Zero Sequence Active Power Filter

Model Number

ZAPF

Outline

According to the rapid growth of computers & other electric machinery, the supply voltages are having zero sequence harmonic currents in the 3 phase 4 wire system. Zero sequence Active Power Filter is easy to install, at any position from secondary of transformer to the end of the load.

Traditional passive filters like, Zero Sequence Filters (ZSF) can reduce the zero sequence currents up to 80-85% when connected near by load . But when ZSFs connected far from the load, its efficiency will be reduced to 60%.

To improve the power quality, PQ Tech proposes best solution for Zero Sequence current problems, Zero Sequence Active Power Filter(Z-APF). Z-APF can reduce the zero sequence harmonic currents up to 98%, when near by Load and 95% when far from the load. Widely used in 3P4W power distribution system.

Problems caused by Zero sequence harmonics

• Malfunction of precision control
  
• Capacitor overloading and failures
  
• High current in neutral conductors
  
• Excitation of network resonance
  
• Damage to sensitive equipment
  
• Overheating of transformer, motor and cables
  
• Frequent tripping of circuit breakers by over current

Features

• Patent No.0435106 as The harmonic reduction apparatus which use the resonance of the Zero-Phase-Sequence impedance
  
• Reduce Line Current
  
• Reduce Neutral Current
  
• Meet IEEE Std.519-1992
  
• Solve Power Quality problem
  
• Compact and easy-to-install
  
• Quite operation and proper ventilation
  
• Standardized up to 3000A (based on neutral current)

Installation Effects

• The removal of zero sequence harmonic currents in the neutral
  
• Protect the cable from over current and fire hazardous
  
• Protect heating and loss of line and neutral
  
• Reduce unbalance of line current
  
• Improve power factor
  
• Reduce system loss
  
• Reducing high neutral-ground voltage caused by zero sequence harmonics
  
• Maintenance cost of other equipments will be reduced