Electric Power Converter Torque Control for Hybrid Vehicle Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electrical power conversion systems, particularly those using DC-DC converters, suffer from energy losses in semiconductor switching and coils, which hinder efficient power management in systems with fuel cells and batteries, especially when the motor output is small or zero.
Innovation Solution
An electrical power converter system that includes a motor torque controller, a voltage command value compensator, and a pulse generator to minimize power losses by optimizing current and voltage commands based on motor torque, rotation speed, and inductance values, allowing power distribution between a fuel cell and a battery without using DC/DC converters.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If DC-DC converters are used to control power distribution between battery and fuel cell, then power management capability is improved, but energy losses increase due to semiconductor switching and coils
Solution Approach 1:
The invention extracts and eliminates the DC-DC converter component from the power management system. By using the motor as a bidirectional power conversion device, the patent removes the separate DC-DC converter that causes energy losses, while maintaining power distribution control between battery and fuel cell through the motor controller.
Solution Approach 2:
The motor serves multiple functions: it acts as both the propulsion motor and a bidirectional power conversion device (functioning as a DC-DC converter). This multi-functionality eliminates the need for separate power conversion components, reducing system complexity and energy losses while maintaining power management capability.
2Ease of operation
If DC-DC converters are used for power conversion, then power distribution control is improved, but device complexity increases
Solution Approach 1:
The invention merges the functions of the motor and DC-DC converter into a single integrated system. The motor controller performs both motor control and power distribution management, eliminating the need for separate DC-DC converter hardware and reducing overall system complexity.
Solution Approach 2:
The motor controller is designed to perform multiple functions: motor control and bidirectional power conversion for distribution between battery and fuel cell. This multi-functional approach reduces the number of separate components needed in the system.
3Power
If motor current is increased to provide torque, then motor output is improved, but power losses in motor increase
Solution Approach 1:
The invention dynamically adjusts motor current based on actual propulsion needs. By using the motor as a bidirectional power conversion device, the system can recover energy during regenerative braking and optimize current consumption during propulsion, reducing overall motor losses while maintaining required output power.
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
An electrical power converter comprises a first direct current line connected to a first direct current source, a second direct current line connected to a second direct current source, an alternating current line connected to an alternating current motor, a controller, and a pulse generator. The controller determines a required torque of the alternating current motor. The controller also determines a voltage command value that substantially minimizes a copper loss of the alternating current motor while providing the required torque of the alternating current motor. The pulse generator generates an output voltage according to the voltage command value at the alternating current output.