The active filter is a new type of harmonic processing special equipment that adopts modern power electronics technology and digital signal processing technology based on high-speed DSP equipment. It consists of two main parts: the command current calculation circuit and the compensation current generation circuit. The command current calculation circuit monitors the current in the line in real time, converts the analog current signal into a digital signal, sends it to a high-speed digital signal processor (DSP) to process the signal, separates the harmonics from the fundamental wave, and sends the drive in the form of a pulse width modulation signal Pulse, drive IGBT or IPM power module, generate a compensation current equal to the harmonic current range of the power grid, compensate or offset the harmonic current, and actively eliminate power harmonics.
Active filters are called active filters. As the name suggests, this device needs to provide power (to compensate for main circuit harmonics). Its application can overcome the shortcomings of traditional harmonic suppression and reactive power compensation methods (traditional only fixed compensation). Realize dynamic tracking compensation, which can compensate for harmonics and reactive power.
The active filter system has a fast and complete fault self-checking function, including municipal undervoltage or overvoltage, bus overvoltage or overcurrent, fan failure, power supply overtemperature, input fuse blowout, etc. All faults pass The LCD display screen and LED operating status light send out an alarm signal, and the machine automatically adopts the corresponding operating protection system. The monitoring system can save 500 fault records to facilitate analysis of causes and elimination of faults.