DC contactor working principle is to control the on-off of current in a DC circuit, mainly through the contacts in the contactor.
1. Contact Closure: When the DC contactor is energized, the contacts are closed or opened according to their default position through the solenoid coil. At this time, the current can flow from the contact at one end to the other end, completing the circuit closure.
2. Current flow: Current flows through closed contacts, thereby providing load operation.
3. Contact breaking: When it is necessary to break the circuit, the contacts are separated by the electromagnetic coil.
4. Arc generation: At the moment when the contacts are separated, the current cannot be interrupted immediately, resulting in arc generation.
5. Arc management: DC contractors need to take measures to manage the arc to prevent it from causing damage to the equipment.
6. Magnetic blowing technology: By generating a magnetic field in the arc area, the magnetic field acts on the arc, dispersing the energy of the arc and helping to extinguish it.
7. Arc extinguishing device: Some DC contactors use special devices, such as capacitors, inductors, etc., to provide additional voltage or current to quickly extinguish the arc.
Advantages of DC contactors
1. High power switching capability
DC contactor construction materials can handle high power levels. They can efficiently switch currents from tens to thousands of amps without compromising performance.
2. Durability and longevity
DC contactors can withstand harsh operating conditions, making them very durable and long-lasting.
3. Efficient control system
DC contactors control high-power DC circuits without the need for complex electronic equipment. Large currents can be easily turned on or off by using a low-power control signal to energize or de-energize the coil.
4. Security features
DC contactors all have safety features such as arc suppression magnets and arc suppression coils. Helps prevent arcing when contacts open or close quickly, reducing the risk of electrical fires or equipment damage.
Application of DC contactor in charging piles
1. DC contactors play an important role in electric vehicle charging piles. They are mainly used to control the on and off of current to realize charging and stopping of electric vehicles.
2. Current control: Controls the DC power current on and off between the charging pile and the electric vehicle battery. When the user connects the electric vehicle, the DC contactor closes, allowing current to flow from the charging pile to the electric vehicle battery to complete the charging process.
3. Battery protection: When a fault occurs, the DC contactor will cut off the current to prevent battery overcharge, over-discharge, and other abnormal conditions.
4. Charging pile control: By controlling current on and off, it helps charging piles achieve precise control of the electric vehicle charging process.
5. Electric vehicle interface management: DC contactors are also used to manage the connection and disconnection between electric vehicles and charging piles. By properly controlling the contactor status, the connection and disconnection process can be ensured to be safe and reliable.
6. Fault isolation: When the charging pile fails or requires maintenance, the design of the DC contactor can easily isolate the connection between the electric vehicle and the charging pile to ensure safe maintenance operations.