EPE Association: EPE 2013 - DS3f: Sensorless Techniques, Reliable and Fault-Tolerant Drives

EPE 2013 - DS3f: Sensorless Techniques, Reliable and Fault-Tolerant Drives
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2013 ECCE Europe - Conference > EPE 2013 - Topic 12: High performance drives > EPE 2013 - DS3f: Sensorless Techniques, Reliable and Fault-Tolerant Drives

   [return to parent folder]

   A New Remedial strategy for Permanent Magnet Synchronous Motor Based on Artificial Neural Network
By Shady KHALIL, Haitham ABU-RUB, Mohamed SAAD, Essam ABOU-EL-ZAHAB, Atif IQBAL [View]
[Download]

Abstract: This paper proposes an effective approach to detect, isolate, and identify fault severity and post faultoperation of permanent magnet synchronous motors (PMSM) in the presence of stator winding turn fault.The paper proposes fault tolerant operation of PMSM under post condition with stator winding turn faultby using grounded neutral point through controllable impedance using artificial neural network (ANN).The fault detection and diagnosis is achieved by using a strategy based on the analysis of the ratio of third harmonic to fundamental waveform obtained from Fast Fourier Transform (FFT) of magnitudecomponents of the stator currents. The strategy helps to detect stator turn fault, isolate the faultycomponents, and estimate different insulation failure percentages and remedial operation of PMSM in thepresence of stator winding turn fault. The model of PMSM with stator winding turn fault is simulated atdifferent load conditions using a (2-D) Finite Element Analysis (FEA). Experimental results demonstratethe validity of the proposed technique.

   A sensorless stable V/f control method for a five phase PMSM
By Pau SALA-PEREZ, Daniel MONTESINOS-MIRACLE, Samuel GALCERAN-ARELLANO [View]
[Download]

Abstract: This paper presents a sensorless and stable control method for a five-phase permanent magnet synchronous motor (PMSM). At first, a model of a five-phase PMSM is presented. After that a stability study has been performed by the analysis of the eigenvalues of the state transition matrix of the linearized PMSM model about an operating point. The results show that the machine speed response is unstable for input frequencies below the machine rated frequency. Finally, an open-loop V/f stabilization algorithm which ensures the stability of the system over a wide range of speed is presented.

   Analysis of Harmonics on a MRAS system used for Sensorless Control of a DFIG
By Kris SCICLUNA, C.S. SPITERI, Maurice APAP [View]
[Download]

Abstract: This paper presents a Model Reference Adaptive System (MRAS) applied to the sensorless control of a DFIG system. The performance of the MRAS is enhanced by introducing a voltage model bandpass filter approximation to compensate for drift. Control is performed by a rotor-side matrix converter and is limited to the most common speed range in wind systems. Moreover a detailed analysis of the effects of current harmonics on the MRAS is carried out and a means of mitigation is proposed.

   Encoderless Model Predictive Control of Back-to-Back Converter Direct-Drive Permanent-Magnet Synchronous Generator Wind Turbine Systems
By Christoph HACKL, Fengxiang WANG, Zhenbin ZHANG, Christoph HACKL, Ralph KENNEL, Zhe CHEN [View]
[Download]

Abstract: This paper presents encoderless model predictive control scheme with time-varying sliding mode ob-server for a complete wind turbine system. The wind turbine system consists of a back-to-back converter (AC/DC/AC) and a direct-drive permanent-magnet synchronous generator (PMSG). We give a complete model of the system and present encoderless fixed-frequency model predictive direct torque control of the generator and finite-set model predictive direct power control of active and reactive power on the grid side. The sliding mode observer utilizes a time-varying switching gain and a time-varying cut-off frequency to estimate rotor position and rotor speed without chattering. The proposed strategy is illustrated by simulations as a first proof of concept. The simulation results show that the proposed strategy achieves fast torque control dynamics and highly decoupled control of active and reactive power.

   Influence of Magnetic Saturation on Sensorless-Controlled Interior Permanent Magnet Synchronous Motors
By Thomas ORLIK, Jan KLOCK, Walter SCHUMACHER [View]
[Download]

Abstract: This contribution investigates the influence of magnetic saturation on the sensorless control of IPM synchronous motors. An extended analytical motor model is introduced that covers magnetic anisotropiesand describes the fundamental wave as well as the harmonic characteristics. Simulation results are compared to actual measurements on a servo drive.

   Influence of rotor saturation on the differential inductances of PM-synchronous machines with concentrated winding
By Johannes GRAUS, Sven LUTHARDT, Ingo HAHN [View]
[Download]

Abstract: For sensorless position detection of permanent magnet synchronous machines at very low speed and standstill, signal injection methods are commonly used. As a prerequisite these so called saliency-tracking methods require a differential magnetic anisotropy of the machine, which is both position and load dependent and thus varying during operation. So the performance of sensorless operation strongly depends on the machine design. To investigate the influence of the rotor saturation a machine model based on a magnetic equivalent circuit (MEC) is presented in this document. This model is then used to analyze the differential inductances of a machine with concentrated windings. The results are then explained by an analysis of the main flux paths of the machine in several operating points.

   PMSM Position Sensorless Control in the Inverter Overmodulation range
By Ryunosuke AKIMATSU, Shinji DOKI [View]
[Download]

Abstract: In this paper, Permanent Magnet Synchronous Motor(PMSM) position sensorless control system in the inverter overmodulation range has been proposed. Operating PMSM in the inverter overmodulation range achieves fast torque response and widens high-speed drive region of PMSM. In the range, how-ever, because of the effect from harmonic currents, a closed loop current control system become unstable, further more because of harmonic voltage output from the inverter makes position estimation error and it may destabilize sensorless control system. First of all describes mechanism of destabilization of sensor-less control system in the overmodulation range. Second of all propose PMSM sensorless control system with the inverter model and the harmonic current model which stabilizes control system. Last of all the experimental results show that the proposed sensorless control system achieves widening high-speed drive region.

   Sensorless Control of a Novel IPMSM Based on High-Frequency Injection
By Xiaocan WANG, Ralph KENNEL, Wei XIE, Dieter GERLING [View]
[Download]

Abstract: Due to the challenge for sensorless control of concentrated windings (CW) interior permanent magnet synchronous machines (IPMSMs) , this paper presents the analysis of a novel stator IPMSM for sensorless control based on high-frequency rotating voltage signal injection method. The topology of the machine is introduced and the new IPMSM has the advantage of less space harmonics. The sensorless control scheme is developed, and the cross saturation is taken into account to improve the accuracy of position estimation. To support this, the high-frequency inductances of the machine are analyzed by finite-element analysis (FEA) method. Both of the steady and dynamic state experimental results verify the effectiveness of the drive system.

   Sensorless control of PMSM fed through the sinusoidal filter
By Konrad URBANSKI [View]
[Download]

Abstract: The paper presents results of a research on the sensorless drive with PMSM supplied through the sinusoidal filter. The back electromotive force based observer is used to the shaft position estimation. Used in the study, the observer's correction function, contains multi integrators in the path, which improves the position estimation. Otherwise than in a typical implementation of the position observer, the presence of the filter was not taken into account in observer structure, however, it was taken into account in the observer parameters. This type of control allows the use of conventional control system and there is no need to take account the filter in the control circuit. Presented concept has been proven in laboratory.

   Sensorless technique and drive setup for high pole number Brushless DC motors operated with single stage inverters
By David GRISCTI, Joseph CILIA, Maurice APAP [View]
[Download]

Abstract: This paper describes the electronics and sensorless control algorithm implemented in an experimental setup to operate a 3 phase, high pole number, brushless DC motor through a single stage inverter. The use of a high PWM switching frequency imposed on the motor phases for torque and speed control generates noise on the sensing and drive circuitry. Thus the first part of this paper focuses on designing noise immune feedback and control circuitry containing the required galvanic isolation. The second part of this paper focuses on the development of a sensorless algorithm based on back-emf voltage sensing to commutate between phases. The outcome of this algorithm is useful when the motor is operated from medium to high speed. This sensorless algorithm uses synchronous sampling of direct terminal voltages measurement. Then through an innovative digital estimation technique, the zero crossing of the back-emf of the concurrently unenergized phase is calculated. This technique avoids the use of passive filters on terminal voltage sensing thus eliminating undesired phase shifts that cause erratic phase commutation. Validity of this technique during steady state and transient operation is shown through simulation and practical results obtained with the experimental setup. Moreover the limitations encountered on employing the designed algorithm on the experimental setup are also discussed.

   Sensorless torque control of PMSMs for railway traction applications
By Maitane AGUIRRE, Javier POZA, Leire ALDASORO, Txomin NIEVA [View]
[Download]

Abstract: This work presents a sensorless torque control of permanent magnet synchronous machines (PMSM) inrailway traction applications based on the flux estimation. In order to improve the algorithm performancein a wide speed range, some compensation loops are included. Special techniques for standstill and flyingstart are also proposed. The sensorless control strategy is validated in a railway simulation platform fora 120kW surface mounted PMSM tramway motor prototype.

   Use of an Artificial Neural Network for Current Derivative Estimation
By David HIND, Mark SUMNER, Christopher GERADA [View]
[Download]

Abstract: The Fundamental PWM technique for saliency tracking based sensorless (encoderless) motor control uses current derivative measurements to calculate the rotor position. However parasitic impedances in the drive, motor and cabling cause high frequency oscillations in the current, when the inverter�s IGBTs switch. This prevents the immediate measurement of the current derivative when a new voltage is imposed on the motor and has led to an enforced minimum PWM vector time restriction that allows the oscillations in the current response to decay sufficiently before current derivative measurements are made. In this work a new method is proposed to reduce this minimum PWM vector time restriction by estimating the current derivative in the presence of such oscillations using a neural network. Training of the neural network is performed off-line with the neural network configuration (weights and biases) being stored on removable storage media. This can reduce the training burden by allowing network configurations to be saved and recalled, potentially offering a �plug and play� solution for previously encountered drive setups. An additional benefit of the proposed solution is that the current derivative is estimated from data captured using standard industrial current sensors instead of dedicated current derivative sensors. The proposed method and its implementation are discussed and on-line experimental results are presented which validate the feasibility and performance of the proposed technique.

EPE 2013 - DS3f: Sensorless Techniques, Reliable and Fault-Tolerant Drives
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2013 ECCE Europe - Conference > EPE 2013 - Topic 12: High performance drives > EPE 2013 - DS3f: Sensorless Techniques, Reliable and Fault-Tolerant Drives
	[return to parent folder]

	A New Remedial strategy for Permanent Magnet Synchronous Motor Based on Artificial Neural Network By Shady KHALIL, Haitham ABU-RUB, Mohamed SAAD, Essam ABOU-EL-ZAHAB, Atif IQBAL	[View] [Download]
Abstract: This paper proposes an effective approach to detect, isolate, and identify fault severity and post faultoperation of permanent magnet synchronous motors (PMSM) in the presence of stator winding turn fault.The paper proposes fault tolerant operation of PMSM under post condition with stator winding turn faultby using grounded neutral point through controllable impedance using artificial neural network (ANN).The fault detection and diagnosis is achieved by using a strategy based on the analysis of the ratio of third harmonic to fundamental waveform obtained from Fast Fourier Transform (FFT) of magnitudecomponents of the stator currents. The strategy helps to detect stator turn fault, isolate the faultycomponents, and estimate different insulation failure percentages and remedial operation of PMSM in thepresence of stator winding turn fault. The model of PMSM with stator winding turn fault is simulated atdifferent load conditions using a (2-D) Finite Element Analysis (FEA). Experimental results demonstratethe validity of the proposed technique.

	A sensorless stable V/f control method for a five phase PMSM By Pau SALA-PEREZ, Daniel MONTESINOS-MIRACLE, Samuel GALCERAN-ARELLANO	[View] [Download]
Abstract: This paper presents a sensorless and stable control method for a five-phase permanent magnet synchronous motor (PMSM). At first, a model of a five-phase PMSM is presented. After that a stability study has been performed by the analysis of the eigenvalues of the state transition matrix of the linearized PMSM model about an operating point. The results show that the machine speed response is unstable for input frequencies below the machine rated frequency. Finally, an open-loop V/f stabilization algorithm which ensures the stability of the system over a wide range of speed is presented.

	Analysis of Harmonics on a MRAS system used for Sensorless Control of a DFIG By Kris SCICLUNA, C.S. SPITERI, Maurice APAP	[View] [Download]
Abstract: This paper presents a Model Reference Adaptive System (MRAS) applied to the sensorless control of a DFIG system. The performance of the MRAS is enhanced by introducing a voltage model bandpass filter approximation to compensate for drift. Control is performed by a rotor-side matrix converter and is limited to the most common speed range in wind systems. Moreover a detailed analysis of the effects of current harmonics on the MRAS is carried out and a means of mitigation is proposed.

	Encoderless Model Predictive Control of Back-to-Back Converter Direct-Drive Permanent-Magnet Synchronous Generator Wind Turbine Systems By Christoph HACKL, Fengxiang WANG, Zhenbin ZHANG, Christoph HACKL, Ralph KENNEL, Zhe CHEN	[View] [Download]
Abstract: This paper presents encoderless model predictive control scheme with time-varying sliding mode ob-server for a complete wind turbine system. The wind turbine system consists of a back-to-back converter (AC/DC/AC) and a direct-drive permanent-magnet synchronous generator (PMSG). We give a complete model of the system and present encoderless fixed-frequency model predictive direct torque control of the generator and finite-set model predictive direct power control of active and reactive power on the grid side. The sliding mode observer utilizes a time-varying switching gain and a time-varying cut-off frequency to estimate rotor position and rotor speed without chattering. The proposed strategy is illustrated by simulations as a first proof of concept. The simulation results show that the proposed strategy achieves fast torque control dynamics and highly decoupled control of active and reactive power.

	Influence of Magnetic Saturation on Sensorless-Controlled Interior Permanent Magnet Synchronous Motors By Thomas ORLIK, Jan KLOCK, Walter SCHUMACHER	[View] [Download]
Abstract: This contribution investigates the influence of magnetic saturation on the sensorless control of IPM synchronous motors. An extended analytical motor model is introduced that covers magnetic anisotropiesand describes the fundamental wave as well as the harmonic characteristics. Simulation results are compared to actual measurements on a servo drive.

	Influence of rotor saturation on the differential inductances of PM-synchronous machines with concentrated winding By Johannes GRAUS, Sven LUTHARDT, Ingo HAHN	[View] [Download]
Abstract: For sensorless position detection of permanent magnet synchronous machines at very low speed and standstill, signal injection methods are commonly used. As a prerequisite these so called saliency-tracking methods require a differential magnetic anisotropy of the machine, which is both position and load dependent and thus varying during operation. So the performance of sensorless operation strongly depends on the machine design. To investigate the influence of the rotor saturation a machine model based on a magnetic equivalent circuit (MEC) is presented in this document. This model is then used to analyze the differential inductances of a machine with concentrated windings. The results are then explained by an analysis of the main flux paths of the machine in several operating points.

	PMSM Position Sensorless Control in the Inverter Overmodulation range By Ryunosuke AKIMATSU, Shinji DOKI	[View] [Download]
Abstract: In this paper, Permanent Magnet Synchronous Motor(PMSM) position sensorless control system in the inverter overmodulation range has been proposed. Operating PMSM in the inverter overmodulation range achieves fast torque response and widens high-speed drive region of PMSM. In the range, how-ever, because of the effect from harmonic currents, a closed loop current control system become unstable, further more because of harmonic voltage output from the inverter makes position estimation error and it may destabilize sensorless control system. First of all describes mechanism of destabilization of sensor-less control system in the overmodulation range. Second of all propose PMSM sensorless control system with the inverter model and the harmonic current model which stabilizes control system. Last of all the experimental results show that the proposed sensorless control system achieves widening high-speed drive region.

	Sensorless Control of a Novel IPMSM Based on High-Frequency Injection By Xiaocan WANG, Ralph KENNEL, Wei XIE, Dieter GERLING	[View] [Download]
Abstract: Due to the challenge for sensorless control of concentrated windings (CW) interior permanent magnet synchronous machines (IPMSMs) , this paper presents the analysis of a novel stator IPMSM for sensorless control based on high-frequency rotating voltage signal injection method. The topology of the machine is introduced and the new IPMSM has the advantage of less space harmonics. The sensorless control scheme is developed, and the cross saturation is taken into account to improve the accuracy of position estimation. To support this, the high-frequency inductances of the machine are analyzed by finite-element analysis (FEA) method. Both of the steady and dynamic state experimental results verify the effectiveness of the drive system.

	Sensorless control of PMSM fed through the sinusoidal filter By Konrad URBANSKI	[View] [Download]
Abstract: The paper presents results of a research on the sensorless drive with PMSM supplied through the sinusoidal filter. The back electromotive force based observer is used to the shaft position estimation. Used in the study, the observer's correction function, contains multi integrators in the path, which improves the position estimation. Otherwise than in a typical implementation of the position observer, the presence of the filter was not taken into account in observer structure, however, it was taken into account in the observer parameters. This type of control allows the use of conventional control system and there is no need to take account the filter in the control circuit. Presented concept has been proven in laboratory.

	Sensorless technique and drive setup for high pole number Brushless DC motors operated with single stage inverters By David GRISCTI, Joseph CILIA, Maurice APAP	[View] [Download]
Abstract: This paper describes the electronics and sensorless control algorithm implemented in an experimental setup to operate a 3 phase, high pole number, brushless DC motor through a single stage inverter. The use of a high PWM switching frequency imposed on the motor phases for torque and speed control generates noise on the sensing and drive circuitry. Thus the first part of this paper focuses on designing noise immune feedback and control circuitry containing the required galvanic isolation. The second part of this paper focuses on the development of a sensorless algorithm based on back-emf voltage sensing to commutate between phases. The outcome of this algorithm is useful when the motor is operated from medium to high speed. This sensorless algorithm uses synchronous sampling of direct terminal voltages measurement. Then through an innovative digital estimation technique, the zero crossing of the back-emf of the concurrently unenergized phase is calculated. This technique avoids the use of passive filters on terminal voltage sensing thus eliminating undesired phase shifts that cause erratic phase commutation. Validity of this technique during steady state and transient operation is shown through simulation and practical results obtained with the experimental setup. Moreover the limitations encountered on employing the designed algorithm on the experimental setup are also discussed.

	Sensorless torque control of PMSMs for railway traction applications By Maitane AGUIRRE, Javier POZA, Leire ALDASORO, Txomin NIEVA	[View] [Download]
Abstract: This work presents a sensorless torque control of permanent magnet synchronous machines (PMSM) inrailway traction applications based on the flux estimation. In order to improve the algorithm performancein a wide speed range, some compensation loops are included. Special techniques for standstill and flyingstart are also proposed. The sensorless control strategy is validated in a railway simulation platform fora 120kW surface mounted PMSM tramway motor prototype.

	Use of an Artificial Neural Network for Current Derivative Estimation By David HIND, Mark SUMNER, Christopher GERADA	[View] [Download]
Abstract: The Fundamental PWM technique for saliency tracking based sensorless (encoderless) motor control uses current derivative measurements to calculate the rotor position. However parasitic impedances in the drive, motor and cabling cause high frequency oscillations in the current, when the inverter�s IGBTs switch. This prevents the immediate measurement of the current derivative when a new voltage is imposed on the motor and has led to an enforced minimum PWM vector time restriction that allows the oscillations in the current response to decay sufficiently before current derivative measurements are made. In this work a new method is proposed to reduce this minimum PWM vector time restriction by estimating the current derivative in the presence of such oscillations using a neural network. Training of the neural network is performed off-line with the neural network configuration (weights and biases) being stored on removable storage media. This can reduce the training burden by allowing network configurations to be saved and recalled, potentially offering a �plug and play� solution for previously encountered drive setups. An additional benefit of the proposed solution is that the current derivative is estimated from data captured using standard industrial current sensors instead of dedicated current derivative sensors. The proposed method and its implementation are discussed and on-line experimental results are presented which validate the feasibility and performance of the proposed technique.