Electronic Energy Management System: Battery Management and Generator Control

With the development of automobile technology, more and more in-vehicle electronic and entertainment facilities are installed. These electronic systems increase the pressure on vehicle energy. Under normal circumstances, when the power consumption is 1kW, 0.7 to 1.2L is consumed for every 100km of driving.

With the development of automobile technology, there are more and more electronic and entertainment facilities on board. On the one hand, these electronic systems increase the pressure on vehicle energy. Generally speaking, when the power consumption is 1kW, 0.7 to 1.2L of gasoline is consumed for every 100km, and energy is facing an increasingly scarce situation; on the other hand, the failure of the electronic system to start the car has become the main reason for the failure of starting.

At the same time, the number of cars is still increasing, and emission pollution has become one of the most concerned issues in the world. At present, Europe has issued regulations on limiting CO2 emissions. According to the regulations, from 2012 to 2015, the CO2 emissions of cars must be reduced from the current 160g/km to 120-125g/km. It is expected that by 2020, the CO2 emissions of cars will not exceed 95g/km. This regulation requires car manufacturers to consider reducing CO2 emissions when designing future cars, otherwise they will face high fines. Therefore, we are in urgent need of finding solutions to reduce CO2 emissions and save energy.

Bosch Automotive Electronics Division has been committed to the research and development and matching of electronic energy management systems. Bosch's electronic energy management system consists of components such as battery sensors, controllable AC generators and main control units with integrated electronic energy management software.

Battery status detection and charge and discharge optimization

The electronic energy management system is used, and the battery status monitoring algorithm integrated in the battery sensor can monitor the battery status in a timely manner. Accordingly, the battery and sensor working strategies can be set in the control system of the main control unit, and the battery working range can be set. According to the current battery charging status, battery temperature and vehicle driving conditions, the corresponding strategy can be used to control the generator. Charge the battery in time. In this process, the energy supply of the whole vehicle is in a completely closed-loop control state, thereby ensuring the energy supply of the whole vehicle, optimizing the energy management of the whole vehicle, ensuring the minimum current required for the engine to restart , and avoiding the problem of the vehicle being unable to restart due to battery collapse.

Generator operation Voltage Dynamic control

At the same time, the electronic energy management system can also use the controllable AC generator to dynamically change the generator's operating voltage setting to optimize the engine torque distribution and vehicle energy management.

Traditional generator control cannot utilize excess mechanical energy, and the operating voltage is also uncontrollable. When a car is accelerating and requires higher torque, the traditional generator will still consume a large amount of engine torque, while the electronic energy management system can dynamically control the generator operating voltage to adjust the generator's torque demand and optimize the torque demand during the car's operation. When the car is accelerating, the system reduces the generator's operating voltage, thereby reducing the torque demand of the generator torque, so as to ensure that more energy is provided to the car to accelerate. On the contrary, when the car is decelerating, the generator voltage can be increased so that the system can use the excess mechanical energy during deceleration to charge the battery.

Under normal battery charging and discharging conditions, if the sensor detects that the battery is undercharged, the main control unit will increase the generator operating voltage accordingly to improve the generator charging efficiency and perform rapid charging. When the battery is saturated, the generator voltage will be lowered accordingly to keep the generator in an idling state to avoid unnecessary overcharging of the battery, thereby reducing the torque consumed. This can reduce fuel consumption and keep the charging state within a safe level range, ensuring that the battery operates in a benign range and extending the battery life.

Conclusion

In summary, the electronic energy management system has, to a certain extent, improved the vehicle's starting performance, ensured the reliable supply of power in the vehicle , improved the reliability of the electronic system, reduced fuel consumption and CO2 emissions, and is increasingly being used in the development of new vehicles. Bosch is currently continuing to further optimize and conduct new research on the electronic energy management system.