Predefined-time Stabilization of 4D Permanent-magnet Synchronous Motor System with Deterministic and Stochastic Disturbances Using Linear Time-varying Control Input

Nain de la Cruz,Michael Basin 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.6

This paper presents a novel continuous predefined-time convergent control algorithm for higher-order systems with incompletely and completely measured states subjected to deterministic disturbances and stochastic noises. The algorithm enables a control designer to assign the convergence time as a control law parameter of in advance, regardless of initial conditions. The designed control law employs time-varying linear control input terms substituting for previously used exponential ones. The control algorithm efficiency is demonstrated by numerical simulations for a four-dimensional (4D) permanent-magnet synchronous motor (PMSM) system with incompletely and completely measured states affected by both deterministic disturbances satisfying Lipschitz conditions and stochastic white Gaussian noises. The numerical simulations confirm the algorithm efficiency in each considered case. To the best of the authors’ knowledge, this is the first attempt to design a predefined-time convergent continuous control law for higher-order systems with incompletely measurable states subjected to both deterministic disturbances satisfying Lipschitz conditions and stochastic white Gaussian noises, using a linear time-varying control input.

무용 숙련성과 템포에 따른 타이밍 제어 특성

남수미 ( Soo Mi Nam ),고지현 ( Ji-hyun Ko ),정재욱 ( Jaeuk Jeong ),김민주 ( Min Joo Kim ) 한국스포츠심리학회 2023 한국스포츠심리학회지 Vol.34 No.2

Purpose: The purpose of this study was to investigate timing control characteristics in synchronization-continuation task that appear according to dance expertise and tempo. Methods: The participants were divided into 12 professional dancers who are active in domestic professional dance troupes and 12 non-dancers. The task was to synchronize finger tapping according to auditory stimuli provided periodically under three tempo conditions (60, 120, 180 bpm) and than continue tapping at the reference tempo without auditory stimuli. The timing accuracy of synchronization task was calculated as the absolute error of asynchrony, and timing variability was calculated as the standard deviation of asynchrony. The difference between the inter-tap interval (ITI) and the target time was calculated as timing accuracy, and the standard deviation of ITI was calculated as timing variability in the continuous task. Results: In the synchronization task, the timing accuracy was highest in the 120bpm condition, and the timing variability of the experts was lower in the 60 and 120bpm compared to the novice. Timing variability in the continuation task was lower in the skilled group than in the inexperienced group, and higher than in other tempo conditions at 60bpm. Conclusion: Through these research results, dancers are specialized in creating and maintaining regular movements without auditory stimulation as well as consistently moving in accordance with periodic rhythms, and long-term dance training experience has a positive effect on promoting these abilities.

Synchronization of a Class of Time-varying Delay Chaotic Systems with External Disturbances via Impulsive Intermittent Control

Meichun Huang,Runzi Luo,Jiaojiao Fu,Haipeng Su 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.5

The main goal of this article is to consider the synchronization of a class of chaotic systems with timevarying delay and external disturbances. A new control method, which is the impulsive intermittent control strategy, is proposed. In our control scheme, the time interval between impulsive control and intermittent control is variable. In addition, the “working time” interval and the “rest time” interval of intermittent control are also changeable. By designing an impulsive intermittent controller, a new asymptotic stability theorem is obtained to ensure the asymptotic synchronization of a class of time-varying delay chaotic systems with variable external disturbances. Numerical simulations are given to demonstrate the applicability and validity of the proposed scheme.

Finite-time Function Projective Synchronization in Complex Multi-links Networks and Application to Chua’s Circuit

Xi Wang,Peng Miao 제어·로봇·시스템학회 2020 International Journal of Control, Automation, and Vol.18 No.8

The article focuses on the problem of finite-time function projective synchronization which is happened in complex multi-links networks with constant time delay or time-varying delay problems and it is applied to Chua’s circuit. The main contribution is that a special class of nonlinear feedback controllers are proposed to make finitetime function projective synchronization. The proposed two nonlinear feedback controllers contain the constant time delay or time-varying delay and they all can make finite-time function projective synchronization in complex multi-links networks with constant time delay or time-varying delay problems. In addition, their finite-time criteria are derived based on finite-time stability theory and the convergence time are estimated. At last, the presented controllers are applied to Lorenz system and Chua’s circuit the numerical simulations demonstrate the power of our method.

Fixed/preassigned-time Synchronization of Memristive Neural Networks With Mixed-time Delays via Event-triggered Control

Jiashu Gao,Guodong Zhang,Leimin Wang 제어·로봇·시스템학회 2025 International Journal of Control, Automation, and Vol.23 No.7

This paper investigates the fixed-time synchronization (FTS) and preassigned-time synchronization (PTS) of memristive neural networks (MNNs) with mixed-time delays. Firstly, by applying Lyapunov stability theory, fixed/preassigned-time stability lemmas and inequality techniques, several results for FTS and PTS of MNNs are achieved. Secondly, the FTS and PTS results in this paper offer faster convergence rate and more accurate settling times than asymptotic and finite-time synchronization. Thirdly, the model incorporates state-dependent switching, time-varying and distributed delays, and the time delays do not require differentiability, which leading to the results of this paper are more general. Additionally, unlike feedback control, an event-triggered control (ETC) strategy has been designed that enhances communication resource efficiency and reduces control costs. Finally, the correctness of the results is validated through a data simulation example.

이중 변환 UPS 병렬 운전의 제어 동특성 향상을 위한 동기 좌표계 전압 제어기 구조

모재성,윤영두,류효준,이민성,최승철,김성민,김석민,강호현,김희중 전력전자학회 2022 전력전자학회 논문지 Vol.27 No.4

This study proposes a voltage control scheme in a synchronous reference frame to improve the dynamic characteristics of double-conversion UPSs. UPSs need to control positive and negative sequence voltage, so that positive and negative sequence extractors are generally used to obtain each sequence of the voltage and current. Voltage and current controllers for each sequence are implemented. However, the extractor causes considerable delay, and the delay restricts the control performance, especially for the current controller. To improve the dynamics of the current controller, the proposed scheme adopts a unified current controller without separating positive and negative sequences. By using discrete-time current controller, the control bandwidth can be extended significantly so that negative sequence current can be controlled. To enhance the performance, an additional feed-forward technique for output voltage regulation is proposed. The validity of the proposed controller is verified by experiments.

An Improved Stationary Frame-based Digital Current Control Scheme for a PM Synchronous Motor

Kim, Kyeong-Hwa,Young, Myung-Joong The Korean Institute of Power Electronics 2001 JOURNAL OF POWER ELECTRONICS Vol.1 No.2

An improved stationary frame-based digital current control technique for a permanent magnet(PM) synchronous motor is presented. Generally, the stationary frame current controller is known to provide the advantage of a simple implementation. However, there are some unavoidable limitations such as a steady-state error and a phase delay in the steady-state. On the other hand, in the synchronous frame current regulator the regulated currents are dc quantities and a zero steady-state error can be obtained through the integral control. However, the need to transform the signals between the stationary and synchronous frames makes the implementation of a synchronous frame regulator complex. Although the PI controller in the stationary frame gives a steady-state error and a phase delay, the control performance can be greatly improved by employing the exact decoupling control inputs for the back EMF., resulting in an ideal steady-state control characteristics irrespective of an operating condition as in the synchronous PI decoupling controller. However, its steady-state response may be degraded due to the inexact cancellation inputs under the parameter variations. To improve the control performance in the stationary frame, the disturbance is estimated using the time delay control. The proposed scheme is implemented on a PM synchronous motor using DSP TMS320C31 and the effectiveness is verified through the comparative simulations and experiments.

A Time Synchronized Multi-robot Coverage Algorithm for Unstructured Environment

Tae-Shin Kim,Young-Ho Lee,Jong-Koo Park,Tae-Yong Kuc,Sang-Hoon Ji,Sang-Moo Lee,Yong-Sun Moon 제어로봇시스템학회 2014 제어로봇시스템학회 국제학술대회 논문집 Vol.2014 No.10

This paper considers a design problem for time synchronized coverage control of cooperative mobile robots. The derived algorithm provides a coverage control which not only considers the mobility characteristic of each mobile robot for task allocation but generates robot velocity profile for synchronized coverage completion within the constrained time. Since the environment for robot coverage work is modeled as a set of locations to visit by robots, the derived coverage algorithm and its control method are equally well suited to an unstructured working environment as to the structured work space. In determining the number of locations for each robot to visit during coverage operation, a time index derived from the minimum time velocity profile is used for the comparison of robot performance. Once the set of locations has been determined for each robot, the corresponding path tree and velocity profile are generated for synchronized execution of coverage work. The completeness of synchronized group coverage within the constrained time is proven through simulation for a group of mobile robots with different motor characteristics. An additional consideration by the derived coverage controller is collision avoidance of mobile robots in a crowded environment with the aid of finite potential function approach.

Finite-time Synchronization of Neural Networks with Multiple Proportional Delays via Non-chattering Control

Wanli Zhang,Chuandong Li,Tingwen Huang,Junjian Huang 제어·로봇·시스템학회 2018 International Journal of Control, Automation, and Vol.16 No.5

This paper investigates finite-time synchronization of neural networks (NNs) with multiple proportional delays. In order to cope with the difficulties induced by multiple proportional delays, suitable nonlinear variable transformations and new 1-norm-based analytical techniques are developed. By constructing Lyapunov functional and designing new designed controllers, several new sufficient conditions are derived to realize synchronization in finite time. Moreover, estimation of the upper bound of synchronization time is also provided for NNs with bounded delays or proportional delays. The designed controllers without sign function are simple, which means the chattering phenomenon in most of the existing results can be overcome. A numerical simulation is offered to verify the effectiveness of the theoretical analysis.

Fixed-time Synchronization of Fractional-order Hopfield Neural Networks

Xu Mei,Yucai Ding 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.11

This paper investigates the fixed-time synchronization of fractional-order Hopfield neural networks (FHNNs). The aim of this paper is to design a state-feedback controller to make the synchronization error convergent to zero within bounded time. Based on the Lyapunov function and fractional calculus theory, we derived some criteria of synchronization for delay-free FHNNs and delayed FHNNs, respectively. At the same time, the upper bound of settling time for synchronization are given. Numerical simulations demonstrate the effectiveness of the theoretical analysis.