Arc-suppression coil neutral earthing

THT-PXHK(C) system is mainly used for 6KV-66KV neutral ungrounded power grid and also widely applies to high voltage distribution networks in mining , coal , chemical industry and larger cities .

With normal grid operation, the system provides real-time monitoring of network capacitive current. When occurs single-phase grounding, it will automatically enter compensation state and implement optimal compensation for the grid capacitive current. The fault residual current will be less than 5A, which can effectively suppress the arc over-voltage, thus prevent failures arising like phases short circuit etc. The system can be customized to set for ideal state as per user requirements.

THT-PXHK system consists of three units: microcomputer control cabinet, biasing magnetic arc-suppression coil body, grounding transformer (optional to users). The grounding transformer and arc suppression coil can either dry or oil immersed. The microcomputer control cabinet is with standard screen, which includes automatic tracking compensation controller, dashboard and rectifier etc.

Electric power industry standard DL/T 620-1997 "AC electric equipment overvoltage protection and insulation coordination" provides: For the 3KV- 10KV system indirectly connect to generator and 35KV, 66KV system, when single phase ground-fault capacitive current doesn't exceed the following values, should use non-grounding method , when exceed the following values and need to run under ground-fault conditions , should use arc suppression coil grounding method:

1,3KV- 10KV overhead line System constructed by concrete or metal tower and all 35KV, 66KV system, 10A

2, 3KV-10KV overhead line system constructed by non-concrete or non-metal tower:

1) 3KVand 6KV, 30A

2) 10KV, 20A

3, 3KV-10KV cable system, 30A

1, After installation, shall carry out strict inspection on the system, to ensure everything is all right.

2, Equipment installation, wiring, test, maintenance shall be undertaken by qualified professionals, ensure no power in equipment prior to

installation.

3, Whenever occurs single phase grounding, not allowed to operate or manually adjust the arc suppression coil on the bus cable.

4, Whenever occurs single phase grounding, not allowed to switch off controller and controller AC and DC power supply.

5, Don't operate if any of following circumstances happen when turning on isolation switch between arc suppression coil and neutral point:

1) Single phase grounding happens, and sounds hum from arc suppression coil

2) Neutral point displacement voltage is greater than 50% phase voltage.

6, Single phase grounding happens, monitor and record the following data if possible:

1) Operation of grounding transformer and arc suppression coil.

2) Parameters displayed on the microcomputer screen: capacitive current, residual current, out-of-resonance degree,

neutral point voltage and current etc.

3) The start and end time about the occurrence of single phase grounding.:

4) The connection lines and single phase grounding reason.

5) Weather Conditions.