Developing Algorithm and Program for Power Flow Analysis in Power System with STATCOM*

Keeping the voltage within the required limits is one of the key issues of operating a power system. since the voltage in electrical power system is affected significantly by changes of loads and equivalent circuit of the power system, there is a need to regulate the voltage with high control ability. Because of the growing use of FACTS in General and STATCOM among them in power systems to improve voltage stability, and because of the need for software that is not always available, the aim of research is to develop a mathematical model, algorithm and software for load flow analysis at the steady state of power system includes static synchronous compensator STATCOM. The Jacobian matrix in the Newton –Raphson algorithm, which is the relationship between voltage and power mismatches, is extended with the STATCOM variables to adjust the voltage and control of the reactive power witch is injected or absorbed at the point of common coupling, with high controlability. A Complete software has been developed that includes comprehensive control facilities and exhibits very strong convergence characteristics. A Sophisticated algorithm has been verified and the effectiveness of the program is tested by its application to a number of standard power systems including the IEEE 5-bus system, and Syrian transmission network 400 kV.

Impact of Reactive Compensators on Performance of Distance Protective Relays

This paper tries to clarify the impact of parallel and serial compensation of power transmission lines on the performance of distance relays which protect these lines. To this end, power system analysis software (NEPLAN) will be used for explaining distance relay behavior in the presence of different parallel or serial reactive power compensators, with main types of faults that may occur in different locations on the protected line. In this paper, Syrian power transmission network is simulated using (NEPLAN) software, and three reactive power compensators: parallel (STATCOM), serial (TCSC), and unified (UPFC), are used to compensate reactive power on transmission line. Several simulations, in many cases are carried out to illustrate the impact of fault type and location on the measured impedance seen by the distance relay. The objective of identifying the impact of reactive compensators on fault impedance seen by distance relay (i.e. fault location), is to determine the possible ways to resolve the problem and improve the performance of transmission line protection.

Developing Algorithm and Program for Power Flow Analysis in Power System with VSC-HVDC

with different frequency make Voltage Source Converter - HVDC link (VSC-HVDC links) an attractive technology for most power transport in meshed grids. Advantages are the high controllability of active and reactive power at the converter’s terminals and the ability to increase the stability of the surrounding AC system. VSC-HVDC can provide active and reactive control to achieve maximum power transfer, system stability and improve power quality and reliability. This research aims to develop a mathematical model and an algorithm for the analysis of power flow in a steady state of power system containing VSC-HVDC.The Jacobian matrix inNewton- Raphsonalgorithm, which is the relationship between voltage and power mismatches, is extended with the VSC HVDC variablesto control active and reactive powers and voltage magnitude in any combination. A Newton-Raphson load flow program has been developed which includes comprehensive control facilities and exhibits very strong convergence characteristics. Two scenarios have been studied, back-to-back VSC-HVDC link and full VSC-HVDC link connecting two buses in AC networks. The algorithm and the program have been verified through a number of simulation examples carried out on IEEE 14-bus System.

Developing Algorithm for Power Flow Analysis in Power System with UPFC aiming to Enhancing Voltage Profile and Loss Reduction

Unified Power Flow Controller (UPFC) plays a vital role in improving the power system performance, both the static and dynamic, and enhanced the system loading capability by rerouting the power flow in the network. This paper presents control and performance of UPFC intendedfor installation on the transmission line to control power flow and improve voltage profile.