Automobile electronic technology is popularly applied in the application of electric automobiles,hybrid-electric vehicles, For the stable sampling and control signal, we could use isolation DC/DC converter in the automobile electronic. We will show you where the DC/DC converter is used in the automobile as follows.
2. Power modules for the BMS
The description of BMS and power requirement BMS is the heart in the battery life of electric vehicles. It achieves the function of on-line detection and real-time monitoring, which provides battery voltage, current temperature SOC and insulation status information, etc. Meanwhile, It also can real-timely identify running state of batteries and battery pack discreteness. When it fails, it will send a fault signals and give an alarm to the controller. The System structure diagram sees below:
In BMS isolation in the sampling of current, voltage, soc, temperature, etc signal, and the isolation voltage of the dc-dc converter are dependent on the number of battery cells. Besides, we should use power modules that use the material of AEC-Q100 approved. Finally, we should concern the operation temperature of the DC-DC Converter, it should be -40℃-125℃.
The description of BMS and power requirement
For the power requirement, Mornsun has promoted a new automobile degrade dc-dc converter CF0505XT-1WR2, and it has excellent parameters as follows:
● Operation temperature : -40℃-125℃
● Up to 3500VDC isolation voltage
● Satisfy with AEC-Q100 requirement
● Short circuit protection
● Low ripple and noise
3. Power modules for the motor controller
3.1 The description of the motor controller
The motor controller is the unit in charge of driving and protecting the motor. We will show you the block diagram as follows:
We need a positive/negative output voltage for turning on/off the IGBT, and the negative output voltage should less than the positive output voltage to reduce energy consumption. In this application, IGBT will have a very high DV/DT which will be a big interference to the dc-dc converter, so the dc-dc converter should have a high isolation voltage. And the motor controller is close to the motor, it should have a high operation voltage.
3.2. Mornsun power resolution for the BMS For the power requirement, Mornsun provides a dc-dc converter QA04 special designed for the automobile IGBT driver, and it has excellent parameters as follows: Operation temperature: -40℃-105℃ Up to 3000VAC isolation voltage、isolation cap low to 10pF Positive/negative output voltage 15V/-8.7V, 26% energy saved Up to 1000uF Max. Capacitive Load Start-up without overshooting Short circuit protection
3.3 Recommend product
4. The solution to Intelligent Charger Power Supply
4.1 Overview of application
The intelligent charger can control the charge current according to the battery pack charging curve in an intelligent way. During the charging process, it can achieve the equalizing charge of the battery pack, ensure that all the cells can reach the upper charge voltage limit simultaneously and minimize the nonconformity caused by the difference of the cell material, production and operation in the battery pack, which will greatly enhance the available capacity and service life of the battery pack. The intelligent charger is thus widely used for the quick charge of the electric city buses and hybrid buses.
4.2 Composition of intelligent charger system and the requirement for power supply
As shown in the above figure, the quick charge of the battery is achieved by the main charger in the early stage of charging. In general, the charge current is 30 A. However, due to the diversity of the batteries, some batteries will be fully charged first while some will be later. If the high charge current is maintained at the terminal stage of the charging, the batteries may be damaged by the overcharging. Therefore, a control board is provided to monitor the battery cell voltage in real-time through the battery monitoring unit to determine the state of the battery. When the battery is to be fully charged, the main charge power supply will be switched off and the constant-current charge will be made by the auxiliary charge power supply URB2404LD-3000. As the accuracy of battery voltage acquisition may be influenced while the auxiliary charge power supply is charging, the auxiliary power supply will, every second, be switched off twice by the remote switching-off function of Ctrl pin provided by the auxiliary power supply itself during the charge cycle. The battery voltage will be accurately monitored in the switching-off interval until the batteries are fully charged. Then the auxiliary charge power supply can be shut down. In this way, all 24 batteries can be fully charged.
4.3 Solution to Intelligent Charger Power Supply
For the power requirement, Mornsun has promoted a new automobile automotive equalizing auxiliary charge power supply URB2404LD-3000. The power solution is featured: Constant output:3A Remote control and output voltage trimming Wide input wide:9-36V Isolation 1500VDC Short circuit protection Two choices of charging voltage of lithium battery:3.3V and 3.7V
4.4 Recommended Product Automotive power supply：