Low-loss 10kV power supply quick change-over switch device for forced current conversion

Abstract

The invention discloses a low-loss 10kV power supply quick change-over switch device for forced current conversion. The device comprises a first quick change-over switch and a second quick change-overswitch. The quick change-over switches comprises two parallel branches. A mechanical switch is arranged in one branch, and an electronic switch and a forced commutation assembly are arranged in the other branch. The forced commutation assembly is used for realizing quick switching between the mechanical switch and the electronic switch in the switch. The scheme that the mechanical switch and theelectronic switch are used at the same time is adopted, and the advantages of low loss of the mechanical switch and the advantages of rapid connection and disconnection current of the electronic switch are brought into full play. Meanwhile, the forced commutation assembly is added in the electronic switch branch, so that the whole quick change-over switch can be switched on and off without waitingfor zero passage of alternating current, the switching time is greatly shortened, and the whole switching time is also shortened.

Description

Technical field [0001] This application relates to the technical field of fast switching of power supplies, and in particular to a low-loss 10kV power fast switching device for forced commutation. Background technique [0002] With the development of modern science and technology, the improvement of productivity level also brings power quality problems to the power system. The increase of various non-linear and shock loads has caused serious pollution to the power supply system. With the promotion of technology, the requirements for power supply quality are also increasing. In particular, the voltage drop failure caused the user to be unable to operate normally, but also brought direct or indirect unpredictable economic losses. Therefore, it is urgent to improve the quality of power supply. The power fast switch is a cost-effective solution that can improve the reliability of power supply and realize the fast switching of the working power of the sensitive load. When the whole s...

AI Technical Summary

Problems solved by technology

[0003] In the traditional technology, there are several technical solutions for the fast switching switch of 10kV power supply: the first solution is that the fast switching switch adopts the traditional mechanical switch. The advantage of this solution is that the loss of the mechanical switch is very low during operation, but the disadvantage is that the mechanical switch As a result, the opening and closing time is very slow, and it is necessary to wait for the current to cross zero before breaking the current and then completing the power switch. The entire switching process takes at least 25ms at the fastest, which cannot meet the requirements of fast power switch.

The second solution is to use electronic switches for fast switching switches. The advantage of this solution is that the switching speed and closing speed of the electronic switch are very fast, and it can be switched off without waiting for the AC current to cross zero, but the disadvantage is that when the electronic device is running normally The loss is very large, and special air-cooled or water-cooled equipment is required, which greatly reduces the efficiency and reliability of the equipment

The third solution is that the fast switching switch adopts the solution of mechanical switch + electronic switch. This solution combines the advantages of the first two solutions. Although the loss is very low during normal operation, the current is first transferred from the mechanical switch to the thyristor electronic switch when it is switched off. However, the thyristor of the electronic switch cannot be turned off actively, and can only be turned off when the current crosses zero.

Therefore, although the loss of this scheme is low, the switching time will still be greater than 10ms

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