• Title/Summary/Keyword: Reactive power compensation

Search Result 298, Processing Time 0.095 seconds

Active/Reactive Compound Compensation in Distribution System

  • Sul, Yong-Tae
    • Journal of Electrical Engineering and information Science
    • /
    • v.2 no.4
    • /
    • pp.46-52
    • /
    • 1997
  • In this paper th use of compensation based on a combination of active plus reactive power at distribution model system is proposed. The basic voltage-power relationships for the linearized case on an infinite bus are used and the compensation angle is defined based on the voltage magnitude response to small power injection. Compensation is supplied at several locations, and the system is subjected to varying fault scenarios, with its response observed under different system conditions. As number of control issues for a storage-based active/reactive power compensator as a bus voltage regulator are explored to compare the effectiveness of active/reactive again reactive-only compensation.

  • PDF

An ANN Controlled Three-Phase Auto-Tuned Passive Filter for Harmonic and Reactive Power Compensation

  • Sindhu, M.R.;Nair, Manjula;Nambiar, T.N.P.
    • Journal of Power Electronics
    • /
    • v.9 no.3
    • /
    • pp.403-409
    • /
    • 2009
  • Automatically tuned passive filters can improve power quality to a great extent in power systems. A novel three-phase shunt auto-tuned filter is designed to effectively compensate source current harmonics and to provide reactive power required by the non-linear load, which draws a highly reactive, harmonic-rich current from the supply. An artificial neural network (ANN) based controller selects filter component values in accordance with reactive power requirement and harmonic compensation. Traditional passive filters are permanently connected to the system and draw large amounts of source current even under light load conditions. By using auto-tuned filters, the passive filter components can be controlled according to load variations and, hence, draw only required source currents. The selection is done by the ANN with the help of a properly tuned knowledge base to provide instantaneous compensation using a digital controller.

Analysis of the Distribution STATCOM Operating Results for Improving Distribution System Power Quality (전력품질 향상을 위한 배전용 STATCOM 운전결과 분석)

  • 오관일;전영수;박상태;추진부
    • The Transactions of the Korean Institute of Power Electronics
    • /
    • v.5 no.4
    • /
    • pp.377-385
    • /
    • 2000
  • This paper presents the test and operation results of the domestic demonstration of the reactive power compensation device called STATCOM (STATic COMpensator). The object of the paper is to describe the reliability of the unit based on the extensive operation databases. The custom power is similar in nature to the concept of FACTS(Flexibel AC Transmission System). By controlling reactive power, the technology offers utilities the opportunity for increased efficiency and their capabilities will permit transmission planners make the best use of their existing transmission resources. STATCOM is a custom power device in a way and can be used in a similar way for the dynamic compensation of power transmission systems, providing reactive power compensation, voltage regulation and mitigation of voltage flicker. It is shown that the STATCOM has clear advantages in areas such as; providing reactive power compensation and improving power factor.

  • PDF

A Study on Reactive Current Compensation Using Thyristor Switch (Thyristor Switch를 사용한 무효전류 보상에 관한 연구)

  • 박민호;이복용
    • 전기의세계
    • /
    • v.28 no.12
    • /
    • pp.41-45
    • /
    • 1979
  • Improvement of power factor is achieved by reactive-current compensation, connecting power condenser to the circuit. This paper describes a method of reactive-current compensation, employing thyristor switching of capacitor banks without any breaker. This method reduces supply transients to the minimum by means of connecting condenser, because thyristor is triggered at zero point in condenser current. The reactive current detection and the experimental system to trigger thyristor at appropriate moment are given. IThe results show the fast reactive-current compensation on the condition of minimum transient.

  • PDF

Reactive Power Compensator for Pulsed Power Electric Network of International Thermonuclear Experimental Reactor (국제 열핵융합실험로 펄스전원계통의 무효전력보상기 검증)

  • Jo, Hyunsik;Jo, Jongmin;Cha, Hanju
    • The Transactions of the Korean Institute of Power Electronics
    • /
    • v.20 no.3
    • /
    • pp.290-295
    • /
    • 2015
  • Analysis and verification of reactive power compensator (RPC) for ITER pulsed power electric network (PPEN) are described in this paper. The RPC system is rated for a nominal power of 250 Mvar necessary to comply with the allowable reactive power limit value from the grid 200 Mvar. This system is currently under construction and is based on static var compensation technology with a thyristor-controlled reactor and a harmonic filter. The RPC minimizes reactive power from grid using prediction of reactive power consumption of AC-DC converters. The feasibility of the reactive power compensation was verified by assembling a real controller and implementing ITER PPEN in the real time digital simulator for the hardware-in-loop facility. When maximum reactive power is reached, grid voltage is stabilized and maximum reactive power decreased from 120 Mvar to 40 Mvar via the reactive power prediction method.

A Hybrid Static Compensator for Dynamic Reactive Power Compensation and Harmonic Suppression

  • Yang, Jia-qiang;Yang, Lei;Su, Zi-peng
    • Journal of Power Electronics
    • /
    • v.17 no.3
    • /
    • pp.798-810
    • /
    • 2017
  • This paper presents a combined system of a small-capacity inverter and multigroup delta-connected thyristor switched capacitors (TSCs). The system is referred to as a hybrid static compensator (HSC) and has the functions of dynamic reactive power compensation and harmonic suppression. In the proposed topology, the load reactive power is mainly compensated by the TSCs. Meanwhile the inverter is meant to cooperate with TSCs to achieve continuous reactive power compensation, and to filter the harmonics generated by nonlinear loads and the TSCs. First, the structure and mathematical model of the HSC are discussed Then the control method of the HSC is presented. An improved reduced order generalized integrator (ROGI)-based selective current control method is adopted in the inverter to achieve high-performance reactive and harmonic current compensation. Meanwhile, a switch control strategy is proposed to implement precise and fast switching of the TSCs and to avoid changing the time delay needed by the conventional switch strategy. Experiments are implemented on a 20 KVA HSC prototype and the obtained results verify the validity of the proposed HSC system.

Determining the Reference Voltage of 345 kV Transmission System Considering Economic Dispatch of Reactive Power (무효전력 경제급전을 고려한 345㎸ 송전계통의 기준 전압 설정 방법)

  • Hwang, In-Kyu;Jin, Young-Gyu;Yoon, Yong-Tae;Choo, Jin-Boo
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.67 no.5
    • /
    • pp.611-616
    • /
    • 2018
  • In the cost based pool market in Korea, there is no compensation of reactive power because the fuel cost for reactive power is relatively low compared to that of active power. However, the change of energy paradigm in the future, such as widespread integration of distributed renewable energy source, will prevent the system operator from mandating the reactive power supply without any compensation. Thus, in this study, we propose the reference voltage of the 345 kV transmission system that minimizes the reactive power supply. This is closely related to the economic dispatch of reactive power aiming at minimizing the compensation cost for the reactive power service. In order to verify the effectiveness of the proposed reference voltage, the simulations are performed using the IEEE 14 bus system and the KEPCO real networks. The simulation results show that a voltage lower than the current reference value is recommended to reduce the reactive power supply and also suggest that the current voltage specification for the 345 kV system needs to be reviewed.

Study on Optimized Scheme of Reactive Power Compensation for Low Short-Circuit-Ratio HVDC System (저단락비 HVDC 시스템에서웨 무효편력수급 최적 방안 연구)

  • Baek Seung-Taek;Han Byung-Moon;Oh Sea-Seung;Jang Gil-Soo
    • The Transactions of the Korean Institute of Electrical Engineers A
    • /
    • v.54 no.9
    • /
    • pp.434-440
    • /
    • 2005
  • This paper describes an optimized Scheme of reactive-power compensation for the low short-circuit-ratio AC system interconnected with the HVDC system. An HVDC system interconnected with tile low SCR AC system is vulnerable to the ac voltage variation, which brings about the commutation failure of the converter. This problem can be solved using optimized compensation of reactive power. In this study, a benchmark system for HVDC system interconnected with low SCR AC system is derived using PSS/E simulation. Then an optimized srheme for reactive power compensation was derived using integer programming. The feasibility of proposed scheme was analyzed through silnulations with PSS/E and PSCAD/EMTDC. The proposed scheme can compensate the reactive power accurately and minimize the number of switching for harmonic filters and shunt reactors.

A Study on the Operation Characteristics of a Reactive Power Copensator using PWM Converter (PWM 콘버어터를 이용한 순시무효전력 보상장치의 동작해석)

  • Kwon, Ki-Hyun;Kwon, Soon-Jae;Kim, Cheul-U;Whang, Yong-Moon
    • Proceedings of the KIEE Conference
    • /
    • 1989.11a
    • /
    • pp.310-312
    • /
    • 1989
  • From the viewpoint of an effective energy use, many method for reactive power compensation has been developed. Among of the reactive power compensation, this paper describes the relation of operation interpretation, filter, hysteresis width and switching time of current controlled PWM converter which has excellent reactive power compensation. This current controlled PWM convertor is excellent the view of reactive power compensation by current control method using hysteresis comparator method, but is required element of high response characteristics. Therefore this paper offers the series of data for system considering switching characteristics of switching element.

  • PDF

Instantaneous Active/Reactive Power Compensation of Distribution Static Compensator using State Observer (배전용 정지형 보상기의 상태관측기를 이용한 순시 유효/무효전력 보상)

  • Kim, Hyeong-Su;Choi, Jong-Woo
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.57 no.8
    • /
    • pp.1377-1382
    • /
    • 2008
  • DSTATCOM(distribution static compensator) is one of the custom power devices, and protects a distribution line from unbalanced and harmonic current caused by non-linear and unbalanced loads. Researches about DSTATCOM are mainly divided two parts, one is the calculation of compensation current and the other part is the current control. Conventional researches use a LPF(low pass filter) to eliminate ripple component at the calculation of compensation current. But this method has a problem that LPF's characteristics restrict the compensation performance of instantaneous active and reactive power. This paper proposes a calculation of compensation current using state observer that can be a counterproposal of conventional methods using LPF. Improved performance of instantaneous active and reactive power compensation was shown by experiments.