Showing papers in "IEEE Transactions on Industrial Electronics in 1984"
TL;DR: In this paper, a low-power breadboard operating at 200-300 kHz has been built for switching power supplies and battery chargers, which can operate in either the step-up or step-down mode.
Abstract: Transistor dc-dc converters which employ a resonant circuit are described. A resonant circuit is driven with square waves of current or voltage, and by adjusting the frequency around the resonant point, the voltage on the resonant components can be adjusted to any practical voltage level. By rectifying the voltage across the resonant elements, a dc voltage is obtained which can be either higher or lower than the input dc voltage to the converter. Thus, the converter can operate in either the step-up or step-down mode. In addition, the switching losses in the inverter devices and rectifiers are extremely low due to the sine waves that occur from the use of a resonant circuit (as opposed to square waves in a conventional converter); also, easier EMI filtering should result. In the voltage input version, the converter is able to use the parasitic diode associated with an FET or monolithic Darlington, while in the current input version, the converter needs the inverse blocking capability which can be obtained with an IGT or GTO device. A low-power breadboard operating at 200-300 kHz has been built. Two typical application areas are switching power supplies and battery chargers. The converter circuits offer improvements over conventional circuits due to their high efficiency (low switching losses), small reactive components (high-frequency operation), and their step-up/stepdown ability.
371 citations
TL;DR: This paper reviews the work done on PID/ST design, the major ideas are briefly discussed, and some specific algorithms presented.
Abstract: The appearance in the market of off-the-shelf PID self-tuning (PID/ST) controllers (see Cont. Eng., Oct. 1981) reflects the industry's need to satisfy increasingly stringent control objectives which can only be attained with adaptive algorithms. Further studies on the relatively mature adaptive control theory must be directed toward providing the field engineer with the fundamentals required to utilize this algorithm confidently and profitably. It is in this sense that the study of an adaptive version of the ubiquitous PID controller (with its unquestionably appealing characteristics) must be encouraged. This paper reviews the work done on PID/ST design, the major ideas are briefly discussed, and some specific algorithms presented. The performance of various PID/ST's is illustrated by simulated examples.
92 citations
TL;DR: In this paper, a new solar cell power supply system is presented, in which the boost type bidirectional dc-dc converter and the simple control circuit with a small monitor solar cell are employed to track the maximum power point of the solar array.
Abstract: A new solar cell power supply system is presented, in which the boost type bidirectional dc-dc converter and the simple control circuit with a small monitor solar cell are employed to track the maximum power point of the solar array. It is confirmed by the experiment that the new system has sufficiently precise tracking operation performance and satisfactorily high power efficiency. Also, a comparison of the power efficiencies is made theoretically, as well as experimentally, on the new and the conventional solar cell power supply systems. As a result, it is revealed that the new system is superior to the conventional one in the power efficiency.
81 citations
TL;DR: The easy to understand intrinsic model and analytical parameter estimation procedure produce a user-oriented model with common topology applicable to popular CADA programs such as SPICE2 and SUPER-SCEPTRE.
Abstract: The principle of SCR model parameter estimation from device specification sheets [7] is combined with a reduced version of the intrinsic SCR model [2] to provide improved computational efficiency and better simulation of device turn-off dynamics. The small element count makes computer-aided design and analysis (CADA) of circuits containing several SCR's more feasible. The easy to understand intrinsic model and analytical parameter estimation procedure produce a user-oriented model with common topology applicable to popular CADA programs such as SPICE2 and SUPER-SCEPTRE.
51 citations
TL;DR: In this paper, a method for improving the efficiency of a slightly loaded induction motor is suggested based on the optimal-efficiency slip tracking by adjusting the voltage to frequency ratio (V/f).
Abstract: A method for improving the efficiency of a slightly loaded induction motor is suggested. It is based upon the optimal-efficiency slip tracking by adjusting the voltage to frequency ratio (V/f). It has adopted the converter-inverter fed induction motor drive system. All the control loops are implemented by the Z-80 microprocessor. By this method, 10 percent or more improvement is obtained at a quarter of the full load.
40 citations
TL;DR: In this paper, the applicability of a nontactile acoustic sensing system, which provides range information about the distance between a sensor and the workpiece, is evaluated for the three-dimensional surface characterization task.
Abstract: Robotic seam tracking systems require three-dimensional information about the seam geometry. The applicability of a nontactile acoustic sensing system, which provides range information about the distance between a sensor and the workpiece, is evaluated for the three-dimensional surface characterization task. An algorithm for executing a two-dimensional surface height sampling of an unknown workpiece is developed and evaluated through digital simulation and hardware experimentation. The algorithm incorporates the limitations of the sensor's aperture size and uses only the range information provided by the sensing system. A recovery strategy is included if the sensor's aperture has been exceeded and range information is not available. The sampling procedure is found to be applicable for piecewise constant surfaces and surfaces with slight curvature. The effectiveness of the acoustic sensing system's surface characterization can be enhanced by using a priori knowledge of the workpiece. The sensing system appears to be promising for such industrial operations as part location and inspection.
37 citations
TL;DR: A microprocessor-based incremental servo system with a variable structure implemented with an Intel 8085 microprocessor to control a dc motor, and fast response without overshoot and good steady-state accuracy can be easily obtained.
Abstract: A microprocessor-based incremental servo system with a variable structure is presented. It is implemented with an Intel 8085 microprocessor to control a dc motor, and fast response without overshoot and good steady-state accuracy can be easily obtained. The design procedure is described in detail. Also, the comparison with a conventional fixed structure system is given.
31 citations
TL;DR: In this article, the simulation of a control scheme using the principle of field orientation for the control of a voltage source inverter-fed induction motor is described, followed by an algorithm to simulate various components of the system in the digital computer.
Abstract: This paper describes the simulation of a control scheme using the principle of field orientation for the control of a voltage source inverter-fed induction motor. The control principle is explained, followed by an algorithm to simulate various components of the system in the digital computer. The dynamic response of the system for the load disturbance and set-point variations have been studied. Also, the results of the simulation showing the behavior of field coordinates for such disturbances are given.
26 citations
TL;DR: In this paper, a brushless dc motor propulsion system using synchronous motors is described which is suitable for transit applications, and the propulsion system consists of two-quadrant transistorized front-end chopper and a three-phase transistorized inverter.
Abstract: In this paper, a brushless dc motor propulsion system using synchronous motors is described which is suitable for transit applications. The propulsion system consists of two-quadrant transistorized front-end chopper and a three-phase transistorized inverter (forming the electronic commutator for the synchronous machine phase currents) to provide both controlled propulsion and regenerative braking. The control scheme makes the system operate stably at all speeds and avoids loss of synchronization. Performance characteristics of the drive are derived and compared with those of a dc motor propulsion drive. Improved low-speed performance and reduced torque pulsation are achieved by proper switching of the electronic commutators. A prototype model using a 5-hp synchronous motor is built and tested.
21 citations
TL;DR: In this paper, a method to apply the principle of integral pulse modulation to the series-resonant converter is proposed, analyzed, and tested, which facilitates combining the favorable properties of the power converter with those of the pulse integral control system (accuracy, fast response).
Abstract: A method to apply the principle of integral pulse modulation to the series-resonant converter is proposed, analyzed, and tested. The proposed control module facilitates combining the favorable properties of the series-resonant power converter (reliability, low weight, high efficiency) with those of the pulse integral control system (accuracy, fast response).
20 citations
TL;DR: In this paper, a single-phase static VAR compensator based on the current source-forced commutated inverter is analyzed, focusing on the subject of energy storage in the circuit.
Abstract: This paper analyzes a single-phase static VAR compensator, based on the current source-forced commutated inverter. Emphasis is given to the subject of energy storage in the circuit.
TL;DR: In this article, a real-time optical sensor has been integrated into a robot end effector, which consists of a four-element position sensing spot, detector and can control a robot motion in two dimensions (two translational axes or translational and rotational axes).
Abstract: A real-time optical sensor has been integrated into a robot end effector. The sensor consists of a four-element position sensing spot, detector and can control a robot motion in two dimensions (two translational axes or translational and rotational axes). Analogical detection and signal analysis ensure fast response of the sensing system. The detecting system has been connected to the ``Unimation-Puma 600'' robot, through its manual teach box, thus different tasks such as real-time path tracking, spot positioning, and teaching can be achieved. The sensor is simple in design and consequently inexpensive.
TL;DR: Three scaling techniques are applied to the design of digital controllers in such a way as to avoid overflow and to optimize the signal-to-roundoff noise ratio.
Abstract: The analysis and design of digital controllers on microprocessors using fixed-point arithmetic have been considered. Three scaling techniques are applied to the design of digital controllers in such a way as to avoid overflow and to optimize the signal-to-roundoff noise ratio. Both the scaler and the multivariable cases are treated. Statistical estimates of the steady-state roundoff and quantization errors are derived.
TL;DR: In this paper, a triangular timing wave of frequency f = 6?N?F is used where F is the reference wave frequency, and N? 1 is an integer, and a comparative analysis is presented of the PWM signal generated with this strategy with respect to a similar signal generated by means of a "traditional" triangular modulation strategy.
Abstract: A pulse-width modulation (PWM) strategy used to generate a control signal for an electronic switching inverter is described. A triangular timing wave of frequency f=6?N?F is used where F is the reference wave frequency, and N? 1 is an integer. The polarity of the timing wave is the same as the polarity of the half period of the reference wave. A comparative analysis is presented of the PWM signal generated with this strategy with respect to a similar signal generated by means of a "traditional" triangular modulation strategy.
TL;DR: In this paper, a microcomputer-based entirely digital scheme for the thyristor Leonard system is presented, which offers not only the high-performance adjustable-speed regulation of dc motors, but also other important functions and features required for the Leonard system, such as system sequencing, system triggering, various compensations for improvement in electric performances, diagnostic, monitoring and protection capabilities, drift-free characteristics, and so forth.
Abstract: The microcomputer-based entirely digital scheme for the thyristor Leonard system is presented. The main processor used is a 16-bit microprocessor. Systematic and efficient use of the microprocessor and microcomputers successfully provides the thyristor Leonard system with the entire digital scheme. This scheme offers not only the high-performance adjustable-speed regulation of dc motors, but also other important functions and features required for the Leonard system, such as system sequencing, thyristor triggering, various compensations for improvement in electric performances, diagnostic, monitoring, and protection capabilities, drift-free characteristics, and so forth. The scheme also serves smoother communications between the microcomputer-based system and a programmable host controller, which supervise a number of Leonard systems. Compact design permits the hardware construction for the digital scheme to be accommodated on a single board.
TL;DR: The main characteristics of this microprocessor implementation of two widely used industrial controllers are the general form of the equations used, the high precision maintained, and the capability of handling a wide range of numbers by means of floating point representation in the microprocessor.
Abstract: This paper discusses the microprocessor implementation of two widely used industrial controllers: the PID controller and the Lead-Lag compensator. The main characteristics of this implementation are the general form of the equations used, the high precision maintained, and the capability of handling a wide range of numbers by means of floating point representation in the microprocessor. An 8-bit general purpose microprocessor is employed, and the entire hardware and software required for the floating point arithmetic simulation and the controller's realization are presented. The flexibility of the proposed design is also discussed. The material presented in this paper may be useful to control engineers interested in microprocessor-based control, as well as to microprocessor/computer specialists interested in applications to the control field.
TL;DR: In this article, a digital proportional integral-derivative (PID) predictor controller is analyzed and its advantages relative to the normal PID controller are derived, and a design procedure which results in a robust control system is developed.
Abstract: A digital proportional integral-derivative (PID) predictor controller is analyzed, and its advantages relative to the normal PID controller are derived. A design procedure which results in a robust control system is developed. This procedure applies to both the PID predictor and the normal PID controllers. A regulator carbon dioxide control system which requires disturbance rejection is designed as an example.
TL;DR: A hybrid electric vehicle drive control system under microcomputer control where the propulsion power is shared between a gasoline engine and a dc motor is described.
Abstract: This paper describes a hybrid electric vehicle drive control system under microcomputer control where the propulsion power is shared between a gasoline engine and a dc motor. The control functions have been developed, analyzed, and implemented with highlevel language in a dual Intel 8086 microcomputer system. The drive system has been integrated and tested, and shows excellent results.
TL;DR: In this paper, the design aspects of a fiber-optic system link, suitable for industrial process applications, and addressing process environments with slowly changing parameters such as: pressure, temperature, position (both rotary and linear), available at the output of system interfacing sensors in the form of voltages, where less attention has been paid thus far.
Abstract: Industrial system considerations suggest the need for fiberoptic data links that have the ability to reduce susceptibility to noise from EMI or RFI, to isolate a system from high voltages and transmit reliable data. This paper deals with the design aspects of a fiber-optic system link, suitable for industrial process applications, and addresses process environments with slowly changing parameters such as: pressure, temperature, position (both rotary and linear), etc., available at the output of system interfacing sensors in the form of voltages, where less attention has been paid thus far. The approach used involves a voltage-pulse frequencyvoltage conversion technique with a VCO in the modulator and a PLL circuit in the demodulator. By changing a few components, the system can be converted into a simplex intercommunication optical link.
TL;DR: Overall this paper enumerates the steps involved in the design of efficient multimicroprocessor-based systems and discusses a split transaction protocol that mitigates the problem of overloading of the interconnection bus.
Abstract: In their thirteen years of existence, microprocessor chips have evolved through four generations. Contemporary 16-bit and 32-bit microprocessors offer sophisticated architectures and powerful instruction sets. However, in many industrial applications, data rates are very high and the control structure has a decentralized configuration. In either case, multiple processors must be used. The major constraint in multiprocessor systems is usually the speed of the interconnection mechanism used for communication between the computing elements. This paper covers several of these issues. First, it compares and contrasts the performance of advanced microprocessors. Second, it discusses a split transaction protocol that mitigates the problem of overloading of the interconnection bus. Third, it describes an interactive tool to model multimicroprocessor systems. Overall this paper enumerates the steps involved in the design of efficient multimicroprocessor-based systems.
TL;DR: In this article, a current-fed-type inverter suitable for induction heating and melting applications in the medium-frequency (1-5 kHz) range is presented, where the control circuitry, load power factor control, thyristor turn-off control, and protection techniques are discussed.
Abstract: This paper is concerned with the development of a current-fed-type inverter suitable for induction heating and melting applications in the medium-frequency (1-5 kHz) range. The control circuitry, load power factor control, thyristor turn-off control, and protection techniques are discussed. A simple and reliable starting scheme has been developed which provides reliable start-up with all practical loads. The starting circuit has a main and an auxilliary part. The necessity of one or both of these starting circuits is discussed. Experimental results from a prototype unit are presented. The performance of the equipment has been found quite satisfactory.
TL;DR: The proposed grapho-analytical procedure, applicable to third-order digital control systems, enables the designer to readily obtain the information about effects of system constants and adjusting system parameters on the accuracy, speed of response, and stability margin.
Abstract: This paper presents the pole-placement method for the synthesis of the dc motor speed control system. The proposed grapho-analytical procedure, applicable to third-order digital control systems, enables the designer to readily obtain the information about effects of system constants and adjusting system parameters on the accuracy, speed of response, and stability margin. The design of the real motor speed control system is presented to illustrate the proposed technique.
TL;DR: In this article, a speed controller with proportional-integral (PI)-plus bang-bang action is proposed for dc servomotors with transistorized pulse width modulated (PWM) drives.
Abstract: A speed controller with proportional-integral (PI)-plus bang-bang action is proposed for dc servomotors with transistorized pulse width modulated (PWM) drives. The controller employs the PI-action when the magnitude of the error between the reference signal and the speed output signal is smaller than some precribed value. Otherwise, the controller produces the maximum allowable control signal with the integrator reset. Specifically, a mathematical analysis of the motor system with the proposed speed controller is presented and a rule of thumb for parameter design is provided.
TL;DR: In this paper, a novel pulsewidth modulation (PWM) strategy was developed for application in uninterruptible power supply (UPS) and ac motor drive systems. And the voltage/current harmonic spectra and other properties of this PWM scheme were thoroughly investigated.
Abstract: This paper develops a novel pulse-width modulation (PWM) strategy for application in uninterruptible power supply (UPS) and ac motor drive systems. The voltage/current harmonic spectra and other properties of this PWM scheme are thoroughly investigated. This modulation strategy is compared with other modulation techniques, especially with the commonly used sinusoidal modulation scheme, from the standpoints of simplicity, inverter switching losses, motor losses, and other output performance features. This novel modulation scheme produces an acceptable motor curent waveform while keeping the number of inverter commutations low. Implementation of this scheme is quite simple in hardware-based as well as microprocessor-based systems.
TL;DR: In this article, a sufficient condition for the absence of limit cycles, based on the Vidal-Wegrazin (VW) criterion, is developed, and it is shown that noise, acting as dither, actually improves performance by quenching limit cycles.
Abstract: This paper addresses some of the issues concerning limit cycles due to fixed-point implementation of control algorithms. It is shown that a dc equilibrium point may not always exist, although its existence is easily guaranteed for Type-1 systems. Simple formulas are given for bounds on the amplitude (rms and absolute) of limit cycles, should they occur. These bounds can be decreased by increasing word length. A sufficient condition for the absence of limit cycles, based on the Vidal-Wegrazin (VW) criterion, is developed. Finally, it is shown that noise, acting as dither, actually improves performance by quenching limit cycles.
TL;DR: A multiprocessor system consisting of three processors built for reliable control of an electrically powered leg (the OSU Monopod) is described.
Abstract: A multiprocessor system consisting of three processors built for reliable control of an electrically powered leg (the OSU Monopod) is described. All computations are done in a redundant fashion by two processors. Results are then compared by a different pair of processors, and all three processors participate in the identification of the faulty processor in case of a disagreement of the two sets of results. The system is reconfigured when one of the computers fails. Comparison and fault diagnosis are done by software.
TL;DR: This paper shows that the power loss in a thyristor and its commutation circuit can be adequately calculated from a detailed knowledge of the current waveforms and the use of a simple model for conducting thyristors and diodes.
Abstract: This paper shows that the power loss in a thyristor and its commutation circuit can be adequately calculated from a detailed knowledge of the current waveforms and the use of a simple model for conducting thyristors and diodes. In some thyristor circuits, device switching losses can be neglected with little loss in accuracy. Snubber losses are included. The analytical technique described is verified.
TL;DR: In this article, the effects of quantization and bounds on limit cycles in digital closed-loop systems were investigated by examining a typical proportional plus integral type of controller found in process control.
Abstract: The practical and reliable application of direct digital control in industrial systems is a long way from the study of sampling control in modern control literature. Numerous mechanical failures of hydraulic tubes, seals, and mechanical connections have demonstrated that these systems are easily fatigued by ``jitter'' or the type of noise that can arise in digital systems due to quantization of signals. Yet the transition from analog to microprocessor-based control implies a sampled control with inherent noise due to finite word length and finite sampling period. Even if the sampling frequency does not cause instability, it can fatigue the system with limit cycles. This paper investigates the effects of quantization and establishes bounds on limit cycles in digital closed-loop systems by examining a typical proportional plus integral type of controller found in process control. The work is based on the technique used by Long and Trick [1] to establish bounds on limit cycles in digital filters.
TL;DR: A method for the design of controllers for closed-loop converter-controlled dc drives is given and Popov's stability criterion has been applied for analyzing stability in the large of the drive system.
Abstract: A method for the design of controllers for closed-loop converter-controlled dc drives is given. Popov's stability criterion has been applied for analyzing stability in the large of the drive system. The paper includes experimental and digital simulation results of a dc drive.
TL;DR: A dual-rate sampling self-tuning regulator that overcomes this problem by allowing a data sampling rate to be chosen consistent with the system time constants and a control output interval based on the computation time is described in this paper.
Abstract: Standard single-rate sampling self-tuning regulators may not be able to effectively control fast-acting systems if the minimum computation time required is larger than the largest sampling period permissible. A dual-rate sampling self-tuning regulator that overcomes this problem by allowing a data sampling rate to be chosen consistent with the system time constants and a control output interval based on the computation time is described in this paper. This algorithm is also very suitable for implementation using fixed word-length processors as the quantization problems are minimized. The algorithm has been implemented on a microprocessor. Implementation details with emphasis on data acquisition, interrupt controlled sampling, time sufficiency test and scaling, and experimental results are also given.