The main contribution of this paper is the verification of a new train control system applied to the drive with a.c. motors that is energy near optimal with respect to electrical and mechanical ...energy minimization. All simulations are related to the one traction motor yielding its best exploitation. Load torque treated as a state variable consists of constant, linear, and quadratic components as a function of rotor speed. The required performance of the energy-saving control is rendered straightforward using precomputed energy optimal state variables or a prediction of losses for a symmetrical trapezoidal speed profile as the second alternative. An energy-saving reference position generator provides the state variables, which are faithfully followed by a feedback control based on field orientation, which is completed with a matched zero dynamic lag pre-compensator yielding prescribed closed-loop dynamics. Simulation results mutually compared confirm the capability of an overall drive control system to follow generated state variables for two different service conditions and the possibility of energy savings.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Nowadays trends in railway transportation are improvement of passengers comfort, safety, speed and reliability of transportation. This paper deals with improvement of aforementioned performances from ...the traction drive view. The most often exploited drives system is the induction motor supplied from inverter therefore strategy of its control has direct influence on reliability. Control techniques exploited in traction drives are ‘field oriented control’ (FOC) and ‘direct torque control’ (DTC). For investigation of the drive performances controlled with these two techniques the parameters of 152kW induction motor are used. The comparison can be done on various criteria, but in this paper comparison will be focused on influence of key parameters including magnetizing inductance Lm, rotor inductance Lr and rotor resistance Rr. The study is done by simulation using the Simulink. The simulation and evaluation of both control strategies are performed using actual parameters of induction machine fed by an IGBT PWM inverter.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The main contribution of this paper is a new rest-to-rest position control system for use with electric drives employing a.c. motors that is near-optimal with respect to combined electrical and ...frictional energy waste minimization. The friction has constant, linear, and quadratic components with respect to the rotor speed. The closeness to optimality is assessed by simulation, comparing the energy loss of the new control system with that predicted by computed optimal controls. The application of the near-optimal control system is rendered straightforward by using a symmetrical trapezoidal speed-time profile. This is provided by an energy saving reference position generator whose output is faithfully followed by means of a feedback control law based on forced dynamics control yielding prescribed closed loop dynamics, together with a matched zero dynamic lag precompensator. For load torque consisting of constant, linear, and quadratic components also maneuver time is optimized if it can be chosen arbitrary. Two case studies, one applied to position control of rotational drive and second one applied to train movement, confirm the possibilities of achieving energy savings.
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FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
Euler-Lagrange optimization method is exploited here to develop energy saving position control strategy valid for a.c. drives. The optimization principle respects copper losses minimization only. ...Boundary value problem for Euler-Lagrange equations is solved by Differential transformation method (DTM).
Position control system of moderate precision based on 'forced dynamics control' for the drive with significant vibration modes is described. To exploit the only position sensor on the motor side, ...all necessary control variables are estimated in observers based on motor position and stator current measurements. The designed controller is of a cascade structure, comprising an inner speed control loop, which respects vector control principles and an outer position control loop, which is designed to control load angle with prescribed dynamics in the presence of flexible modes. Simulations of the overall control system indicate that the proposed control system exhibits the desired robustness and therefore warrants further development and experimental investigation.
Purpose - The purpose of this paper is to discuss the design and verification of a new control algorithm for the drive with permanent magnet synchronous motor (PMSM) and flexible coupling based on ..."Forced dynamics control". Control laws are derived and tested for the rotor and load angle control and achieve non-oscillatory position step response with a specified settling time.Design methodology approach - "Forced dynamics control" is a new control technique based on feedback linearization which forces rotor or load position to follow demanded position with prescribed closed-loop dynamics. The proposed control structure is developed in two steps: first, the feedback linearisation is applied to the rotor speed and then similar technique is used for position control loop.Findings - The proposed controller is of the cascade structure, comprising an inner speed control loop, respecting vector control principles and outer position control loop designed to control the rotor or load angle, respectively. Estimates of load torques acting on the motor and load side as inputs of control algorithms are produced in observers and used to compensate disturbances offering a certain degree of robustness. Preliminary experiments confirm that proposed system follows the ideal closed-loop dynamics with moderate accuracy.Research limitations implications - The focus is on experimental verification of the position control of flexible PMSM drive with two position sensors and moderate precision, where the oscillations due to hardware setup, achieved sampling frequency and corresponding observers adjustment are limited up to 50 rad s−1.Practical implications - The designed control structure can substantially improve control performance of industrial plants subjects to torsion oscillations.Originality value - Experimental results of a novel control structure for the PMSM drives with torsion oscillations are sufficiently promising and confirmed that the rotor and load angle responses follow the prescribed ones fairly closely.
U radu je opisano upravljanje sustavom pozicioniranja srednje preciznosti s izraženim vibracijskim modovima korištenjem metodologije prisilnog upravljanja dinamikom. Kako bi se iskoristio senzor ...pozicije na strani motora, sve potrebne varijable stanja estimiraju se na temelju mjerenja pozicije motora i statorskih struja. Projektirani regulator je kaskadne strukture, s unutarnjom petljom po brzini vrtnje koja se temelji na principima vektorskog upravljanja, i vanjskom petljom po poziciji za upravljanje kutom tereta s definiranom dinamikom u prisustvu slabo prigušenih modova. Simulacijski rezultati cjelokupnog sustava upravljanja potvr.uju da predloženi sustav upravljanja posjeduje željenu robusnost i time opravdava budući razvoj i eksperimentalna istraživanja.
Purpose
The main purpose of this paper is to evaluate the two energy saving position control strategies for AC drives valid for a wide range of boundary conditions including an analysis of their ...energy expenses.
Design/methodology/approach
For energy demands analysis, the optimal energy control based on mechanical and electrical losses minimization is compared with the near-optimal one based on symmetrical trapezoidal speed profile. Both control strategies respect prescribed maneuver time and define acceleration profile for preplanned rest-to-rest maneuver.
Findings
Presented simulations confirm lower total energy expenditures of energy optimal control if compared with near-optimal one, but the differences are only small due to the fact that two energy saving strategies are compared.
Research limitations/implications
Developed overall control system consisting of energy saving profile generator, pre-compensator and position control system respecting principles of field-oriented control is capable to track precomputed state variables precisely.
Practical implications
Energy demands of both control strategies are verified and compared to simulations and preliminary experiments. The possibilities of energy savings were confirmed for both control strategies.
Originality/value
Experimental verification of designed control structure is sufficiently promising and confirmed assumed energy savings.
A decomposed sliding mode control of the drive with an interior permanent magnet synchronous motor and flexible coupling is presented. Decomposition exploits principles of vector control to divide ...motor into channel for control of magnetic flux and channel for control of torque separately. Sliding mode control principles are exploited to keep demanded value of magnetic flux and to control load angle in the presence of vibration modes and external disturbances. To obtain continues voltage as a control variable a smoothing integrator follows signum function in both channels. As a modification the switching governed by signum function is replaced by the high gain including rearrangement of the control system block diagram. The simulations indicate that the control system yields the desired robustness and further investigations are recommended.
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FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
Position Control of PMSM in Sliding Mode Bris, Peter; Vittek, Jan; Makys, Pavol
Advances in electrical and electronic engineering,
03/2008, Volume:
7, Issue:
1-2
Journal Article
Peer reviewed
Open access
In the paper control of linear permanent magnet synchronous motor (PMSM) based on the principles of sliding mode control (SMC) with respect of vector control principles is carried out. The presented ...simulations comprise position quantization due to assumed experimental verification on the bench which consists of linear PMSM and incremental position sensor. Simulation results compare two methods for obtaining of position derivatives needed for SMC algorithm. The first method exploits a filtering observer and second one uses numerical derivations and first order filters.
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