Active filter device with method of energy-saving and consumption-reducing harmonic control

Abstract

The invention discloses an active power filter with a method for processing harmonic waves in an energy-saving and consumption-reducing mode, and belongs to the technical field of filtering. The structure is mainly composed of a main control display unit, a main circuit module, a converter module, an output reactor, an output filtering return circuit, a control circuit module, a control system, a zero line bar, a nonlinear load and the like. The main circuit module, the converter module, the output reactor and the output filtering return circuit are connected through a cable. The main control display unit and the control circuit module are connected through a network control cable. The nonlinear load is connected to the other end of a three-phase power grid through a cable. The active power filter is a novel harmonic wave processing device for filtering the harmonic waves dynamically, an included harmonic component is calculated in an on line mode by monitoring of real time harmonic wave conditions of the power grid, corresponding control signals are generated, harmonic currents with the same electric quantity and opposite directions are injected to the power grid, second to fiftieth harmonic waves can be fast and effectively filtered, a filtering rate can reach 97%, and the process is not affected by system impedance.

Description

technical field [0001] The invention relates to an active filter device, in particular to an active filter device with a method for energy saving and consumption reduction and harmonic control, which is applied in the technical field of electric power quality control. Background technique [0002] The active filter device is a device that needs to provide power. Its application can overcome the shortcomings of traditional harmonic suppression and reactive power compensation methods such as LC filters. The wave supplements reactive power; the theory of instantaneous reactive power in three-phase circuits is the main basic theory for the development of APF; there are two types of APF, parallel type and series type, and the former is used more; Active filtering devices are mainly used to control problems caused by voltage harmonics. Compared with the active filter device, the active filter device has a better treatment effect, and can mainly filter out multiple and high-order ...

AI Technical Summary

Problems solved by technology

[0004] At present, most of the harmonic devices on the market are passive filter devices, which have the following disadvantages: (1), it is easy to have parallel resonance with the power grid, which seriously affects the safe operation of the power grid; (2), the working efficiency of the device is not good High, it can only filter out most of the filters, and cannot provide high-quality harmonic control effects; (3), the filter capacitor is easy to attenuate, resulting in detuning of the filter branch, and losing the effect of filtering; (4), the life is not long, the best The life of the passive filter is 3 to 4 years. After the device is scrapped, the capacitor will pollute the environment; (5), the passive filter cannot be used in the occasion with high power factor, because the reactive power must be compensated at the same time as the filter, which leads to Limitations of passive filtering applications; (6) Passive filtering can only eliminate harmonics with a fixed number of times. If there are many harmonics in the power grid, the number of branches will be increased, resulting in high cost; (7) ), passive filtering cannot dynamically eliminate filtering, and cannot balance reactive power well; (8), passive filtering is greatly affected by temperature, which affects the filtering effect of the device

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