CN205265254U - Novel harmonic filter - Google Patents

Abstract

The harmonic filter provided by the utility model solves the problem caused by low-frequency but especially high-frequency harmonics mainly because of the harmonics caused by the negative sequence current of the generator, so that the frequency components within a certain frequency range , but attenuates the frequency components of other ranges to a very low level or no filter, so that the equipment can withstand the frequency. It mainly includes a low-pass harmonic circuit composed of the first reactor L1 and the first capacitor C1; a high-pass filter composed of the second capacitor C2 and the second reactor L2; a single-tuned filter circuit composed of the third reactor L3 and the third capacitor C3 and the third resistor R3. Wherein the third capacitor C3 is connected to the load to be connected, and the first reactor L1 is connected to the interface A of the one-phase output terminal of the generator. Thereby reducing the harm to the user's equipment and thus reducing the investment cost of the equipment; at the same time, it absorbs the interference of low-frequency signals and high-frequency harmonics that are easily fatal. Greatly clean up the high-frequency and low-frequency harmonics generated by equipment, and generate low-frequency harmonic signals for people, thereby protecting the safety of equipment and people.

Description

A New Harmonic Filter

technical field

The utility model relates to a harmonic protector for effectively suppressing low-order and high-order harmonics generated by negative sequence currents.

Background technique

With the rapid development of new technologies and changes in social methods, more and more people require higher security and stability for equipment, and the exposure to artificial electromagnetic fields in the environment continues to increase. From the generation and transmission of electricity, home appliances, and industrial equipment to telecommunications and broadcasting, everyone at home and at work is exposed to a complex mix of electric and magnetic fields. Among them, harmonic is one of the main causes of its harm. There is no doubt that the power grid is a dynamic process. When high-power single-phase loads are connected to the power grid, single-phase and two-phase faults of the line, such as short circuit, grounding, and phase failure, cause Reactive power, active power, and harmonics caused by asymmetric current and voltage will bring many bad effects to the operation and efficiency of the power grid, and will also bring other bad effects to the electrical equipment used by other users connected to the public power grid The impact is even great, resulting in irreversible shocks and shocks, and the generation of harmonics has become a recognized pollution to the power grid.

Since the effective component of the AC power grid is a single frequency of power frequency, any component different from the frequency of power frequency can be called harmonics. Distortion produces harmonics. The main nonlinear loads are UPS, switching power supply, rectifier, frequency converter, inverter, etc.

Low-frequency electric fields can affect the human body as well as other substances composed of charged particles. People are most likely to be injured at 30 to 70HZ. When people are always in the low-frequency voltage and current environment, the harm is the frequency drop that cannot be ignored, which will reduce the user's motor speed and output, and affect the output and quality of the user's products. In addition, it will bring harm to users, and the frequency will drop, which will cause inaccurate electric clocks, increased errors of electrical measuring instruments, and malfunctions of automatic devices and relay protection.

High-frequency harmonics also cause harm to equipment, especially the advent of the microelectronics era, the continuous advancement of precision instruments and aviation fields, and higher requirements for the harmonic quality of power supplies. These high-sensitivity electronic components have program problems, restarts, and crashes that occur when high-order harmonics are running. Bring very big inconvenience to daily life and work.

Contents of the invention

The technical problem to be solved by the utility model is to provide a multifunctional harmonic filter, which can filter low-order harmonics, high-order harmonics, and monotonic harmonics; reduce harmonic interference problems and reduce the impact on electrical equipment harm caused. Solved the enterprise's expenditure and technical problems. Eliminates low-order harmonics, high-order harmonics, pulse peaks, surges, noise and other interference to electrical equipment; corrects the distorted voltage waveform due to harmonics, thereby purifying the power supply, protecting electrical equipment and preventing Equipment misoperation ensures reliable operation.

The utility model solves the above-mentioned technical problems through the following measures: the low-pass harmonic circuit is composed of the first reactor L1 and the first capacitor C1; the high-pass filter is composed of the second capacitor C2 and the second reactor L2; single tuning The filtering circuit is composed of a third reactor L3, a third capacitor C3 and a third resistor R3. Wherein the third resistor R3 is connected to the zero line connection port, and the first reactor L1 is connected to the one-phase output port of the generator.

The filter of the utility model is realized based on the LC filtering principle of the circuit theory, and includes a low-pass harmonic circuit, a high-pass harmonic circuit and a monotone harmonic circuit. A low-pass harmonic circuit composed of the first reactor L1 and the first capacitor C1 can filter signals higher than a specific frequency and allow signals lower than a specific frequency to pass through. A high-pass filter composed of the second capacitor C2 and the second reactor L2 can filter signals lower than a specific frequency and allow signals higher than a specific frequency to pass through. A monotonic harmonic circuit composed of the third reactor L3, the third capacitor C3 and the third resistor R3, which can filter signals of a specific frequency and eliminate harmonic interference of the frequency. According to the characteristics of the above three circuits, the three are used at the same time to greatly attenuate the high-frequency harmonics and low-frequency harmonics in the power supply and a specific signal interference to improve the quality of power consumption and ensure normal operation.

The utility model has the advantages of:

1. The harmonic filter of the utility model can automatically eliminate low-frequency, high-frequency harmonics, and specific frequencies, thereby protecting electrical equipment. Reduce the data and program errors of the equipment, and avoid unreasonable failures. Then improve the operating efficiency and practical life of the machine, reduce the sensitivity of the low-order and high-order harmonics to the machine, and protect the safety of the equipment.

2. The harmonic filter of the utility model eliminates the interference caused by harmonics to adjacent communication systems, improves the quality of communication, and enables the communication system to operate and work normally and reliably.

3. The harmonic filter of the utility model eliminates a large number of loads such as harmonic source frequency conversion or rectifier equipment in the circuit, and the electrical equipment is in constant change, eliminating the resonant oscillation that is easily formed in series or parallel, and avoiding overvoltage Or overcurrent harmonic oscillation, endangering the safe operation of the power system.

4. The harmonic filter of the utility model eliminates the fatal low-frequency signal to the staff, so that the staff can work safely and efficiently.

5. The reactors and capacitors used in the harmonic filter of the utility model have the advantages of low loss, high work efficiency and stable operation.

6. The harmonic filter equipment of the utility model is small in size, light in weight, easy to carry, quick to install, durable, safe and reliable.

Description of drawings

Fig. 1 is a simplified diagram of the circuit structure of the utility model.

Reference signs are as follows: L1-first reactor, C1-first capacitor; C2-second capacitor, L2-second reactor; L3-third reactor, C3-third capacitor, R3-third resistor .

detailed description

Provide the utility model embodiment below in conjunction with accompanying drawing, in order to describe the technical scheme of the utility model in detail.

As shown in Figure 1, the utility model harmonic filter includes a first reactor L1, a first capacitor C1; a second capacitor C2, a second reactor L2; a third reactor L3, a third capacitor C3 and a third resistor device R3.

One end of the first capacitor C1 is connected between the second capacitor C2 and the first reactor L1, and the other end is connected to the neutral line N; one end of the second reactor L2 is connected between the second capacitor C2 and the third resistor R3 The other end is connected to the neutral line N. The first reactor L1 is connected to the interface A of the one-phase output end of the generator. Among them, the first reactor L1 and the second reactor L2 are adjustable ultrafine crystal magnetic ring material reactors, which are made of high temperature resistant material cores. The first capacitor C1 and the second capacitor C2 , The third capacitor C3 is an adjustable diaphragm supercapacitor.

By adjusting the low-pass filter composed of the first reactor L1 and the first capacitor C1, the frequency higher than the frequency set by itself is filtered out; by adjusting the high-pass filter composed of the second capacitor C2 and the second reactor L2, it is lower than The frequency set by oneself is filtered out, and the preset frequency is kept. Through these two circuits, it is kept within a certain small frequency. After absorbing a single bad harmonic through the monotonic harmonic circuit, the circuit is improved again. The voltage and current waveforms in.

The harmonic filter of the utility model can filter low-order harmonics, high-order harmonics and monotonic harmonics; reduce harmonic interference problems and reduce harm to electrical equipment. Solved the enterprise's expenditure and technical problems. Eliminates low-order harmonics, high-order harmonics, pulse spikes, surges, noise and other interference to electrical equipment; corrects the distorted voltage waveform due to the influence of harmonics, thereby purifying the power supply, protecting electrical equipment and preventing Equipment misoperation ensures reliable operation.

Claims (3)

1. a new harmonic wave filter, joins between line end and zero line one of its access generator, comprises inner harmonic wave filterThe external security packaging of ripple device circuit and circuit, is characterized in that, this new harmonic wave filter is by low pass filter and high passWave filter and single tuning wave circuit composition; Wherein low pass filter is made up of the first reactor L1, the first capacitor C1; High pass filterRipple device is made up of the second capacitor C2, the second reactor L2; Single tuning filter circuit is by the 3rd reactor L3, the 3rd capacitor C3With the 3rd resistor R3 composition, wherein the 3rd capacitor C3 is connected with the load that will connect, one of the first reactor L1 sending and receiving motorPhase output terminal interface.

2. new harmonic wave filter according to claim 1, is characterized in that, the first reactor L1, the second reactor L2 adoptBe adjustable ultracrystallite magnet ring material reactor, this reactor is formed by exotic material coiling unshakable in one's determination.

3. new harmonic wave filter according to claim 1, is characterized in that, the first capacitor C1, the second capacitor C2 adoptBe adjustable barrier film ultracapacitor.