Hybrid power filter

Abstract

The mixed high-voltage electric filter comprises a converter-type serial filter, wherein the serial filter includes: a zero magnetic flux converter with primary winding serial connecting with the power network busbar and secondary winding forming a fundamental wave resonance loop together with a fundamental wave induction coil / capacitor. Besides, an equal potential cabinet is supported on ground by an insulation ceramic bottle. This invention overcomes defects in prior art, and has great application value.

Description

technical field [0001] The invention belongs to grid control equipment in electrotechnical technology, and particularly relates to a high-voltage power filter, which is used for suppressing harmonic current and voltage of a high-voltage and low-voltage system. Background technique [0002] The Chinese invention patent application "harmonic suppression device" with application number 02139029.0 is to form a series resonant circuit for the fundamental wave through the secondary fundamental winding, inductance coil and capacitor of the converter to realize the primary and secondary harmonics of the converter. The fundamental ampere-turn balance between them makes the converter present low impedance to the primary fundamental current and high impedance to the harmonic current, allowing the fundamental current to pass smoothly and effectively suppressing most of the harmonic current. For the remaining part of the first harmonic current, the active filtering composed of detection ...

AI Technical Summary

Problems solved by technology

This device has the following disadvantages: (1) Since the primary winding of the converter is electrically connected to the busbar of the grid, when the grid is in high voltage or even ultra-high voltage conditions, the primary winding of the converter and the iron core, and the secondary Between the windings, the electrical insulation requirements of high voltage or even extra high voltage must be met, which makes the manufacturing process of the converter complicated, high in cost, large in size and weight, and its application is limited

(2) When the power grid is in the working condition of low voltage and high current, due to the ampere-turn balance of the fundamental current of the primary and secondary windings, the secondary current increases proportionally to the primary current, and the power of the inductance coil and capacitor is very large. High price, large volume and weight, and limited applications

(3) The active filtering method composed of detection iron core, detection winding, operational amplifier, driver and harmonic winding is adopted to further offset the residual harmonic current. Since the proportion of residual harmonic current is not large, the detection iron Core, detection windings, operational amplifiers, drivers, and harmonic windings constitute an active filtering method, which has high complexity and cost, reduced reliability, and uneconomical input-output ratio.

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