DSpaceCRIS@UNITENhttp://dspace.uniten.edu.my/jspuiThe DSpace digital repository system captures, stores, indexes, preserves, and distributes digital research material.Sun, 19 Jan 2020 19:13:17 GMT2020-01-19T19:13:17Z5041- Model predictive control for current balancing in a four-phase buck converterhttp://dspace.uniten.edu.my/jspui/handle/123456789/5927Title: Model predictive control for current balancing in a four-phase buck converter
Authors: Yahaya, J.A.F.; Mansor, M.
Abstract: Multiphase buck topology offers smaller ripple current and lower component ratings. This, however, compromises unbalanced output current between each phase of an inductor which leads to over-current and inductor saturation issues. Often when discussing the linear control schemes, it involves the use of superposition theorem to understand the system's response. However, the limitation of superposition theorem in this application is that it assumes the circuit to be completely linear. For components with nonlinear behaviour such as power switches and diodes, the analytical results may not be accurate resulting to unexpected behaviour as the algorithm is implemented on a real system. Hence, the use of a more advanced control scheme is necessary to improve a system with a non-linear characteristic. This paper proposes a current limit control (CLC) consists of MPC for inner loop control and PID for outer loop control for phase current balancing in a four-phase buck converter. The controller is designed to achieve balanced current for each phase with acceptable response time. The proposed system is designed using MATLAB/Simulink simulation software and verified by a laboratory prototype with a TMS320F28335 as the main controller. Simulation and experimental results are provided to validate the system performance.
Fri, 01 Jan 2016 00:00:00 GMThttp://dspace.uniten.edu.my/jspui/handle/123456789/59272016-01-01T00:00:00Z
- Current control scheme for unbalanced current distribution in a four-phase converterhttp://dspace.uniten.edu.my/jspui/handle/123456789/10499Title: Current control scheme for unbalanced current distribution in a four-phase converter
Authors: Yahaya, J.A.F.; Mansor, M.
Abstract: A multiphase DC-DC topology is mostly used for high current application in electric vehicles (EV), CPU processing circuit, communication systems and etc. Although this topology has an advantage of lower manufacturing costs and smaller in size. This topology, however, is susceptive to the unbalanced phase current issue which can cause malfunction to the converter. Due to this, a dual-loop control is usually used in a DC-DC multiphase converter. The outer-loop is responsible for the output reference and inner-loop handles the current balancing between each phase inductors. Conventional linear control schemes can only function within certain bandwidth and are easily affected by disturbances. This paper proposes a combination of current control scheme where the outer loop is controlled by linear controller and model predictive control (MPC) controlling the inner current loop to overcome those drawbacks. The objective of the experiment is to ensure equal current distribution between each phase when subjected to disturbances in the input source and step load changes. For comparison purposes, a pure linear compensator and the proposed method will be used in the closed-loop system. The controllers are designed using MATLAB/Simulink. © 2017 IEEE.
Mon, 01 Jan 2018 00:00:00 GMThttp://dspace.uniten.edu.my/jspui/handle/123456789/104992018-01-01T00:00:00Z
- Arc flash assessment on photovoltaic grid connected systemhttp://dspace.uniten.edu.my/jspui/handle/123456789/10498Title: Arc flash assessment on photovoltaic grid connected system
Authors: Yahaya, J.A.F.; Mansor, M.
Abstract: This paper presents a comparative study of two different output capacities for a photovoltaic (PV) grid-connected system employing arc flash assessment. Implementation of renewable energy (RE) sources into the grid generally requires load flow and short circuit analysis to study the contribution of RE system into the grid. However, the study involving arc flash assessment is not well known and therefore not mandatory in some countries for new installation of RE system. Arc flash assessment covers the safety aspect in terms of arcing current due to a fault at any location in a network. Therefore, a comparative study for both 17kW and 255kW PV system is conducted using arc flash assessment to evaluate the hazard level between the two and analyzing the correlation of arcing current intensity and personal protective equipment (PPE) used to minimize the hazard. Both of the PV networks are designed and simulated using electrical power system or ETAP. © 2017 IEEE.
Mon, 01 Jan 2018 00:00:00 GMThttp://dspace.uniten.edu.my/jspui/handle/123456789/104982018-01-01T00:00:00Z
- Experimental implementation controlled SPWM inverter based harmony search algorithmhttp://dspace.uniten.edu.my/jspui/handle/123456789/5926Title: Experimental implementation controlled SPWM inverter based harmony search algorithm
Authors: Najeeb, M.; Mansor, M.; Razali, R.; Daniyal, H.; Yahaya, J.A.F.
Abstract: An optimum PI controller using harmony search optimization algorithm (HS) is utilized in this research for the single-phase bipolar SPWM inverter. The aim of this algorithm is to avoid the conventional trial and error procedure which is usually applied in finding the PI coefficients in order to obtain the desired performance. Then, the control algorithm of the inverter prototype is experimentally implemented using the eZdsp F28355 board along with the bipolar sinusoidal pulse width modulation (SPWM) to control the output voltage drop under different load conditions. The proposed overall inverter design and the control algorithm are modelled using MATLAB environment (Simulink/m-file Code). The mean absolute error (MAE) formula is used as an objective function with the HS algorithm in finding the adaptive values of kp and ki parameters to minimize the error of the inverter output voltage. Based on the output results, the proposed voltage controller using HS algorithm based PI (HS-PI) showed that the inverter output performance is improved in terms of voltage amplitude, robustness, and convergence rate speed as compared to PSO algorithm based PI (PSO-PI). This is to say that the proposed controller provides a good dynamic responses in both cases; transient and steady-state. Finally, the experimental setup result of the inverter controller is verified to validate the simulation results.
Sun, 01 Jan 2017 00:00:00 GMThttp://dspace.uniten.edu.my/jspui/handle/123456789/59262017-01-01T00:00:00Z