Serial-parallel mixed type filtering and protecting device of passive power

Abstract

The invention provides a serial-parallel mixed type filtering and protecting device of passive power. The serial-parallel mixed type filtering and protecting device of the passive power does not easily resonate with a system, effectively reduces total current of a system, and has an obvious energy-saving effect. The serial-parallel mixed type filtering and protecting device of the passive power comprises a first electric reactor (L1), a first capacitor (C1), a transformer (T1), a first sing-phase silicon controlled rectifier (Q1), a second single-phase silicon controlled rectifier (Q2), a first voltage dependent resistor (Y1), a second voltage dependent resistor (Y2), a current limiting reactor (L0), a lightning arrester (B1), a second electric reactor (L2), a second capacitor (C2), a third electric reactor (L3), a third capacitor (C3) and a vacuum contactor (K). According to the serial-parallel mixed type filtering and protecting device of the passive power, the serial-parallel mixed mode is adopted, the electric reactors and the capacitors are connected in series to be designed with traditional filtering branches in a mixed mode, the capacity requirement of series branches is effectively reduced, the filtering performance is improved, and meanwhile the cost is reduced. The package scheme is based on passive power elements, a protecting circuit is also based on self triggering, the reliability is high and the service life is long.

Description

technical field [0001] The invention relates to a filter device, in particular to a series-parallel hybrid passive power filter and protection device. Background technique [0002] The harmonics of the power system mainly come from nonlinear loads including rectification links such as frequency converters and intermediate frequency furnaces. With the wide application of these nonlinear loads, there are more and more harmonics in the power system, and the power quality is deteriorating day by day. Therefore, it is extremely urgent to filter the harmonics generated by these nonlinear loads. At present, there are two main schemes for filtering harmonics in power systems, one is traditional passive filtering (such as filtering with single-tuning, double-tuning and other filter circuits), and the other is using active filtering. The passive filter used in the traditional passive filtering solution has simple structure, mature technology and low investment cost, but the filtering...

AI Technical Summary

Problems solved by technology

However, it is affected by system parameters, and it is difficult to achieve the ideal filtering effect.

And when the parameters change or the matching is not good, it is easy to resonate with the system

For systems with high power factor, reactive power will be sent back to the system and cannot be put into operation

Moreover, it does not reduce, or even amplifies the harmonic current, which increases the total current of the system and has no energy-saving effect

[0004] Active filtering also cannot reduce the total current of the system. Due to the use of power electronic devices, the total loss is relatively large, and there is no energy-saving effect.

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