Effect of the asymmetry of currents and voltages on the precision of reactive power and energy measurements

1965 ◽  
Vol 8 (4) ◽  
pp. 340-343
Author(s):  
A. M. Ilyukovich
Keyword(s):  
Reactive Power ◽  
The Asymmetry ◽  
Power And Energy

A simple network reduction technique for large autonomous microgrids incorporating an efficient reactive power sharing

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Anitha Daniel ◽  
Suchitra Dayalan
Keyword(s):  
Reactive Power ◽  
Reduction Technique ◽  
Power Sharing ◽  
Local Loads ◽  
Effective Power ◽  
Matlab Simulink ◽  
Network Reduction ◽  
Feasible Method ◽  
The Asymmetry ◽  
Simple Network

Abstract Reactive power sharing continues to be a challenge for an autonomous Microgrid (MG) since reactive power sharing is largely affected by the mismatch in line impedance and the asymmetry of local loads. Several reactive power sharing methods have been proposed in an autonomous MG but their effectiveness on large MG systems has not been explored much. This paper considers a standard IEEE 38 bus autonomous MG to study the effectiveness of proportionate power sharing. A simple network reduction technique has been proposed to obtain an equivalent reduced MG for which a reactive power sharing technique is applied. The most feasible method has been analyzed and the communication based reactive power sharing along with droop controller is proved to be the popular and most generalized strategy for effective power sharing. MATLAB-Simulink tool is used to validate the power sharing with equal and unequal DG ratings in a standard IEEE 38 bus autonomous MG system with network reduction.

scholarly journals The influence of the network asymmetry on the settings and sensitivity of an earth fault protection using higher harmonics

2019 ◽  
Vol 84 ◽  
pp. 02008
Author(s):  
Lubomir Marciniak ◽  
Mateusz Piątek
Keyword(s):  
Reactive Power ◽  
Higher Harmonics ◽  
Medium Voltage ◽  
Earth Fault ◽  
Power Setting ◽  
Zero Sequence ◽  
The Asymmetry ◽  
Supply Voltages ◽  
Zero Sequence Voltage

Detection of high resistance earth faults in medium voltage networks is an important problem due to ineffectiveness of traditional earth fault protections. Such short circuits can be detected by the criterion of a reactive power of higher harmonics for zero sequence current and voltage. The main problem is determination of the power setting value in the protection, which depends on the asymmetry of phase-to-earth capacitances and higher harmonics in supply voltages, which are generated by non-linear loads. The intensive tests of the asymmetry of the zero sequence currents and voltages for harmonics and their reactive power have been carried out in 15 kV compensated network as a function of all relevant parameters, i.e.: maximum capacitance deviation of the network and protected line, percentage content of harmonics in supply voltages, capacitive current of the network and the line. It has been shown that third harmonics of the zero sequence voltage and current are the best suited for practical use, since the asymmetry reactive power of these components is the smallest among the considered harmonics and the protection sensitivity will be the highest.

scholarly journals Optimization of the power consumption mode of pumping stations of “Suv Okova” by reactive power

2021 ◽  
Vol 264 ◽  
pp. 04089
Author(s):  
Shavkat Muzafarov ◽  
Abdusaid Isakov ◽  
Ruzimurat Choriev ◽  
Zukhra Ismailova ◽  
Durdona Mustafoyeva
Keyword(s):  
Reactive Power ◽  
Optimality Criteria ◽  
Operating Conditions ◽  
Absolute Minimum ◽  
Unconstrained Optimization Problem ◽  
Pumping Stations ◽  
Mode Of Operation ◽  
Nonlinear Form ◽  
Compensating Devices ◽  
Power And Energy

The optimal modes of the existing compensating devices under operating conditions were determined. Minimum power and energy losses were taken as optimality criteria. The unconstrained optimization problem was considered, i.e., finding the absolute minimum. When solving the problem to find the optimal mode of operation of the “SUV OKOVA” network, a relative minimum was found since the system of constraints has a nonlinear form. The problem of conditional optimization in terms of reactive power is solved, for which the gradient method of quadratic programming is used.

New method for reactive power and energy measurement

1992 ◽  
Vol 41 (2) ◽  
pp. 280-285 ◽  
Author(s):  
B. Djokic ◽  
P. Bosnjakovic ◽  
M. Begovic
Keyword(s):  
Reactive Power ◽  
New Method ◽  
Energy Measurement ◽  
Power And Energy
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