Application of intelligent capacitor

In recent years, with the continuous development of China's power industry, a large-scale high-voltage transmission network is gradually formed. Of course, the requirements for reactive power of power grid are more and more strict at the same time of development. The unbalanced reactive power of the power grid will lead to the huge fluctuation of the system voltage, and even lead to the damage of the electrical equipment.

For traditional reactive power compensation, there are triangle power capacitor, special contactor for switching capacitor, thermal relay and protection fuse, low-voltage reactive power compensation controller and other components. It is assembled in the cabinet. The cabinet is huge in volume, complicated in internal wiring, time-consuming and laborious in installation and wiring, and inconvenient in maintenance. At the same time, it is not conducive to production, transportation, installation, commissioning and reliable operation. All capacitors can only be switched on by one controller. However, when the controller is damaged, the whole device will stop working, so the hidden danger of bottleneck effect of the controller is relatively increased. It is very urgent to develop new intelligent capacitors.

The new intelligent capacitor is a split structure, which is composed of intelligent measurement and control, switch, protection and other units on the top, and one or two (delta connection) or one (star connection) low-voltage power capacitors on the bottom. The upper and lower modules can be quickly assembled and disassembled, which is very convenient for maintenance. There are two kinds of comprehensive modules: common compensation and separate compensation, which can be used by a single unit or by a network of multiple units to form a compensation system. Reactive power compensation can only be combined by selecting several modules according to the total supplementary capacity of the system. Production and use are extremely simple. By using "zero crossing switching" technology, the capacitor can be switched without inrush current, voltage and arc, and it can meet the demand of compensation in three-phase unbalanced situation.

The new intelligent capacitor has the following remarkable characteristics:

1. It can be compensated independently or in parallel

2. It can be supplemented, divided or mixed

3. Compensation capacity multiplied

4. Eliminate controller bottleneck effect

5. Advanced technology of zero crossing switch

6. With harmonic suppression function