SHAPF Series Smart Zero Sequence Current Controller

Product introduction

SHAPF series neutral current management device currently has a variety of capacity products ranging from 20A to 600A. Multiple products of the same specification can also be combined in parallel to form a larger capacity, fully meeting the neutral harmonic current management needs of various large and medium-sized loads .

Feature

1. From the perspective of the whole system, the third harmonic current is managed, and the third harmonic current on the phase line and neutral line of the entire power supply system is synchronously eliminated, and all equipment on the power distribution system can benefit.

2. It only needs to be connected in series to the neutral line or phase line, or connected in parallel, and the wiring is simple and convenient.

3. Proprietary zero-line simulation technology is used to maintain stable filtering when unbalanced fluctuations occur in the three-phase load.

4. The management device has a high degree of automatic control performance that is immediately effective when connected and used, and does not require additional control systems and complex manual adjustments.

5. Simultaneously filter out more than 90% of the 3rd harmonic current on the neutral line and phase line, reducing the electrical fire hazard caused by the 3rd harmonic current.

6. Equipped with a residual neutral current monitoring system to comprehensively monitor the residual neutral current:

7. Complete set of devices is designed with a bypass switch. Under special circumstances, the filter can be quickly short-circuited through the bypass to ensure that the load equipment continues to operate reliably.

Product Description

SHAPF series neutral current management device can eliminate current in the neutral line. With the development of urban commercial complexes,more and more nonlinear loads like LED energy-saving lamps, LED displays, etc. which are using the rectifier  of single-phase diodes are widely used in the city life.

These equipment inevitably brings serious odd-order harmonic currents to the power grid covering 3rd, 5th, 7th, 11th and other harmonics, among which

3rd harmonic is dominant. When 2 current waves flow through each phase, 6 current waves flow through the neutral line, which is equivalent to 3 times

to the fundamental current. Therefore, the neutral line current will increase abnormally and exceed the phase line current. In many cases, the neutral line current will increase abnormally to about 2 times the phase line current, which will also cause problems for low-voltage distribution.

Working principle:

The modular zero-sequence current controller is connected in parallel in the power grid system. It detects the load current in the power grid in real time through an external CT. Its DSP/FPGA/CPLD chips and the latest fast zero-sequence harmonic extraction technology to quickly analyze the load zero line current content. After this, it generate PWM pulses according to the set value, drive a bidirectional converter composed of three-level IGBT modules, and generate a compensation current that meets the requirements of the power grid. It can finally realize the compensation of the neutral line current and improve the quality of power supply.

Effect:

SHAPF series neutral current management device are as follows:

1. Reduce the neutral current by more than 90% to avoid overheating of cables and wires;

2. Avoid electrical fires caused by short circuits in neutral cables due to overcurrent

3. Avoid harmonic interference on precision equipment (such as computer crashes) and unnecessary losses;

4. Avoid the tight effect of the third harmonic on the three-phase asynchronous motor, which may cause the motor to burn out;

5. Avoid zero sequence protection malfunctions and eliminate economic losses caused by malfunctions

Model Selection