In this paper, we propose a feedback gain design method for the full-order flux observer with ada... more In this paper, we propose a feedback gain design method for the full-order flux observer with adaptive speed loop, that minimizes the instability region of an adaptive speed estimator to a line in the torque/speed plane. We analyze its convergence performance and propose a pole assignment method allowing to take into account dynamics constraints and stability in regenerating mode at
IOP Conference Series: Materials Science and Engineering, 2019
Significant implementations and encouraging results have already been achieved using visible ligh... more Significant implementations and encouraging results have already been achieved using visible light communication (VLC) technology for different applications from indoor to free space optics (FSO) and even underwater communication. The LED light fixtures are about to be used with dual functionality - illumination and fast wireless data communication - and when the technology will become mature enough, the general costs for both will considerably decrease. However, especially due to a complex multipath channel impulse response (CIR) evaluation, there are few research in VLC applied in industrial environments. At the same time, in the non-Line of Sight (NLoS) VLC setup with mobile optical transmitter (oTx) and fixed optical receiver (oRx) considered here, both the path loss and multipath-induced dispersion significantly limits the link performance. In this paper, we investigate the CIR into indoor industrial environments. We take into consideration both Intrinsic Optical Properties in ...
Analele Universităţii "Eftimie Murgu" Reşiţa: Fascicola I, Inginerie, 2014
The paper deals with a new type of observer for the rotor flux and speed of the induction motor. ... more The paper deals with a new type of observer for the rotor flux and speed of the induction motor. The new observer is designed to be used within a speed sensorless direct rotor field oriented control of induction motors. In order to present the performances of the new observer, it was compared to extended Luenberger observer. The comparative analysis was simulated using Matlab – Simulink – dSPACE platform.
In the paper we present the stability study of the Kalman estimator used in a vectorial drive sys... more In the paper we present the stability study of the Kalman estimator used in a vectorial drive system of an induction motor with short-circuited rotor. We consider that the control system for speed is a vectorial system with direct orientation after the rotor flux (DFOC). Although there are suggestive experimental results, the implementation of such a system containing a Kalman filter generates serious problems because of the tuning of the covariant matrixes of the measurement noise and the process noise. Also the solving of the Riccati equations in real time is difficult. These problems, as well as the simplifier hypothesis from the determination of the mathematical model on the states space of the induction motor and the modification of the rotor resistance by temperature lead to the decrease of the estimator and control system performances. Therefore you must implement an algorithm for research of the estimator stability. This algorithm has to hold count of the sampling step of su...
This paper analyzes the case of designing an exoskeleton for people with right arm mobility impai... more This paper analyzes the case of designing an exoskeleton for people with right arm mobility impairments. The type of exoskeleton considered consists of three joints, one of translation along the spine and two of rotation for the arm of the exoskeleton. The first approach presented is for the people who have the intention to move at the level of the muscles, which can be detected with the help of non-invasive EMG sensors, but cannot sustain the movement for a long time. In this approach within the control system there are two components. The first is computational only, which includes the Denavit-Hartenberg models: direct for the human arm and inverted for the exoskeleton. The second component is an ANN-based estimator that estimates the arm’s movement angle based on the acquired EMG signals. The second approach presented in the paper is for people who cannot voluntarily perform the arm movement. For this case, an exoskeleton control system was designed based on the training of an AN...
2021 International Conference on Applied and Theoretical Electricity (ICATE), 2021
This paper presents a new approach in speed and rotor flux estimation for induction motors. In th... more This paper presents a new approach in speed and rotor flux estimation for induction motors. In this sense, the rotor flux is estimated with the help of a new full-order state observer, and the speed is estimated with the help of a back-emf MRAS observer. For the proposed observer its dynamic performances and stability are analyzed. The paper also presents the value range of the proportionality coefficient in the component of the observer gain matrix. The validity of the observer are proved by numerical simulation in Matlab-Simulink.
2019 8th International Conference on Modern Power Systems (MPS), 2019
In this article, a comparative study is being carried out between the extended Gopinath observer ... more In this article, a comparative study is being carried out between the extended Gopinath observer (EGO) versus the assembly consisting of the MRAS speed observer and the reduced order Gopinath observer, used in estimating dq components of the rotor flux phasor. Both observers are designed for sensorless vector control systems of the induction motors. Comparative analysis is performed by simulation using the Matlab-Simulink programming environment.
2019 8th International Conference on Modern Power Systems (MPS), 2019
We present in this paper a comparative study between a PI speed controller and the two-degree-of-... more We present in this paper a comparative study between a PI speed controller and the two-degree-of-freedom (2DOF) speed controller, used in a sensorless vector control system with direct orientation after the rotor flux. The simultaneous estimation of the speed and rotor flux is done by using an extended Gopinath Observer (EGO). Comparative analysis is performed by using simulation in the Matlab-Simulink programming environment.
2018 International Conference on Applied and Theoretical Electricity (ICATE), 2018
The article presents a new method for on-line estimating the electrical parameters of an inductio... more The article presents a new method for on-line estimating the electrical parameters of an induction motor. In this regard, a Luenberger observer is used, which is online adapted according to the estimated electrical parameters. The stator and rotor resistance, stator inductance as well as dispersion coefficient are estimated based on some adaptive methods. The estimation method is tested and validated by simulation in Matlab-Simulink.
2021 International Conference on Electromechanical and Energy Systems (SIELMEN), 2021
This article presents a new gain matrix of the Luenberger observer determined based on the parall... more This article presents a new gain matrix of the Luenberger observer determined based on the parallel mathematical model of the induction motor with iron loss. The Luenberger observer estimates the stator current and rotor flux of an induction motor. The testing of the proposed observer is done both in the open loop and in the closed loop of a vector control system. All tests are performed by simulation in Simulink.
2019 International Conference on Electromechanical and Energy Systems (SIELMEN), 2019
The article presents a comparison a two observers used in the simultaneous estimation of the spee... more The article presents a comparison a two observers used in the simultaneous estimation of the speed, position and phasor modulus of the rotor flux of an induction motor. The analysed observers are: extended Gopinath observer (EGO) and assembly consisting of the reduced order Gopinath observer and the Peng speed observer. Both observers are used in sensorless vector control systems with direct rotor flux orientation. Comparative tests are realized by numerical simulation using the Matlab-Simulink.
An accurate channel model is both essential and challenging when designing a reliable wireless Vi... more An accurate channel model is both essential and challenging when designing a reliable wireless Visible Light Communication (VLC) system. Modeling the channel in a restricted and harsh environment such as an underground mine, is even more difficult. The objective in our work is to investigate a suitable design of a VLC link for an underground environment, while providing a reliable connectivity between the optical transmitter and optical receiver. In this paper, we present an experimental study that aims to determine a general model of an underground mine optical channel. Considering that the underground optical channel has a nonlinear dynamic behavior described by a nonlinear autoregressive exogenous (NARX) mathematical model, the system’s order is established with a feedforward neural network (NN), with a parallel architecture. In this work, in order to define a proper Underground Mine Optical Channel Model (UMOCM) for reliable VLC, we present an innovative approach based on a suit...
2021 9th International Conference on Modern Power Systems (MPS)
This paper presents a new technique of implementing the back-EMF MRAS speed observer used in sens... more This paper presents a new technique of implementing the back-EMF MRAS speed observer used in sensorless vector control systems with induction motors. The adjustable model of the speed observer is made on the basis of the estimated d-q components of the back electromotive forces (Back-EMF) using in this sense the afferent components the space vector of the rotor flux, obtained on the basis of the reduced order Gopinath observer. The testing and evaluation of the dynamic performances of the speed and rotor flux observers are by numerical simulation in Matlab-Simulink performed.
In this paper, we propose a feedback gain design method for the full-order flux observer with ada... more In this paper, we propose a feedback gain design method for the full-order flux observer with adaptive speed loop, that minimizes the instability region of an adaptive speed estimator to a line in the torque/speed plane. We analyze its convergence performance and propose a pole assignment method allowing to take into account dynamics constraints and stability in regenerating mode at
IOP Conference Series: Materials Science and Engineering, 2019
Significant implementations and encouraging results have already been achieved using visible ligh... more Significant implementations and encouraging results have already been achieved using visible light communication (VLC) technology for different applications from indoor to free space optics (FSO) and even underwater communication. The LED light fixtures are about to be used with dual functionality - illumination and fast wireless data communication - and when the technology will become mature enough, the general costs for both will considerably decrease. However, especially due to a complex multipath channel impulse response (CIR) evaluation, there are few research in VLC applied in industrial environments. At the same time, in the non-Line of Sight (NLoS) VLC setup with mobile optical transmitter (oTx) and fixed optical receiver (oRx) considered here, both the path loss and multipath-induced dispersion significantly limits the link performance. In this paper, we investigate the CIR into indoor industrial environments. We take into consideration both Intrinsic Optical Properties in ...
Analele Universităţii "Eftimie Murgu" Reşiţa: Fascicola I, Inginerie, 2014
The paper deals with a new type of observer for the rotor flux and speed of the induction motor. ... more The paper deals with a new type of observer for the rotor flux and speed of the induction motor. The new observer is designed to be used within a speed sensorless direct rotor field oriented control of induction motors. In order to present the performances of the new observer, it was compared to extended Luenberger observer. The comparative analysis was simulated using Matlab – Simulink – dSPACE platform.
In the paper we present the stability study of the Kalman estimator used in a vectorial drive sys... more In the paper we present the stability study of the Kalman estimator used in a vectorial drive system of an induction motor with short-circuited rotor. We consider that the control system for speed is a vectorial system with direct orientation after the rotor flux (DFOC). Although there are suggestive experimental results, the implementation of such a system containing a Kalman filter generates serious problems because of the tuning of the covariant matrixes of the measurement noise and the process noise. Also the solving of the Riccati equations in real time is difficult. These problems, as well as the simplifier hypothesis from the determination of the mathematical model on the states space of the induction motor and the modification of the rotor resistance by temperature lead to the decrease of the estimator and control system performances. Therefore you must implement an algorithm for research of the estimator stability. This algorithm has to hold count of the sampling step of su...
This paper analyzes the case of designing an exoskeleton for people with right arm mobility impai... more This paper analyzes the case of designing an exoskeleton for people with right arm mobility impairments. The type of exoskeleton considered consists of three joints, one of translation along the spine and two of rotation for the arm of the exoskeleton. The first approach presented is for the people who have the intention to move at the level of the muscles, which can be detected with the help of non-invasive EMG sensors, but cannot sustain the movement for a long time. In this approach within the control system there are two components. The first is computational only, which includes the Denavit-Hartenberg models: direct for the human arm and inverted for the exoskeleton. The second component is an ANN-based estimator that estimates the arm’s movement angle based on the acquired EMG signals. The second approach presented in the paper is for people who cannot voluntarily perform the arm movement. For this case, an exoskeleton control system was designed based on the training of an AN...
2021 International Conference on Applied and Theoretical Electricity (ICATE), 2021
This paper presents a new approach in speed and rotor flux estimation for induction motors. In th... more This paper presents a new approach in speed and rotor flux estimation for induction motors. In this sense, the rotor flux is estimated with the help of a new full-order state observer, and the speed is estimated with the help of a back-emf MRAS observer. For the proposed observer its dynamic performances and stability are analyzed. The paper also presents the value range of the proportionality coefficient in the component of the observer gain matrix. The validity of the observer are proved by numerical simulation in Matlab-Simulink.
2019 8th International Conference on Modern Power Systems (MPS), 2019
In this article, a comparative study is being carried out between the extended Gopinath observer ... more In this article, a comparative study is being carried out between the extended Gopinath observer (EGO) versus the assembly consisting of the MRAS speed observer and the reduced order Gopinath observer, used in estimating dq components of the rotor flux phasor. Both observers are designed for sensorless vector control systems of the induction motors. Comparative analysis is performed by simulation using the Matlab-Simulink programming environment.
2019 8th International Conference on Modern Power Systems (MPS), 2019
We present in this paper a comparative study between a PI speed controller and the two-degree-of-... more We present in this paper a comparative study between a PI speed controller and the two-degree-of-freedom (2DOF) speed controller, used in a sensorless vector control system with direct orientation after the rotor flux. The simultaneous estimation of the speed and rotor flux is done by using an extended Gopinath Observer (EGO). Comparative analysis is performed by using simulation in the Matlab-Simulink programming environment.
2018 International Conference on Applied and Theoretical Electricity (ICATE), 2018
The article presents a new method for on-line estimating the electrical parameters of an inductio... more The article presents a new method for on-line estimating the electrical parameters of an induction motor. In this regard, a Luenberger observer is used, which is online adapted according to the estimated electrical parameters. The stator and rotor resistance, stator inductance as well as dispersion coefficient are estimated based on some adaptive methods. The estimation method is tested and validated by simulation in Matlab-Simulink.
2021 International Conference on Electromechanical and Energy Systems (SIELMEN), 2021
This article presents a new gain matrix of the Luenberger observer determined based on the parall... more This article presents a new gain matrix of the Luenberger observer determined based on the parallel mathematical model of the induction motor with iron loss. The Luenberger observer estimates the stator current and rotor flux of an induction motor. The testing of the proposed observer is done both in the open loop and in the closed loop of a vector control system. All tests are performed by simulation in Simulink.
2019 International Conference on Electromechanical and Energy Systems (SIELMEN), 2019
The article presents a comparison a two observers used in the simultaneous estimation of the spee... more The article presents a comparison a two observers used in the simultaneous estimation of the speed, position and phasor modulus of the rotor flux of an induction motor. The analysed observers are: extended Gopinath observer (EGO) and assembly consisting of the reduced order Gopinath observer and the Peng speed observer. Both observers are used in sensorless vector control systems with direct rotor flux orientation. Comparative tests are realized by numerical simulation using the Matlab-Simulink.
An accurate channel model is both essential and challenging when designing a reliable wireless Vi... more An accurate channel model is both essential and challenging when designing a reliable wireless Visible Light Communication (VLC) system. Modeling the channel in a restricted and harsh environment such as an underground mine, is even more difficult. The objective in our work is to investigate a suitable design of a VLC link for an underground environment, while providing a reliable connectivity between the optical transmitter and optical receiver. In this paper, we present an experimental study that aims to determine a general model of an underground mine optical channel. Considering that the underground optical channel has a nonlinear dynamic behavior described by a nonlinear autoregressive exogenous (NARX) mathematical model, the system’s order is established with a feedforward neural network (NN), with a parallel architecture. In this work, in order to define a proper Underground Mine Optical Channel Model (UMOCM) for reliable VLC, we present an innovative approach based on a suit...
2021 9th International Conference on Modern Power Systems (MPS)
This paper presents a new technique of implementing the back-EMF MRAS speed observer used in sens... more This paper presents a new technique of implementing the back-EMF MRAS speed observer used in sensorless vector control systems with induction motors. The adjustable model of the speed observer is made on the basis of the estimated d-q components of the back electromotive forces (Back-EMF) using in this sense the afferent components the space vector of the rotor flux, obtained on the basis of the reduced order Gopinath observer. The testing and evaluation of the dynamic performances of the speed and rotor flux observers are by numerical simulation in Matlab-Simulink performed.
Uploads
Papers by Olimpiu Stoicuta