Speed Tracking Performance Research Articles

Nonlinear control of interior permanent-magnet synchronous motor

This paper presents a novel speed control technique for an interior permanent-magnet synchronous motor (IPMSM) drive based on newly developed adaptive backstepping technique. The proposed stabilizing feedback law for the IPMSM drive is shown to be globally asymptotically stable in the context of Lyapunov theory. The adaptive backstepping technique takes system nonlinearities into account in the control system design stage. The detailed derivations of the control laws have been given for controller design. The complete IPMSM drive incorporating the proposed backstepping control technique has been successfully implemented in real-time using digital signal processor board DS1102 for a laboratory 1-hp motor. The performance of the proposed drive is investigated both in experiment and simulation at different operating conditions. It is found that the proposed control technique provides a good speed tracking performance for the IPMSM drive ensuring the global stability.

Theoretical and experimental comparison of indirect field-oriented controllers for induction motors

A theoretical and experimental comparison between standard and recently-developed improved indirect field-oriented controllers for induction motors is presented. It is shown that standard indirect field-oriented control algorithm provides asymptotic speed and flux regulation, while the improved one guarantees global exponential speed-flux tracking under condition of constant load torque. The difference between the flux sub-system design for the two controllers is analyzed. It is shown that the improved controller provides closed loop properties for flux subsystem when motor is rotating, leading to robust stabilization of the rotor flux vector space position and robust tracking of its modulus. It is demonstrated that both controllers have similar complexity and can be tuned using standard procedure for cascaded systems. Intensive experimental study shows that improved controller provides about one order higher speed tracking performance as compared with standard solution. Moreover, improved robustness with respect to rotor parameters variation leads to improved energy efficiency and robust stabilization of dynamic performance.

Adaptive Continuously Variable Compression Braking Control for Heavy-Duty Vehicles

Modern heavy-duty vehicles are equipped with compression braking mechanisms that augment their braking capability and reduce wear of the conventional friction brakes. In this paper we consider a heavy-duty vehicle equipped with a continuously variable compression braking mechanism. The variability of the compression braking torque is achieved through controlling a secondary opening of the exhaust valve of the vehicle’s turbocharged diesel engine using a variable valve timing actuator. A model reference adaptive controller is designed to ensure good vehicle speed tracking performance in brake-by-wire driving scenarios in presence of large payload and road grade variations. The adaptive controller is integrated with backstepping procedure to account for compression braking actuator dynamics, with observers for various unmeasured quantities and with compensation schemes for actuator saturation. In addition to speed tracking, the vehicle mass and road grade are simultaneously estimated if persistence of excitation-type conditions hold. The final version of the controller is successfully evaluated on a high order crank angle model of a vehicle with a six-cylinder engine.

Nonlinear MIMO Speed Sensorless Controller for DC Motor Field Weakening

This paper addresses speed control of a separately excited DC motor (SEDCM) in nonlinear field weakening region. Input output linearization (IOL) technique is used to deal with the motor system with considerable nonlinearity, and a nonlinear multi-input multi-output (MIMO) speed tracking controller is developed for constant power field weakening. The effects of decoupling and linearization permit the controller to be implemented and operated at any desired field weakening point of operation. The control scheme combining this controller with nonlinear speed/load torque observer is, in particular, proposed for speed sensorless operation. Computer simulations are presented to show speed tracking performance of the proposed overall scheme.

A decomposed control scheme for vision-guided manipulators curve tracking

This letter presents a robot control algorithm for vision guided curve tracking using orthogonal decomposition control method. It was implemented in a glass-cutting direct-drive robot for the drawing curve input with high speed and smooth tracking performance.

Fuzzy logic enhanced speed control of an indirect field-oriented induction machine drive

Field orientation control (FOC) of induction machines has permitted fast transient response by decoupled torque and flux control. However, field orientation detuning caused by parameter variations is a major difficulty for indirect FOC methods. Traditional probability density function (PID) controllers have trouble meeting a wide range of speed tracking performance even when proper field orientation is achieved. PID controller performance is severely degraded when detuning occurs. This paper presents a fuzzy logic design approach that can meet the speed tracking requirements even when detuning occurs. Computer simulations and experimental results obtained via a general-purpose digital signal processor (DSP) system are presented.

H ∞ Speed Controller Design for Hot Rolling Mill Drives

An H ∞ speed controller design method for hot rolling mill drives, #4 drive system in #2 hot rolling mill of POSCO, is proposed. A weighted mixed sensitivity minimization method is used for obtaining an H ∞ speed controller, and loop shaping is used for improving speed tracking performance. The designed speed controller guarantees the robust stability of closed loop system against parameter variation and minimizes the effects of disturbance by change of load torques. And simulation results is given to validate the proposed design method.

What limits high speed tracking performance?

Adaptive Model Theory (AMT) is a computational theory of the information processing performed by the human nervous system in control of movement. The behaviour of six subjects performing visual pursuit tracking was measured as a function of the bandwidth of the target signal. Gain and phase of the relationship between target and response signals were plotted as a function of target signal bandwidth as the bandwidth increased from 0.1–3.9 Hz. Performance characteristics for human subjects were compared with those of computer simulations of tracking behaviour based on AMT. The computer simulations compensated for a 300 ms reaction time delay by predicting the future position of the target 300 ms ahead. Predictions were achieved by an adaptive filter circuit which automatically tuned its weights to generate the best possible predictions by minimizing the variance of the prediction errors. The influence of prediction on tracking behaviour was assessed by running the computer simulations both with and without target signal prediction. Gain and phase frequency response curves for all subjects varied as a function of target signal bandwidth in a manner similar to the computer simulations with prediction. The data support the view that the human nervous system includes adaptive neural filters able to generate predictions of future values of sensory signals by tuning themselves to minimize the variance of prediction errors, as proposed in the AMT.

A Robust Servo-Electronic Controller for Brake Force Distribution

In this paper a control system which achieves ideal brake force distribution between the front and the rear wheels of a vehicle during normal braking is studied. Ideal brake proportioning is achieved by dynamically controlling the rear-wheel speed to track the front-wheel speed. Electro-hydraulic brake actuators, which are installed at the rear brakes of the vehicle, are used to modulate the brake-line pressure. A simple linear model of the actuators was developed. This model is derived from experimental response data. Based on this model, a robust servomechanism controller, which achieves ideal brake proportioning by rear-wheel speed control, is designed, implemented, and tested. Test results indicate that the robust servo-mechanism controller achieves a very good wheel speed tracking performance.