Dual-Inverter Motor Winding Reconfiguration Across Torque Ranges
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing motor-driving systems face inefficiencies in fuel efficiency and propulsion performance due to the limitations in voltage utilization rate and maximum torque, particularly when trying to cover both low-output and high-output sections with a single motor, leading to degraded fuel efficiency and performance.
Innovation Solution
A motor-driving apparatus with multiple inverters and switching devices that dynamically adjust the connection of windings based on required output, switching between Y-connected and open-end winding modes to optimize voltage utilization and reduce current requirements, using SiC MOSFETs for low-loss switching in low-output modes and Si IGBTs in high-output modes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If the number of windings of the motor is increased to increase the maximum torque, then the maximum torque is improved, but the voltage utilization rate in the low-torque region deteriorates
Solution Approach 1:
The patent applies dynamics by making the winding connection configuration changeable based on operating conditions. The system dynamically switches between Y-connection (for high torque) and open-end winding connection (for low torque) to optimize voltage utilization across different torque regions, resolving the contradiction between maximum torque capability and voltage utilization efficiency.
Solution Approach 2:
The patent changes the electrical connection parameters of the motor windings based on the required torque output. By switching the connection mode (Y-connection vs. open-end winding) and adjusting the effective number of turns, the system adapts the motor's electrical characteristics to match the torque demands, thereby maintaining high voltage utilization across the entire operating range.
2Use of energy by moving object
If the system is designed to cover a main driving point in a section with a high voltage utilization rate, then the fuel efficiency is improved, but the acceleration and propulsion performance deteriorates due to restriction on maximum torque
Solution Approach 1:
The system dynamically adjusts the winding connection configuration based on real-time torque requirements. During acceleration and propulsion phases requiring high torque, the system switches to Y-connection to maximize torque output. During steady-state cruising where fuel efficiency is paramount, it transitions to open-end winding mode to optimize voltage utilization, thus achieving both high fuel efficiency and maintained performance.
Solution Approach 2:
The patent makes the motor system universal by enabling it to perform optimally across diverse operating conditions. The same motor can deliver high torque for acceleration when needed while maintaining high voltage utilization for fuel-efficient cruising, eliminating the need for separate optimization for different driving scenarios.
3Device complexity
If a single motor is used to cover both low-output and high-output sections, then the device complexity is reduced, but the system efficiency deteriorates
Solution Approach 1:
Instead of using multiple motors or complex gear systems, the patent employs a single motor with dynamically reconfigurable winding connections. The controller switches between Y-connection and open-end winding modes based on torque demands, allowing one motor to efficiently cover both low-output and high-output sections without sacrificing system efficiency.
Solution Approach 2:
The single motor is made multi-functional through the reconfigurable winding connection system. It can operate in different connection modes to suit different output requirements, effectively replacing what would traditionally require multiple motors or complex transmission systems, thereby maintaining simplicity while achieving high efficiency across the full operating range.
Data Source
AI summary
A motor-driving apparatus for driving a motor having a plurality of windings respectively corresponding to a plurality of phases is provided. The motor-driving apparatus includes a first inverter having a plurality of first switching devices and connected to first ends of the plurality of windings and a second inverter having a plurality of second switching devices and connected to second ends of the plurality of windings. A third switching device is configured to selectively connect and disconnect points at which a number of turns of each of the windings is divided in a preset ratio. A controller is configured to adjust an on/off state of the first to third switching devices based on required output of the motor.