Multi-Winding PM Machine Fault Control for Torque Oscillation Damping
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for controlling multi-winding set permanent magnet electrical machines during faults, such as short-circuits, are inadequate in damping torque oscillations and reducing component damage, leading to potential generator shutdown and increased maintenance costs.
Innovation Solution
A method that determines the torque generated by all winding sets and controls the currents of the functional winding sets to reduce demagnetization currents, torque oscillations, and fault torques, using Id and Iq control, and feedback signals like torque values to safely shut down the generator and minimize component damage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional fault control methods are used in multi-winding set permanent magnet electrical machines, then the generator can be stopped to allow fixing or repairing damages, but torque oscillations and demagnetization currents are not adequately damped, leading to component damage
Solution Approach 1:
The patent converts the harmful torque oscillation caused by the faulty winding set into a beneficial control signal. By detecting the torque oscillation and using it as feedback, the system generates a counteracting torque from the healthy winding sets that precisely opposes the oscillation, thereby damping it. This transforms the harmful effect into a useful control mechanism for protecting the generator.
Solution Approach 2:
The patent implements a feedback control mechanism where the torque oscillation detected from the faulty winding set is continuously monitored and fed back to the control system. The controller uses this feedback information to dynamically adjust the current references of the healthy winding sets, generating a counteracting torque that opposes the oscillation in real-time, thereby damping the torque oscillation and protecting the generator components.
2Object-affected harmful factors
If the generator is stopped immediately upon fault detection to prevent component damage, then component safety is improved, but the operational time and energy loss increase
Solution Approach 1:
The patent applies preliminary action by implementing a control mechanism that activates immediately upon fault detection to dampen torque oscillations and protect components. Instead of immediately shutting down, the system preliminarily engages the healthy winding sets to counteract the harmful effects, extending the operational time safely until maintenance can be performed.
Solution Approach 2:
The patent provides beforehand cushioning by using the healthy winding sets to generate a counteracting torque that cushions against the harmful torque oscillation from the faulty winding set. This protective action is prepared and applied in advance of potential component damage, allowing the generator to continue operating safely rather than requiring immediate shutdown.
3Object-affected harmful factors
If additional switching devices are used to force three-phase short-circuit to minimize oscillations, then torque oscillation damping is improved, but device complexity and cost increase
Solution Approach 1:
The patent applies self-service by utilizing the existing healthy winding sets to dampen the torque oscillation caused by the faulty winding set. The system serves itself by using its own functional components (healthy winding sets) to counteract the harmful effects, eliminating the need for additional external switching devices or complex protection circuitry.
Solution Approach 2:
The patent demonstrates universality by making the healthy winding sets perform multiple functions: their normal power generation function and an additional protective function of damping torque oscillations. This multi-functionality allows the existing components to handle both operational and protective roles without requiring dedicated additional devices.
4Object-affected harmful factors
If the current control of healthy winding sets is adjusted to counteract torque oscillation, then component protection is improved, but control complexity increases
Solution Approach 1:
The patent uses feedback control by continuously monitoring the torque oscillation from the faulty winding set and using this information to dynamically adjust the current references of the healthy winding sets. The controller calculates the oscillating component and generates appropriate counteracting currents in real-time, protecting against demagnetization while maintaining manageable control complexity through systematic feedback processing.
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 approach effectively damps torque oscillations, reduces short-circuit currents, and prevents demagnetization, allowing for faster and safer shutdown of the generator, thereby reducing the risk of component damage and operational costs.
Implementation Method 1
A method for controlling a multi winding set permanent magnet electrical machine in case of a fault in a first group of the winding sets leaving a second group of the winding sets functional, the method comprising: determining a value of a torque generated by all winding sets; and controlling values of currents of the second group of winding sets based on the value of a torque
Data Source
Figure 1
Figure 2
Figure 3
AI summary
It is described a method and arrangement (141) for controlling a multi winding set permanent magnet electrical machine (111) in case of a fault in a first group of the winding sets (113) leaving a second group of the winding sets (117) functional, the method comprising: determining a value of a torque (154) generated by all winding sets; and controlling values of currents (155, 156) of the second group of winding sets (117) based on the value (154) of a torque, in order to reduce a damaging torque and/or a torque oscillation occurring and/or to break the machine.