EV Battery Heating via Motor Torque Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Electric vehicle batteries experience reduced performance in cold environments, and existing methods to heat them without costly battery heating devices are limited to channeling heat only during charging, not allowing for continuous battery temperature maintenance.
Innovation Solution
A controller unit and drive unit system that receives a battery heat request value and torque command, generating a motor command to deliver heat to the battery while maintaining the electric motor's torque level, allowing for continuous battery heating during vehicle operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If costly battery heating devices are employed, then battery temperature can be maintained at acceptable levels, but system cost increases
Solution Approach 1:
The motor is made to serve dual purposes: driving the vehicle and heating the battery. The motor's inherent resistive heating effect is utilized to warm the battery, eliminating the need for separate heating devices. The control system manages the motor operation to generate appropriate heat while maintaining driving functionality.
Solution Approach 2:
The motor is designed to perform multiple functions: propulsion during vehicle operation and battery heating during charging or idle periods. This multi-functionality reduces system complexity and cost by eliminating dedicated heating equipment while ensuring battery temperature maintenance across different operating conditions.
2Temperature
If heat is channeled to battery only during charging, then some heating is achieved, but continuous battery temperature maintenance is not possible
Solution Approach 1:
The system enables continuous battery heating by allowing the motor to generate heat during all operational phases including driving, charging, and idle periods. The control strategy ensures uninterrupted thermal management by transitioning smoothly between different heating sources and modes, maintaining battery temperature within optimal ranges at all times.
Solution Approach 2:
The heating system dynamically adapts to different operating conditions by adjusting motor operation parameters. During driving, the motor generates heat as a byproduct of operation. During charging, the system channels electrical energy to generate heat. The control system continuously monitors battery temperature and adjusts heating intensity accordingly, ensuring continuous and adaptive thermal management.
3Temperature
If motor command is adjusted to deliver heat to battery, then battery temperature improves, but motor torque output may be affected
Solution Approach 1:
The system employs periodic or phased heating strategies where the motor operates in different modes at different times. During vehicle operation, the motor prioritizes torque delivery for propulsion. During charging or idle periods, the motor transitions to heating mode where torque is less critical. This temporal separation allows the system to achieve battery heating without compromising driving performance.
Solution Approach 2:
The control system adjusts motor operating parameters such as current magnitude, frequency, and duty cycle to optimize the balance between torque output and heat generation. By modifying these parameters dynamically, the system can generate sufficient heat for battery warming while maintaining adequate torque for vehicle operation, or prioritize torque when driving demands are high.
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
Enables effective battery heating at any time, improving the operation, longevity, and functionality of electric vehicle batteries by maintaining optimal temperature levels regardless of environmental conditions.
Implementation Method 1
transmission of the motor command to the inverter facilitates delivery of heat to a battery associated with the vehicle
Data Source
AI summary
Various disclosed embodiments include illustrative controller units, drive units, and methods. In an illustrative embodiment, a controller unit includes a controller electrically couplable to an inverter and a memory configured to store computer-executable instructions. The computer-executable instructions are configured to cause the controller to receive a battery heat request value, receive a torque command, generate a motor command responsive to the battery heat request value and the torque command, and send the motor command to the inverter to facilitate delivery of heat to a battery to achieve a target temperature while also causing a motor associated with a drive unit to operate at a level of torque that corresponds to the torque command.