Delta Active Harmonic (Power) Filter
APF Principle
Delta’s PQC Series APF is connected in parallel with non-linear loads, and uses one set of current transformers (CT) to detect the load current. It calculates each order harmonic current by FFT algorithms in its DSP microchips, and then generates a compensating current with the same amplitude but opposite phase angles to the detected harmonic current, which cancels out the original load harmonics.
The PQC series APF not only eliminates harmonic current from the load side, but it also mitigates harmonic voltage caused by harmonic currents. The APF system can also improve power factor (PF) and correct load imbalances in the power system.
Mixed Fixed Type
Rated Voltage – AC 208 V, AC 400 V, AC 690 V
Electrical Specification
Input Voltage Range
- AC 208 V AC 166~250 V, AC 166~250 V
- AC 400 V AC 308~456 V, AC 308~480 V
- AC 690 V AC 384~880 V
Electric Connection
- AC 208 V 3P4W, 3P3W
- AC 400 V 3P4W, 3P3W
- AC 690 V 3P3W
Rated Current per Module
- AC 208 V 50 A, 75 A, 100 A, 150 A
- AC 400 V 30 A, 50 A, 75 A, 100 A. 150 A
- AC 690 V 100 A
Rated Current per Cabinet
- AC 208 V
50~750 A (Module combination)
- AC 400 V
30~750 A (Module combination)
- AC 690 V
100~500 A (Module combination)
Rated Frequency
50(60) Hz ± 10%
Input Voltage THD Range
≤ 15%
Redundancy
Each module is an independent filtering system
Harmonic Elimination Range
2nd~50th order (Selectable)
Harmonic Filtering Degree
0~100% programmable per harmonic in Ampere value
Harmonic Filtering Performance
Filter up to 98% harmonics at rated load
THDv < 3%, THDi < 5% after filtering
Reactive Power Compensation Capability
Both inductive and capacitive reactive power
Reactive Power Compensation Performance
Cosφ ≥ 0.99 after compensation (if the APF capacity is sufficient)
Imbalance Correction Capability
Mitigate negative and zero sequence
Full Response Time
< 10 ms
Instant Response Time
< 100 us
Thermal Loss
- AC 208 V
≤ 5% of APF rated capacity
- AC 400/690 V
≤ 3% of APF rated capacity
Output Current Limitation
Automatic (100% rated capacity)
Parallel Expansion (System)
Up to 10 Racks (7 modules per cabinet)
MTBF
> 100,000 hours
Control Technology
Switching Frequency
30 kHz
Controller
DSP + FPGA
CT Position
Grid side or Load side
Waveform Display
Input Voltage waveform, Grid current waveform, Load current waveform and APF current waveform
Harmonic Current Histogram Display
Grid harmonic current and load harmonic current
Communication
Modbus RTU (RS-485), Modbus TCP/IP (Ethernet)
Physical Specification
IP Grade of Cabinet
IP20, IP30, IP54, IP55 or customization
Cooling Method
Intelligent forced air cooling
Noise Level
- AC 208/400 V
< 65 dB(A) @ 1 m (Module)
- AC 690 V
< 70 dB(A) @ 1 m (Module)
Dust Filter
Optional
Dimension
Please downlaod the brochure and refer to APF Model table
Weight
Please downlaod the brochure and refer to APF Model table
Environmental Requirement
Ambient Temperature
-10~50°C
Relative Humidity
0~95% (No condensation)
Altitude
≤ 1000 m (Rated Capacity), 1000-3000 m (De-rating 1% per 100 m)
Rear/ Front Connection Type
Rated Voltage
AC 400 V, AC 690 V
Electrical Specification
Input Voltage Range
- AC 400 V
AC 308~456 V, AC 308~480 V
- AC 690 V
AC 384~880 V
Electric Connection
- AC 400 V
3P4W, 3P3W
- AC 690 V
3P3W
Rated Frequency
50(60) Hz ± 10%
Input Voltage THD Range
≤ 15%
Rated Current per Module
- AC 400 V
50 A, 75 A, 100 A
- AC 690 V
100 A
Rated Current per Cabinet
- AC 400 V
50~700 A (Module combination)
- AC 690 V
100~500 A (Module combination)
Redundancy
Each module is an independent filtering system
Harmonic Elimination Range
- AC 400 V
2nd~50th order (Selectable)
- AC 690 V
2nd~31st order (Selectable)
Harmonic Filtering Degree
0~100% programmable per harmonic in Ampere value
Harmonic Filtering Performance
Filter up to 98% harmonics at rated load
THDv < 3%, THDi < 5% after filtering
Reactive Power Compensation Capability
Both inductive and capacitive reactive power
Reactive Power Compensation Performance
PF ≥ 0.99 after compensation (if the APF capacity is sufficient)
Imbalance Correction Capability
- AC 400 V
Mitigate negative and zero sequence
- AC 690 V
Mitigate negative sequence
Full Response time
< 20 ms
Instant Response time
< 100 us
Thermal Loss
≤ 3% of APF rated capacity (kVA)
Output Current Limitation
Automatic (100% rated capacity)
Parallel Expansion(System)
Up to 10 Racks (7 modules per cabinet)
MTBF
> 100,000 hours
Control Technology
Switching Frequency
- AC 400 V
60 kHz, 30 kHz
- AC 690 V
30 kHz
Controller
DSP control
Communication
Modbus RTU (RS-485), Modbus TCP/IP (Ethernet)
Physical Specification
IP Grade of Cabinet
IP20, IP30, IP42, IP54 or customization
Cooling method
Intelligent forced air cooling
Noise Level
- AC 400 V
< 65 dB(A) @ 1 m (Module)
- AC 690 V
< 70 dB(A) @ 1 m (Module)
Dust Filter
Optional
Dimension
Please downlaod the brochure and refer to APF Model table
Weight
Please downlaod the brochure and refer to APF Model table
Environmental Requirement
Ambient Temperature
- Rear connection type
-10~50°C with 100% capacity, de-rating running from 50~55°C
- Front connection type
-25~40°C with 100% capacity, de-rating running from 40~55°C
Relative Humidity
0~95% (No condensation)
Altitude
≤ 1000 m (Rated Capacity), 1000-2000 m (De-rating 1% per 100 m)
