EPE Association: EPE-PEMC 2008 - Topic: Measurements, Sensors and Observing Techniques

EPE-PEMC 2008 - Topic: Measurements, Sensors and Observing Techniques
You are here: EPE Documents > 04 - EPE-PEMC Conference Proceedings > EPE-PEMC 2008 - Conference > EPE-PEMC 2008 - Topic: Measurements, Sensors and Observing Techniques

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   A Development System for Testing Integrated Circuits Used for Power and Energy Measurements
By VladimirĆuk [View]
[Download]

Abstract: A development system for testing integrated circuits used for power and energy measurements is presented in the paper. System is based on a DSP board, a data acquisition (DAQ) board and a computer with a real time mathematical model. The aim of the paper is to provide observing of measurement accuracy in the laboratory and to simulate different conditions with the "phantom load" technique: nonlinearity, high-order harmonics, phase unbalance, voltage sag, etc.

   A New, Ultra-Low-Cost Power Quality and Energy Measurement Technology
By Alex McEachern [View]
[Download]

Abstract: IEC 61000-4-30 is an excellent standard that ensures that all compliant power quality instruments, regardless of manufacturer, will produce the same results when connected to the same signal. However, instruments that comply with the Class A requirements of this standard have, until now, been too expensive for common use. Now a new set of technologies developed by an American company, in cooperation with a Japanese company, demonstrate that it is possible to manufacture three-phase power quality instruments that are fully compliant with the Class A requirements of IEC 61000-4-30 at ultra-low-cost to allow putting this monitoring devices even at entry levels of individual loads. The development uses technologies from several fields that have not previously been related to power quality, including digital cameras, power-over-ethernet, mobile phones, and submarine sonar systems. These new technologies have been packaged in a demonstration instrument, and may be licensed to instrument manufacturers as well. This allows gathering power quality and energy consumption information throughout manufacturing facilities or commercial buildings.

   Application of Speed and Load Torque Observes in High Speed Train
By Jaroslaw Guzinski [View]
[Download]

Abstract: This paper presents a solution for observer based diagnostic system in high speed train with induction motor. The concept of the diagnostic system is dedicated to the mechanical part of the drive. The system is monitoring both motor speed sensor and torque transmission system. In case of speed sensor fault the control system could be switched into sensorless mode. Monitoring of torque Transmission system allows to limit the motor torque in case of serious problem and gives an information to maintenance center for testing the suspected gear. The proposed system was verified by simulation and in test bench for 1.2 MW rail induction motor.

   Asynchronous Machine Stator Resistance Estimation Using Integrated PWM Modulator and Sampler Unit as FPGA Application
By Dag Samuelsen [View]
[Download]

Abstract: The paper demonstrates how a simple, low-cost and effective stator resistance estimation scheme for FPGA can be employed, utilizing the large degree of freedom a FPGA impose with regard to system design, while at the same time conform to the constraints the same technology infer. In a computing system, a FPGA removes the limitations of the Von Neuman-architecture. Although the (Super) Harward architecture, used by most DSP processors, relieve this limitations, this is not anywhere near the power of the parallel computing capability of FPGA. A FPGA is at the same time somewhat limited with regard to complexity of mathematical operations. Although this limitations has been removed with the introduction of FPGA with embedded CPU, there are still reasons for keeping the design simple, when overall cost should kept low. The estimator has been tested on an asynchronous machine, with satisfying results.

   Design of an FPGA-Based Real-Time Simulator for Electrical System
By I. Bahri [View]
[Download]

Abstract: This paper deals with a Real-Time Simulation (RTS) able to accurately reproduce an electrical system in real-time. The RTS proposed architecture is written in VHDL and implemented in a Field Programmable Gate Array (FPGA) device. Multi-sampling approach is adopted allowing a real-time functioning with different time-steps and different operating conditions with minimized lost of accuracy. The proposed concept is illustrated by the RTS of each of a three-phase RLE load performed with a very short time step of 2.5 μs, an inverter, the measurement system and the hysteresis current controllers. Comparison with experimental results shows the high performances of this RTS.

   Development of Monitoring System for Series HEV Bus with Touch Panel
By Tae-Won Chun [View]
[Download]

Abstract: In this paper, the monitoring strategies for a series hybrid electric vehicle (SHEV) bus are suggested for the optimal operation of powertrain and detection of abnormal conditions during the initial development of hybrid technologies. The monitoring system receives the messages from four control modules in the SHEV bus through a CAN, and then displays the data in the messages on a touch panel. In addition, all gauges and the on/off switching state of a set of telltale lamps are indicated. The monitoring system is implemented by both the 32-bit DSP and touch panel, and it is installed and tested on the real SHEV bus.

   Injection of a Carrier with Higher than the PWM Frequency for Sensorless Position Detection in PM Synchronous Motors
By Roberto Leidhold [View]
[Download]

Abstract: The injection of an alternating carrier allows detecting the rotor position in PM synchronous motors. It is usually injected through the PWM, being therefore limited to about 1/5 of the switching frequency. By increasing the carrier frequency beyond the switching one, the bandwidth of the position observer can be significantly increased and audible noise can be reduced, among other advantages. A method is proposed to inject a carrier with a higher than the PWM frequency by coupling an external source through a transformer and a filter. An analysis of the advantages and difficulties, as well as experimental results, are presented.

   Nonlinear Dynamical Feedback for Motion Control of Magnetic Levitation System
By Jerzy Baranowski and Pawel Piatek [View]
[Download]

Abstract: For fast, nonlinear and unstable dynamical systems, such as magnetic levitation, high quality of control is essential. Such control can be generated by different feedback structures, most of which require measurements of velocities or derivatives of the system output. In case of magnetic levitation the velocity of levitating object (a ferromagnetic sphere) is not measured. That is the reason for application of state observers which along with different controllers will create a nonlinear dynamical feedback structure. In this paper we will consider two such structures - PID controller with a nonlinear feed-forward and a cascade linearising feedback using two nonlinear state observers: High-Gain observer (HGO) and an observer with reduced, linear error dynamics (abbreviated as RO). Operation of these control algorithms will be compared with a classical PID structure, derivative part of which will be realised either as a finite difference or with an observer.

   Parallel Fixed Point FPGA Implementation of Sensorless Induction Motor Torque Control
By Jacek D. Lis and Czeslaw T. Kowalski [View]
[Download]

Abstract: The paper deals with the FPGA implementation of an sensorless motor control application. The parallel processing approach is described. Few issues concerning the implementation are discussed. The method for the qualitative analysis of the considered state observer's sensitivity to the variations of the induction motor equivalent circuit parameters is presented. The experimental tests of the FPGA based implementation of the whole control structure of the sensorless DTC drive system are demonstrated.

   Position Estimator including Saturation and Iron Losses for Encoder Fault Detection of Doubly-Fed Induction Machine
By Kai Rothenhagen [View]
[Download]

Abstract: Fault tolerance is gaining interest to increase reliability and availability, for example for distributed energy systems. Doubly fed induction generators need rotor position information for high performance control. As part of a multi-sensor fault tolerant generator system, fault tolerance of the position sensor is presented, using a position estimator. A known position estimator is improved and thoroughly described, including effects of machine saturation and iron losses. The fault detection and isolation is described and the reconfiguration from encoder to sensorless operation is shown. Measurements are provided and show good and fast results. Steady state properties of encoder and sensorless operation are compared.

   Rotor Time Constant Adaptation Using Radial Basis Function Network
By Pavel Brandstetter [View]
[Download]

Abstract: Our intention here was to highlight a replacement of adaptation algorithm in MRAS by the help of alternative artificial neural network (ANN) which has received great attention in recent years. The main objective was to find and design some alternative neural network within the electric drive control. After a short discussion of hardware components, an overview of Radial Basis Function (RBF) neural networks will be given. Digital signal processors TMS320F2812 are used for these electric drives control applications. The hardware accessories used within the electric control drive included: interface board for the signal processor kit-developed in our department, and an 8bit data-transfer microprocessor for data acquisition. The interface of the DSP is a general-purpose control system for power converters in the electric drives. The next section briefly outlines the estimation of the rotor time constant, which is necessary for the so-called current model. The current model is used in the vector control of the induction motor and is utilized to determine the quantities for the transformation from the stationary reference frame into the reference frame, which is oriented on the rotor flux space vector. The estimation of the rotor time constant for the adaptive model of MRAS is created with the support of a PI-controller which is then replaced with the Radial Basis Function network. The final section presents simulations results, which have been performed in the Matlab-Simulink software.

   Speed and Position Estimation of SRM
By Konrad Urbanski [View]
[Download]

Abstract: The paper deals with the problem of speed and position estimation in SRM drive equipped with hysteresis band current controller. Instead of measured current the observer utilize reference current. The voltage is calculated from switching ontime. A speed observer structure which uses estimated back EMF and current of each phase is presented. The shaft position is integrated from estimated speed signal.

   State and Parameter Estimation in a Hydraulic System - Moving Horizon Approach
By Jerzy Baranowski [View]
[Download]

Abstract: In most control systems the best quality of control can be achieved if an exact model of a plant is known and if disturbances-free and continuous (instead of discrete) measurements of all its state space variables are available. Since it is seldom the case in real-life installations, state observers, adapting (parameters identification) algorithms, anti-noise filters and continuous signal estimators must be often employed. The paper describes an application of the moving horizon estimation (MHE) and continuous state estimation from discrete output measurements (CSEDOM) based method to a laboratory hydraulic three-tank system. The resulting algorithm encompasses all the four above-mentioned mechanisms (state observation, parameters identification, disturbances filtration and continuous state estimation) and can be used for nonlinear systems as well, which is the case in the presented article. The paper provides a detailed explanation of how the MHE and CSEDOMmethods were adapted to be applicable to the three-tank system. Results of computer simulations and practical laboratory experiments are also included.

   Study About the Possibility of Electrodes Motion Control in the EAF Based on Adaptive Impedance Control
By Manuela Panoiu [View]
[Download]

Abstract: The paper presents a study about the possibility of adaptive process control in three phased electric arc furnace. The method is based on the electrodes motion control. The control principle is depending on impedance of the electric arc. The method proposed use a data acquisition board whose input signals are taken from electric arc. These signals allow the calculation of electric arc impedance. Using a numeric computer, it can be commands the control of electrodes position independently on each one of three phases. We propose to use a static frequency converter on each phase to control the electrodes motion.

   Technologies of Current Sensors Suitable for Hot High Density Power Electronics
By Filip Grecki [View]
[Download]

Abstract: The paper describes the review of technologies of current sensors dedicated for high temperature power electronics. Two solutions are taken into consideration as the drive system and DC/DC converter implemented in Hybrid and Electric cars requires different parameters of current measurement system - the current range and switching frequency are various in both cases. Demands for current sensors, ideas of basic system are described.

   Transducerless Speed Control with Initial Position Detection for Low Cost PMSM Drives
By Roman Filka [View]
[Download]

Abstract: This paper presents an approach for vector control of IPM synchronous motor without position transducer, applicable for low cost PMSM drives with unpredictable load and inertia. To achieve correct drive operation from zero speed, two different techniques are combined with crossover function, based on the speed reference. The rotor initial position is determined prior the control action, for the drive to deliver the full start up torque. Since back-EMF observer estimations are insufficiently accurate under limited angular speed, the zero speed startup and low speed acceleration is used. The back-EMF observer detects the generated motor voltages induced by the permanent magnets. An angle tracking observer uses the back-EMF signals to calculate the position and speed of the rotor. The experimental results based on dsp MC56F8025 show sufficient performance for washing machine, pumps, and fan applications.

   Wide Range Low Noise Current Sensor
By F. Richter and C. Sourkounis [View]
[Download]

Abstract: Compared to conventional current sensors, the proposed topology is advantageous because of its high resolution throughout its full measurement range, thus reducing offsets to a minimum. This aim is reached through active offset compensation using an analog/digital chopper/de-chopper. A further advantage is the excellent suppression of 1/f noise and a low noise density (35 nV/√Hz) down to the DC-threshold. Common current sensors may be replaced with this technology whose one output is likewise analog. The power supply requirements are also far lower than for standard topologies as only a single supply is needed.

EPE-PEMC 2008 - Topic: Measurements, Sensors and Observing Techniques
You are here: EPE Documents > 04 - EPE-PEMC Conference Proceedings > EPE-PEMC 2008 - Conference > EPE-PEMC 2008 - Topic: Measurements, Sensors and Observing Techniques
	[return to parent folder]

	A Development System for Testing Integrated Circuits Used for Power and Energy Measurements By VladimirĆuk	[View] [Download]
Abstract: A development system for testing integrated circuits used for power and energy measurements is presented in the paper. System is based on a DSP board, a data acquisition (DAQ) board and a computer with a real time mathematical model. The aim of the paper is to provide observing of measurement accuracy in the laboratory and to simulate different conditions with the "phantom load" technique: nonlinearity, high-order harmonics, phase unbalance, voltage sag, etc.

	A New, Ultra-Low-Cost Power Quality and Energy Measurement Technology By Alex McEachern	[View] [Download]
Abstract: IEC 61000-4-30 is an excellent standard that ensures that all compliant power quality instruments, regardless of manufacturer, will produce the same results when connected to the same signal. However, instruments that comply with the Class A requirements of this standard have, until now, been too expensive for common use. Now a new set of technologies developed by an American company, in cooperation with a Japanese company, demonstrate that it is possible to manufacture three-phase power quality instruments that are fully compliant with the Class A requirements of IEC 61000-4-30 at ultra-low-cost to allow putting this monitoring devices even at entry levels of individual loads. The development uses technologies from several fields that have not previously been related to power quality, including digital cameras, power-over-ethernet, mobile phones, and submarine sonar systems. These new technologies have been packaged in a demonstration instrument, and may be licensed to instrument manufacturers as well. This allows gathering power quality and energy consumption information throughout manufacturing facilities or commercial buildings.

	Application of Speed and Load Torque Observes in High Speed Train By Jaroslaw Guzinski	[View] [Download]
Abstract: This paper presents a solution for observer based diagnostic system in high speed train with induction motor. The concept of the diagnostic system is dedicated to the mechanical part of the drive. The system is monitoring both motor speed sensor and torque transmission system. In case of speed sensor fault the control system could be switched into sensorless mode. Monitoring of torque Transmission system allows to limit the motor torque in case of serious problem and gives an information to maintenance center for testing the suspected gear. The proposed system was verified by simulation and in test bench for 1.2 MW rail induction motor.

	Asynchronous Machine Stator Resistance Estimation Using Integrated PWM Modulator and Sampler Unit as FPGA Application By Dag Samuelsen	[View] [Download]
Abstract: The paper demonstrates how a simple, low-cost and effective stator resistance estimation scheme for FPGA can be employed, utilizing the large degree of freedom a FPGA impose with regard to system design, while at the same time conform to the constraints the same technology infer. In a computing system, a FPGA removes the limitations of the Von Neuman-architecture. Although the (Super) Harward architecture, used by most DSP processors, relieve this limitations, this is not anywhere near the power of the parallel computing capability of FPGA. A FPGA is at the same time somewhat limited with regard to complexity of mathematical operations. Although this limitations has been removed with the introduction of FPGA with embedded CPU, there are still reasons for keeping the design simple, when overall cost should kept low. The estimator has been tested on an asynchronous machine, with satisfying results.

	Design of an FPGA-Based Real-Time Simulator for Electrical System By I. Bahri	[View] [Download]
Abstract: This paper deals with a Real-Time Simulation (RTS) able to accurately reproduce an electrical system in real-time. The RTS proposed architecture is written in VHDL and implemented in a Field Programmable Gate Array (FPGA) device. Multi-sampling approach is adopted allowing a real-time functioning with different time-steps and different operating conditions with minimized lost of accuracy. The proposed concept is illustrated by the RTS of each of a three-phase RLE load performed with a very short time step of 2.5 μs, an inverter, the measurement system and the hysteresis current controllers. Comparison with experimental results shows the high performances of this RTS.

	Development of Monitoring System for Series HEV Bus with Touch Panel By Tae-Won Chun	[View] [Download]
Abstract: In this paper, the monitoring strategies for a series hybrid electric vehicle (SHEV) bus are suggested for the optimal operation of powertrain and detection of abnormal conditions during the initial development of hybrid technologies. The monitoring system receives the messages from four control modules in the SHEV bus through a CAN, and then displays the data in the messages on a touch panel. In addition, all gauges and the on/off switching state of a set of telltale lamps are indicated. The monitoring system is implemented by both the 32-bit DSP and touch panel, and it is installed and tested on the real SHEV bus.

	Injection of a Carrier with Higher than the PWM Frequency for Sensorless Position Detection in PM Synchronous Motors By Roberto Leidhold	[View] [Download]
Abstract: The injection of an alternating carrier allows detecting the rotor position in PM synchronous motors. It is usually injected through the PWM, being therefore limited to about 1/5 of the switching frequency. By increasing the carrier frequency beyond the switching one, the bandwidth of the position observer can be significantly increased and audible noise can be reduced, among other advantages. A method is proposed to inject a carrier with a higher than the PWM frequency by coupling an external source through a transformer and a filter. An analysis of the advantages and difficulties, as well as experimental results, are presented.

	Nonlinear Dynamical Feedback for Motion Control of Magnetic Levitation System By Jerzy Baranowski and Pawel Piatek	[View] [Download]
Abstract: For fast, nonlinear and unstable dynamical systems, such as magnetic levitation, high quality of control is essential. Such control can be generated by different feedback structures, most of which require measurements of velocities or derivatives of the system output. In case of magnetic levitation the velocity of levitating object (a ferromagnetic sphere) is not measured. That is the reason for application of state observers which along with different controllers will create a nonlinear dynamical feedback structure. In this paper we will consider two such structures - PID controller with a nonlinear feed-forward and a cascade linearising feedback using two nonlinear state observers: High-Gain observer (HGO) and an observer with reduced, linear error dynamics (abbreviated as RO). Operation of these control algorithms will be compared with a classical PID structure, derivative part of which will be realised either as a finite difference or with an observer.

	Parallel Fixed Point FPGA Implementation of Sensorless Induction Motor Torque Control By Jacek D. Lis and Czeslaw T. Kowalski	[View] [Download]
Abstract: The paper deals with the FPGA implementation of an sensorless motor control application. The parallel processing approach is described. Few issues concerning the implementation are discussed. The method for the qualitative analysis of the considered state observer's sensitivity to the variations of the induction motor equivalent circuit parameters is presented. The experimental tests of the FPGA based implementation of the whole control structure of the sensorless DTC drive system are demonstrated.

	Position Estimator including Saturation and Iron Losses for Encoder Fault Detection of Doubly-Fed Induction Machine By Kai Rothenhagen	[View] [Download]
Abstract: Fault tolerance is gaining interest to increase reliability and availability, for example for distributed energy systems. Doubly fed induction generators need rotor position information for high performance control. As part of a multi-sensor fault tolerant generator system, fault tolerance of the position sensor is presented, using a position estimator. A known position estimator is improved and thoroughly described, including effects of machine saturation and iron losses. The fault detection and isolation is described and the reconfiguration from encoder to sensorless operation is shown. Measurements are provided and show good and fast results. Steady state properties of encoder and sensorless operation are compared.

	Rotor Time Constant Adaptation Using Radial Basis Function Network By Pavel Brandstetter	[View] [Download]
Abstract: Our intention here was to highlight a replacement of adaptation algorithm in MRAS by the help of alternative artificial neural network (ANN) which has received great attention in recent years. The main objective was to find and design some alternative neural network within the electric drive control. After a short discussion of hardware components, an overview of Radial Basis Function (RBF) neural networks will be given. Digital signal processors TMS320F2812 are used for these electric drives control applications. The hardware accessories used within the electric control drive included: interface board for the signal processor kit-developed in our department, and an 8bit data-transfer microprocessor for data acquisition. The interface of the DSP is a general-purpose control system for power converters in the electric drives. The next section briefly outlines the estimation of the rotor time constant, which is necessary for the so-called current model. The current model is used in the vector control of the induction motor and is utilized to determine the quantities for the transformation from the stationary reference frame into the reference frame, which is oriented on the rotor flux space vector. The estimation of the rotor time constant for the adaptive model of MRAS is created with the support of a PI-controller which is then replaced with the Radial Basis Function network. The final section presents simulations results, which have been performed in the Matlab-Simulink software.

	Speed and Position Estimation of SRM By Konrad Urbanski	[View] [Download]
Abstract: The paper deals with the problem of speed and position estimation in SRM drive equipped with hysteresis band current controller. Instead of measured current the observer utilize reference current. The voltage is calculated from switching ontime. A speed observer structure which uses estimated back EMF and current of each phase is presented. The shaft position is integrated from estimated speed signal.

	State and Parameter Estimation in a Hydraulic System - Moving Horizon Approach By Jerzy Baranowski	[View] [Download]
Abstract: In most control systems the best quality of control can be achieved if an exact model of a plant is known and if disturbances-free and continuous (instead of discrete) measurements of all its state space variables are available. Since it is seldom the case in real-life installations, state observers, adapting (parameters identification) algorithms, anti-noise filters and continuous signal estimators must be often employed. The paper describes an application of the moving horizon estimation (MHE) and continuous state estimation from discrete output measurements (CSEDOM) based method to a laboratory hydraulic three-tank system. The resulting algorithm encompasses all the four above-mentioned mechanisms (state observation, parameters identification, disturbances filtration and continuous state estimation) and can be used for nonlinear systems as well, which is the case in the presented article. The paper provides a detailed explanation of how the MHE and CSEDOMmethods were adapted to be applicable to the three-tank system. Results of computer simulations and practical laboratory experiments are also included.

	Study About the Possibility of Electrodes Motion Control in the EAF Based on Adaptive Impedance Control By Manuela Panoiu	[View] [Download]
Abstract: The paper presents a study about the possibility of adaptive process control in three phased electric arc furnace. The method is based on the electrodes motion control. The control principle is depending on impedance of the electric arc. The method proposed use a data acquisition board whose input signals are taken from electric arc. These signals allow the calculation of electric arc impedance. Using a numeric computer, it can be commands the control of electrodes position independently on each one of three phases. We propose to use a static frequency converter on each phase to control the electrodes motion.

	Technologies of Current Sensors Suitable for Hot High Density Power Electronics By Filip Grecki	[View] [Download]
Abstract: The paper describes the review of technologies of current sensors dedicated for high temperature power electronics. Two solutions are taken into consideration as the drive system and DC/DC converter implemented in Hybrid and Electric cars requires different parameters of current measurement system - the current range and switching frequency are various in both cases. Demands for current sensors, ideas of basic system are described.

	Transducerless Speed Control with Initial Position Detection for Low Cost PMSM Drives By Roman Filka	[View] [Download]
Abstract: This paper presents an approach for vector control of IPM synchronous motor without position transducer, applicable for low cost PMSM drives with unpredictable load and inertia. To achieve correct drive operation from zero speed, two different techniques are combined with crossover function, based on the speed reference. The rotor initial position is determined prior the control action, for the drive to deliver the full start up torque. Since back-EMF observer estimations are insufficiently accurate under limited angular speed, the zero speed startup and low speed acceleration is used. The back-EMF observer detects the generated motor voltages induced by the permanent magnets. An angle tracking observer uses the back-EMF signals to calculate the position and speed of the rotor. The experimental results based on dsp MC56F8025 show sufficient performance for washing machine, pumps, and fan applications.

	Wide Range Low Noise Current Sensor By F. Richter and C. Sourkounis	[View] [Download]
Abstract: Compared to conventional current sensors, the proposed topology is advantageous because of its high resolution throughout its full measurement range, thus reducing offsets to a minimum. This aim is reached through active offset compensation using an analog/digital chopper/de-chopper. A further advantage is the excellent suppression of 1/f noise and a low noise density (35 nV/√Hz) down to the DC-threshold. Common current sensors may be replaced with this technology whose one output is likewise analog. The power supply requirements are also far lower than for standard topologies as only a single supply is needed.