1.Overview
Most of the medium-voltage systems in China's urban power grids and industrial and mining enterprises are neutral ungrounded(i.e.,low-current grounded)systems.When a single-phase grounding occurs in such systems,the power grid can operate with faults;however,when the single-phase grounding fault capacitive current is large and cannot self-extinguish,the grounding arc will develop into intermittent extinction and reignition,causing arc grounding overvoltage,which endangers the insulation of electrical equipment and poses great harm to power supply and consumption equipment;it may even rapidly develop into an interphase short circuit,causing line tripping and power supply interruption.The use of intelligent arc suppression coil grounding method can accurately measure the grid capacitive current,implement rapid automatic compensation for the grid grounding capacitive current,effectively suppress the harm of arc grounding overvoltage,reduce the grounding point current,and achieve the purpose of automatically extinguishing the arc.
Baoding Enoer Electric Equipment Co.,Ltd.produces the ENR-XHBZ intelligent arc suppression coil grounding compensation device for the neutral grounding system via arc suppression coil in the power system.The device is primarily used in 6kV,10kV,and 35kV power grids to achieve neutral grounding via arc suppression coil.The device can automatically track changes in grid parameters,measure capacitive current,adjust compensation current,and operate flexibly.It can effectively suppress arc grounding overvoltage,broken line overvoltage,and transferred overvoltage.In the event of a ground fault in the grid,the device automatically alarms and features a remote output port for communication with the host computer.The device is characterized by fast response,high accuracy,and no crashes,making it the preferred grounding electrical equipment for medium-voltage distribution networks.
II.Product Model and Technical Parameters
III.Tuning method and working principle
The function of the arc suppression coil is to provide inductive current and compensate for grounding capacitive current when a single-phase grounding fault occurs in the power grid,thereby reducing the grounding current and slowing down the recovery voltage speed across the fault phase grounding arc,achieving the purpose of extinguishing the arc.According to different inductance adjustment methods,arc suppression coils can be divided into:turn adjustment type,bias magnetic type,capacitance adjustment type,etc.According to the operation mode,they can also be divided into pre-adjustment type and on-demand adjustment type.
Working Principle:
IV. Ordering Instructions
1. The adjustment method of the arc suppression coil,
2. System operating conditions, voltage level, system frequency,
3. Arc suppression coil capacity,
4. Capacity of grounding transformer.
