Showing papers on "Proportional control published in 1974"
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TL;DR: In this article, the authors describe the design, construction, and testing of a speed control unit for a separately excited dc motor fed from a three-phase six-pulse fully controlled thyristor bridge.
Abstract: This paper describes the design, construction, and testing of a thyristorized speed control unit for a separately excited dc motor. The motor is fed from a three-phase six-pulse fully controlled thyristor bridge. A speed loop with a proportional plus integral controller maintains the desired speed irrespective of the load variations on the motor. An inner current control loop protects the thyristors from overcurrents. This loop also provides fast response overcoming the effect of disturbances such as variations in supply voltage. The design aspects of the control loops are discussed, and experimental results are given.
64 citations
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05 Mar 1974
TL;DR: In this article, a proportional plus integral controller connectable in a conventional proportional control loop of a process control system is selectively operable in either a proportional only mode or a proportional+integral mode in accordance with the positioning of a mode select switch.
Abstract: A proportional plus integral controller connectable in a conventional proportional control loop of a process control system is selectively operable in a proportional only mode or a proportional plus integral mode in accordance with the positioning of a mode select switch and exhibits substantially bumpless forward transfer from proportional only to proportional plus integral operating modes.
20 citations
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01 Jul 1974TL;DR: In this paper, a head controlled mechanism for the proportional control of a driven devi was proposed, whereby a control signal is generated proportional to the movement of the head of an operator to control the speed and direction of the driven device.
Abstract: A head controlled mechanism for the proportional control of a driven devi A mechanism is provided whereby a control signal is generated proportional to the movement of the head of an operator to control the speed and direction of the driven device
16 citations
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8 citations
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TL;DR: In this paper, a fast time positional control system of third order has been proposed, where a first bang-bang mode operates until the position is close to target, followed by a second linear feedback mode which gives asymptotic stability.
Abstract: A design is reported for a fast time positional control system of third order which has two modes of operation; a first bang-bang mode operates until the position is close to target, followed by a second linear feedback mode which gives asymptotic stability. The design is applicable to situations in which the positional state is to be moved repeatedly among a finite set of target positions. The switch times for the first mode are selected to minimize the time to reach the mode boundary plus a terminal penalty which is the settling time of the second mode. In the example given, the response time using this controller is compared with the optimal time to the target, and with the response time of equivalent saturating proportional control.
2 citations
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03 Sep 1974
TL;DR: In this paper, a summing amplifier with a pseudo summing junction in a feedback network is presented, where the output of the system is biased by a DC voltage while simultaneously applying a second voltage to a conventional summer junction.
Abstract: A summing amplifier system having a pseudo summing junction in a feedback network for biasing the output of the system by a DC voltage while simultaneously applying a second voltage to a conventional summing junction of the system. As a process variable controller, the system provides proportional control, the said second voltage representing deviation of the process variable, and manual reset, the said DC voltage representing a manual reset voltage.