This paper targets the main current trend in automotive motor control applications, i.e., six-phase permanent−magnet synchronous machines. Multiphase machines have been studied for more than one ...decade, but they are currently becoming more and more important for automotive technology. Increased safety and improved reliability are the two main reasons why six-phase machines conquer safety-critical motor control applications. The paper provides a detailed description, analysis, and comparison of two field-oriented control strategies for six-phase machines. The article consists of four main parts: (1) a general introduction of the application field of six-phase machines; (2) a description of two different field-oriented control techniques; (3) a presentation of the experimental results, e.g., frequency and step response analysis, as well as a comparison between a mathematical model and a real system; (4) a detailed comparison of strategies including pros and cons, with a strong focus on the main advantages.
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
Signal processing of the brushed DC motor current was developed in this paper to obtain information about a rotor speed from a measured motor current. The brushed DC motor current contains a signal ...with a frequency proportional to the rotor speed. This signal is the outcome of a commutation process occurring in the brushed DC motor, and it is called a ripple component. Since the number of ripples in the measured motor current per one rotation is constant, the rotor speed can be estimated. A discrete bandpass filter with a floating bandwidth was developed as the main part of signal processing. This new interpretation of the bandpass filter was used to extract a frequency of the ripple component from the measured motor current. This frequency was used to acquire information about the estimated rotor speed. The estimated speed was set as a feedback value to a cascade control structure to provide sensorless speed control. The advantages and limitations of this approach are presented in this paper. Based on simulations and experimental results, it was confirmed that the proposed sensorless speed control is robust, accurate, and works precisely in a wide range of speeds.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
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.
This paper proposes a novel constant power factor loop in the V/f control strategy with stabilization for a permanent magnet synchronous motor (PMSM). The advantage of such an algorithm is the ...independence of the machine parameters, which vary under different operational conditions, e.g., with temperature, magnetic core saturation, and skin-effect. Furthermore, it is a low-cost and simple-to-implement sensorless solution. The proposed strategy is compared against traditional sensorless FOC with a Luenberger-type back-electromotive force (EMF) observer, which can be designed based on the machine model. The output of this kind of observer is typically an error signal, which can be specified for position deviation, requiring phase-locked loop (PLL) algorithm implementation. Employing PLL, a rotor speed and position can be estimated from such an error. Therefore, it is a complex sensorless technique with high-performance microcontroller unit (MCU) requirements. Both strategies are deeply analyzed, mathematically described, and compared within the paper. At the end of the paper, these sensorless strategies are supported by experimental verification with a traction PMSM designed for golf cart applications, and the pros and cons of both techniques are discussed.
The paper contains PI controllers setting, for field oriented control of 6-phase machines with permanent magnets. Two basic and the mostly used approaches for current and speed control are discussed ...and compared to each other. The first approach is based on a one orthogonal system and second deals with two orthogonal systems. Mathematical models behaviour is analysed and verified by Matlab simulations.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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.
Ball on plate platform is a great tool for testing of various control techniques. This study provides a detailed design and comparison of three control structures for automatic stabilization of the ...ball´s location on plate and ball trajectory tracking. Namely PD controller, state space feedback and state space observer with state space feedback. All three methods are designed and practically compared. All structures have a common feature. It is the methodology for calculating the parameters of the controllers. Ball - on - plate mathematical model derived by Newton´s method and DC motor position loop control are also part of this article. For the authors of this article, this study is an opportunity to create an educative setup to explain the principles of basic control system for non - technical person and offers motivation to future students
Position tracking systems for AC drives offering high robustness to external load torques have been presented. A triple-loop cascade control structure was employed where the inner loop is a stator ...current control loop and the middle loop is a speed control loop based on the forced dynamic control and respecting vector control principles. Two alternative outer position control loop designs both of which respect prescribed dynamics and settling time of position have been developed. The former system prescribes also time constant of the speed control loop while the latter one respects time constant of speed control system developed independently. To enhance the tracking abilities of both control systems the dynamic lag pre-compensator has been included. Case studies of the both position control systems for time near-optimal control and energy near-optimal control have been presented. The tracking performances of the designed control systems were assessed based on comparisons of the experimental responses with the simulated responses of the ideal closed-loop system.
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