Masahiro Furukakoi

Voltage stability improvement to power systems with energy storage systems

Due to the deregulation of the electricity market, the power system is recently placed under more severe operating conditions than ever before. Therefore, voltage stability analysis is a major concern in power system operation. This paper proposes a method to improve the voltage stability of the power system by using the active and reactive power information of the transmission line in accordance with the voltage stability index. Installing a battery at the load substation in order to inject the proper amount of active power and reactive power can improve the voltage stability of the system as shown by simulations.

Optimal Economical Sizing of Grid-Connected Hybrid Renewable Energy System

In this paper, an optimized model is proposed to find the best values for decision variables to optimize the grid connected hybrid renewable energy system which consists of photovoltaic panels, wind turbines and battery bank for electrification to North-east region of Afghanistan to meet winter power shortages of the area. In the proposed model, there are three decision variables namely, the total area occupied by the set of PV panels, total swept area by the rotating turbines’ blades, and the number of batteries. GA (genetic algorithm) is defined to find the optimal values of the decision variables. The objective of this research is to minimize the LCC (life cycle cost) of the hybrid renewable energy system, and ensuring at the same time systems reliability level which is measured in terms of LPSP (loss of power supply probability).

Multi-Objective Optimal Operation for Transmission Systems Considering Voltage Stability

Abstract Due to the liberalization of electric power market, many power producers are entering into the power market. Most of electric power company have been introduced renewable energies that might increase the power system uncertainty. Therefore, it is expected that rise might the likelihood of voltage instability and voltage collapse. In addition, fluctuations in supply and demand are increased by the introduction of a renewable energies. However, by using the Energy storage systems (ESS), the power fluctuations can be reduced. On account of this, we suggest the optimal operation method of the generator and the ESS by considering the voltage stability in this paper. The effectiveness of the proposed method is verified by simulation results in the Matlab/simulink.

Optimal operation for transmission systems with uncertainty of demand forecasting and voltage stability

In recent years, most of the electric utilities have been introduced renewable energy that will increase the power system uncertainty. Thus, the demand curve is hard to predict since the renewable energies fluctuate irregularly. Moreover, it is expected that it will increase the likelihood of voltage instability. In this paper, we suggest the optimal operation method for transmission systems with the uncertainty of demand prediction and voltage stability. The optimal operation that corresponds to the uncertainty of load demand and the operational maintaining the voltage stability can be achieved by the proposed method in this paper.

Optimum capacity of energy storage system considering solar radiation forecast error and demand response

Most of electric power companies have introduced renewable energy which increases the power system uncertainty. It is expected that it increases the surplus and deficiency in power system supply. Thus, an energy storage systems and demand response are required for adjusting supply and demand. On the other hand, the power industries are exposed to competition, and needs an optimal operation to maximize their profits. So, Unit Commitment (UC) becomes an important issue. In this paper, the optimum capacity of energy storage system and demand response for UC in proposed.

An Optimization Approach for Unit Commitment of a Power System Integrated with Renewable Energy Sources: A Case Study of Afghanistan

This paper focused on generation scheduling problem with consideration of wind, solar and PHES (pumped hydro energy storage) system. Wind, solar and PHES are being considered in the NEPS (northeast power system) of Afghanistan to schedule all units power output so as to minimize the total operation cost of thermal units plus aggregate imported power tariffs during the scheduling horizon, subject to the system and unit operation constraints. Apart from determining the optimal output power of each unit, this research also involves in deciding the on/off status of thermal units. In order to find the optimal values of the variables, GA (genetic algorithm) is proposed. The algorithm performs efficiently in various sized thermal power system with equivalent wind, solar and PHES and can produce a high-quality solution. Simulation results reveal that with wind, solar and PHES the system is the most-cost effective than the other combinations.

New optimization method considering combinatorial and multi-objective optimization problem for distribution systems

This paper proposes a new optimization method for distribution system, that method includes combinational problem (CP) as factor in multi-objective optimization problem (MOOP). Increasing load demands and deep penetration of distributed generators (DGs) using renewable energy sources (RESs) has been a cause of concern to protect the smart grid. System. As a t, it causes voltage deviation and reverses power flow. In order to solve these problem, protection devices have to be installed in distribution system. However, it is necessary to consider multi objects to realize safety system, generally these objects are also conflicting with each other. Moreover, it is also important problem to calculate operating cost and finding optimal placement of control devices. This proposed method provides an application for distribution system.