Analysis on Unbalance Protection of SCB

2013 ◽  
Vol 341-342 ◽  
pp. 1423-1428
Author(s):  
Xiao Ping Xiong ◽  
Jing Jie Hu ◽  
Qiang Fu

Shunt capacitor is a main measure to reactive power compensation of power system, which has the advantages of flexibility and economy. In order to guarantee the safety of shunt capacitor, the methods for protecting against over-voltage, under-voltage, over-current and unbalance in circuits according to the different operation modes are used. This paper in detail introduces unbalance protection ways under different connection modes of capacitor group. It is analyzed and calculated that the unbalanced current and voltage with the effects of fault capacitor units, components and fuses on capacitor bank as well through a case of unbalance computation of shunt capacitor banks (SCB) of ungrounded single star with external fuse. It is indicated by PSCAD simulation analysis that the result of theory calculation is the same as the simulation, which provides theory basis of setting the tripping point and alarm point of relay protection.

2013 ◽  
Vol 694-697 ◽  
pp. 846-849
Author(s):  
Jian Yuan Xu ◽  
Wei Fu Qi ◽  
Yun Teng

This paper mainly studies wind power fluctuations how to affect voltage stability after the wind power grid integration, and reactive power compensation equipment on improving effect. In certain parts of the wind farm, for example, firstly, analyzing the wind farm reactive power problems. Then introduce the reactive power compensation equipment that used in the wind farm. Finally, with PSCAD software, making a simulation analysis about the influence on the power grid voltage according to adopting the different reactive power compensation devices or not.


2012 ◽  
Vol 608-609 ◽  
pp. 1151-1155 ◽  
Author(s):  
Xiao Hua Yuan ◽  
Xian Bin Dai

The alternator output power in the power system can be divided into active and reactive power. The active power (in kW) is that part of the electrical energy for doing work and heat loss, such as the conversion of mechanical energy, heat, light. The reactive power (in kVar) is that part of the electrical energy for the exchange of electric and magnetic fields in the circuit, such as transformers, motors, through the magnetic field can be passed to convert electrical energy; transmission lines in cable systems and a variety of load reactance (inductance and capacitance), and consumption of reactive power. With the rapid development of power system to study how to reduce energy loss in the power system is a very meaningful. In this paper, The Shizuishan plant desulfurization project as an example, illustrates the shunt capacitor reactive power compensation of the power system energy saving.


2018 ◽  
Vol 7 (1.8) ◽  
pp. 188
Author(s):  
M Dhana Sai Sri ◽  
P Srinivasa Varma

Reliability of network is need of the hour in the present power system market and is constrained by capability of the network. The network calculations are performed using accurate and high efficient strategies. In order to perform power transactions in the system, the computation of available transfer capability is essential which a metric of capability of the system. Generally, effect wattless power is not taken into account in the methodologies for computation of linear available transfer capability. In this paper, a methodology which considers the reactive power flows for enhancement of linear ATC is presented. In order to perform analysis theoretically, a standard IEEE 3 bus system is considered. Another case study i.e., 14 bus system available in IEEE test systems is used for simulation analysis. FACTS technology is incorporated in the existing system in order to enhance capability of the network. To facilitate transfer maximum power in the system, an optimal power-flow-based ATC enhancement model is formulated and presented along with simulation results. Studies based on the IEEE 3-bus system and 14-bus systems with TCSC demonstrate the effectiveness of FACTS control on ATC enhancement.  


Vestnik MEI ◽  
2021 ◽  
Vol 3 (3) ◽  
pp. 11-18
Author(s):  
Nailia Sh. Chemborisova ◽  
◽  
Ivan D. Chernenkov ◽  

The problem of selecting the electric power system control nodes is studied. By performing control of these modes, matters concerned with providing reliable power supply of the required quality to consumers can be settled in the most efficient manner. As an example, a fragment of the electric power system mathematical model used in the Finist mode-setting simulator for a power system dispatch control center operator is considered, which represents a highly branched electrical network consisting of eleven 110 kV nodes, three 220 kV nodes connected with the system, and two generator nodes. A new procedure for selecting the control nodes is proposed, which takes into account a combination of different indicators having different measurement units, dimensions and scales is proposed. These indicators characterize the following properties of power system nodes: the reactive power fraction absorbed at a node, the sensitivity of voltage to reactive load variations, the number of connected power lines, and statistical indicators characterizing the change of voltage at the nodes and reactive power flows for different options of installing the reactive power compensation devices. For combined use of these indicators, they were ranked according to the efficiency of installing reactive power compensation devices in the system. For each indicator, a scale of five ranks (intervals) is set, which determine the preferences (qualitative judgments) of the researcher in evaluating the reactive power compensation devices installation efficiency at the system nodes. The highest rank (5) corresponds to the maximum efficiency, and the lowest rank (1) corresponds to the minimum efficiency. To calculate the individual (integral) priority indicator of installing reactive power compensation devices, the ranks of indicators are added together, and their sum is divided by the product of the number of ranks by the number of the used indicators (features). Based on the calculation results, the rating (location) of each node is determined, and the nodes for installing the reactive power compensation devices are selected according to their effect on ensuring the electric power system operation reliability, active power losses in the network, and voltage regulation. Thus, a new procedure is presented for determining the integral indicators for comprehensively estimating the properties of complex electric power system nodes and selecting the controlled nodes using a system of various indicators. These indicators characterize the studied nodes in terms of the efficiency of installing reactive power compensation devices to reduce active power losses in the network, voltage regulation, and ensuring the electric power system operational reliability. The validity of the results obtained in the study is confirmed by their comparison with the indicators of the balance-conductivity method, which has proven itself in solving problems connected with determining the nodes for controlling electric power system operation modes.


Author(s):  
Jialin Li ◽  
Honggang Ding ◽  
Ye Sun ◽  
Jingming Guo ◽  
Jiapeng Wang ◽  
...  

2018 ◽  
Vol 7 (3.31) ◽  
pp. 36
Author(s):  
Srikanth B. Venkata ◽  
Lakshmi Devi Ai

This paper deals with the identification of instability nodes of IEEE 30 BUS power system to generation removal. Optimal sizing and locations of reactive power compensations are obtained. Firstly one of the generators is assumed to be removed from service and the saddle node bifurcation (SNB) point voltages are evaluated without reactive power compensation. Secondly two generators are assumed to be removed from service and the saddle node point voltage magnitudes are obtained without reactive power compensation. For both cases the study is conducted by placing optimal reactive power compensations at optimal locations using Bacterial Foraging Optimization Algorithm (BFOA).  


Sign in / Sign up

Export Citation Format

Share Document