Open-loop controller

About: Open-loop controller is a research topic. Over the lifetime, 16148 publications have been published within this topic receiving 224014 citations. The topic is also known as: non-feedback controller & open-loop control law.

Controller and control method for a pool system

Abstract: A controller and method for controlling the operation of electrically powered pool related apparatus in recreational pool system, and more particularly for controlling the flow of pool water through the pool system and water-conditioning apparatus, is disclosed. The controller includes a logic circuit formed with a plurality of logic gates coupled to pool-water-sensing apparatus and programmable input apparatus in accordance with a predetermined logic sequence. The pool system includes a swimming pool and spa, and the pool-water-conditioning apparatus includes a solar water heater and a non-solar water heater. The controller is capable of preferential solar heating and of temperature-switched operation, time-switched operation and a combination thereof, as well as manual switching.

Simultaneous online automatic tuning of cascade control for open loop stable processes

Abstract: In this paper, we present a new simultaneous online automatic tuning method for cascade control using a relay feedback approach. Departing from the traditional approach towards tuning of cascade control systems where the secondary and primary loops are tuned in strict sequence, the proposed approach is to carry out the entire tuning process in one experiment. For ease of practical applications, the entire procedure of controller design may be automated and carried out online. A direct controller tuning approach to tune the controllers is proposed here. Robustness analysis of the new cascade control design is further carried out in the paper by drawing on existing results for SISO feedback systems. Simulations are provided to illustrate the applicability and effectiveness of both the online autotuning approach and the new cascade control design.

Adjustable gain controller for valve position control loop and method for reducing jitter

Abstract: An adjustable gain controller for a steam turbine valve position control loop includes an electronic operator, a proportional controller, a derivative controller and an integral controller A steam flow condition error signal is amplified by the reciprocal of the valve's regulation value The amplified error signal is supplied to the electronic operator and to the integral controller The electronic operator includes means for initially selecting a value of A and n and generating a gain factor from a nonlinear gain characteristic function utilizing those values in combination with the valve's regulation value and the normalized error signal The electronic operator multiplies the amplified error signal by the gain factor and applies the resultant signal to the proportional controller and the derivative controller The output signals from the proportional, derivative and integral controllers are summed together and that sum is input into an electrohydraulic valve actuator system The electrohydraulic valve actuator directly positions the steam valve Hydraulic and mechanical jitter is reduced by adjusting the values of A and n to reduce the jitter in the electrohydraulic valve actuator system

Optimal gain tuning of PI speed controller in induction motor drives using particle swarm optimization

Abstract: This article presents particle swarm optimization (PSO)-based optimal gain tuning of proportional integral (PI) speed controller in an induction motor (IM) drive (30 hp) with mine hoist load diagram. Optimization considers the load and speed variations, and provides appropriate gains to the speed controller to obtain good dynamic performance of the motor. IM performance is checked with the optimal gains through the simulation studies in MATLAB/SIMULINK environment. Results are compared with hand tuning (fixed gains) and fuzzy logic (FL) speed controller. Hybrid of FL and PSO-based PI controller for the speed control of given motor is also performed to eliminate the drawbacks of PI controller (overshoot and undershoot) and FL controller (steady-state error). From the simulation studies, hybrid controller produces better performance in terms of rise time, overshoot and settling time.