Description
GY-AHF-SiC SiC-based Active Harmonic Filter — Overview
The GY-AHF-SiC is a SiC-based active harmonic filter built around silicon carbide (SiC) power devices for AC220V/380V systems. It filters 2nd–50th order harmonics with a ≥95% compensation rate and <40ms response, reaching peak efficiency above 98.5%. A single cabinet accommodates up to 8 modules for a maximum capacity of 1200A, and adds neutral line zero-sequence current filtering up to 3× the phase line current, making it suited to data centers, commercial buildings and industrial sites with heavy nonlinear loads.
Working Principle
The unit connects a voltage source converter (VSC) to the power grid in parallel through a filter. By detecting the load current in real time, it separates harmonic currents order by order based on a specified-order harmonic current detection algorithm. Control signals are generated according to the set filtering percentage, driving the IGBT stage to output a compensation current with the same amplitude but opposite phase to the load harmonic current, achieving harmonic cancellation at the point of connection.
Key Features
- SiC power devices — higher voltage withstand simplifies thermal and EMC design and improves reliability.
- DSP+CPLD full-digital control core — three-level topology, advanced harmonic detection algorithm and PWM control strategy.
- Reduced module losses — peak efficiency up to 98.5% or higher.
- High power density modular design — up to 8 modules per cabinet, maximum capacity 1200A, easy installation and maintenance.
- Higher switching frequency control — reduces output ripple current and improves dynamic response.
- Harmonic compensation — rate ≥95%, 2nd–50th order with individually adjustable compensation rate.
- Unbalance compensation — unbalance degree after compensation ≤5%.
- Neutral line filtering — zero-sequence current capacity 3× that of the phase line.
- 100% current-limiting output — supports long-term stable operation.
- Selectable modes — harmonic compensation only, or harmonic + three-phase unbalance compensation.
Protection
Comprehensive protection covers overload, software/hardware overcurrent, grid overvoltage/undervoltage, grid voltage unbalance, power supply failure, overtemperature, frequency anomaly, short-circuit and resonance protection. The unit withstands 1.2 times rated overload for 60 seconds, with overall efficiency ≥97%.
Installation
Rack-mounted (rear cable entry) and wall-mounted (top cable entry) configurations are available with forced air cooling. The standard protection rating is IP20, with IP54 available on request. Suitable operating conditions include altitudes below 2000m (derating per GB/T 3859.2 above 2000m), ambient temperatures of -10°C to +50°C (derating ≤30% above 40°C), and relative humidity ≤90% without condensation.
Applications
- Data centers, hospitals and office buildings with heavy loads and high neutral currents
- Industrial plants with variable frequency drives, rectifiers and welding equipment
- EMC-sensitive environments such as broadcasting, laboratories and precision manufacturing
- Photovoltaic, wind power and energy storage systems requiring harmonic and unbalance compensation
