Performance Study of PID Controller and LQR Technique for Inverted Pendulum

This paper presents the position tracking performance of an electro-hydraulic hydraulic actuator (EHA) system by using a discrete sliding mode control (DSMC). A point-to-point trajectory is used in the experimental works to evaluate the performance of the DSMC which is design in two-degree-of-freedom (2-DOF) control structure. The design consists of DSMC and a feed forward controller. The control law is derived from the reaching law concept and its parameters are determined methodically based on the identified model. Experimental results reveal that the DMSC with 2-DOF control structure is highly robust and capable to deal with the uncertainties and disturbances occur during the position tracking control for different point of trajectories. It is also shows that the proposed controller can achieve better tracking performance as compared to conventional LQR and PID controller.

In this study, a nonlinear Archimedes wave swing (AWS) energy conversion system was employed to enable the use of irregular sea waves to provide useful electricity. Instead of the conventional PI controllers used in prior research, this study employed fractional-order PID (FOPID) controllers to control the back-to-back configuration of AWS. The aim was to maximize the energy yield from waves and maintain the grid voltage and the capacitor DC link voltage at predetermined values. In this study, six FOPID controllers were used to accomplish the control goals, leading to an array of thirty parameters required to be fine-tuned. In this regard, a hybrid jellyfish search optimizer and particle swarm optimization (HJSPSO) algorithm was adopted to select the optimal control gains. Verification of the performance of the proposed FOPID control system was achieved by comparing the system results to two conventional PID controllers and one FOPID controller. The conventional PID controllers were tuned using a recently presented metaheuristic algorithm called the Coot optimization algorithm (COOT) and the classical particle swarm optimization algorithm (PSO). Moreover, the FOPID was also tuned using the well-known genetic algorithm (GA). The system investigated in this study was subjected to various unsymmetrical and symmetrical fault disturbances. When compared with the standard COOT-PID, PSO-PID, and GA-FOPID controllers, the HJSPSO-FOPID results show a significant improvement in terms of performance and preserving control goals during system instability

The aim of this paper is to propose a neural network based reference modified PID control which has a simple duration design method for transient characteristics improvement of digitally controlled dc-dc converters. In renewable energy network systems, various types of dc-dc converters are widely used for power conversion and such converters require a superior control method for a stable operation. Especially, transient characteristics should be improved since they heavily affect the stability of the system. For such purposes, designing of conventional control methods becomes a difficult task since the optimization of control parameters needs complicated analysis and it is affected from variations of circuit components of converters. Therefore, simple and easy design of control is widely required for a stable operation of power converters. The neural network can provide a suitable control methodology for such situation since it treats the plant as a black box and it can realize a non-linear control based on training of the input-output relation without complicated modelling and analysis. On the other hand, the neural network based method has a disadvantage caused from the fact that the neural network is trained with data obtained in advance and an overcompensation phenomenon occurs in the transient response. In this paper, the neural network control is adopted to control the dc-dc converter in coordination with a conventional PID control. The neural network predicts the output voltage of the converter and the reference value in the PID control is modified with the predictions to reduce the error of the output voltage. To avoid overcompensation, a simple duration design for the neural network control is also provided to improve the transient response effectively. From prototype testing in simulation and experiment, it is revealed that the proposed method contributes to obtain a superior transient performance compared with the conventional PID control.

Through LFC tie-line interchange power of the area within prescribed limit and scheduled frequency of the system can maintain constant. Generally, Integral (conventional) Controllers are used in Load Frequency Controllers but they are quite slow. In this paper, we have used the PID controller for two-area power system in place of conventional controller and by using various adaption techniques we are tuning controllers. In order to verify the performance of PID and conventional controller, comparative results of both controllers are also presented. Overshoot and settling time are better with PID controller. The result demonstrates the effectiveness of PID controller over conventional controller. Different techniques like Ziegler Nichols and Nonlinear Control Design technique are used for comparing the responses of conventional controllers with PID controllers.

The traditional manual operation mode has problems such as high manpower cost, low efficiency, low safety, low operating precision, etc. Achieving unmanned intelligent systems in the field of mechanical and electrical engineering has become the key to transforming and upgrading relevant enterprises and improving their overall competitiveness. In this paper, an improved fuzzy PID control system is constructed based on a PLC control system combined with a fuzzy PID intelligence algorithm. It is applied to the pumping motor, coagulation dosing system, and other specific devices for simulation experiments, compared to the conventional PID algorithm, and evaluated the control system in this paper. The fuzzy PID control algorithm of this paper reduces the steady-state adjustment time of the response curve by 30% compared to the conventional PID algorithm, and the overshooting amount is reduced by 25%. With almost no overshoot, the pumping motor that was equipped with this paper’s PID algorithm reached its stable target speed in 0.3 seconds. In addition, this study found that in the coagulation dosing system model incorporating the fuzzy PID algorithm of this paper, when the model is accurate, only 20% of the overshooting amount occurs after the system has been running for some time. The conventional PID algorithm’s 50% overshoot is significantly less than this, and the time it takes to reach a steady state is also 50 minutes earlier than the conventional PID control. When the model is imprecise, fluctuations occur in both conventional PID control and fuzzy PID control, but the amplitude of the fluctuations in fuzzy PID control is relatively small. In conclusion, this paper shows that the fuzzy PID control algorithm in this paper has higher control accuracy, response speed, and stability than the conventional PID control algorithm.

This work proposes an algorithm based on Fuzzy Logic technique for the AGC of a power system controller to enhance the performance of the conventional controller during normal and abnormal condition (variation of load). The dynamic responses of Iraqi super grid network (400 kV) under normal and 10% step load increase (as a severe condition) to investigate using the fuzzy logic -PID controller and a conventional PID controller in MATLAB/SIMULINK environment. The obtained results show the proposal intelligent controller and have improved the dynamic response of the Iraqi grid, and at the same time, It is faster than the conventional PID controller in terms of reducing settling time, overshoot and oscillations.

In this paper existing sliding mode control for nonlinear dynamic systems is demonstrated and its performance is evaluated against conventional PID controller . The changes in system dynamics occurs due to parametric uncertainties and external disturbances. Here it is shown that the sliding mode control based on the variable structure control is a robust control technique against parametric uncertainties and external disturbances. The effect of chattering in SMC is reduced using a boundary layer approach. The PID controller being a fixed structure control system is sensitive to parametric uncertainties and external disturbances. The sliding mode control and PID controller are illustrated in computer simulation for modeled spring-mass dashpot system and coupled tank system. Finally the performances of SMC are compared with conventional PID controller for the above systems to show the dominance of SMC over conventional PID controller.

Grinding-classification process is key links in beneficiation production; the mill load control due to the presence of large inertia lag problem, so rely on the conventional PID control is difficult to achieve the expected control effect. Based on the conventional PID control, combined the Fuzzy control and the Smith predictive control, putting forward a kind of Fuzzy+Smith+PID control method. Through MATLAB simulation study shows that, compared with the conventional PID control, the new control method has the advantages of short regulating time, small overshoot, high control precision and no steady state error.

Nonlinear PID (N-PID) Controller for SSSP Grid Connected Inverter Control of Photovoltaic Systems

A simplified Fuzzy-PID controller is designed for 2-axes antenna stabilization and tracking system. Next, the performance of the controller is further verified by computer simulations with Matlab, a 2-Axes antenna, and a small unmanned test helicopter. With the advantages of embedded controller and simplified fuzzy control theory, high performance techniques for antenna tracking control are designed. A comparison between the performance of the conventional PID controller and the Fuzzy-PID controller, which is designed by the same PID control gains, is made as a way to verify the performance of the designed antenna servo control system. The proposed Fuzzy-PID controller has better superior performance than the conventional PID controller with respect to all cases of simulations and experiments.

The fuzzy PID controller is proposed to improve the performance of the network pressure-superposed water supply (NPSWS) system. Taking the pump as the load of the asynchronous motor, the whole system can be simplified as a second-order model. On the basis of the model, fuzzy rules are designed to complete on-line parameters adjustments of PID controller. Comparisons are made between the fuzzy PID controller and the conventional PID controller in terms of dynamic performance, steady state performance and noise immunity. The simulation results show that the fuzzy PID controller not only has faster response, slighter overshoot, stronger noise immunity, but also has wider adaptation range and higher accuracy in stability than PID controller.

Currently, the production of the rapid increasing electrical energy in Kuwait depends mainly on oil and its derivatives, which result in environmental pollution. Moreover, the export of oil production represents a key income for Kuwait and any saving in its consumption represents an essential concern to land’s economy. Therefore, the power utility and economy of Kuwait will benefit from substituting fossil fuels by clean and renewable energy resources such as solar energy. For efficient utilization of solar energy, the PV panel should track the maximum power point (MPP) under various weather conditions in Kuwait. Most of existing MPP tracking techniques depend mainly on perturb & observe (P&O) or incremental conductance (IC) algorithm using conventional PID controllers. On the other side, fuzzy logic controller (FLC) provides an adaptive nature, fast response, good performance and ability to handle non-linear characteristics. In this paper, the proposed (FLC) substitutes PID controller in P&O and IC (MPPT) under different weather conditions in Kuwait. The obtained results of the proposed (FLC) are compared with conventional PID controller. The performance of the implemented PV panel is validated and the results indicated that FLC has successfully tracked the MPP with minimum voltage oscillations.

Although the traditional PID controller is widely used in many fields, the system parameters varying and external disturbances existing in the DC servo system will cause large overshoot or poor stability. To improve the performance of the PID controller, a compound servo control system combining the conventional PID control and the fuzzy control is presented to meet the demand of a vehicular antenna servo system in this paper. Incorporating the fuzzy control and the conventional PID control, this paper presents a design method of the fuzzy PID controller that is based on the fuzzy tuning rules and formed by integrating two above control ideas. Simulation results are presented to show the efficiency of the proposed controller. The practical control effect shows that the control system that adopts the fuzzy PID controller has better performance than that of the traditional PID control system, and meets the performance requirements of the servo system.

This paper presents a new design perception for slave controller in Cascade process control System. It ensures enhanced robustness by minimizing the physical presence of slave controller in the cascaded loops. The desired outputs are trained by ANN using BPN. A Level and flow measurement system is taken as an experimental set up. The level controller is the master controller and the flow is the slave controller in a conventional PID controller. Using ANN, we minimize the presence of the flow controller. ANN with three inputs and one output with single hidden layer with five hidden neurons are used as a slave controller. The training set attained from the knowledge of the conventional PID controller is used to train the network. The performance of the process is evaluated MSE criterion. The output response of the cascade process control system using suggested control methods is compared with the traditional PID controller. Error versus epoch analysis gives us a clear picture of convergence of output nearer to the real time values attained from the conventional PID controller. The control results clearly state that this soft slave controller shows better performance than the physical slave controller.

This paper presents a design of robust PID controller structure for shunt FACTS controllers namely STATCOM and SVC. Robust STATCOM and SVC is designed using H-infinity loop-shaping technique. The performance of the controller is tested in single machine infinite bus power system to damp out the oscillations. The variation of transmission line reactances is considered as multiplicative uncertainty and the design is carried out by applying robustness criteria to improve both stability and performance. The performance of robust controller is compared with conventional PID controller in damping out the oscillations. It has been observed that the conventional PID controller is ineffective at operating points other than nominal. The robust design provides an extremely good damping characteristic over a range of operating conditions and it is evaluated based on the time domain specifications