1. What is OBC?
Automobile OBC (On-Board Charger) is an electric vehicle charging management component that converts external AC power into DC power to charge the battery.
2. The status of the OBC industry for the past two years: the installed capacity has increased significantly, and the scale of the sector has expanded rapidly
With EV production and sales growth, OBC shipments have increased in the first half of 2021, and the installed capacity of EV OBC has reached 89% of the whole year of 2020. The installed capacity in the first half of 2022 was 2.083 million sets, a year-on-year increase of 1.1 times. Currently, the mainstream on-board chargers in China are 3.3KW and 6.6KW, while foreign companies such as Tesla use high-power chargers with a power of 10KW. According to the data of the China Automobile Association, it is predicted that the sales volume of EVs in China in 2022 will be 5 million, and the market size of EV OBC in 2022 will be about 15 billion RMB.
Data from Zhiyan Consulting (China’s professional industry consulting service platform)
3. Development of OBC in the future
The output power of the vehicle-mounted OBC installed in the mainstream models in the current market has been upgraded from 3.3kW to 6.6kW. In the future, the vehicle-mounted OBC will develop in the direction of power level upgrade, size miniaturization, two-way conversion, and integration. The vehicle-mounted charger with an output power of 6.6kW has become the global mainstream trend and is gradually rising to 11kW and even 22kW. At the same time, various companies have developed two-in-one, three-in-one, and even eight-in-one integrated solutions. The two-in-one solution is 6.6kW OBC +1.5kW DC/DC, while the three-in-one solution is 6.6kW OBC+2kW DC/DC+PDU.
4. NTC thermistor is indispensable for the operation of OBC
In OBC, an NTC thermistor is usually installed on the radiator or heat sink to monitor the working temperature of OBC in real-time. When the power electronic device generates heat during charging or discharging, the NTC thermistor precisely detects the temperature change and prevents the battery from overcharging/ overheating or safety accidents.
The main functions of NTC thermistor in OBC:
4.1Temperaturedetecting: OBC generates heat during the charging process. If this is out of control, the overheating internal temperature of the charger will damage or affect the charging efficiency. The NTC thermistor can detect the charger’s temperature changes in real-time.
4.2 Temperature control: When the NTC thermistor detects that the charger’s internal temperature exceeds the preset safety threshold, it immediately sends a signal to the control system. After receiving the signal, the system takes a corresponding reaction, such as reducing the charging power, suspending charging, or starting the cooling system, to prevent the charger from being damaged by overheating.
4.3Fault alarm and protection: During OBC operation, if an abnormal temperature occurs, the NTC thermistor analyzes the data and sounds fault alarms to prevent accidents.
Exsense developed and produced the NTC thermistor for OBC, which is a glass bead thermistor potted in a metal ring lug housing. This not only improves charging efficiency but also ensures the safety of the charging process.
5. Introduction to NTC thermistor and performance
Product picture:
Specifications:
| NO. | Material | Specifications |
| 1 | Housing | Brass with nickle plated |
| 2 | Thermistor | R25=10KΩ±1% B(25/85)=3435±1% |
| 3 | Cable | UL1332#22AWG Black |
| 4 | Cable | UL1332#22AWG Red |
Electronic characteristics:
1.Response Time: ≤16 seconds max, in water
2.Dissipation Factor : 2.8mW/℃ in still air
3..Hi-pot test：AC 1800V 2mA 1 second
4.Insulation test：DC 500V ≥100MΩ
5.Rated Power: 10mW
6.Operation Temperature Range: -30℃~200℃
Contact:
Our product can be customized according to your requirements.
Ms. Tina Tang
Exsense Sensor Technology Co., Ltd
Tel:86-15813344362
email:sak@exsense.net
Web:www.exsense.net;www.exsense.com
Add:Xida Science Park, Duanzhou Dist., Zhaoqing , Guangdong
