What’s the main reason for abnormal damage of reactive power compensation components?

● Abstract

Using reactive power compensation technology to explore the existing power resources potential, is a kind of effective measures to improve power quality, the traditional reactive power compensation is through the capacitor banks compensation, but now we are facing many concerns with the traditional capacitor compensation,For example,the steps switch of capacitor banks always leads to over compensation or under compensation, capacitor slow reaction time is not enough for some fast changing loads, It cannot make a quick response in real time, such situation will lead to power quality declines and much electricity safety hazard ,Hence, how to optimize with a better optimization has been more and more important, This will need to analyze the causes of the damage of electrical components by case study.

● Case description

A sewage treatment plant, the transformer capacity is 1600KVA, system voltage is 400V, its main load is fan and pump and some other equipment, some of the loads has frequency conversion speed regulation, the existing reactive power compensation equipment capacity is 480kvar capacitor banks(40kvar * 12), but after 6 months operation, the capacitor banks cabinet has components damage problem, compensation can not be conducted normally, The PF quickly dropped to 0.89, and due to the use of frequency conversion equipment, there also comes up with current distortion,this leads to a heavy penalty from state grid.

● Reason analysis

Electrician site view analysis found that there is a serious three-phase imbalance, fuse partial fuse, power capacitor has part of the drum, we concluded that the switch time of the capacitor bank cabinet during operation process is too short, only 24S, but IEC831 stipulation is that , the voltage should come down to 50V in 60S when the capacitor switch off, While through our Electrician data analysis, the capacitor in the voltage operation, components will easily get aging, this is the key reason of the capacitor damage of traditional capacitor compensation, But how to solve this problem?

● Solution

As a leader in power quality solutions research and development, The solution proposed by Xi’an CoEpower Electric is to install a 500kvar SVG Static Var Generator with dual mode function for harmonic filtering and reactive power compensation, CoEpo SVG adopts three-level topology,ms level FPGA + DSP advanced algorithm , At a ultra fast speed of less than 10 ms, bidirectional tracking compensation from-1 to 1 according to load change, Not only can the power factor quickly increase to 0.99, Reduced the current distortion, And the real-time, dynamic, fast response, To avoid abnormal damage to the components, Make the electricity consumption system more stable and reliable.

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