The composition of EV high-voltage control system
The EV control module includes BDU, PDU, DCDC, MCU, air compressor and circulating pump controller; the load side includes drive motor, DCL, air conditioning compressor, high-pressure steering pump and air-cooled unit.
After determining the wiring harness connection principle of the high-voltage control system, the parts layout can be started. The general layout requirements of the controller are as follows:
(1) The ground clearance of the control module is generally >500mm. If it cannot be met due to space constraints, its full load height should not be lower than the minimum ground clearance requirement of the whole vehicle, and the waterproof level of components and external connectors should not be lower than IP67
(2) The control module that needs water cooling should ensure that its height does not exceed the minimum liquid level of the cooling kettle
(3) The parts scheme of the entire high-voltage system should be considered simultaneously. When arranging the control module, the fixed interface design, the position of the external high-low voltage interface and the convenience of the wiring harness design should be fully considered, and the detour of the wiring harness should be avoided as much as possible. At least 5D (high voltage wire harness diameter) + 10mm wire harness bending space is reserved in the axial direction
(4) Parts with high maintenance frequency, such as air compressors and water pumps, need to be arranged in positions that are easy to repair and debug.
(5) The control module should be kept away from the heat source as far as possible, and the gap between the surrounding fixed parts and dynamic parts should be ≥15mm
(6) The layout of the control module also needs to consider the convenience of assembly and after-sales maintenance, especially the installation of BDU and other parts that are time-consuming.
High Voltage Control System for Hydrogen Fuel Cell
After the high-voltage electricity of the hydrogen fuel cell is output to the stack DC-DC, part of it is input to the BDU to drive the vehicle, and the other part is used to drive its own accessories, including the air compressor, circulating pump, PTC, high-pressure water pump and DCL. These high-voltage components are often integrated with the fuel cell. After the fuel cell layout is completed, the initial layout of the components can also be determined.
If the vehicle space is not enough to make a complete arrangement of the integrated fuel cell, you can consider splitting some parts. The most common is the splitting and arrangement of the stack DC-DC.
High-voltage control system of the whole vehicle
The output end of the hydrogen fuel cell and battery pack is input to the drive motor after passing through the BDU and PDU, thereby driving the entire vehicle. At the same time, the BDU and PDU need to meet the electricity demand of other high-voltage components on the vehicle.