Shanghai National Exhibition Center

Active Harmonic Filter

The Industry

A large number of automation equipment in commercial complex automation systems requires high quality power supply.However, a considerable part of these devices have become the harmonic distortion disturbance source of the low-voltage power supply system due to their nonlinear load characteristics.Cause distribution system pollution, harm to the surrounding communication system and even the distribution system.

Background

Commercial complex harmonic mainly has the following two sources:

The harmonic sources formed by a large number of nonlinear loads, such as elevator / escalator, water supply system pump and air conditioning fan inverter, office and computer network, UPS power supply, electronic lighting, cause voltage and current distortion of distribution system; accounting for more than 80% of the total harmonics.
Background harmonic, the public power grid itself has a certain harmonic content, transmitted from the power grid side to the distribution system.

Power Quality Problem

The load in the commercial complex system mainly includes lighting, elevator, central air conditioning, etc., among which the single-phase load equipment such as lighting mainly produces 3 harmonics, while the elevator and central air conditioning load driven by frequency converter mainly produces 5,7,11 and 13 harmonics.For the harmonic situation of commercial complex system, the best solution is to adopt active filtering technology.The active filter device adopts advanced power electronics technology to detect the harmonics in the grid in real time, generate the reverse phase compensation current through the converter, and dynamically filter out the harmonics in the grid.

Solution

The main load of Shanghai National Exhibition Center is elevator / escalator, water supply system pump and air conditioning fan inverter, office and computer network, UPS power supply, electronic lighting, etc., which produces a large number of harmonics in the process of use. According to the site situation, we configure 400A active filter cabinet, and the following is the on-site governance effect.After the YTPQC-AHF Active Harmonic Filter device treatment, the current waveform is well improved, and the harmonic current distortion rate is reduced from 34.7% to 1.5%.