This paper presents a new formulation for power system sectionalizing device placement taking into consideration outage, maintenance and investments costs. The formulation of sectionalizing switches is a combinatorial constrained optimization problem with a nonlinear, nondifferentiable objective function. A solution methodology based on the optimization technique of simulated annealing, is proposed to determine: (i) the number of sectionalizing switches; and (ii) the locations of the switches. The proposed solution methodology can offer a global optimal solution for the sectionalizing device placement problem which includes the reliability, investment and maintenance costs.

Optimal switching device placement in radial distribution systems

This paper proposes a method to evaluate the worth of installing renewable distributed generation (DG) in distribution networks. Moreover, the work optimally allocates these DG units in the distribution network to maximize the worth of the connection to the local distribution company (LDC), as well as the customers connected to the system. The proposed methodology helps the LDC to better assess the benefits of the renewable DG units' proposed connections and to identify the optimal buses on which to connect these DG units. The benefits considered in this paper are deferral of upgrade investments, reduction of the cost of energy losses, and reliability improvement, which is represented by the interruption cost reduction. The proposed methodology takes into consideration the uncertainty and variability associated with the output power of renewable DG as well as the load variability. The planning problem of determining the optimal location and sizes of DG units is defined as multi-objective mixed integer programming.

DG allocation for benefit maximization in distribution networks

To enhance the cost effectiveness of the distribution automation system (DAS), this paper proposes the immune algorithm (IA) to derive the optimal placement of switching devices by minimizing the total cost of customer service outage and investment cost of line switches. The reliability index of each service zone defined by the boundary switches is derived to solve the expected energy not served due to fault contingency, and the customer interruption cost is then determined according to the customer type and power consumption within the service zone. To demonstrate the effectiveness of proposed IA methodology to solve the optimal placement of line switches, a practical distribution system of Taiwan Power Company (Taipower) is selected for computer simulation to explore the cost benefit of line switch placement for DAS

Optimal placement of line switches for distribution automation systems using immune algorithm

Automation is acknowledged by distribution utilities as a successful investment strategy to enhance reliability and operation efficiency However, practical approaches that can handle the complex decision-making process faced by decision makers to justify the long-term financial effects of distribution automation have remained scarce An automated and remote-controlled sectionalizing switch play a fundamental role in an automated distribution network This paper introduces a new optimization approach for distribution automation in terms of automated and remotely controlled sectionalizing switch placement Mixed-integer linear programming (MILP) is utilized to model the problem The proposed model can be solved with large-scale commercial solvers in a computationally efficient manner The proposed sectionalizing switch placement problem considers customer outage costs in conjunction with sectionalizing switch capital investment, installation, as well as annual operation and maintenance costs The effectiveness of the proposed approach is tested on a reliability test system and a typical real size system The presented results indicate the accuracy and efficiency of the proposed method

Optimized Sectionalizing Switch Placement Strategy in Distribution Systems

This paper presents a method to determine optimal operating strategy for distributed generation (DG) incorporating reliability worth evaluation of a distribution system. The use of DG for peak shaving could reduce the overall system operating cost and its use as standby power could reduce the customer interruption cost. If the DG operating cost is less than the utility power cost at peak time, DG should be employed to reduce the overall system operating cost. However, when customer interruption cost is also an important concern, standby power strategy for DG may be better than peak shaving. The reliability worth and the power cost evaluations are needed to determine whether DG should be operated for peak shaving or as standby power. The hourly reliability worth is incorporated in the strategy proposed in this paper to determine the optimal operating decision for the DG. Using the approach proposed in this paper, the distribution companies could determine the optimal operating strategy for their DG.

Optimal operating strategy for distributed generation considering hourly reliability worth

A common approach used in quantifying the worth or benefit of electric service reliability is to estimate the customer costs (monetary losses) associated with power interruptions. Customer surveys are often used to determine interruption costs. The IEEE Power Systems Research Group has conducted surveys of Canadian electric utility customers in the residential, commercial and industrial sectors. These surveys were sponsored by the Natural Sciences and Engineering Research Council and seven participating utilities. This paper presents the overall results of these surveys with emphasis on the cost results. >

A Canadian customer survey to assess power system reliability worth

The authors describe the evaluation of the worth or value of distribution system reliability using quantitative reliability analysis and customer interruption costs. The ability to assess reliability worth makes it possible to optimize the reliability of a system by comparing the reliability worth with the associated system investment costs. The analyses include an evaluation of the reliability of different design/operating configurations of a distribution system and the corresponding reliability worths at the customer level. The reliability of each system configuration is evaluated in terms of the system performance indices and the expected customer outage costs due to power interruptions. >

J. Aweya

Papers

A Canadian customer survey to assess power system reliability worth

Value-based reliability evaluation of electric distribution systems