CN209963761U

CN209963761U - Multi-harmonic passive filter structure

Info

Publication number: CN209963761U
Application number: CN201920934556.6U
Authority: CN
Inventors: 秦明旭; 朱东柏; 李建镇
Original assignee: Harbin University of Science and Technology
Current assignee: Harbin University of Science and Technology
Priority date: 2019-06-20
Filing date: 2019-06-20
Publication date: 2020-01-17
Anticipated expiration: 2029-06-20

Abstract

The utility model relates to a many times harmonic passive filter structure, including following several parts: the power supply, the balance reactor, the capacitor, the reactor and the load are composed of: through the resonance analysis calculation of specific reactor inductance value and corresponding capacitor capacitance value, constitute the filtering branch road of specific harmonic number of times, detect through the harmonic, can inspect out the higher harmonic number of times, connect multiple specific harmonic filtering branch road in parallel again and constitute the filtering circuit group, can filter many times of harmonic, the many times of harmonic problem that the nonlinear load produced has been solved, the effect of balance reactor is the degree of difficulty that reduces harmonious, and compensated the voltage and descended, the structure has the security height, long service life, convenient operation's characteristics, and certain power compensation's effect has in addition.

Description

Multi-harmonic passive filter structure

Technical Field

The utility model belongs to the technical field of the electric power passive filter technique and specifically relates to a novel many times harmonic passive filter structure.

Background

In order to ensure reliable and normal operation of the power system and improve the stability and the power quality of the power system, the harmonic waves of the power grid need to be treated. The harmfulness of harmonics has also become increasingly serious due to the rapid development of power electronics technology and its widespread use in power systems, transportation, industrial equipment and home life since the 70 s. Harmonic waves can reduce the efficiency of generation, transmission and use of electric energy, the harmonic waves cause the waveform distortion of voltage and current in an electric power system, and the harmonic voltage and the harmonic current with the same frequency can generate active power and reactive power loss of the same harmonic wave, so that the voltage of a power grid is reduced, and the capacity of the electric power system is wasted. Electrical equipment can also overheat under the action of harmonic waves, vibration and noise interference are generated, the aging of insulation is accelerated, the service life is seriously influenced, and even faults and burnout can be caused if the insulation is not controlled. In addition, the harmonic wave can also cause local series resonance and parallel resonance in the power grid, and the harmonic wave content is amplified, so that the equipment of the capacitor and the reactor is damaged. Harmonic waves can also bring problems to relay protection equipment, cause misoperation of a relay protection device, seriously threaten stable and safe operation of a power supply and distribution system, and cause unnecessary consequences. For weak current equipment such as computer networks, cable televisions and communication outside the power system, harmonic waves in the power system are coupled in modes such as conduction and electromagnetic induction, so that the systems are greatly interfered, and the harmonic waves can seriously affect communication equipment and electronic devices.

The common filtering modes are an active filtering mode and a passive filtering mode, and the passive power filter has the advantages of good safety, high reliability, simple circuit expansion structure, low manufacturing cost and low operation cost, and is widely applied to power systems.

Disclosure of Invention

The utility model aims at solving above-mentioned technical problem, and then provide a novel many times harmonic passive filter structure, its circuit expands pounces on simple structure, the practicality is high, it is complicated and can't carry out accurate filtering problem to specific number of times harmonic to improve the harmonic composition, after carrying out the harmonic analysis of circuit, through having used the reactor to establish ties with the condenser and constitute the filtering branch road of specific harmonic, multiple specific harmonic filtering branch road connects in parallel and constitutes filtering circuit group, can filter many times harmonic, the many times harmonic problem that nonlinear load produced has been solved to this filtering circuit group. The filter circuit group is connected with a balance reactor, and the balance reactor is used for reducing the difficulty of circuit harmonic debugging and compensating voltage drop.

The utility model provides a its technical problem realize through following technical scheme:

a passive power filter structure comprising: power supply, balance reactor, capacitor, reactor, load:

the balance reactor is a reactor with mutual inductance, the mutual inductance homonymous end of the reactor is connected, the balance reactor aims to provide harmonic voltage for the filtering branch circuit through circuit mutual inductance, a convenient condition is provided for circuit harmonic debugging, and in addition, a compensation effect is realized on voltage drop. The reactor and the corresponding capacitor are connected in series to form a filtering branch circuit with specific harmonic times, multiple specific harmonic filtering branch circuits are connected in parallel to form a filtering circuit group, multiple harmonic waves can be filtered, and the filtering branch circuit presents a low-resistance state after resonance, so that specific harmonic current does not flow into a power system any more, and the purpose of suppressing harmonic waves is achieved. The number and the type of multiple higher harmonics generated by the nonlinear load can be obtained by only carrying out circuit harmonic analysis on a circuit containing the nonlinear load, the number of turns of a coil can be calculated by carrying out design calculation of resonance, and the reactor inductance value and the capacitor capacitance value of a filter branch circuit are designed. By analogy, different filtering branches of reactors and capacitors are introduced for harmonic waves of different times, and then multiple specific harmonic filtering branches are connected in parallel to form a filtering circuit group. The whole device has high safety, good reliability and long service life, and filters various specific harmonic frequencies simultaneously in the working process of the filter.

The utility model discloses following beneficial effect has: firstly, the novel multiple harmonic passive filter structure not only has the characteristics of simple circuit expansion structure, easy completion, high economical efficiency, easy maintenance and good stability in operation. This novel many times of harmonic passive filter structure can carry out the filtering to many times of harmonic, has still compromise the needs of reactive power compensation and electric power system voltage control. In addition, the structure has the characteristics of simple structure, small volume, convenience in operation and high safety, and has an obvious effect on absorbing higher harmonics.

Drawings

Fig. 1 is a circuit diagram of the present invention.

In the figure: 1-power supply, 2-balance reactor, 3-capacitor, 4-reactor and 5-load.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

Detailed description of the preferred embodimentthe present embodiment is described with reference to fig. 1, which shows a novel multiple harmonic passive filter structure, including a power supply 1, a balance reactor 2, a capacitor 3, a reactor 4, and a load 5.

The concrete connection mode of the structure is as follows: the balance reactor 2 is a reactor with mutual inductance, the mutual inductance homonymous end of the reactor is connected, the balance reactor aims to provide harmonic voltage for the filtering branch circuit through circuit mutual inductance, a convenient condition is provided for circuit harmonic debugging, and in addition, a compensation effect is realized on voltage drop. The reactor 4 and the corresponding capacitor 3 are connected in series to form a filtering branch circuit with specific harmonic times, multiple specific harmonic filtering branch circuits are connected in parallel to form a filtering circuit group, multiple harmonic waves can be filtered, and the filtering branch circuit presents a low-resistance state after resonance, so that specific harmonic current does not flow into a power system any more, and the purpose of suppressing harmonic waves is achieved. The method has the advantages that as long as the circuit power quality analysis is carried out on the circuit containing the nonlinear load, the types and the number of various higher harmonics generated by the nonlinear load can be obtained, the number of turns of the coil can be calculated through the design calculation of circuit resonance, and the inductance value of the reactor and the capacitance value of the capacitor can be designed. By analogy, different filtering branches of reactors and capacitors are introduced for harmonic waves of different times, and then multiple specific harmonic filtering branches are connected in parallel to form a filtering circuit group. The balance reactor is connected with the filter circuit group, so that a harmonic voltage effect is provided for the filter branch circuit through circuit mutual inductance, and a convenient condition is provided for circuit harmonic debugging. The power supply 1 is connected with one end of the balance reactor to provide electric energy, and the load 5 is connected with the other end of the balance reactor and connected into a circuit to generate various higher harmonics.

This novel circuit of many times harmonic passive filter structure expands pounces on simple structure, and voltage and capacity can be done very big, can carry out certain reactive power compensation on the basis of carrying out the filtering, satisfies power system voltage control's needs, increases power system in active power's proportionality constant, improves power factor, reduces the line loss, also has certain inhibiting action to the unbalance of power system intermediate voltage and electric current.

While the invention has been described with reference to the accompanying drawings, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. The utility model discloses not only realized innovating and improving many times the passive filter structure of harmonic, realized moreover that the accurate filtering has been carried out to multiple specific number of times harmonic.

Claims

1. A multiple harmonic passive filter structure comprising: a power supply (1), a balance reactor (2), a capacitor (3), a reactor (4) and a load (5), it is characterized in that after circuit harmonic detection, harmonic generated by nonlinear load is analyzed, a reactor (4) and a capacitor (3) are connected in series to form a filter branch circuit with specific harmonic times, a plurality of specific harmonic filter branch circuits are connected in parallel to form a filter circuit group, and can filter multiple harmonic waves, the filter circuit group solves the problem of multiple harmonic waves generated by nonlinear load, is connected with a balance reactor (2), the balance reactor has the effects that the tuning difficulty is reduced, the voltage drop is compensated, finally, the power supply (1) is connected with one end of the balance reactor to provide electric energy, and the load (5) is connected with the other end of the balance reactor to form a loop of the power filter to work.