Search

The objective of this study is to identify and eliminate unnecessary iteration loops in the load flow analysis of an active distribution network so as to improve its overall computational efficiency. The number of iteration loops is minimised through the integrated modelling of a distributed generator (DG) and the associated coupling transformer. The DG bus is not preserved in the load flow calculation and the aforementioned DG-transformer assembly is represented in the form of a voltage-dependent negative load at the point of connection to the main distribution network. Thus, the iteration stage that is involved in indirectly preserving the DG in the form of a voltage source or negative constant power load can be eliminated. This, in turn, eliminates the need for multiple rounds of forward-backward sweeps (FBS) iterations to determine the bus voltages. The power characteristics of the DG-transformer assembly are thoroughly investigated through a carefully performed case study so as to assess the general convergence performance of the proposed load flow algorithm Furthermore, extensive comparative studies are carried out to verify the computational efficiency attained via the proposed DG modelling in the load flow analysis of an active distribution network.

The smart grid is widely considered as the advanced version of the power grid. As an essential characteristic of the smart grid, demand response can reschedule the user’s energy consumption to reduce the operating expense from expensive generators, and further to defer the capacity addition in the long run. Demand Response functions as a vital controller for the present electrical framework. From outsider see the interest reaction can be viewed as two connections, one related to customer viewpoint and the other is pertinent to energy supplier or market administrators. But both links are driven by the application of different computational techniques. Throughout the smart grid, the advanced computational technique has been properly utilized to enhance the outcome and capability of learning. The salient feature of this paper is to criticize the applicability of computational techniques for demand response. The paper explores major aspects such as DR issues, different computational techniques, and future extensions of demand response.

This paper presents the design, application and analysis of low order modified internal model controller (M-IMC) for automatic voltage regulator (AVR). The drawback of traditional IMC (T-IMC) is the poor input and output disturbance rejection performances that play the key role in AVR for industrial applications. The performance of AVR with M-IMC is compared to T-IMC and ZN tuned PID controller. To the design of low order IMCs, the Routh approximation, improved pole clustering, and truncation methods are applied for the reduction of order of AVR system. The low order controllers are reduces the complexity and computational time of overall system.

The objective of this paper is to propose a computationally efficient load flow technique for an unbalanced active distribution network. A modified load flow technique is derived, which is generalized enough for considering various kind of distributed generation resource (DGR) with precise operating characteristics. Constant power voltage (PV) and droop regulated mode of operations are considered for DGR characteristics modelling. Proposed technique is suitable for weakly mesh feeder network since no separate treatment is required. Sequence component frame model is used in the network decoupling for faster computation. Tests are carried out on two different size network to verify accuracy and computation efficiency. Standard IEEE 34 and 123 bus feeder distribution network with some modifications are considered for the case study. Results are validated based on the computation speed and convergence achievement with literature.

The objective of this paper is to improve the accuracy of the results obtained from the load llow analysis of a distribution network via forward-backward sweeps. Specific attention is paid to the two-port modeling of a transformer with precise consideration for the zero sequence components of its port voltages. The zero sequence voltages at transformer ports are often ignored in the conventional load llow analyses. A new two-port network model is derived, which is generalized enough for the accurate representation of a transformer in the cascaded connection. Based upon the novel two-port representation made, a new set of iteration rules is established to carry out the forward-backward sweeps for solving the load llow results. All possible transformer configurations are taken into account. It is shown that the load llow analysis technique proposed is suitable for both active and passive distribution networks. The accuracy analysis of the load llow results is also carried out. For a given load llow result, by assessing the nodal current imbalances are evaluated based upon the admittance matrix representation of the network. Case study is performed to demonstrate the utility of the proposed load llow analysis technique.

This study presents the design of a fuzzy gain scheduled proportional-derivative (FGSPD) controller with integral controller for automatic generation control (AGC) of two-area multi unit power system. The power system investigated comprises of two reheat type thermal units operating in parallel in area-1 and two hydro units of same capacity operating in parallel in area-2. The dynamic response has been studied for step load disturbance in area-1 considering settling times, overshoots and undershoots of the frequency and tie-line power deviations as performance indices. The proposed fuzzy based controller is compared against conventional integral and optimally tuned proportional-integral-derivative (PID) controllers. The Comparative analysis of the performance indicates that the proposed controller gives the best results among all the controllers. The simulations have been performed using Matlab.