Motor Voltage Saturation Control for Automatic Damping Adjustment

Solution Overview

Problem

Existing motor control techniques in the voltage saturation region require manual tuning of the voltage vector angle, which is time-consuming and ineffective when motor specifications or load conditions change, leading to inadequate damping effects.

Innovation Solution

A motor control device with a voltage command value generator and a control switching determination unit that adjusts the voltage command based on the torque command, velocity, and maximum output voltage, determining the control region and optimizing the voltage vector angle to improve damping effects.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If torque control is performed by fluctuating the voltage vector angle in synchronization with velocity fluctuation in the voltage saturation region, then damping effects are improved, but manual tuning is required which increases loss of time and reduces adaptability when motor specifications or load conditions change

Engineering Contradiction:

Improvedamping effectsVSAvoidmanual tuning time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The control device automatically determines the phase of voltage vector angle fluctuation based on motor operating conditions (velocity, torque command, current) without requiring manual tuning. The system self-adjusts the phase by calculating the phase difference between the fluctuating component of output current and voltage, and using this to determine the appropriate phase for voltage vector angle fluctuation, thereby achieving damping effects autonomously

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The system dynamically changes the phase parameter of voltage vector angle fluctuation based on operating conditions. By calculating phase difference from current and voltage measurements and adjusting the voltage vector angle phase accordingly, the system adapts to different motor specifications and load conditions without manual intervention

Inventive Principle:

Principle #35Parameter changes

2Reliability

If torque control is performed by fluctuating the voltage vector angle in synchronization with velocity fluctuation in the voltage saturation region, then damping effects are improved, but adaptability to different motor specifications and load conditions deteriorates due to requirement of retuning

Engineering Contradiction:

Improvedamping effectsVSAvoidadaptability to motor specifications and load conditions

Core Design Contradiction:

ReliabilityVSAdaptability or versatility

Solution Approach 1:

The system dynamically changes the phase parameter of voltage vector angle fluctuation based on operating conditions. By calculating phase difference from current and voltage measurements and adjusting the voltage vector angle phase accordingly, the system adapts to different motor specifications and load conditions without manual intervention

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The control device uses feedback from motor current and voltage measurements to automatically determine the optimal phase for voltage vector angle fluctuation. The phase difference between fluctuating components of current and voltage is calculated and used to adjust the voltage vector angle phase, creating a closed-loop system that adapts to changing conditions

Inventive Principle:

Principle #23Feedback

3Reliability

If the phase of voltage vector angle fluctuation is tuned under a certain condition, then damping effects can be obtained, but the voltage vector angle fluctuation for generating the optimum output torque is not achieved if the specification, load condition, and the like of inverter and motor change

Engineering Contradiction:

Improvedamping effects under certain conditionVSAvoidoptimum output torque under changing conditions

Core Design Contradiction:

ReliabilityVSAdaptability or versatility

Solution Approach 1:

The system dynamically changes the phase parameter of voltage vector angle fluctuation based on operating conditions. By calculating phase difference from current and voltage measurements and adjusting the voltage vector angle phase accordingly, the system adapts to different motor specifications and load conditions without manual intervention

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The system transitions from static manual tuning to dynamic automatic adjustment. The phase of voltage vector angle fluctuation is continuously updated based on real-time measurements of motor current and voltage, allowing the system to adapt to changing operating conditions and maintain optimal performance

Inventive Principle:

Principle #15Dynamics

Data Source

PatentUS12028002B2Motor control device

Publication Date: 2024.07.02 FUJITSU GENERAL LTD

AI summary

A motor control device capable of improving damping effects of a motor. In a motor control device, a control switching determination unit determines whether or not a control region of a motor is in a voltage saturation region. A voltage command value generator generates a voltage command value of the motor based on a velocity command value and a velocity of the motor. When the control switching determination unit determines that the control region of the motor is in the voltage saturation region, the voltage command value generator determines a voltage vector angle of an output voltage applied to the motor from a total torque command value and a limit value of the maximum voltage capable of being output to the motor, and generates a voltage command value based on the voltage vector angle.