Motor Control Apparatus Mode Switching Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Motor control systems face instability when switching between control modes, particularly due to differences in torque applied to the rotor during transitions from constant-current control to vector control, leading to fluctuations in rotation speed and potential motor control instability.
Innovation Solution
A motor control apparatus that includes a detector for driving current, a phase determiner for rotor rotation phase, and a controller with two modes: one for setting a target phase deviation and another for maintaining a previously determined current magnitude, where the target value in the first mode is set based on the torque current component during the second mode, ensuring a smooth transition and appropriate torque application.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If motor control is switched from constant-current control to vector control, then control precision and efficiency are improved, but rotation speed fluctuates and control stability deteriorates
Solution Approach 1:
The patent applies preliminary action by setting the initial torque current component in vector control based on the current value from constant-current control before switching. This pre-preparation ensures that the torque applied to the rotor remains continuous, preventing rotation speed fluctuations and maintaining control stability during the transition from constant-current control to vector control.
2Reliability
If torque current component is increased to prevent step-out state, then reliability is improved, but power consumption increases
Solution Approach 1:
The patent applies dynamics by making the torque current component adjustable based on actual load conditions rather than using a fixed high value. The control system dynamically optimizes the torque current component to be the minimum necessary to prevent step-out state, thereby maintaining reliability while reducing unnecessary power consumption.
Solution Approach 2:
The patent uses feedback by continuously monitoring the motor's operation state and adjusting the torque current component accordingly. The control system feeds back information about the actual load and motor performance to optimize the torque current component, ensuring reliability is maintained only when necessary and power consumption is reduced when the load is light.
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
This solution stabilizes motor control by ensuring accurate torque application during mode switches, reducing rotation speed fluctuations and maintaining motor stability, thus preventing uncontrollable states and excess power consumption.
Implementation Method 1
a detector configured to detect a driving current flowing through a winding of the motor
Implementation Method 2
a configuration for determining the rotation phase of the rotor based on an induced voltage generated in the winding in each phase of the motor when the rotor rotates
Data Source
AI summary
An apparatus, to control a motor from an instructed phase indicating a motor rotor target phase, includes a detector, a phase determiner, a converter, and a controller. The detector detects a motor winding driving current. The phase determiner determines a rotor rotation phase from the detected driving current. The converter converts a detected current value in a stationary coordinate system into a current value in a rotational coordinate system from the determined rotation phase. The controller includes a first mode for controlling the driving current to cause a determined phase deviation between the instructed and rotation phases to decreased, and a second mode for controlling the driving current from a current having a previously determined magnitude. On switching the mode from the second to the first mode, the first mode target value is set from a driving current value corresponding to a current component represented by the rotational coordinate system.