Compensation Voltage for Multiple-Winding Motor Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Control systems for multiple-winding motors driven by multiple power converters face instability due to inter-group magnetic coupling, leading to high current ripple and poor response, and existing methods require complex communication and configuration changes, making them inefficient and difficult to implement.
Innovation Solution
A drive control apparatus that includes a current detector, controller, and compensation amount calculator, which calculates and applies a compensation signal to one power converter based on the other, allowing for one-way communication and reducing the influence of dead time, thereby stabilizing the control system and suppressing inter-group interference.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If control is performed by separating mean value and differential value of each winding group, then current imbalance is eliminated and torque ripple is reduced, but the configuration of current control system must be changed corresponding to each motor, requiring specification changes of power converter
Solution Approach 1:
The patent changes the control parameter from separate mean and differential current control to a unified compensation voltage approach. By calculating compensation voltage based on differential current and adding it to the voltage command, the system achieves current balance without requiring fundamental configuration changes to the power converter specification.
Solution Approach 2:
The patent introduces a compensation voltage as an intermediary element between the current control and power converter. This compensation voltage mediates the interaction between winding groups, allowing interference compensation without direct modification of the power converter configuration or control system architecture.
2Reliability
If noninterference compensation is performed by compensation control device calculating compensation voltage from differential current, then inter group interference is compensated, but two-way communication is required between control devices which increases system complexity
Solution Approach 1:
The patent applies asymmetry by designating one control device as the compensation control device that performs calculation, while the other serves as the reference. This asymmetric arrangement eliminates the need for two-way communication, as only the compensation control device needs to calculate and apply the compensation voltage based on differential current from the reference device.
Solution Approach 2:
The compensation control device performs self-service by autonomously calculating the compensation voltage using the differential current signal. It independently determines the interference compensation amount and applies it to its own voltage command, eliminating the need for complex bidirectional communication protocols between control devices.
3Loss of time
If main control device performs calculation in advance and communicates to vice control device, then control coordination is achieved, but communication from vice control device to main control device cannot be performed
Solution Approach 1:
The patent extracts the compensation calculation function from the main control device and concentrates it in the compensation control device. This extraction allows the compensation control device to perform real-time differential current calculation and compensation voltage generation independently, eliminating communication requirements while maintaining control coordination.
4Power
If multiple power converters are used to drive multiple winding groups, then motor capacity and torque are increased, but magnetic coupling between winding groups generates inter group interference that deteriorates control performance
Solution Approach 1:
The patent converts the harmful effect of magnetic coupling into a beneficial compensation mechanism. By calculating the differential current between winding groups and generating compensation voltage proportional to this differential, the system uses the interference signal itself to create the compensation needed to cancel the interference, thereby maintaining high power output while eliminating control deterioration.
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
The solution effectively stabilizes the control system and suppresses inter-group interference even with one-way communication, resulting in a simpler configuration and improved control performance for multiple-winding motors.
Implementation Method 1
a current detector which detects a current value of the winding group
Implementation Method 2
a controller which controls the power converter for driving the winding group based on a current deviation between the current value of the winding group
Implementation Method 3
a compensation amount calculator which calculates a compensation signal by using a signal of the controller, and applies the compensation signal to one power converter
Data Source
AI summary
In a drive control apparatus for a multiple-winding motor including a power converter for driving a winding group per each winding group of a multiple-winding motor having a plurality sets of winding groups, a compensation amount calculator obtains, by using a signal of a first controller controlling a first power converter driving a first winding group among the winding groups, a compensation amount for compensating a signal of an other controller controlling an other power converter other than the first power converter, based on the compensation amount obtained by the compensation amount calculator. A signal of the other controller is compensated to control the other power converter, and the first power converter is controlled without compensating a signal of a first controller.