Control Theory Research Papers - Academia.edu (original) (raw)

- by Enrique Arias
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- Computer Science, Technology, Control Theory, Optimal Control
- by Steve Curtis
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- Engineering, Genetics, Artificial Intelligence, Control Theory

In this paper, we outline the foundations of a general global optimisation strategy for the solution of multilevel hierarchical and general decentralised multilevel problems, based on our recent developments on multi-parametric programming and control theory. The core idea is to recast each optimisation subproblem, present in the hierarchy, as a multi-parametric programming problem, with parameters being the optimisation variables belonging to the remaining subproblems. This then transforms the multilevel problem into single-level linear/convex optimisation problems. For decentralised systems, where more than one optimisation problem is present at each level of the hierarchy, Nash equilibrium is considered. A three person dynamic optimisation problem is presented to illustrate the mathematical developments.

- by Nuno Faísca
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- Applied Mathematics, Control Theory, Business and Management, Nash Equilibrium

For L1 -families of time varying matrices centered at an unper- turbed matrix, the Lyapunov spectrum contains the Floquet spectrum ob- tained by considering periodically varying piecewise constant matrices. On the other hand, it is contained in the Morse spectrum of an associated flow on a vector bundle. A closer analysis of the Floquet spectrum based on geo- metric control

- by Wolfgang Kliemann and +1
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- Control Theory, Pure Mathematics, Spectrum, Lyapunov exponent

Functional analysis is a universal methodology, which is able to support NPP and I&C design process. The paper proposes an approach to combining the functional analysis process and I&C design process into a single I&C functional design process. Operation of a system is considered as a set of functions providing not only the achievement of goal, but also keeping material and energy balances. A notation for graphical representation of semantic network (hierarchy of functions) describing a system is suggested. This network includes four levels, namely functional goals, abstract functions level, process functions level, and equipment level. The elements of the hierarchy are connected by three kinds of relationships, namely: parent-child, main-support, and cause-consequence. Then the semantic network (hierarchy) of functions is converted into a functional network which looks as a directed graph. This graph is used for development of control algorithm and for building of instrumentation a...

- by Alexey Anokhin
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- Control Theory, Process Control, Structural Analysis, System Analysis and Design

In recent years, much attention has been focused upon predictive control of nonlinear systems. The implementation of such a control strategy for real processes has greatly improved their performance. This paper deals with a model-based predictive control (MBPC) strategy using a generalised Hammerstein model and its application to the temperature control of a semibatch reactor. Both unconstrained and constrained adaptive control problems are considered. A simple identification method based on the weighted recursive least squares method (WRLS) is used to estimate the model parameters on-line. An indirect adaptive nonlinear controller is designed by combining the predictive controller with an indirect parameter estimation algorithm. This adaptive scheme has been applied for the control of a semi-batch chemical reactor. Experimental results show that the performance of the generalised Hammerstein MBPC (NLMBPC) was significantly better than that of a linear model predictive controller (LMBPC).

- by Ksouri Mekki
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- Engineering, Control Theory, Adaptive Control, Nonlinear Control

The relationship between technocratic and socioideological control in organizations is con- tested among scholars. In an attempt to understand this complex interlinkage, the present study examined organizational control processes in inbound and outbound call centers in Bangalore, India. Relying on qualitative interviews and thematic analysis, the study demonstrated how organizations invoke the concept of professionalism in their employees. Organizational efforts in this direction result not only in employee compliance but also internalization of professional- ism such that agents' sense of self changes to embrace employer-defined professionalism. Socioideological control thus sets the stage for the acceptance and effectiveness of techno- cratic control. Rather than viewing organizational identities and organizational cultures as additional or separate extensions of the substantive, structural, material dimensions of control, the findings of the study highlight that socioideolog...

- by Ernesto Noronha
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- Control Theory, Organizational Culture, Professional Identity, Call Center

The main goal of Transport Channel Synchronization is that frames sent by the RNC arrive in time to the Nodes B for transmission over the air interface. The 3GPP specifies a simple Timing Adjustment algorithm that tracks the delay of the Iub link (interface defined between RNC and Node B) by adding or subtracting a constant step. We show that this scheme reacts too slowly under abrupt delay variations and may become unstable in high delay scenarios. This paper proposes an alternative mechanism denominated Proportional Tracking Algorithm (PTA) which ensures stability in any scenario and improves performance compared to the classic one. The stability analysis of PTA is based on control theory and the performance is measured by means of an UTRAN simulator considering realistic traffic conditions in the Iub.

- by Fernando Cerdan
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- Control Theory, Networking, Stability Analysis

The medical profession has always a high degree of autonomy. However, the rapid growth of health care costs that has started in the second half of the last century, has forced governments to tighten the control over medical practice and introduce managers into medical organizations, and also to induce competitive forces in health care systems. However, there is no conclusive evidence that the juxtaposition of bureaucratic and market control mechanisms with the autonomy of the medical profession has led to cost reduction. These actions strengthened, however, the conflict between the role of a manager focused on cost control and the role of a doctor directed towards quality control. One of the key area where the control mechanisms have low efficacy, is treatment of patients with multi chronic conditions, as in this case, the coordination of the therapeutic process must include the alignment of actions of various specialties. At the organization level bureaucratic mechanisms of coordin...

This paper revisits the use of trend forecasting to determine ordering policy in supply chains by viewing it as a part of the control process for making the supply responsive to demand. Trend forecasting is often used to assess demand—a tracked variable in the control context, which drives supply—a tracking variable. Used in this way, it is often observed to increase instability creating the so-called bullwhip effect. Trend is used on the other hand with reliability to increase stability in controller control, but with the difference that a trend of a ...

- by Khalid Saeed
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- Business, Dynamical Systems, Control Theory, Operations Management

Purpose-The purpose of this paper is to propose mover position control of linear induction motor (LIM) using an adaptive backstepping approach based on field orientation. The obtained results are also compared with conventional backstepping approach to show its performance under parameters variations. Design/methodology/approach-First, the indirect field-oriented control LIM is derived. Then, an adaptive backstepping approach based on field-oriented control of LIM is proposed to compensate the uncertainties which occur in the control. Mover position amplitude tracking objective is formulated, under the assumption of unknown total mass of the moving element, viscous friction, and load force, so that the position regulation is achieved. Findings-The effectiveness and robustness of the proposed control scheme are verified by numerical simulation using Matlab/Simulink model. The numerical validation results of the proposed scheme have presented good transient control performances and robustness to uncertainties compared to the conventional backstepping control design. In addition, the parameter uncertainties of the total mass of the moving element and load force disturbance are compensated using the proposed scheme. Originality/value-The paper presents an adaptive backstepping approach for LIM control that achieves mover position amplitude tracking objective under mechanical parameter variation.

- by A. Hazzab
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- Applied Mathematics, Control Theory, Numerical Simulation, Electric Motor

A design method for variable structure system control is presented. It is based on a differential geometric approach and it is intended to deal with the class of nonlinear systems affine in the control with uncertainties and disturbances. The main goals of the proposed method are: (i) robustness; (ii) tuning simplicity; (iii) chattering reduction; and (iv) reaching mode control. Its application to the wind subsystem of an electricity generation hybrid system is discussed in detail. Extensive simulation experiments were conducted with a comprehensive model of the plant and they are presented to illustrate the controller performance.

- by P. Puleston
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- Mechanical Engineering, Applied Mathematics, Control Theory, Energy Conversion

The paper describes a variable speed wind generation system where fuzzy logic principles are used for efficiency optimization and performance enhancement control. A squirrel cage induction generator feeds the power to a double-sided pulse width modulated converter system which pumps power to a utility grid or can supply to an autonomous system. The generation system has fuzzy logic control with vector control in the inner loops. A fuzzy controller tracks the generator speed with the wind velocity to extract the maximum power. A second fuzzy controller programs the machine flux for light load efficiency improvement, and a third fuzzy controller gives robust speed control against wind gust and turbine oscillatory torque. The complete control system has been developed, analyzed, and validated by simulation study. Performances have then been evaluated in detail.

- by Bimal Bose
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- Control Theory, Wind Energy, Fuzzy Logic, Fuzzy Logic Control

A comprehensive study of capacitor placements and real-time control in general unbalanced distribution systems is undertaken. New developments in a loss reduction formula, problem formulations, solution methodology and mathematical justification are presented. The problem is decoupled into two subproblems: the capacitor placement subproblem and the real-time control subproblem. An effective solution algorithm for placing capacitors and determining their real-time control

This article explores the plausibility of the conflicting theoretical assumptions underlying the main criminological perspectives on juvenile delinquents, their peer relations and social skills: the social ability model, represented by Sutherland's theory of differential associations, and the social disability model, represented by Hirschi's control theory. It does so by applying the principles associated with Granovetter's theory of strong and weak ties, drawing out its theoretical implications for the criminological theories and deriving a number of hypotheses. The article uses "strategic research materials" in the form of a data set strongly biased towards the social disability model and containing information on co-offending relations among a population (N = 580) of juveniles in a Swedish town during a three-year period. Results from cross-sectional empirical analyses using, among other things, the Quadratic Assignment Procedure, clearly support the social ability model. The robustness of the initial analyses is checked through longitudinal analyses applying actor-oriented statistical models for network evolution. The article's implications for criminological, as well as multidisciplinary, research are discussed.

- by Mattias Smångs
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- Sociology, Criminology, Social Networks, Control Theory
- by William Spears
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- Algorithms, Artificial Intelligence, Control Theory, Data Management

Robotic operations carried out via the Internet face several challenges and difficulties. These range from human-computer interfacing and human-robot interaction to overcoming random time delay and task synchronization. These limitations are intensified when multi-operators at multisites are collaboratively teleoperating multirobots to achieve a certain task. In this paper, a new modeling and control method for Internet-based cooperative teleoperation is developed. Combining Petri net model and event-based ...

- by Ning Xi and +1
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- Robotics, Control Theory, Automatic Control, Synchronization
- by Douglas Baxter and +1
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- Control Theory

The design of logic controllers for event-driven systems continue to rely largely on intuitive methods rather than on formal techniques. This approach results in a control code that requires extensive verification, is hard to maintain and modify, and may even fail at times. Supervisory control theory (SCT) provides a formal approach to logic control synthesis. In order to demonstrate the usefulness of the supervisory control theory in manufacturing systems, an educational test-bed that simulates an automated car assembly line has been built using LEGO® blocks. Finite state machines (FSMs) are used for modeling operations of the assembly line, and for the specifications that accomplish the task of successfully completing the assembly repeatedly. Using the technique of SCT, we derive a supervisor that enforces the specifications while offering the maximum flexibility of assembly. Subsequently a controller is extracted from the maximally permissive supervisor for the purpose of implementing the control by selecting, when possible, at most one controllable event from among the ones allowed by the supervisor. Testing to check the correctness of the control code is reduced, since the controller is guaranteed to enforce the specifications.

- by RATNESH KUMAR
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- Engineering, Control Theory, Automata, Automatic Control

We study distributed control design for discrete-event systems (DES) in the framework of supervisory control theory. Our DES comprise multiple agents, acting independently except for specifications on 'global' behavior. The central problem investigated is how to synthesize 'local' controllers for individual agents such that the resultant controlled behavior is identical with that achieved by global supervision.

- by Walter Wonham
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- Mechanical Engineering, Applied Mathematics, Computer Architecture, Control Theory

In classical control theory, tracking refers to the ability to perform measurements and feedback on a classical system in order to enforce some desired dynamics. In this paper we investigate a simple version of quantum tracking, namely, we look at how to optimally transform the state of a single qubit into a given target state, when the system can be prepared in two different ways, and the target state depends on the choice of preparation. We propose a tracking strategy that is proved to be optimal for any input and target states. Applications in the context of state discrimination, state purification, state stabilization, and state-dependent quantum cloning are presented, where existing optimality results are recovered and extended.

- by Paulo Mendonca
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- Measure Theory, Control Theory, Mathematical Sciences, Physical sciences

With the entry of Tasmania into the national electricity market, equipment upgrades are required in many parts of the existing power system. This presents an opportunity to embrace new technology, in order to enhance the current efficiency and productivity of the system. One area is that of hydro-turbine speed governors, an integral part of maintaining the frequency of the output. This paper analyses the current standard control algorithm for turbine governors, the PID controller. It illustrates the processes involved, tuning and their limitations. Finally, alternative control systems are discussed.

- by M. Negnevitsky
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- Engineering, Control Theory, Power System, Control system

5th International Conference on Applied Mathematics and Sciences (AMA 2021)will provide an excellent international forum for sharing knowledge and results in theory, methodology and applications impacts and challenges of Mathematics and Sciences. The conference documents practical and theoretical results which make a fundamental contribution for the development of Mathematics and Sciences. The aim of the conference is to provide a platform to the researchers and practitioners from both academia as well as industry to meet and share cutting-edge development in the field. The goal of this Conference is to bring together researchers and practitioners from academia and industry to focus on Mathematics and Sciences advancements, and establishing new collaborations in these areas. Original research papers, state-of-the-art reviews are invited for publication in all areas of Mathematics.

We introduce dense real-time into the supervisory control framework for discrete event systems. Supervisory control theory models an autonomous plant and its specification as sets of execution traces. The task of a supervisor is to control the plant by disabling certain events so that the closed-loop behavior lies within the specification. We extend this theory to model the real-time aspects of the plant's execution. The two cases of finite (terminating) and infinite (non-terminating) timed traces are discussed. We give necessary and sufficient conditions for the existence of a supervisor. A supervisory synthesis problem is formulated. When the plant and specification behaviors are represented by deterministic timed automata, the synthesis problem can be solved. The synthesis procedure and the synthesized supervisor are polynomial in the number of automata states and exponential in the timing information.

- by Howard Wong-toi and +1
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- Algorithms, Control Theory, Systems Analysis, Automata

This paper presents the distributed formation control of a multi-agent system using graph theory with emphasis on consensus and cooperation issues. The focal point is to achieve and maintain a formation from any initial condition, with and without a leader that the entire formation must follow. Our analysis framework is based on tools from algebraic graph theory, matrix theory and control theory. We present a brief derivation of multi-agent consensus in continuous-time and the corresponding iterative form stated in discrete-time, because while the real scenario is continuous, the implementation that we simulate is discrete. Based on the discrete-time algorithm, we propose a solution to obtain and uphold consensus when there is a leader to command the entire network. Simulation results are presented, indicating the capabilities and limitations of the algorithms.

- by Dario Figueira
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- Control Theory, Graph Theory, Algebraic Graph Theory, Matrix Theory

This paper provides a selective survey of applications of control theory to the analysis of economic policy problems. We discuss applications of closed-loop control and of optimum control theory, including deterministic, stochastic and decentralized optimum control. Promising areas of mutual cooperation between control theorists and economists such as robust control and dynamic game theory are identified. A critical evaluation is given of different control theory approaches to an empirically useful theory of economic policy.

- by Reinhard Neck
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- Economics, Control Theory, Economic policy, Robust control

The study of land cover change is an important problem in the Earth Science domain because of its impacts on local climate, radiation balance, biogeochemistry, hydrology, and the diversity and abundance of terrestrial species. Most well-known change detection techniques from statistics, signal processing and control theory are not well-suited for the massive high-dimensional spatio-temporal data sets from Earth Science due to limitations such as high computational complexity and the inability to take advantage of seasonality and spatio-temporal autocorrelation inherent in Earth Science data. In our work, we seek to address these challenges with new change detection techniques that are based on data mining approaches. Specifically, in this paper we have performed a case study for a new change detection technique for the land cover change detection problem. We study land cover change in the state of California, focusing on the San Francisco Bay Area and perform an extended study on the entire state. We also perform a comparative evaluation on forests in the entire state. These results demonstrate the utility of data mining techniques for the land cover change detection problem.

- by Michael Steinbach
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- Data Mining, Computational Complexity, Control Theory, Time Series

In recent years, it is remarkable to see the increasing number of studies related to the theory and application of fractional order controller (FOC), specially controller, in many areas of science and engineering. Research activities are focused on developing new analysis and design methods for fractional order controllers as an extension of classical control theory. In this paper, a new tuning method for fractional order proportional and derivative ( ) or FO-PD controller is proposed for a class of typical second-order plants. The tuned FO-PD controller can ensure that the given gain crossover frequency and phase margin are fulfilled, and furthermore, the phase derivative w. r. t. the frequency is zero, i.e., the phase Bode plot is flat at the given gain crossover frequency. Consequently, the closed-loop system is robust to gain variations. The FOC design method proposed in the paper is practical and simple to apply. Simulation and experimental results show that the closed-loop system can achieve favorable dynamic performance and robustness.

- by Amjad Khashan
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- Applied Mathematics, Control Theory, Design Methods, Adaptive Control

A new digital control solution to motion control problems is proposed. It is based on a unique active disturbance rejection concept, where the disturbances are estimated using an extended state observer (ESO) and compensated in each sampling period. The dynamic compensation reduces the motion system to approximately a double integrator which can be easily controlled using a nonlinear proportional-derivative controller. The proposed Active Disturbance-Rejection Controller (ADRC) consists of the ESO and the nonlinear PD controller and is designed without an explicit mathematical model of the plant. Hence the controller is inherently robust against plant variations. Through simulation, frequency response analysis, and hardware tests, it is shown that the proposed approach is superior to the current PID based technology. It stands out especially in handling set point change, large inertia and friction variations, and external torque disturbance, all of which is seen as "disturbance" by ADRC and is actively compensated. The improvement in transient response and steady state error is also quite evident.

- by Fangjun Jiang
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- Control Theory, Motion control, Digital Control, Control Systems

In this project a remote controlled self-balancing mobile robot was designed, built and controlled. This paper gives a summary of the work done in the fields of mechanical design, electronics, software design, system characterization and control theory. This wide array of fields necessary for the realization of the project holds the project up as a leading example in the field of mechatronics. In the paper special focus will be on the modelling of the robotic system and the simulation results of various control methods required for the stabilization of the system.

- by Tomislav Tomašić
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- Computer Science, Control Theory, Inverted Pendulum, Pid

The paper deals with methods of identification of the parameters of an induction motor model using genetic algorithms. It is supposed that the inverter supplying the motor is directly accessible for control of the conduction sequences of its power switches. This makes it possible to carry out a test consisting of a transient from standstill to steady-state operation at a given frequency and successive free motion to standstill. During this test, data are acquired referring to stator voltages, and currents and speed. Then, a genetic algorithm is employed with the aim of determining the mechanical and electrical parameters of the model, so as to reproduce the input-output behaviour of a real open-loop system.

Given an ideal I in , the polynomial ring in n-indeterminates, the affine variety of I is the set of common zeros in n of all the polynomials that belong to I, and the Hilbert Nullstellensatz states that there is a bijective... more

- by Shiva Shankar
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- Mathematics, Applied Mathematics, Control Theory, PDE (Mathematics)

Based on expectancy theory, goal-setting theory and control theory, we propose a model in which perceived fairness mediates the relationship between characteristics of employee performance management (PM) systems and their perceived effectiveness by employees. PM system characteristics we propose are the frequency and length of formal reviews, the frequency of informal reviews and feedback, whether the formal conversation focused on evaluation or development and finally the degree of participation. The model was tested on a cross-industry sample of 3192 employees in Belgium. The measurement and structural models were simultaneously tested using structural equation modeling, and we used a bootstrapping approach to test the mediation hypothesis. Our findings indicate that performance review focus and employee participation strongly relate to perceptions of appraisal fairness and PM system effectiveness and that the frequency of informal performance reviews is stronger related to PM system effectiveness than the frequency of formal performance reviews. This suggests that the manifest expressions of PM have more impact on PM system effectiveness rather than the more latent characteristics of PM systems. The findings advance research to the role and functionality of PM systems by showing that (a) the manner in which PM systems are shaped and executed is of fundamental importance for their effectiveness, (b) fairness partially mediates the relationship between PM system characteristics and their effectiveness and (c) the three motivational theories appear useful for understanding the consequences of PM practices on individual employees.

- by Herman van Dijk
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- Marketing, Control Theory, Performance Management, Human Resource Management

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- by Edwin Yaz
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- Mechanical Engineering, Applied Mathematics, Control Theory, Nonlinear filters

This paper is concerned with robust stability and robust stabilization problems of uncertain linear systems with delayed state and delayed input respectively. The admissible uncertainty of the systems considered in this paper appears in quadratic constrained forms which take the wellknown norm-bounded time-varying uncertainty as a special case. Delay-dependent results for the two addressed problems are derived using Razumikhin stability theorem and further algorithms are proposed which enable us to nd suboptimal upper bounds for both cases and the controller gain matrix for the stabilization case using linear matrix inequalities (LMIs) technique.

- by Kemin Zhou and +2
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- Mechanical Engineering, Applied Mathematics, Control Theory, Optimal Control

Abstract—This paper provides a theoretical framework for analysis of consensus algorithms for multi-agent networked systems with an emphasis on the role of directed information flow, robustness to changes in network topology due to link/node fail-ures, time-delays, and performance guarantees. An overview of basic concepts of information consensus in networks and methods of convergence and performance analysis for the algorithms are provided. Our analysis framework is based on tools from matrix theory, algebraic graph theory, and control theory. We discuss the connections between consensus problems in networked dynamic systems and diverse applications including synchronization of coupled oscillators, flocking, formation control, fast consensus in small-world networks, Markov processes and gossip-based algorithms, load balancing in networks, rendezvous in space, dis-tributed sensor fusion in sensor networks, and belief propagation. We establish direct connections between spectral and ...

- by Alex Fax
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- Computer Science, Biomedical Engineering, Control Theory, Algebraic Graph Theory

Pain is a sensory experience and distinct from nociception, which refers to the neural mechanisms involved in detecting tissue damage. This article reviews nociceptive mechanisms and how these relate to pain sensation. The emphasis is on recent advances in our understanding of nociceptive mechanisms, including transduction at the peripheral nociceptor terminal, ascending pathways, and the cortical role in pain. Plasticity in nociceptive systems and a new role for descending systems in pain facilitation are also discussed.

- by sam rodgers
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- Nursing, Surgery, Control Theory, Second Order
- by Shlomo Engelberg
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- Control Theory, Control Systems, Feedback, Matrix

A model based on fuzzy logic is proposed for inventory control. The periodic review model of inventory control with variable order quantity is considered. The model takes into account the dynamics of production–inventory system in a control theoretic approach. The control module combines fuzzy logic with proportional-integral-derivative (PID) control algorithm. It simulates the decision support system to maintain the inventory of the finished product at the desired level in spite of variations in demand. The effectiveness of the proposed control model is illustrated using the actual data of a typical packaging organization operating in the Sultanate of Oman.

- by Biswanath Samanta
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- Computer Science, Control Theory, Fuzzy Logic, Fuzzy Logic Control

This paper explains the implementation of a small-signal model for a new five-level series resonant inverter structure. The proposed circuit combines the advantages of multilevel inverters and the characteristics of the physical phenomena, resonance. The small-signal model offers the possibility to design a linearized linear time-invariant (LTI) model around an equilibrium point based on the first-order Taylor series. After that, the performance of the proposed five-level series resonant inverter and its small-signal model are evaluated in MATLAB/Simulink environment. Compared with a MATLAB model generated using the system identification toolbox, the developed small-signal model exhibited a good accuracy in frequency and time domains. In addition, a hardware test bench is developed to validate the proposed model. Both simulation and experimental results show that the proposed multilevel resonant inverter is very interesting for high-voltage high-frequency applications. As a perspective, from the results obtained, we suggest the use of small-signal AC analysis for multilevel series resonant inverter modeling. The paper contains rich information on the recently used tools for dynamic systems modeling and analysis of nonlinear processes that can be applied to modeling and analyzing other power electronics inverters.

Magnetic bearing technology is now rapidly being introduced to industrial applications. The most popular configuration applied is the "classical" one of gap sensor, current control, current-amplifier and magnetic coil. Here we present a magnetic levitation method which combines all the known advantages of active magnetic bearings in a self-sensing configuration. The novel method realizes stable and well damped levitation without any sensor hardware at the rotor. This is achieved by using the coil voltage of the magnetic bearing as system input (voltage instead of current amplifiers) and the current as system output. It is demonstrated that the resulting system is observable and controllable in the sense of control theory, allowing a magnetic bearing to be stabilized with a simple linear controller using current measurements alone. Several self-sensing bearings have been constructed at our lab. Their performance is comparable to systems with sensors, but hardware requirements and costs are substantially reduced. Experimental results are included.

- by Hannes Bleuler
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- Engineering, Control Theory, Energy Conservation, Technology Assessment

A common approach to the modeling of temperature evolution in a multi-zone building is to use thermal resistance and capacitance to model zone and wall dynamics. The resulting thermal network may be represented as an undirected graph. The thermal capacitances are the nodes in the graph, connected by thermal resistances as links. The temperature measurements and temperature control elements (heating and cooling) in this lumped model are collocated. As a result, the input/output system is strictly passive and any passive output feedback controller may be used to improve the transient and steady state performance without affecting the closed loop stability. The storage functions associated with passive systems may be used to construct a Lyapunov function, to demonstrate closed loop stability and motivate the construction of an adaptive feedforward control to compensate for the variation of the ambient temperature and zone heat loads (due to changing occupancy). The approach lends itself naturally to an inner-outer loop control architecture where the inner loop is designed for stability, while the outer loop balances between temperature specification and power consumption. Energy efficiency consideration may be added by adjusting the target zone temperature based on user preference and energy usage. The initial analysis uses zone heating/cooling as input, but the approach may be extended to more general model where the zonal mass flow rate is the control variable. A fourroom example with realistic ambient temperature variation is included to illustrate the performance of the proposed passivity based control strategy. I. INTRODUCTION

This paper focuses on the temperature control in a multi-zone building. The lumped heat transfer model based on thermal resistance and capacitance is used to analyze the system dynamics and control strategy. The resulting thermal network, including the zones, walls, and ambient environment, may be represented as an undirected graph. The thermal capacitances are the nodes in the graph, connected by thermal resistances as links. We assume the temperature measurements and temperature control elements (heating and cooling) are collocated. We show that the resulting input/output system is strictly passive, and any passive output feedback controller may be used to improve the transient and steady state performance without affecting the closed loop stability. The storage functions associated with passive systems may be used to construct a Lyapunov function, to demonstrate closed loop stability and motivates the construction of an adaptive feedforward control. A four-room example is included to illustrate the performance of the proposed passivity based control strategy.

- by Sumit Mukherjee
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- Control Systems Engineering, Control Theory, Renewable Energy, Energy
- by Robert Koelbl and +1
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- Control Theory, Strategic Planning, Urban And Regional Planning, Transport policy

An algorithm for iterative learning control is proposed based on an optimisation principle used by other authors to derive gradient-type algorithms. The new algorithm is a descent algorithm and has potential benefits which include realisation in terms of Riccati feedback and feedfonvard components. This realisation also has the advantage of implicitly ensuring automatic step-size selection and hence guaranteeing convergence without the need for empirical choice of parameters. The algorithm achieves a geometric rate of convergence for invertible plants. One important feature of the proposed algorithm is the dependence of the speed of convergence on weight parameters appearing in the norms of the signals chosen for the optimisation problem.