The applicatoin of high voltage DC contactor in PDU
The applications of high-voltage relays/contactors are very extensive, such as the hot PV market in previous years. And now new energy vehicles market, such as electric vehicle, DC charging station/piles, plumbing PTC chargers, wind-heat PTCs, power batteries, high-voltage boxes, electric air conditioners, energy storage ESS etc, in which high voltage contactors and fuses are used as partners.
Let’s take a look at the high-voltage power distribution box, referred as the PDU (Power Distribution Unit), the high-voltage power distribution unit in the solution of new energy vehicle. The high-voltage components are electrically connected through the busbar and the wire harness to provide charge and discharge control, high-voltage component power-on control, circuit overload short-circuit protection, high-voltage sampling, low-voltage control, etc. for the high-energy system of the new energy vehicle to protect and monitor the operation of the high-voltage system. PDU can also integrate functions such as BMS main control, charging module, DC module, PTC control module, etc. Compared with traditional PDU, it has more vehicle function modules, which are more integrated in function, more complicated in structure, and have water cooling or air cooling. Heat dissipation structure. The PDU is flexible in configuration and can be customized according to customer requirements to meet the needs of different models of different customers. BDU (Battery Disconnect Unit) battery pack disconnecting unit, designed for the interior of the battery pack, is also a type of high-voltage power distribution box.
Brief introduction of high voltage contactor:
A high voltage contactor/relay is simply understood to be an automatic switch that uses a small current to control a large current. It plays the role of automatic adjustment, safety protection and conversion circuit in the circuit. The main purpose of the high-voltage relay control is to ensure that the battery system is powered up and down normally. When the vehicle starts, the high-voltage relay is turned on, and the high-voltage relay is turned off when the vehicle stops. High-voltage relay control belongs to automotive electrical and electronic systems, and its failure mode may cause damage to the driver’s life safety. Therefore, it should be developed in accordance with ISO26262 to meet functional safety requirements.