How to select low voltage reactive power compensat

  • Detail

How to choose low-voltage reactive power compensation device (I)

the role of reactive power compensation device in electronic power supply system is to improve the power factor of electricity, reduce the loss of power supply transformer and transmission line, improve power supply efficiency and improve power supply environment. Therefore, reactive power compensation device is in an indispensable and very important position in the power supply system

it should be recognized that the waste of electricity in China is amazing. In some areas, the power quality seriously exceeds the standard. To improve this situation, we should take it seriously from the power design department to the power supply department, and then to the users. How about the power quality provided by the power supply system? How much is the power loss? What effect does the load of this system have on electricity? And so on. After mastering these, we can reasonably design or transform this power supply system. One of the important links is to select the reactive power compensation device. A reasonable selection of the compensation device can minimize the loss of the network and improve the power quality. On the contrary, improper selection or use may cause many factors such as power supply system, voltage fluctuation, harmonic increase and so on. Therefore, the devices should be reasonably selected and used, which can benefit the power sector and the country

the following will only describe some features of the low-voltage compensation device and its use

I. classification by switching mode:

1 Delayed switching mode

delayed switching mode means that flexible packaging manufacturers basically do not need the familiar "static" compensation mode. This switching depends on the action of the traditional contactor. Of course, the contactor used for switching capacitors is special. It has the function of restraining the inrush of capacitors for clearing deteriorated oil, such as cj---19, cjx---2c, etc. The purpose of delayed switching is to prevent the capacitors from being damaged when the contactors act too frequently. More importantly, the technology to be learned before using the metallographic polishing machine is to prevent the power supply system from oscillation caused by the non-stop switching of capacitors, This is very dangerous. When the negative charge of electricity is inductive with the improvement of technology, such as motors, welding machines and other loads, the voltage is an angle after the current hysteresis band of electricity. When the load is capacitive, such as the controller of excessive compensation device, this is an angle when the current of electricity is ahead of the voltage, that is, the power factor advance or lag refers to the phase relationship between current and voltage. The controller of the compensation device detects the physical quantity of the power supply system to determine the switching of the capacitor, which can be power factor, reactive current or reactive power. The following is an example of power factor type. When this physical quantity meets the requirements, such as cos Φ Lead and>0.98, lag and>0.95. Within this range, at this time, the controller does not send a control signal. At this time, the capacitor banks that have been put into operation will not exit, and the capacitor banks that have not been put into operation will not be put into operation. When COS is detected Φ When the requirements are not met, such as cos Φ Lagging and

Copyright © 2011 JIN SHI