Muhammad Nizam Kamarudin

Simulink implementation of digital cascade control DC motor model - a didactic approach

This paper depicts the interactive and easiest method of developing a digital cascade control model for direct current (DC) motor in SIMULINK environment. The development method is described step-by-step to give better understanding to electrical engineering students. The development phase focuses on the dasiahands onpsila approach so that students and engineers able to follow the steps. SIMULINK/MATLABcopy is used based on its reputation as a powerful tool for engineers and scientists when developing and modeling systems. Modeling phase begin with the model of a simple DC motor, a DC/DC H-bridge converter and controller design. Various control method shown in this paper provides interactive learning on how to perform conventional proportional - integral (PI) controller and intelligent self tuning PI controller using fuzzy algorithm. In the DC/DC H-bridge converter design, the significant used of a particular power electronic devices is thoroughly elaborated.

Control of uncertain nonlinear systems using mixed nonlinear damping function and backstepping techniques

This paper depicts the design of control law to stabilize nonlinear system with mixed match-mismatch uncertainties with bounded disturbance. The design approach exploit the advantages and flexibility of backstepping technique. To compensate for the uncertainties and bounded disturbance, nonlinear damping function is augmented to the pre-designed unperturbed stabilizing function. Throughout the design, Youngs inequality and comparing squares method is used to avoid elimination of useful nonlinear terms as well as to obtain feasible control law.

Variable Speed Wind Turbine with External Stiffness and Rotor Deviation Observer

Often in prominent literature, the appearance of external stiffness in wind turbine dynamical model has been neglected. The ignorance of external stiffness eliminates the presence of rotor-side angular deviation in the system dynamic. In order to give more practical look of the variable speed control system structure, we develop a linear observer to estimate the rotor angular deviation. We use Linear Quadratic Regulator (LQR) to design the observer gain, as well as the estimation error gain. To facilitate observer design, the system is linearized around its origin by using Jacobian matrix. By using the estimated rotor angular deviation, we design a variable speed control via Lyapunov and Arstein to enhance power output from the turbine.

Robust Control Design of Nonlinear System via Backstepping-PSO with Sliding Mode Techniques

This research focus on designing controller for nonlinear system by integration of two robust controllers, back-stepping and sliding mode controller. The dynamics of the system is developed by consider its nonlinearities incorporating external disturbance injected to the system’s actuator. The value of control and reaching law parameters are determined by using particle swarm optimization method such that these parameters are varying automatically according to the changes of the dynamics of the system. The tracking performance of the system yielded by integration of back-stepping and sliding mode controller is compared with its output performance produced by classical sliding mode controller. The results show that assimilation of back-stepping and sliding mode controller for the chosen system generates better performance than sliding mode controller itself which is evaluated in terms of tracking output and tracking error.

Controller design for position tracking of nonlinear system

Usually, the nonlinearities existing in the system is eliminated by using linearization method. However, backstepping method allows additional nonlinearities to be created and introduced to the control process so that the undesirable nonlinearities can be cancelled out from the system. In this work,position tracking of electrohydraulic actuator system is taken as a numerical example since it is highly nonlinear. Backstepping controller is designed for the system without disturbance and with additional disturbance is given to its actuator. Control parameter of the designed controller for both condition is then optimized by using Particle Swarm Optimization method. The performance of the designed controller to the system is observed through its tracking error.

Achieving Thermal Power System Stability Using Load Frequency Controller

This paper focuses on load frequency control (LFC) of a single area thermal power system. The purpose of LFC is to minimize the transient varieties due to frequency deviation by ensuring zero steady state error. The frequency deviation normally caused by load perturbation. Hence, the primary goal of this paper is to design LFC for power system stability. Single area thermal power system comprises of governor framework, non-reheat turbine model and generator with load. The closed loop system performances in term of transient and steady state are observed and analyzed by injecting multifarious load perturbation. The simulation results are obtained via simulation works using MATLAB with SIMULINK toolbox.

Achieving optimum tip-speed-ratio of a two-mass wind turbine system

This paper proposes a three term PID controller to achieve optimum tip-speed ratio of a variable speed fixed pitch two-mass wind turbine system. The main advantage of the method is the functional simplicity and the robust performance in a wide range of operating condition. The objective is achieved by maintaining optimum speed of the rotor via adjusting the restoring generator torque. Hence, PID controller is formulated and employed into the generator side of wind turbine system to achieve the asymptotic tracking of the rotor speed. To validate the effectiveness of the proposed method, a simulation in MATLAB/SIMULINK® is carried out. The result shows that the speed tracking can be achieved by using PID. However, the speed response shows inadequate control performance with less efficacy as the closed-loop system incur large initial speed overshoot. This phenomena shows the shortcomings of conventional PID and hence, open up new research awareness on solving this problem.

PV generation and its impact on low voltage network

The objective of the paper is to present the modelling of the single phase grid connected Photovoltaic (PV) generation and its impact on low voltage grid. The network model has been developed in PSCAD software. The designed system includes low voltage network, single phase voltage source inverter (VSI) to control active (P) and reactive power (Q) flow to the grid and PV panel as the main source of energy. In order to control PV active power output and maintain the reactive power to zero value, a typical control scheme (PQ control) has been used. The impact of the PV generation on the network voltage is assessed and analyzed.

Analysis of integrated sensors for unmanned underwater vehicle application

This paper presents an integrated sensor system to be applied in underwater vehicles based on 5-DOF Inertial Measurement Unit (IMU) sensor, MPX pressure sensor, and temperature sensor. The main idea of the research is to improve the performance of the integrated sensor system by using the MATLAB Simulink connected to MicroBox 2000/2000C for underwater vehicles applications. An integrated sensor or known as the smart sensor is a small component that designed to gather important data. These types of sensors combined or integrated with signal processing hardware in a single compact device. All sensors are placed in a hard casing made of steel with the dimensions of 0.10 m diameter, 0.85 m height and weight of 0.23 kg. The output of the sensors shows that; the offset error of accelerometer and gyroscopes are within 0.5 to 1.0 and 0.1 to 0.5 respectively. It is shown that the pressure occurs at 0.75s and the reading in volt increased rapidly until 0.5V and maintained at 0.5V for 1 s. With minimum implementation cost and improved performances of the integrated sensor, this research benefits offshore and underwater industries.

Nonlinear stabilization with bounded controller

This In this paper, an extension of the Sontags universal formula is proposed. For benchmark, the proposed method is compared with two other approaches, i.e. a universal Sontags formula and a direct Lyapunov with comparing square. To observe the efficacy of the proposed method, a numerical nonlinear system with cubic damping is stabilized. The effectiveness of the proposed method is shown that the magnitude of the control signal can be bounded without a catastrophic effect to the closed loop stability. Other appealing features of the proposed method is that the stabilization cost can be reduced, and the elimination of the useful nonlinear terms can be avoided.