• Title/Summary/Keyword: Reactive flow

Search Result 645, Processing Time 0.022 seconds

Improvement of the Power Flow Convergency Using Switched Shunt Reactive Power Sensitivity (Switched Shunt의 무효전력 민감도를 이용한 조류계산 수렴성 개선)

  • Oh, Sung-Kyun;Yang, Min-Yuk;Kim, Kern-Joong
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.61 no.3
    • /
    • pp.355-360
    • /
    • 2012
  • It is difficult to converge power flow for the power system planning data. The main cause of power flow diverse is reactive power imbalance. A active power could be adjust by ELD or merit order but a reactive power couldn't dispatch before power flow analysis. The lack of reactive power of power system is cause a inadequate voltage drop This paper suggest new reactive power dispatch algorithm using switched shunt admittance. This algorithm uses reactive power sensitivity called switch shunt jacobian. When proposed algorithm applies to real system data that couldn't be conversed in PSS/E the power flow analysis is converged.

Reactive Reserve based Contingency Constrained Optimal Power Flow to Enhance Interface Flow Limits in Terms of voltage Stability

  • Hwachang Song;Lee, Byongjun
    • KIEE International Transactions on Power Engineering
    • /
    • v.11A no.4
    • /
    • pp.27-32
    • /
    • 2001
  • This paper presents a concept of reactive reserve based contingency constrained optimal power flow (RCCOPF). RCCOPF for enhancement of interface flow limit is composed of two modules, which are the modified continuation power flow (MCPF) and reactive optimal power flow (ROPF). In RCCOPF, two modules are repeatedly performed to increase interface flow margins of selected contingent states until satisfying the required enhancement of interface flow limit. In numerical simulation, a simple example with New England 39-bus test system is shown.

  • PDF

Reactive Reserve based Contingency Constrained Optimal Power Flow to Enhance Interface Flow Limits in Terms of Voltage Stability

  • Hwachang Song;Lee, Byongjun
    • KIEE International Transactions on Power Engineering
    • /
    • v.11 no.X00
    • /
    • pp.27-32
    • /
    • 2001
  • This paper presents a concept of reactive reserve based contingency constrained optimal power flow (RCCOPF). RCCOPF for enhancement of interface flow limit is composed of two modules, which are the modified continuation power flow (MCPF) and reactive optimal power flow (ROPF). In RCCOPF, two modules are repeatedly performed to increase interface flow margins of selected contingent states until satisfying the required enhancement of interface flow limit. In numerical simulation, a simple example with New England 39-bus test system is shown.

A Method to Calculate Charge for Reactive Power Service under Competition of Electric Power Utilities

  • Ro, Kyoung-Soo;Park, Sung-Chul
    • KIEE International Transactions on Power Engineering
    • /
    • v.11A no.4
    • /
    • pp.39-44
    • /
    • 2001
  • As electric power systems have been moving from vertically integrated utilities to a deregulated environment, the charging of reactive power management is a new challenging them for market operators. This paper proposes a new methodology to compute the costs of providing reactive power management service in a competitive electrical power market. The proposed formulation, which is basically different from those shown in the literature, consists of two parts. One is to recover investment capital costs of reactive power supporting equipment based on a reactive power flow tracing algorithm. The other is to recover operational costs based on variable spot prices using the optimal power flow algorithm. The charging shapes resulted from the proposed approach exhibit a quite good meaning viewed from a practical sense. It turns out that reactive power charged are mostly due to recovery of capital costs and slightly due to recovery of operational costs. The methods can be useful in providing additional insight into power system operation and can be used to determined tariffs of a reactive power management service.

  • PDF

A Study on Efficient Calculation of Effective Reactive Power Reserves Using Sensitivity Analysis

  • Bae, Moonsung;Lee, Byongjun
    • Journal of Electrical Engineering and Technology
    • /
    • v.12 no.5
    • /
    • pp.1689-1696
    • /
    • 2017
  • In recent academic and industrial circles of the Republic of Korea, the securement of available reactive power reserve against the line faults is at issue. Thus, simulations have been performed for the securing of effective reactive power reserve (effective Q) to prepare for the line faults and improve reactive power monitoring and control methods. That is, a research has been conducted for the fast-decoupled Newton-Raphson method. In this study, a method that distinguishes source and sink regions to carry out faster provision of information in the event of line fault has been proposed. This method can perform quantification with the formula that calculates voltage variations in the line flow. The line flow and voltage changes can be easily induced by the power flow calculation performed every second in the operation system. It is expected that the proposed method will be able to contribute to securement of power system stability by securing efficient reactive power. Also, the proposed method will be able to contribute to prepare against contingencies effectively. It is not easy to prepare quickly for the situation where voltage drops rapidly due to the exhaustion of reactive power source by observing voltage information only. This paper's simulation was performed on the large scale Korean power system in steady state.

Development of Optimal Power Flow for the Ancillary Service of Reactive Power Generation under Restructuring Environment (전력산업 구조개편 환경 하에서 무효전력 보조서비스 운용을 위한 최적조류계산법 개발)

  • Lee, Seung-Ryeol;Lee, Byeong-Jun;Song, Tae-Yong;Jeong, Min-Hwa;Mun, Yeong-Hwan
    • The Transactions of the Korean Institute of Electrical Engineers A
    • /
    • v.51 no.1
    • /
    • pp.37-44
    • /
    • 2002
  • This Paper suggests reasonable pricing mathod fur Reactive Power in Optimal Power Flow for the system analysis. Under restructuring, not only real power pricing but also reactive power pricing is important for the system analysis and operation. If people just focus on real power pricing, the Generators may no generate reactive power voluntarily, because the Generators may not recover the cost of the reactive power generation. So making a reasonable reactive power pricing is becoming more important than any other time. In this paper, the authors set a Proper Power factor and price the portion of the reactive power that exceeds the power factor using Interior Point Method. By applying this method, the System operator can use this strategy for the analysis of reactive power generation pricing and the Generator can get the motivation to generate reactive power. The author develops fully optimized fast Primal Dual Interior Point Method with sparsity technique and applies this method to Reliability Test System (RTS24) and KEPCO 674 bus system (684 buses. 1279 lines). It shows adaptability and usefulness.

Reactive Reserve Based Contingency Constrained Optimal Power Flow for Enhancement of Voltage Stability Margins (전압안정도 여유 향상을 위한 무효예비력 기반 상정사고 제약 최적조류계산)

  • Song, Hwa-Chang;Lee, Byong-Jun;Kwon, Sae-Hyuk;Ajjarapu, Venkataramana
    • Proceedings of the KIEE Conference
    • /
    • 2003.07a
    • /
    • pp.19-23
    • /
    • 2003
  • This paper presents a new concept of reactive reserve based contingency constrained optimal power flow (RCCOPF) for voltage stability enhancement. This concept is based on the fact that increase in reactive reserves is effective for enhancement of voltage stability margins of post-contingent states, in this paper, the proposed algorithm is applied to voltage stability margin of interface flow. Interface flow limit, in the open access environment, can be a main drawback. RCCOPF for enhancement of interface flow margin is composed of two modules, modified continuation power flow (MCPF) and optimal power flow (OPF). These modules art recursively perform ed until satisfying the required margin of interface flow in the given voltage stability criteria.

  • PDF

Effects of Oxidizer Inject Angle on Combustion Characteristics in Hydro-Reactive Engine (Hydro-Reactive 엔진의 산화제 분사각도에 따른 연소특성에 대한 연구)

  • Won, Jong Han;Lee, Sung Nam;Baek, Seung Wook;Hwang, Chang Hwan;Kim, Kyung Moo
    • Journal of the Korean Society of Combustion
    • /
    • v.19 no.2
    • /
    • pp.1-7
    • /
    • 2014
  • In this study, the variation of the flow field in Hydro-reactive engine combustor was numerically studied through 2-dimensional axisymmetric model with aluminum and heated water vapor. For calculating all velocity fields, compressible Navier-Stokes equation was used with Pre-conditioning. AUSM+up(p) method was used to exactly calculate mass flow in the control volume. As using SST model that is a turbulent model, the result had high accuracy for free stream and the flow near the wall. The effects of the temperature, variation of the flow field and distribution of chemical products on inject angle of heated water vapor were studied.

A Study on Mechanical Properties of Reactive Powder Concrete Using copper slag (동제련 슬래그를 활용한 R.P.C.(Reactive Powder Concerete)의 역학적 특성에 관한 연구)

  • Lee, Yong-Moo;Shin, Sang-Yeop;Kim, Young-Soo
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2013.11a
    • /
    • pp.74-75
    • /
    • 2013
  • The paper study on the mechanical properties of reactive powder concrete using copper slag. A change in the replacement ratio s of copper slag was measured compressive strength and slump flow. As a results, slump flow using copper slag tend to increase slump flow with replacement ratio. As the concrete with a replacement ratio of copper slag up to 30% was found to have a compressive strength superior to that of plain.

  • PDF

A Method to Calculate a Service Charge for Reactive Power/Voltage Control under Competition of Power Utilities (전력시장 경쟁체제에서 무효전력/전압 제어 서비스의 가격책정 방법에 관한 연구)

  • Ro, Kyoung-Soo
    • Proceedings of the KIEE Conference
    • /
    • 2001.11b
    • /
    • pp.77-82
    • /
    • 2001
  • As electric power systems have been moving from vertically integrated utilities to a deregulated environment, the charging of reactive power management is a new challenging theme for market operators. This paper proposes a new methodology to compute the costs of providing reactive power management service in a competitive electrical power market. The proposed formulation, which is basically different from those shown in the literature, consists of two parts. One is to recover investment capital costs of reactive power supporting equipment based on a reactive power flow tracing algorithm. The other is to recover operational costs based on variable spot prices using the optimal power flow algorithm. The charging shapes resulted from the proposed approach exhibit a quite good meaning viewed from a practical sense. It turns out that reactive power charges are mostly due to recovery of capital costs and slightly due to recovery of operational costs. The method can be useful in providing additional insight into power system operation and can be used to determine tariffs of a reactive power management service.

  • PDF