform distortion, compensate reactive power, suppress the adverse effects of a variety of loads on power grid, improve power quality and "purify" power grid.This paper firstly analyzed the causes and damages of power quality problems, introduced several ways of power quality control technology at present, and briefly discussed the advantages and disadvantages of various kinds of power quality control technology.This paper detailed described study and design of dynamic harmonic elimination reactive power compensation device and hybrid active power filter of power quality control products. In the design of dynamic harmonic elimination reactive power compensation device, the capacitor reactor group no inrush current high speed switch technology was proposed, it realized no inrush current high speed track reactive power compensation in the environment of high harmonic, reduced the impact of capacitor switching process on power grid to lowest level, significantly reduced the inrush current impact on thyristor and capacitor, improved reliability and life of equipment. In the study and design of hybrid active power filter, compensation capacity active regulation technology was adopted which effectively solved the problems of filter halt and even burn up due to over load.At last, this paper takes rubber, chemical and ICP packing three industries as examples to detailed describe practical application of power quality control products. Proposed the viewpoints that against different problems and application situations, different products and solutions will be recommended, try to reduce the cost of investment under the premise of meeting customer requirement or meeting national standards.