CN203243042U

CN203243042U - Capacitive load active filter

Info

Publication number: CN203243042U
Application number: CN201220740068XU
Authority: CN
Inventors: 李瑜
Original assignee: ANHUI TIPWORLD ELECTRICAL TECHNOLOGY Co Ltd
Current assignee: Anhui Onesky Power Quality Tech Co ltd
Priority date: 2012-12-28
Filing date: 2012-12-28
Publication date: 2013-10-16
Anticipated expiration: 2022-12-28

Abstract

The utility model provides a capacitive load active filter. The capacitive load active filter comprises a high-precision sensor, a signal collector, an FPGA (Field Programmable Gate Array), and a drive circuit which are sequentially connected. Preferably, the signal collector adopts an A/D sampling circuit. The capacitive load active filter makes use of the external high-precision sensor to detect the current of a load and further makes data acquired through detection transmitted to the FPGA through the signal collector. The data are then processed by the FPGA. The load is further driven by the drive circuit. The capacitive load active filter can make specific harmonic waves affecting a system isolated and thus well eliminate the harm of a harmonic wave current to the system.

Description

The capacitive load active filter

Technical field

The utility model relates to a kind of filter, specifically a kind of active filter.

Background technology

Along with coming into operation in a large number of power electronics, the harmonic wave of generation is more and more.The main harm of harmonic wave is the load of utility that increases electric power, reduce the system power factor, reduce available capacity and the efficient of generating, transmission of electricity and power consumption equipment, cause equipment waste, circuit waste and energy loss to cause reactive-load compensation capacitor resonance and amplified harmonic current, cause the capacitor group to damage maybe and can't put into operation because of overcurrent or overvoltage.Produce pulsating torque and cause motor vibration, affect product quality and electrical machinery life, because eddy current and kelvin effect make motor, transformer, transmission line etc. produce the secondary power loss and overheated, the waste electric energy also accelerates ageing of insulation.Harmonic voltage has strengthened the electric field strength of dielectric with the form that is proportional to its crest voltage, reduce service life of equipment.Zero sequence (3 doubly for several times) harmonic current can cause the center line overload of three-phase four wire system, and produces circulation in the Transformer Winding of delta connection, makes the winding current overrate, when serious even accidents caused.Harmonic wave can change the operating characteristics of protection relay, causes the misoperation of relaying protection facility, causes the automatics work disorders such as relaying protection.Harmonic wave has changed rate of change and the peak value of voltage or electric current, delays arc extinction, affects the breaking capacity of circuit breaker; Make particularly induction type electric energy meter generation error in dipping of measuring instrument; Disturb contiguous power electronic equipment, industrial control equipment and communication apparatus, affect the normal operation of equipment.

The utility model content

Thereby providing a kind of particular harmonic of can isolating, the technical problems to be solved in the utility model can reach well the harmonic carcellation electric current to the capacitive load active filter of the harm of system to the impact of system.

The utility model solves the problems of the technologies described above by the following technical solutions: a kind of capacitive load active filter, comprise the high-precision sensor, signal picker, the FPGA that link to each other successively, and drive circuit.

Preferably, described signal picker adopts the A/D sample circuit.

The utility model has the advantage of: can reach well the harmonic carcellation electric current to the harm of system thereby can isolate particular harmonic to the impact of system.

Description of drawings

Fig. 1 is the structured flowchart of the utility model capacitive load active filter.

Embodiment

See also shown in Figure 1ly, the utility model capacitive load active filter comprises successively high-precision sensor, signal picker, FPGA(Field-Programmable Gate Array, the i.e. field programmable gate array that links to each other), and drive circuit.

Described high-precision sensor is mainly finished an external voltage current signal and is sampled among the FPGA, also is simultaneously to guarantee FPGA and external isolation.

Signal picker is mainly finished and is become the analog signal conversion of outside high-precision sensor collection data-signal also the signal that collects to be delivered to FPGA simultaneously.Described signal picker adopts the A/D sample circuit.

Utilize the powerful disposal ability of FPGA, the digital signal that signal picker is brought is carried out analysis and control, thereby obtain needed impulse waveform.

The drive circuit Main Function is that the pulse signal that FPGA was processed is converted to load such as IGBT(Insulated Gate Bipolar Transistor, insulated gate bipolar transistor) drive.

The utility model utilizes outside high-precision sensor to detect load current, pass through signal picker, detecting to such an extent that data are delivered in the FPGA, isolate different subharmonic currents and phase place in the load current with FPGA by FFT and IFFT algorithm, use idle theoretical algorithm, send out in the system subharmonic different, different subharmonic are on the impact of the specific subharmonic of system in the observing system, then determine which subharmonic is larger to systematic influence, remove specific time to systematic influence during like this toward system's generating stream, make system send harmonic current with the load antiphase with the harmonic current in the bucking-out system, thereby isolate particular harmonic to the impact of system.Reach well the harmonic carcellation electric current to the harm of system.

The above is only for the preferred embodiment of the invention; not in order to limit the invention; all in the invention spirit and principle within do any modification, be equal to and replace and improvement etc., all should be included within the protection range of the invention.

Claims

1. capacitive load active filter is characterized in that: comprise the transducer, signal picker, the FPGA that link to each other successively, and drive circuit.

2. capacitive load active filter as claimed in claim 1 is characterized in that: described signal picker employing A/D sample circuit.