Four-Wheel Drive Boost Control Under Converter Power Limits
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing four-wheel drive systems in electric vehicles require increased output from voltage boosting devices or larger batteries to ensure driving performance, leading to increased cost and size, posing a challenge in optimizing power drive and recovery without exceeding rated power limits.
Innovation Solution
A control method for a four-wheel drive system with boosting operation that includes parallel-connected front and rear wheel drive units, where the front wheel drive unit has higher output power than the rear wheel unit and the voltage boosting device, ensuring power flow through the boosting device does not exceed its rated output, thereby reducing the size and cost of the system.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If the voltage boosting device output is increased to ensure driving performance, then the driving performance is improved, but the size and cost of the voltage boosting device and battery increase
Solution Approach 1:
The four-wheel drive system is segmented into front wheel drive unit and rear wheel drive unit with different power outputs. The front wheel drive unit is configured with higher output power than the rear wheel drive unit, allowing the voltage boosting device to operate at reduced capacity while maintaining overall driving performance. This segmentation enables the system to achieve required driving performance without requiring the voltage boosting device and battery to be oversized.
2Power
If the voltage boosting device output is increased to ensure driving performance, then the driving performance is improved, but the cost of the system increases
Solution Approach 1:
By segmenting the drive system into front and rear wheel units with differentiated power requirements, the voltage boosting device can be sized according to the actual power needs of the front wheel drive unit rather than the total system power. This reduces the cost of the voltage boosting device and battery while maintaining adequate driving performance.
3Loss of energy
If the output power of front wheel drive unit is set higher than rear wheel drive unit, then the power flow through voltage boosting device is reduced, but the system becomes more complex
Solution Approach 1:
The system applies local quality by assigning different power output characteristics to different parts of the drive system. The front wheel drive unit is configured with higher output power than the rear wheel drive unit, creating an asymmetric power distribution that reduces the power flow through the voltage boosting device and minimizes system losses. The control method manages this asymmetric configuration through coordinated control of the two drive units.
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
This approach reduces the size and cost of the voltage boosting device and battery, minimizes cable diameter, and optimizes energy flow, reducing fuel consumption and system losses.
Implementation Method 1
a voltage boosting device; The front wheel drive unit is connected to the battery via the voltage boosting device
Data Source
AI summary
A four-wheel drive system with boosting operation includes: a battery; a voltage boosting device; a front wheel drive unit connected parallel to the battery via the voltage boosting device and including a first motor generator and a first inverter; and a rear wheel drive unit connected parallel to the battery bypassing the voltage boosting device and including a second motor generator and a second inverter. An output power of front wheel drive unit is higher than an output power of rear wheel drive unit, and the output power of rear wheel drive unit is higher than a boosted output power of voltage boosting device. The control method of four-wheel drive system with boosting operation includes controlling the front and rear wheel drive units such that an output power flowing through the voltage boosting device does not exceed a rated boosted output power of voltage boosting device.