Switched Reluctance Motor Control Device Winding Pattern Switching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Switched reluctance motors face a challenge in improving maximum torque without degrading efficiency, particularly when employing the NSNSNS winding pattern, which can lead to inefficiencies under varying load states.
Innovation Solution
A control device for switched reluctance motors that dynamically switches between NNNSSS and NSNSNS winding patterns based on load states and applied voltage, using an inverter and electronic control unit to optimize torque and efficiency, while minimizing inverter heat and spark occurrence by controlling magnetic pole switching.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If the NSNSNS winding pattern is employed to improve maximum torque, then the maximum torque increases, but the efficiency degrades under certain load states
Solution Approach 1:
The patent applies dynamics by making the winding pattern switchable between NSNSNS and NNNSSS configurations based on real-time operating conditions. The control device dynamically selects the appropriate winding pattern according to torque demand and load state, transforming a static winding system into a dynamic one that adapts to varying operational requirements, thereby achieving both high torque capability and efficient operation across different load conditions
Solution Approach 2:
The patent employs parameter changes by altering the winding pattern configuration (from NSNSNS to NNNSSS or vice versa) as a controllable parameter. By changing the winding pattern parameter in response to torque and load state variations, the system optimizes performance - using NSNSNS for high torque requirements and NNNSSS for efficiency-critical operating conditions, thus resolving the contradiction between maximum torque and efficiency
2Productivity
If magnetic pole switching is performed to change winding patterns, then the winding pattern can be optimized for torque or efficiency, but sparks and heat generation occur in the inverter
Solution Approach 1:
The patent applies preliminary action by detecting the current state before magnetic pole switching and determining the optimal switching timing in advance. The control device predicts the best moment to switch winding patterns based on current trajectories and motor state, preparing the switching action beforehand to occur at the most favorable instant, thereby minimizing harmful effects like sparks and heat generation while achieving torque optimization
Solution Approach 2:
The patent employs feedback by continuously monitoring motor current, torque demand, and operating state, then using this feedback information to determine the optimal timing for magnetic pole switching. The control system adjusts switching timing based on real-time feedback from current sensors and motor performance, creating a closed-loop control that minimizes sparks and heat generation while maintaining optimal torque production
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 control device enhances maximum torque without degrading efficiency by adapting winding patterns to load states and voltage conditions, reducing inverter heat and spark occurrence, thus improving durability and efficiency.
Implementation Method 1
a switching circuit configured to switch a magnetic pole to provide a first winding pattern or a second winding pattern by changing a direction of current that flows in at least one phase of the three-phase coils
Implementation Method 2
The switched reluctance motor rotates the rotor by a magnetic attraction force generated between the salient poles of the stator and the rotor
Data Source
AI summary
A control device for a switched reluctance motor includes an inverter having a switching circuit that switches a magnetic pole to provide a first winding pattern or a second winding pattern. With respect to a boundary dividing a driving range of the switched reluctance motor into two ranges, the control device performs switching to the first winding pattern when the torque and the rotational speed are located in the first range on the low load side, performs switching to the second winding pattern when the torque and the rotational speed are located in the second range, allows switching of the magnetic pole in a case where a current of the phase whose magnetic pole is to be switched among the three-phase coils is 0, and prohibits switching of the magnetic pole in a case where the current of the phase whose magnetic pole is to be switched is not 0.