147 research outputs found

    Decentralized Tracking Controller Design using Proportional-Integral Sliding Mode Control

    Get PDF
    This paper proposes a decentralized tracking controller for a class of nonlinear inter-connected uncertain systems with matched uncertainties. A robust decentralized sliding mode controller is derived such that for each sub system, the actual trajectory tracks the desired trajectory using only the local states information. The Proportional Integral (PI) sliding mode is chosen to ensure the stability of the overall dynamics during the entire period i.e. the reaching phase and the sliding phase. A simulation study is presented to illustrate the effectiveness of the controller

    A Scheme for Controlled Islanding to Prevent Subsequent Blackout

    Get PDF
    The power systems operated by the utilities in developing countries suffer from a large gap between demand and generation,inadequate transmission capacity, and nonuniform location of the load centers and generating stations. Occurences of faults in such systems, in most of the cases, end up with the worst consequences (i.e., complete blackout). This paper illustrates the way a blackout can be prevented in real time through controlled segregation of a system into a number of viable islands together with generation and/or load shedding. The nature and location of any fault that warrants such islanding can be ascertained in real time through monitoring the active-power (megawatt) flows at both ends of a number of prespecified lines. The blackout of June 20, 1998 in the Bangladesh Power Development Board system has been used as an example in this illustration. The philosophy of the proposed islanding scheme may be considered for implementation in other power systems also

    A class of proportional-integral siding mode control with application to active suspension system

    Get PDF
    The purpose of this paper is to present a new robust strategy in controlling the active suspension system. The strategy utilized the proportional-integral sliding mode control scheme. A quarter-car model is used in this study and the performance of the controller is compared to the linear quadratic regulator and with the existing passive suspension system. A simulation study is performed to prove the effectiveness and robustness of the control approach

    OPTIMAL CABLE SELECTION IN RADIAL DISTRIBUTION NETWORKS CONSIDERING PLANNER'S DEFINED VOLTAGE DROP LIMIT

    Get PDF
    New computer algorithms are provided to determine the optimal cable size selection considering radial distribution networks and planner of power distribution defined allowable voltage drop all over the networks. The planner should properly populate the location of all load substations and joint node location in the input data source. Distance calculation of the demand node to demand node and joint node to joint node etc. depends on the geo-graphical location of the defined node. Cable size and type of all feeder segment determination depends on the total cost of the networks, cost of feeder losses etc. An acceptable voltage profile will be maintained all point of the entire networks. The resource of the cable inventory is also responsible for optimal selection of the cable. By using this proposed computer algorithm and program an example is solved successfully that is presented in the results

    Novel adaptation of the critical clearing angle formula for faults on a three phase and a six phase line

    Get PDF
    Enhanced power transfer through polyphase conversion of a transmission line, specially three to six phase, as an alternative to upgrading the conventional three phase power transmission voltage is becoming an area of growing interest in the power industry. Among others this conversion will have an impact on the system stability. While the well-known symmetrical component method has been found suitable in modeling the unsymmetrical faults of a three phase system for transient stability analysis it appeared as difficult-to-apply for six phase system. In this paper a new technique has been proposed to determine the stability in terms of critical clearing angles for both three and six phase line faults. The method has been validated by applying it first for the faults on a 132 kV three phase double circuit line of a given practical power system and comparing the results with those obtained through the symmetrical component method. Then it has been applied for the faults on the same line but considered to have been converted into a 132 kV six phase single circuit line. The method, though an approximate one, is straightforward, simpler and faster than the symmetrical component method and provides sufficiently accurate results

    Proportional-Integral Sliding Mode Tracking Controller with Application to a Robot Manipulator

    Get PDF
    This paper presents the development of a Proportional-Integral sliding mode controller to control a class of uncertain systems. It is assumed that the plant to be controlled can be represented by its nominal and bounded parametric uncertainties. A robust sliding mode controller is newly derived so that the actual trajectory tracks the desired trajectory as closed as possible despite the non-linearities and input couplings present in the system. The Proportional-Integral sliding mode is chosen to ensure the stability of overall dynamics during the entire period i.e. the reaching phase and the sliding phase. The controller is applied to the control of a two-link planar robot manipulator

    Sliding mode control of active suspension system

    Get PDF
    The purpose of this paper is to present a new approach in controlling an active suspension system. This approach utilized the proportional integral sliding mode control scheme. Using this type of sliding surface, the asymptotic stability of the system during sliding mode is assured compared to the conventional sliding surface. The proposed control scheme is applied in designing an automotive active suspension system for a quarter-car model and its performance is compared with the existing passive suspension system. A simulation study is performed to prove the effectiveness of this control design

    SECURE AND EFFICIENT METHOD FOR DYNAMIC ECONOMIC LOAD DISPATCH IN LARGE POWER SYSTEMS

    Get PDF
    This paper presents an efficient and secure method of solving dynamic economic load dispatch (DELD) scheduling problems for large-scale power system operation systems. The main objective is to reduce the total operation costs into the lowest possible level while considering system operation constraints. The method uses LaGrangian Relaxation Method, Linear Programming and other techniques. The algorithm used appears to be efficient and secure to meet the required scheduling objectives of the system. After real system individual generators are economically loaded and periodically dispatched, optimized total generation cost and fast computation times have been achieved. DELD with different period intervals has been taken into consideration. Promising results have been achieved using different real data systems

    SLIDING MODE CONTROL OF A CLASS OF MISMATCHED UNCERTAIN SYSTEMS

    Get PDF
    A proportional-integral sliding mode control is proposed for a system with mismatch uncertainties. The proposed controller gives robust stability for system in the presence of parameters variations, uncertainties and disturbances. A simulation study for as numerical example is given to illustrate the effectiveness of this control design

    Sliding Mode Control for a Class of Uncertain Dynamic Systems with Mismatched Uncertainties

    Get PDF
    This paper focused on the proportional-integral sliding mode control for uncertain dynamic systems with mismatch uncertainties. First, the switching surface condition for the sliding mode control is synthesized. Then the control law is designed to drives the state trajectories of the system onto the sliding surface and the system remains in it thereafter. The proposed control law is able to minimize the effects of the mismatched uncertainty upon the dynamic performance prescribed by the switching surface. A simulation study for a numerical example is given to illustrated the effectiveness of this control designs
    • …
    corecore