Technology Literature

What is the neutral point grounding of the power system?

Commonly used neutral point grounding methods for power systems are: direct neutral grounding, neutral grounding, neutral grounding via arc suppression coil (resonant grounding), and neutral grounding via resistance grounding. The grounding operation mode of the power system involves many important aspects such as the safe operation of the power grid, the reliability of power supply, and the safety of the user. In the professional and technical aspects related to power systems, overvoltage and insulation coordination, relay protection, communication and automation, electromagnetic compatibility, grounding design and many other fields, is a wide-ranging system problem.

Among them, the neutral point is connected to a resistor in series between the neutral point of the power grid and the ground. Appropriate selection of the resistance of the connected resistor not only bleeds off the energy of the half-wave after the single-phase grounding arc, thereby reducing the possibility of re-ignition of the arc, suppressing the amplitude of the over-voltage of the grid, and improving the sensitivity of the relay protection device. In order to act on the trip, effectively protecting the normal operation of the system.

In the AC grid, especially in cable-powered networks, resistance grounding is increasingly widespread.

Transformer neutral point grounding resistance cabinet is a complete set of grounding equipment including grounding transformer. It can be installed in power plant power system, substation power supply system, industrial and mining enterprise power distribution system, and realize the neutral point resistance of these power grids. Grounded system operation mode.

JYR-20S Transformer Neutral Point Tester

The test items are required for 110kV/220kV substation acceptance and maintenance testing(with corresponding tester types):

Test Object	Testing Item	Tester Type
Cable	Cable AC Hipot Testing	JYCX	Details
Cable	Cable Insulation Resistance Testing	JYM KYORITSU	Details
Transformer	Insulation Resistance of Winding	JYM KYORITSU	Details
	DC Leakage Testing in 1min	JYDHV	Details
	Winding Resistance Testing	JYR50S	Details
	Winding Deformation Testing	JYP	Details
	Turns Ratio Testing	JYT-A	Details
	AC Hipot Testing	JYCX	Details
	Short Circuit Impedance Testing	JYW6300	Details
	Dan Delta Testing	JYC	Details
	Oil Breakdown Voltage (BDV)Testing	JY6611	Details
	Oil Tan Delta Testing	GTD-61A	Details
Switchgear	Circuit Breaker/Disconnector Resistance	JYL-200B	Details
Relay	Relay Performance	JY7003G	Details
On-load	On-load Switchgear Testing	JYK-I	Details
On-load	Tap Changer Dynamic Testing	JYK-I	Details
Instrument Transformer	Current Transformer (CT)Testing	JYH-C	Details
Instrument Transformer	Potential Transformer (PT)Testing	JYH-C	Details
Surge Arrestor	Zinc Oxide Characteristics Testing	JY6800	Details
Surge Arrestor	1mA DC Reference Voltage	JYDHV	Details
Capacitor	Capacitor Current	JY6700	Details
Capacitor	Capacitor Inductance	JY6700	Details
Ground Grid	Grounding Down Lead Earth	JYD	Details

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DC winding resistance tester with 500 times tests on a single charge -JYR9310

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