High Voltage DC Relay
High Voltage Dc Relay is an electromagnetic relay specially designed for switching high-voltage DC circuits (usually referring to those above 100V DC to several thousand volts), and its core task is to safely and reliably control the on-off of high-voltage DC loads. Compared with ordinary DC relays, high-voltage DC relays have significant improvements in arc-extinguishing capability, insulation design, and material selection, and are mainly applied in fields such as new energy, electric vehicles, and industrial power supplies.
The structure and working principle of high-voltage direct current relays:
1. Core structure
- Coil system:
It is wound with high-voltage resistant insulated enameled wire to ensure that the coil does not break down under high voltage. - Contact system:
- Multi-break point design: Multiple contacts are connected in series to disperse the arc energy (such as double break points or triple break points).
- Magnetic arc extinguishing: An internal permanent magnet or electromagnetic coil generates a magnetic field, which elongates the arc and cools it to extinguish it.
- Gas arc extinguishing: Inert gases (such as nitrogen or sulfur hexafluoride) are filled in a sealed cavity to suppress the reignition of the arc.
- Insulating material: The shell is made of ceramic or reinforced engineering plastic, and the interior uses highly insulating media such as mica sheets and polyimide.
- Sealing design: The fully sealed structure prevents the arc from oxidizing the contacts and avoids the impact of external dust or moisture on performance.
2. Workflow
- Coil energification: The DC power supply drives the coil to generate a magnetic field, which attracts the armature to close the contacts.
- Load conduction: High-voltage direct current is transmitted to the load through closed contacts.
- Coil power-off: The magnetic field disappears, the spring returns the armature, and the contacts separate.
- Arc extinguishing process:
When the contacts separate, a high-energy arc is generated. The magnetic blowing device or gas medium quickly extinguishes the arc to prevent the contacts from being burned.