Synchronous Motor Startup Control with Pre-Start Rotor Phase Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing drive systems for synchronous motors face challenges in accurately assigning the phase in the low speed region during startup and shutdown, leading to potential failures in motor operation.
Innovation Solution
A drive system comprising an initial phase command generation unit, a rotor phase detection unit, and a drive control unit, which generates and adjusts phase command values to match the detected rotor phase before startup, ensuring accurate phase assignment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the synchronous motor is excited at startup to enable rotation, then the motor can start, but the rotor phase becomes difficult to identify
Solution Approach 1:
The system performs preliminary rotor phase detection using a position detector before the synchronous motor is excited and starts rotating. This preliminary action captures the rotor phase information at a standstill condition, avoiding the phase identification problem that occurs during rotation. The detected phase is then used to set the initial phase command value, ensuring accurate phase assignment from the start of motor operation.
2Reliability
If the phase assignment accuracy is insufficient in the low speed region, then the motor control is simpler, but the motor may not start properly
Solution Approach 1:
The system uses feedback from the position detector to continuously monitor and adjust the initial phase command value. The detected rotor phase is fed back to the initial phase command generation unit, which adjusts the phase command to match the actual rotor position. This closed-loop feedback mechanism ensures high phase assignment accuracy in the low speed region, enabling reliable motor startup.
Data Source
AI summary
A drive system of an embodiment includes an initial phase command generation unit, a rotor phase detection unit, and a drive control unit. The initial phase command generation unit generates a phase command value corresponding to an initial phase of a rotor before startup of a synchronous motor. The rotor phase detection unit detects a phase of the rotor and outputs the phase. The drive control unit controls the driving of the synchronous motor by using the phase command value. The initial phase command generation unit adjusts the phase command value to approach the phase of the rotor of a detection result by using the detection result of the phase of the rotor detected before the startup by the rotor phase detection unit.