Purpose and Scope of Application

After the parallel capacitor bank installed in the substation is out of operation, it must have a discharge device to release the internal charge. For the capacitor bank that implements automatic control switching, it is even more required to release its charge below the safe voltage within the specified time. Therefore, installing dedicated discharge coils is a necessary technical safety measure for parallel capacitors in substations.

Considering the safety and reliability of parallel capacitor banks and their supporting equipment during operation, it is recommended to use a widely adopted single star wiring method for capacitor banks. The discharge coils are directly connected in parallel with each phase capacitor, and the secondary windings are connected in an open triangle shape, forming an unbalanced voltage protection circuit with the protection relay as internal protection for the capacitor. If any component inside a capacitor of any phase in the capacitor bank is damaged or faulty, it is required that the unbalanced voltage protection can detect and activate the switch to promptly disconnect the capacitor bank from the power grid. At this time, the discharge coil must have a sufficiently high accuracy level to ensure the implementation of this protection performance

Structure and performance characteristics
1. The product adopts an imported epoxy resin vacuum casting structure, achieving oil-free and completely eliminating the characteristics of oil leakage, environmental pollution, and flammability.
2. The structure is simple and the installation and use are very convenient.
3. The product maintenance is simple, just wipe off the surface dust during power outage maintenance.
4. Strengthening the internal and external insulation makes the product highly safe.
5. Using a special formula, the product is sturdy and reliable, with high mechanical strength, and can be used for a long time in various environments without cracking or breaking.  

Main technical parameters of FDGR-35kV series dry discharge coil

Connection method with capacitors

Ordering Notice
1. Rated voltage and frequency of the system
2. Voltage between the primary terminals of the discharge coil
3. Capacity of the capacitor matched between the primary terminals of the discharge coil
4. Secondary rated voltage, load and accuracy level of discharge coil

FDGR-35kV series dry-type discharge coil appearance and installation dimension diagram

FDGR-35kV series dry discharge coil