Multi-Phase Machine Control Device Using Estimated Current Decoupling

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Solution Overview

Problem

Existing control devices for multi-phase rotating machines face challenges in reducing communication load during decoupling control between two systems of arithmetic units, leading to deteriorated control capacity and increased noise susceptibility due to high communication loads and longer control cycles.

Innovation Solution

The control device employs a configuration where each system calculates an estimated current based on its own current instruction values, reducing the reliance on inter-system communication for decoupling control, thereby minimizing communication load and enhancing control efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If communication between arithmetic units is increased to obtain current information of the other system, then decoupling control accuracy is improved, but communication load increases and control cycle lengthens

Engineering Contradiction:

Improvedecoupling control accuracyVSAvoidcontrol cycle speed

Core Design Contradiction:

Measurement precisionVSProductivity

Solution Approach 1:

The patent creates a copy of the other system's current information by having each arithmetic unit calculate an estimated current of the other system based on its own current instruction values and system parameters. This estimated current serves as a substitute for the actual current information that would otherwise require communication to obtain, thereby maintaining decoupling control accuracy while eliminating communication load.

Inventive Principle:

Principle #26Copying

2Measurement precision

Engineering Contradiction:

Improvedecoupling control accuracyVSAvoidnoise susceptibility

Core Design Contradiction:

Measurement precisionVSObject-affected harmful factors

Solution Approach 1:

The patent eliminates communication between arithmetic units by having each unit independently calculate estimated current values based on its own current instruction values and system parameters. This copying approach substitutes actual current information with calculated estimates, thereby maintaining decoupling control accuracy while eliminating the communication load that causes noise susceptibility.

Inventive Principle:

Principle #26Copying

3Productivity

If a single arithmetic unit is used for both systems, then communication load is reduced, but device complexity increases and adaptability decreases

Engineering Contradiction:

Improvecommunication efficiencyVSAvoidcontrol configuration complexity

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The patent divides the control system into two independent arithmetic units, each responsible for one system. Each arithmetic unit independently calculates its own current information and the estimated current of the other system, eliminating the need for inter-unit communication while maintaining system independence and reducing overall control configuration complexity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Each arithmetic unit independently calculates the estimated current of the other system based on its own current instruction values and system parameters. This copying mechanism allows each unit to have complete information for decoupling control without requiring communication, thereby simplifying the overall control configuration while maintaining system independence.

Inventive Principle:

Principle #26Copying

4Productivity

If estimated current calculation is performed using own current instruction values, then communication load is reduced, but measurement precision may deteriorate

Engineering Contradiction:

Improvecommunication efficiencyVSAvoidcurrent information accuracy

Core Design Contradiction:

ProductivityVSMeasurement precision

Solution Approach 1:

The patent calculates the estimated current of the other system using its own current instruction values and system parameters (inductance, resistance, angular velocity). This copying approach creates a sufficiently accurate estimate for decoupling control purposes without requiring actual current information from the other system, thereby maintaining communication efficiency while achieving adequate measurement precision.

Inventive Principle:

Principle #26Copying

Data Source

PatentUS11088645B2Control device of multi-phase rotating machine

Publication Date: 2021.08.10 DENSO CORP

AI summary

Two systems of individually-provided arithmetic units in a control device of a multi-phase rotating machine perform control calculation for a control of electric current flowing from power converters to the multi-phase windings. The arithmetic units of the respective systems communicate information via inter-system communication at least in one direction, and perform current control calculation of the electric current flowing in the multi-phase windings of a subject system in a cycle shorter than a communication cycle of the inter-system communication, and calculate a decoupling control amount of the electric current flowing in the multi-phase windings of the subject system, for a decoupling control of a voltage generated in the multi-phase windings of the subject system by the electric current flowing in the multi-phase windings of an other system by using an estimated current that is calculated based on a current instruction value of the subject system or of the other system.