• 대한전기학회논문지:전력기술부문A
• /
• 제48권5호
• /
• pp.494-501
• /
• 1999

In this research, ANN modeling method of SMES unit is developed for stability analysis, and the optimal site is selected to maximize stabilization effect of SMES unit. The ANN is trained by learning data which is obtained through the application of complex test function into the traditional mathematical mode. In order to verify the validity of proposed modeling method, fault data of sample power system is applied to both the traditional and the ANN models. When the response of traditional and proposed models are compared, the average error for the active and reactive power are 2.51[%], and 0.24[%], respectively. From the comparison, the relevance of proposed method is validated. For the transient stability analysis, an application method of the proposed model is presented, and the transient stability performance index, which describes system stabilization effect of SMES at disturbance, is also suggested, and optimal site selection method of SMES is presented. In the viewpoint of the voltage stability, system stabilization criterion of local bus is presented from P­V curve, and then optimal site which can maximize the voltage stabilization of the whole power system, is decided from the proposed voltage stability performance index.

• 전기학회논문지
• /
• 제64권5호
• /
• pp.661-666
• /
• 2015

This paper proposes a method for solving running cost problem by minimizing switching reactive power compensation devices. An objective function was modeled by calculating the weighting value of cost, and a solution was derived using ILP. This paper suggests optimal coordinative control method between FACTS, Shunt Reactors, Capacitors and OLTC. Therefore, it is valuable for decision maker in determining order and capacity of devices which gaining a voltage stabilization. As a result, the objectives of voltage stabilization and cost minimization were achieved simultaneously. This realizes the economic efficiency of the system. We start by showing how to solve systems of linear equations using the language of pivots and tableaus. The effectiveness of this technique is demonstrated in modified PSS/E MIGUM 45 bus system. The simulation results show the effectiveness of this algorithm by comparing the outcome withseveral established methods.

• 전기학회논문지
• /
• 제65권2호
• /
• pp.269-278
• /
• 2016

In order to maintain customer voltages within allowable limit($220{\pm}13V$) as much as possible, tap operation strategy of SVR(Step Voltage Regulator) installed in distribution system is very important, considering the scheduled delay time(30 sec) of SVR. However, the compensation of BESS(Battery Energy Storage System) during the delay time of SVR is being required because the customer voltages in distribution system interconnected with PV(Photovoltaic) system have a difficultly to be kept within allowable limit. Therefore, this paper presents the optimal voltage stabilization method in distribution system by using coordination operation algorithm between BESS and SVR. It is confirmed that customer voltage in distribution system can be maintained within allowable limit($220{\pm}13V$).

• Journal of Electrical Engineering and Technology
• /
• 제12권1호
• /
• pp.11-18
• /
• 2017

In order to maintain customer voltages within the allowable limit($220{\pm}13V$) as much as possible, tap operation strategy of SVR(Step Voltage Regulator) which is located in primary feeder, is widely used for voltage control in the utilities. However, SVR in nature has operation characteristic of the delay time ranging from 30 to 150 sec, and then the compensation of BESS (Battery Energy Storage System) during the delay time is being required because the customer voltages in distribution system may violate the allowable limit during the delay time of SVR. Furthermore, interconnection of PV(Photovoltaic) system could make a difficultly to keep customer voltage within the allowable limit. Therefore, this paper presents an optimal coordination operation algorithm between BESS and SVR based on a conventional LDC (Line Drop Compensation) method which is decided by stochastic approach. Through the modeling of SVR and BESS using the PSCAD/EMTDC, it is confirmed that customer voltages in distribution system can be maintained within the allowable limit.

• 대한전기학회논문지:전력기술부문A
• /
• 제50권7호
• /
• pp.324-332
• /
• 2001

In this paper, it is suggested that the selection method of parameter of Power System Stabilizer(PSS) with robustness in low frequency oscillation for Static VAR Compensator(SVC) using a Real Variable Elitism Genetic Algorithm(RVEGA). A SVC, one of the Flexible AC Transmission System(FACTS), constructed by a fixed capacitor(FC) and a thyristor controlled reactor(TCR), is designed and implemented to improve the damping of a synchronous generator, as well as controlling the system voltage. The proposed PSS parameters are optimized using RVEGA in order to maintain optimal operation of generator under the various operating conditions. To decrease the computational time, real variable string is adopted. To verify the robustness of the proposed method, we considered the dynamic response of generator speed deviation and generator terminal voltage by applying a power fluctuation and three-phase fault at heavy load, normal load and light load. Thus, we prove the usefulness of proposed method to improve the stability of single machine-infinite bus with SVC system.

• 조명전기설비학회논문지
• /
• 제16권2호
• /
• pp.104-112
• /
• 2002

본 논문에서는 FACTS 기기의 일종인 전력조류 극대화 및 제어 기능과 함께 외란에 의한 과도시의 전력계통 안정화 기능을 수행할 수 있는 TCSC용 전력시스템 안정화 장치 설계에 대하여 연구하였다. TCSC용 전력시스템 안정화 장치 설계시 파라미터 선정은 복잡한 수식이 필요 없고 계산시간을 감소시키며 적은 반복횟수로도 최적해를 찾을 수 있는 자연 생태계의 진화를 모의한 유전 알고리즘을 이용하였다. 전력 시스템의 저주파 진동에 강인성을 갖는 TCSC는 TCR(Thyristor Controlled Reactor)과 커패시터의 병렬구조에 의해 용량성과 유도성에 걸친 범위가지 연속적으로 제어할 수 있는 구조로 이루어져 있다. 이러한 제안된 방법의 강인성을 검증하기 위해 여러 가지 운전조건에 대해 전력계통 안정도 및 고유치를 해석하여 기존의 안정화 장치를 적용한 경우와 비교함 으로써 유용성을 입증하였다.