Measurement, Control, and Automation

Research on a solution to eliminating position noise in a Slotless Self-Bearing Motor control system

2023-03-13T19:02:47+07:00

The content of this paper presents a solution to avoid noise for the SSBM motor control system. First, this paper analyzes the theoretical basis of situations where noise can affect motor operation. Then, the authors developed a method of direct current supply to maintain lift and the current transformation from the axis (X, Y) to the axis (ad, be, and cf) to eliminate the phenomenon of reverse braking torque. In addition, the authors also added a noise-compensating feed-forward control in the position control system. To demonstrate this solution, the SSBM motor control system was built on Matlab/Simulink. Simulation results have shown the ability to eliminate position noise, which helps the Slotless Self-Bearing Motor system to operate more stably.

Adaptive sliding mode control for a secure communication system

2023-03-30T08:38:10+07:00

This paper discusses the design of a sliding controller for secure communication of electronic circuits based on a master and slave chaos system. Firstly, we present a 3D model of the chaotic system. Secondly, the mathematical models of the master and slave systems was remodeled into the Takagi-Sugeno fuzzy system (T-S). Thirdly, an adaptive sliding control for synchronization of master and slave systems. Fourthly, the stability of the control method was proved by using Lyapunov. Fifth, the MATLAB simulation was used to confirm the correction and effectiveness of the control method. The synchronization process of chaotic systems is successfully tested through experiments by using the electronic circuit communication. The states of slave system are precisely tracked states of the master system.

Adaptive dynamic surface control design for soft-link multi-motor drives

2023-04-18T21:57:18+07:00

A multi-motor is known as a mechanism in which separate motors are used for operating different parts of the same machine in industrial plants. The complex operation of systems, such as steel mills, casting irons, paper production, solar cells, humanoid robots, large excavators, etc., depends on the performance of the multi-motor drive system. These materials are easily damaged if the process is poor. Therefore, the system requires high technology in mechanics and precise control techniques. In addition, because the system has many variable parameters, strong nonlinearity, and is affected by many external noises, there are many challenges in the design process. This paper proposes a sustainable control method that integrates the DSC algorithm combining an adaptive compensation algorithm using an RBF neural network, which makes the tension and velocity of the batches approximate to the set value, and helps the system to be stable with variable parameters. The stability of the system is guaranteed and the effectiveness of of the proposed control approach is verified via simulations.

Predictive Direct Power Control of Grid-Connected PV Systems

2023-04-04T21:30:49+07:00

This paper presents an effective grid-injected power control method for photovoltaic (PV) systems based on the theory of model predictive control (MPC). Future values of the grid-injected active and reactive power can be predicted by using the discrete-time model of a grid-connected two-level voltage-source three-phase inverter. The grid-injected active and reactive power can be conveniently controlled by minimising a defined cost function of active and reactive power reference for optimally selecting the switching states of the inverter. The main advantage of this control method is that it does not require the use of any current controllers or modulators. The simulation results obtained using MATLAB/Simulink verify the effectiveness of the proposed method.

Simplifying Nonlinear Control Design with Reduced-Complexity T-S Fuzzy System

2023-04-30T21:34:03+07:00

This work introduces a new method to decrease the complexity of Takagi-Sugeno (TS) representations with sector nonlinearity. Takagi-Sugeno (TS) fuzzy control is a structured method deal with managing non-linear systems, first introduced in 1985. It depends on the utilization of fuzzy system, which represent a collection of If-Then fuzzy regulations with regional linear descriptions in the consequent parts. The proposed method uses linear interconnections among submodels to simplify the TS fuzzy model, resulting in fewer rules and maintaining equivalence to the original model. The simplified model is demonstrated as a combination of $(p + 1)$ matrices that are affine, with stability analysis and controller design performed using linear matrix inequalities. The suggested technique has been shown on inverted pendulum model, showing the benefits of reduced complexity for of nonlinear control systems. The reduced-complexity model may result in conservative stability conditions compared to the classical TS fuzzy approach, but offers a significant reduction in numerical complexity and increased computational efficiency for complex systems.

Computation of Electromagnetic Parameters of Shunt Reactors Taken Corner Chamfers of Core Block into Account

2023-06-12T08:57:25+07:00

The shunt reactor (SR) is applied in electrical systems to avoid the overvoltage and absorb the reactive power in transmission lines under operation with no or low load conditions. To avoid magnetic saturation, an air gap is designed at the middle of core of SR. However, the size and shape of air gap will influence directly in the distribution of leakage and fringing fluxes. This leads to uneven distribution of flux density in the SR core and generate electromagnetic forces (EMF) acting on the core and windings of the SR. The electromagnetic forces tend to push/compress the SR core with the different directions, causing oscillation, vibration, and generating audible noise, affecting the operation of the SR. Recently, many papers have studied the SR with one or several air gaps. For the one air gap, it usually has a large size, which leads to a significant leakage and fringing fluxes. In the case of multiple air gaps, the leakage and fringing fluxes will be smaller, leading to reduction of the EMF acting on the core blocks of SR. However, the use of multiple air gaps will encounter technological difficulties.
In this paper, the corner chamfer of SR core is proposed to investigate the distribution of magnetic fields along the core block and EMF acting on the core, as well. This development is performed with two processes: an analytical model is first presented to define main parameters of SR, then a finite element method is applied to calculate and simulate the electromagnetic parameters such as magnetic fields and electromagnetic forces of the SR. The presented method will be validated on a practical single-phase SR

Nghiên cứu thuật toán phát hiện sự cố điện áp lưới trong hệ điều khiển bộ điều áp liên tục

2023-06-16T16:46:33+07:00

The development of devices that improving the quality of power system has been the focus of considerable research in recent years. This paper introduces the grid voltage fault detection algorithm for control system of Active Voltage Conditioner (AVC). The algorithms are built with the aim to AVC system works fast, accurately even in non-ideal grid conditions. The algorithms will be presented include phase lock loop algorithm, voltage sag/swell detection algorithm and phase sequence checking algorithm. All algorithms are tested and simulated in MATLAB / Simulink.

The Bộ điều khiển kháng nhiễu dựa trên chế độ trượt và khâu quan sát trạng thái cho bộ biến đổi ba pha ba mức hình T trong chế độ chỉnh lưu tích cực

2023-06-22T13:13:43+07:00

Bài báo này trình bày một chiến lược điều khiển chế độ trượt (SMC) mới cho bộ chỉnh lưu ba pha ba cấp loại T (3LT ²). First, a state observer (SOB) was designed based on linear matrix inequality (LMI) to identify the optimal eigenvalues of the state-tracking error function. Second, fixed-time sliding mode control (FTSMC) was constructed to control the system. Third, a disturbance observer (DOB) was designed based on the error signals of the system outputs and observer outputs. The output signals precisely converged to the predefined trajectories in a very short time, with small overshoots and steady-state errors. Fourth, the Lyapunov condition was used to verify the corrections of the proposed controller and observer. The simulation by using Matlab Simulink software was used to show the power of the proposed methods and was compared with the PI (Proportional-Integral) controller.

Design And Optimization of A T-Type Converter based on A Nonlinear Programming Technique

2023-06-15T16:27:31+07:00

High efficiency and high power density are becoming increasingly popular in the design requirements of power electronic converters. In this paper, the design and optimization method of a three-phase T-type converter is discussed. Loss models of the converter are formulated by the conventional method. Switching frequency, peak flux density, number of turns, number of layers, etc., are optimized using a nonlinear programming technique for minimizing the overall converter loss. Simulation results prove that the loss models are reliable. The optimized converter has improved performance with a high efficiency of up to 99.47% and a low-temperature rise of fewer than 50 degrees Celsius on both inductors and semiconductor devices.

Synthesis of an adaptive control system for a class of nonlinear plants with uncertain disturbances

2023-05-10T09:08:21+07:00

This paper presents a method for synthesizing an adaptive control system for a class of nonlinear plants with uncertainty disturbances. With these control plants, we propose an adaptive identified law based on the RBF neural network for the uncertain disturbances component. From the recognition results of uncertain components, the controller for the plant is synthesized based on the sliding mode control principle for the system to track the desired state. The paper’s results are rigorously proven by mathematics; the correctness, reliability, and efficiency are confirmed by simulation on Matlab Simulink software. The control system proposed by the article is simple, easy to implement in engineering, has high control quality, and has good adaptability and disturbance resistance. The research results of the paper provide a new approach to designing control systems for nonlinear plants having the impact of uncertainty disturbances commonly encountered in practical applications such as ships, robots, and many other production systems suitable for industry.