a high frequency filter

Abstract

The invention discloses a high-frequency filter, which comprises a triangular wave generating circuit, a first MOS transistor, a second MOS transistor, a third MOS transistor and a fourth MOS transistor, wherein gates of the first MOS transistor, the second MOS transistor, the third MOS transistor and the fourth MOS transistor are all coupled with the triangular wave generating circuit; and the triangular wave generating circuit comprises a high-frequency buffering circuit, a waveform generating circuit and an amplification circuit. According to the high-frequency filter, a corresponding power supply can be inverted effectively according to power of an external power supply through the triangular wave generating circuit, the first MOS transistor, the second MOS transistor, the third MOS transistor and the fourth MOS transistor; through setting of the high-frequency buffering circuit, the waveform generating circuit and the amplification circuit, when a high-frequency component in the external power supply enters the filter, the high-frequency component can be effectively converted into a low-frequency component, a corresponding power supply in the case of low frequency can be inverted, the filter cost is reduced, and the high-frequency filter effects of the filter are enhanced.

Description

technical field [0001] The present invention relates to a filter, more specifically to a high-frequency filter. Background technique [0002] Over the past ten years, with the rapid development of power electronics technology, the number of high-power power electronic devices in the regional power distribution system has increased day by day, which has not only improved the efficiency and automation level of the regional industrial devices, but also brought about its power distribution system. Reactive problem. Due to the existence of inductive loads, there is a phase difference between the current and voltage in the regional distribution network, thereby generating reactive power and resulting in a low power factor. In addition, another type of problem is caused in the distribution network, that is, the three-phase unbalanced problem. The reason is that the traditional three-phase four-wire distribution transformers are mostly connected in the regional distribution networ...

AI Technical Summary

Problems solved by technology

Due to the existence of inductive loads, there is a phase difference between the current and voltage in the regional distribution network, thereby generating reactive power, resulting in a low power factor

In addition, it also causes another type of problem in the distribution network, that is, the three-phase unbalance problem

The reason is that the traditional three-phase four-wire distribution transformers are mostly connected in the regional distribution network, and the transformer capacity is less than 100kVA, accounting for about 50% of the global transformers, and these small-capacity transformers are vulnerable to seasonal single-phase loads. (such as single-phase tea frying machines, etc.), which in turn will cause low-voltage single-phase loads in the distribution network to be unable to be fully divided manually, the actual operating rate of the distributed loads will vary greatly, and the uncontrollable capacity increase of single-phase users, etc., are inevitable. Three-phase unbalance problem caused by low-voltage distribution network

[0003] Therefore, the existence of active power filters is particularly necessary. The existing active circuit filters use smart chips as the main control components, and then sample the power grid through the internal sampling circuit to achieve dynamic filtering and compensation. The function is very powerful, but because it uses a smart chip, it needs more accessories, and it also has a certain software cost, so the general cost is relatively high.

[0004] In the process of the existing grid quality processing, it is often necessary to filter out the high-frequency components in the grid to ensure the normal use of the grid quality control device. At this time, if the active power filter is used, it will appear to be overkill and increase The cost of power grid quality control is reduced, and if a single capacitor is used as the filtering effect, the filtering effect is not good enough to filter out the high-frequency components in the power grid.

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