Medium Voltage Air Core Reactors

Air Core Reactor Left Angle

HPS offers Air Core Reactors that are primarily used as current or voltage limiting devices, particularly where large currents can enter a system that uses small amounts of power.

Air Core Reactors, unlike Iron Core reactors, have no core to saturate. With no core to saturate, the impedance remains linear at all levels of current.

Types & Applications

  1. Neutral Grounding Reactors:

    A neutral grounding reactor is used for low impedance grounding of a neutral point of 3 phase systems to control single line to ground faults. It is connected to the neutral of a transformer for protection. Neutral grounding reactors are widely used in solar power applications.

  2. Inrush Current Limiting Reactors:

    Reduces transformer inrush current during start up.

  3. Short Circuit Current Limiting Reactors (CLR):

    Limits the available system short circuit current to a level that is lower than that of downstream equipment. A CLR eliminates the need to replace existing devices which a a short circuit current rating that is less than the existing available system short circuit current.

  4. Power Factor Reactors:

    Limits currents and voltage due to the connection of capacitor banks used for power factor correction.

  5. DC Smoothing Reactors:

    Smooths the ripple in DC circuits, reduces harmonic currents and transient over currents.

  6. DC Inter Phase: 
    Connected to the output of 2 parallel DC drives to suppress the circulating current among the converters as well as to absorb the difference between the voltages of parallel drives.
Product Specifications 
  • Voltage up to 46 kV
  • BIL up to 250 kV BIL
  • kVAR up to 10000
  • Max AC Current = 4000 Amps
  • Max DC Current = 6200 Amps
  • Frequency – Max 420 Hz
  • Insulation Class – 220 Co 
  • Temperature Rise 80, 115, 150 Co 
  • Enclosure Types: 1, 2, 3R and 3RE
  • Open coil for indoor installation only

* - Above ratings are subject to a combination of Current, Voltage and Reactance

Compliance and Standards

  • IEEE C57.12.01 - Standard for General requirements for Dry-Type Distribution and Power Transformers 
  • IEEE C57.12.91 - Standard Test Code for Dry-Type Distribution and Power Transformers 

  • IEEE C57.16 – Series Connected Air Core Reactors

  • IEEE C57.32 – Neutral Grounding

  • IEC 60076-6 - Reactors

  • IEC 60289 - Reactors

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