ISG Motor Voltage Control After Power Battery Disconnection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The driving safety of a vehicle is compromised when a power battery fails, particularly due to a third-level fault causing unstable direct current bus voltage, which can damage high-voltage components and lead to abnormal operations.
Innovation Solution
A method and apparatus that control the vehicle by reading the fault level of the power battery, determining the operating mode of the engine and ISG motor, setting the target charging power to 0, performing rotational speed and voltage closed-loop controls, and disconnecting the power battery from the high-voltage circuit to supply power to the traction motor via the ISG motor.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the power battery is used as a standby power energy storage to replace the failed power battery function, then the driving safety of the vehicle is ensured, but the complexity of the system and the cost of production and research and development are increased
Solution Approach 1:
The power battery system is designed to perform multiple functions: normally it serves as the primary power source for the vehicle, and when a third-level fault occurs, it automatically transitions to a standby role while the first power battery takes over. This multi-functionality eliminates the need for a dedicated standby battery, reducing system complexity while maintaining driving safety.
Solution Approach 2:
The control apparatus automatically detects the third-level fault in the power battery and autonomously switches the operating mode of the first power battery and ISG motor to series mode. The system self-manages the transition without requiring external intervention or additional standby components, thereby reducing system complexity while ensuring continued safe operation.
2Stability of the object's composition
If the target charging power of the power battery is set to 0 and rotational speed closed-loop control is performed on the ISG motor, then the actual torque of the engine is controlled to gradually decrease, but the complexity of the control system is increased
Solution Approach 1:
The control apparatus implements rotational speed closed-loop control on the ISG motor by continuously monitoring the actual rotational speed and comparing it with the target rotational speed. The control system adjusts the charging power based on this feedback, ensuring the actual torque of the engine gradually decreases in a controlled manner while maintaining DC bus voltage stability.
Solution Approach 2:
The control system dynamically adjusts the target charging power of the power battery based on the operating conditions. By setting the target charging power to 0 and implementing closed-loop control, the system adaptively manages the transition of torque and power distribution between the engine and ISG motor, maintaining stability while managing control complexity through dynamic parameter adjustment.
3Object-affected harmful factors
If the power battery is disconnected from the high-voltage circuit when the actual torque of the engine is less than 0 and the current of the direct current bus is less than the current threshold, then the damage to high-voltage components is prevented, but the productivity of the vehicle is reduced
Solution Approach 1:
The control apparatus monitors the actual torque of the engine and current of the DC bus in real-time. When the actual torque is less than 0 and the current is below the threshold, the system proactively disconnects the power battery from the high-voltage circuit before damage can occur to high-voltage components. This preliminary protective action prevents harmful effects while the system transitions to an alternative power configuration.
Solution Approach 2:
The ISG motor acts as an intermediary during the transition when the power battery is disconnected. It continues to provide necessary power to the DC bus by operating in a different mode, thereby maintaining vehicle productivity while the power battery is isolated for protection. The ISG motor mediates between the disconnected power battery and the high-voltage circuit, ensuring continuous power supply without damaging components.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Ensures safe vehicle travel by stabilizing the power system and preventing damage to components, even when the power battery fails, by gradually reducing engine torque and maintaining voltage stability through closed-loop controls.
Implementation Method 1
performing rotational speed closed-loop control on the ISG motor with a first rotational speed as a target rotational speed, wherein the power battery is connected in a high-voltage circuit, and the target charging power is used for controlling an actual torque of the engine to gradually decrease
Implementation Method 2
performing voltage closed-loop control on the ISG motor, in response to the actual torque of the engine being less than 0 and a current of the direct current bus being less than a current threshold
Implementation Method 3
the power battery connected in a high-voltage circuit... supplying power to a traction motor (TM) motor by the ISG motor
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
The present disclosure relates to the field of vehicle control technologies. Disclosed are a method and apparatus for controlling a vehicle, and a storage medium. The method includes: setting a target charging power of a power battery to 0 and performing rotational speed closed-loop control on an ISG motor with a first rotational speed as a target rotational speed in response to a fault level being a target level and a first detection result indicating that an engine and the ISG motor are in a series operating mode; controlling the power battery to be disconnected from a high-voltage circuit, performing rotational speed closed-loop control on the engine, and performing voltage closed-loop control on the ISG motor in response to an actual torque of the engine being less than 0 and a current of a direct current bus being less than a current threshold; and supplying power to a TM motor through the ISG motor. In this way, the stability of the voltage of the direct current bus can still be ensured in the case of disconnecting the power battery, thereby ensuring that the TM motor can still stably drive the vehicle to travel safely in the case that the power battery fails.