Axial Gap Motor Inverter Layout for Balanced Regenerative Current
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In electric vehicles with multiple double-stator axial gap motors, regenerative power efficiency decreases due to unequal regenerative power currents across motors, especially when deceleration occurs during low-speed or medium-speed travel.
Innovation Solution
The motor drive system includes double-stator axial gap motors with inverter circuits connected in series and step-up/step-down circuits to adjust voltage, ensuring equal regenerative power currents across all motors and optimizing regenerative power efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If inverter circuits are connected in parallel to battery for multiple drive motors, then each motor can be independently controlled, but regenerative power currents become unequal across motors causing efficiency decrease
Solution Approach 1:
The patent connects inverter circuits in series instead of parallel, merging their electrical paths so that the same regenerative power current flows through all inverters. This series connection ensures equal current distribution across multiple motors during regenerative braking, resolving the efficiency loss caused by unequal currents while maintaining independent motor control capability through the control device.
2Adaptability or versatility
If step-up/step-down circuits are added to adjust regenerative voltage, then voltage matching with battery is improved, but device complexity increases
Solution Approach 1:
The patent employs a single step-up/step-down circuit that serves multiple functions: it adjusts regenerative voltage to match battery charging requirements and simultaneously handles power distribution for multiple series-connected inverters. This multi-functional approach achieves voltage matching capability without proportionally increasing device complexity, as one circuit performs what would otherwise require multiple separate voltage regulation systems.
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 configuration prevents a decrease in regenerative power efficiency by ensuring equal regenerative power currents across all motors, effectively charging the battery while maintaining high efficiency during deceleration.
Implementation Method 1
The inverter circuits are configured to control power running drive and regenerative drive of the double-stator axial gap motors. The step-up/step-down circuits are configured to adjust at least voltage of regeneratively generated power of the double-stator axial gap motors.
Data Source
AI summary
A motor drive system includes a battery, double-stator axial gap motors, inverter circuits configured to control power running drive and regenerative drive of the double-stator axial gap motors, step-up/step-down circuits configured to adjust at least voltage of regeneratively generated power of the double-stator axial gap motors, and one or more control devices configured to control drive of the inverter circuits and the step-up/step-down circuits. Each of the double-stator axial gap motors includes two stators. Each of the inverter circuits are connected to a respective one of the two stators. The inverter circuits are connected in series. A single step-up/step-down circuit among the step-up/step-down circuit is provided for each of the axial gap motors. The single step-up/step-down circuit provided for each of the axial gap motors is connected to one of two inverter circuits connected to the two stators among the inverter circuits.