Dual-Battery Vehicle Power Control for Timed Power Addition
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In electric vehicles with combined high-capacity and high-power batteries, accurately timing the addition of electric power from one battery to another is challenging, leading to reduced performance and accelerated battery deterioration due to estimation errors and delays in power output.
Innovation Solution
A vehicle control device and method that acquires and calculates the actual output power and upper power limit values of both batteries, adjusting the power conversion process to ensure suitable timing for power addition, using a processor to determine output instructions based on actual and requested power differences and threshold values.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of time
If the amount of electric power requested from the electric vehicle is estimated, then the power management can be planned in advance, but the timing when the requested amount of electric power actually exceeds the upper power limit value of the high-capacity type battery deviates from the estimated timing due to estimation errors
Solution Approach 1:
The control device monitors the actual output power of the high-capacity type battery in real-time and compares it with the upper power limit value. When the actual output power exceeds the upper power limit value, the control device immediately issues an instruction to add electric power from the high-power type battery. This feedback mechanism eliminates timing deviations caused by estimation errors.
Solution Approach 2:
The control device pre-calculates and stores the upper power limit value of the high-capacity type battery based on its state (charge level, temperature, etc.). This preliminary preparation allows the control device to quickly respond when the power limit is reached, reducing the reaction time and improving timing accuracy.
2Productivity
If electric power from the high-power type battery is added when the high-capacity type battery output exceeds the upper power limit value, then the total electric power to the motor is maximized, but the high-capacity type battery becomes over-discharged which accelerates battery deterioration
Solution Approach 1:
The control device continuously monitors the output power of the high-capacity type battery and compares it with the upper power limit value. When the output power exceeds the limit, the control device immediately issues an instruction to add electric power from the high-power type battery. This real-time feedback prevents over-discharge by switching to the high-power battery at the optimal moment, thereby extending battery lifespan while maintaining total power output.
Solution Approach 2:
The control device acts as an intermediary that manages the power distribution between the high-capacity type battery and the high-power type battery. It determines the optimal timing for switching between batteries based on their respective states and power output levels, ensuring that the high-capacity battery is not over-discharged while maintaining sufficient total power to the motor.
3Speed
If there is a delay in outputting electric power from the high-power type battery after instruction, then the system response time increases, but the high-capacity type battery becomes over-discharged during the delay period
Solution Approach 1:
The control device pre-calculates and stores the upper power limit value of the high-capacity type battery based on its state (charge level, temperature, etc.) before power addition is needed. This preliminary preparation allows the control device to immediately issue the power addition instruction when the limit is reached, minimizing delay and preventing over-discharge.
Solution Approach 2:
The control device implements real-time monitoring of the high-capacity type battery's output power and immediately detects when it exceeds the upper power limit value. This real-time feedback triggers an immediate power addition instruction to the high-power type battery, reducing response delay and preventing over-discharge during the transition period.
Data Source
AI summary
A vehicle control device includes processor configured to execute computer-readable instructions to perform. The processor is configured to acquiring a state of a first battery and a state of a second battery, acquiring at least first actual output power of the first battery, calculating a first upper power limit value based on the state of the first battery, calculating a second upper power limit value based on the state of the second battery, and controlling a power conversion process of a power convertor based on the calculated upper power limit values, requested power from a vehicle to be output to a motor, and the first actual output power. The controlling of the power conversion process includes, when output instruction content for iteratively issuing an instruction is determined, calculating the second requested power obtained by correcting currently requested power based on a difference between previously requested power and the first actual output power.