معرفی روشی کاربردی مبتنی بر کنترل برای سنجش شدت رفتار غیرخطی سیستم با استفاده از Gap Metric

نوع مقاله : مقاله برق

نویسنده

استادیار، دانشکده مهندسی برق و کامپیوتر، مجتمع آموزش عالی فنی و مهندسی اسفراین

چکیده

در این مقاله‏‌ یک روش کاربردی برای سنجش رفتار غیرخطی سیستم‌های دارای دینامیک غیرخطی ارائه می‌شود. در این روش، سیستم غیرخطی در فضای کاری خود و با استفاده از ابزار هوشمند gap metric به یک بانک از مدل‌های خطی تقسیم شده و با محاسبه آستانه پایداری بیشینه، توانمندی هر یک از کنترل‌کننده‌های محلی در پایدارسازی مجموعه مدل‌های خطی مورد بررسی قرار می‌گیرد. سپس معیاری برای سنجش شدت رفتار غیرخطی سیستم تحت مطالعه ارائه می‌گردد که دارای مقادیری بین صفر تا یک است. برخلاف بسیاری از روش‌های سنجش شدت رفتار غیرخطی، روش ارائه شده در این پژوهش برای سیستم‌های انتگرالی و ناپایدار نیز قابل استفاده است. علاوه بر این، روش ارائه شده کفایت استفاده از تنها یک کنترل‌کننده خطی و یا لزوم استفاده از روش مدل‌های چندگانه جهت نیل به اهداف حلقه بسته را پاسخ می‌دهد و از افزونگی کنترل‌کننده‌های محلی جلوگیری می‌نماید. برای ارزیابی روش ارائه شده، یک سیستم غیرخطی CSTR شبیه‌سازی شده است که نتایج بدست آمده نشان می‌دهند معیار معرفی شده برای سنجش شدت رفتار غیرخطی عملکرد مناسبی دارد.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

An Applicable Control-Relevant Method for Nonlinearity Assessment using Gap Metric

نویسنده [English]

  • Mahdi Ahmadi
Faculty of Electrical and Computer Engineering, Esfarayen University of Technology, North-Khorasan, Iran.
چکیده [English]

In this paper, an applicable control-relevant nonlinearity assessment method is proposed for nonlinear dynamic systems. In this method, nonlinear system is decomposed to a bank of linear systems using gap metric, a smart tool for measuring the distance between two linear systems. Then, the ability of each local linear models are investigated to stabilize all linear models. A criterion is proposed to measure the nonlinearity of nonlinear system based on gap metric and maximum stability margin values which bounded between 0 and 1. Unlike most of the current nonlinearity measurement, the proposed method could be used for both integrating and unstable nonlinear systems. Besides, the presented method supplies to distinguish that a single linear controller is adequate to control the nonlinear system or it is necessary to employ the multi-model based controllers design methods. Therefore, the redundancy problem could be avoided by employing the proposed method. A nonlinear Continues Stirred Reactor Tank (CSTR) process is studied and results confirm the capability of presented nonlinearity assessment method.

کلیدواژه‌ها [English]

  • Nonlinear System
  • Nonlinearity Assessment
  • Controller
  • Gap Metric
  • Maximum Stability Margin
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