A New Hybrid Power Conditioner for Suppressing Harmonics and Neutral-Line Current in Three-Phase Four-Wire Distribution Power Systems

The article considers a hybrid power quality conditioner (HQPC) for 3-phase 4-wire systems with a distributed modular structure. Some conditioner modules provide compensation for the component currents and voltages that form the negative and zero sequence systems. The open structure of the HQPC, consisting of independent modules, allows compensating for distortions of currents and voltages of the 3-phase network caused by the nonlinear nature and asymmetry of single-phase loads. The compensation characteristics of the proposed conditioner were researched using a model developed in the MatLab environment. The simulation showed that the proposed conditioner can ensure normalization of power quality in 3-phase 4-wire system at various modes of network operation.

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A model-based controller for a three-phase four-wire shunt active filter with compensation of the neutral line current

2006 IEEE International Power Electronics Congress ◽

10.1109/ciep.2006.312127 ◽

2006 ◽

Cited By ~ 2

Author(s):

A. A. Valdez ◽

G. Escobar ◽

R. E. Torres-olguin ◽

M. F. Martinez-montejano

Keyword(s):

Neutral Line ◽

Active Filter ◽

Shunt Active Filter ◽

Line Current ◽

Model Based ◽

Three Phase

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Detecting High Impedance Faults Utilizing Combined Phase Voltages with Neutral Line Current

International Journal of Emerging Electric Power Systems ◽

10.2202/1553-779x.1036 ◽

2005 ◽

Vol 2 (2) ◽

Cited By ~ 3

Author(s):

Ming-Ta Yang ◽

Jhy-Cherng Gu

Keyword(s):

Neutral Line ◽

Discrete Wavelet ◽

New Approach ◽

Line Current ◽

High Impedance ◽

Three Phase ◽

Input Signals ◽

Distribution Feeder ◽

High Impedance Faults ◽

Distinct Features

This study aims to present a new approach to detecting high impedance faults (HIFs) in the distribution feeder. Discrete wavelet transformations (DWT) and neural networks (NN) have been widely applied in power system research. Consequently, this study developed a novel technique to discriminate effectively between the HIFs and the switch operations by combining DWT with NN. The proposed approach has three distinct features. First, the input signal of this algorithm is neutral line current, rather than the conventional currents based on three individual phases. Second, HIFs identification uses the details at levels 3, 4 and 5 and the approximations at level 5 of the neutral line current are utilized for. Third, the input signals of the three-phase voltages classify the faulty and healthy phases. The results of simulation and field staged fault clearly show that the proposed technique can accurately identify the HIFs in the distribution feeder.

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THE ANALYSIS OF OPERATION MODES OF ENERGY STORES IN AUTONOMOUS HYBRID POWER PLANTS WITH RENEWABLE ENERGY RESOURCES

Alternative Energy and Ecology (ISJAEE) ◽

10.15518/isjaee.2018.13-15.055-067 ◽

2018 ◽

pp. 55-67

Author(s):

S. G. Obukhov ◽

I. A. Plotnikov ◽

V. G. Masolov

Keyword(s):

Renewable Energy ◽

Power Systems ◽

Low Frequency ◽

Rechargeable Batteries ◽

Energy Resources ◽

Renewable Energy Resources ◽

Hybrid Power ◽

Operation Modes ◽

Energy Stores ◽

Energy Store

The paper presents the results of the comparative analysis of operation modes of an autonomous hybrid power complex with/without the energy store. We offere the technique which defines the power characteristics of the main components of a hybrid power complex: the consumers of the electric power, wind power and photo-electric installations (the last ones have been constructed). The paper establishes that, in order to compensate the seasonal fluctuations of power in autonomous power systems with renewable energy resources, the accumulative devices are required, with a capacity of tens of MWh including devices that are capable to provide energy storage with duration about half a year. This allows abandoning the storage devices for smoothing the seasonal fluctuations in the energy balance.The analysis of operation modes of energy stores has shown that for a stock and delivery of energy on time intervals, lasting several hours, the accumulative devices with rather high values of charging and digit power aren't required. It allows using the lead-acid rechargeable batteries of the deep category for smoothing the daily peaks of surplus and a capacity shortage. Moreover, the analysis of operation modes of energy stores as a part of the hybrid complexes has demonstrated that in charging/digit currents of the energy store the low-frequency and high-frequency pulsations of big amplitude caused by changes of size of output power of the renewable power installations and loading are inevitable. If low-frequency pulsations (the period of tens of minutes) can partially be damped due to the restriction of size of the maximum charging current of rechargeable batteries, then it is essentially impossible to eliminate high-frequency pulsations (the period of tens of seconds) in the power systems with the only store of energy. The paper finds out that the combined energy store having characteristics of the accumulator in the modes of receiving and delivery of power on daily time intervals, and at the same time having properties of the supercondenser in the modes of reception and return of impulses of power on second intervals of time is best suited to requirements of the autonomous power complexes with renewable energy resources.

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Reliability Index of Wind-Solar Hybrid Power Plants using the Expected Energy Not Supplied Method

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.d9733.118419 ◽

2019 ◽

Vol 8 (4) ◽

pp. 9449-9456

Keyword(s):

Power Plant ◽

Power Systems ◽

Electricity Market ◽

Reliability Index ◽

Power Plants ◽

Initial Conditions ◽

Hybrid Plant ◽

Total Power ◽

Hybrid Power ◽

Hybrid Power Plant

This paper proposes the reliability index of wind-solar hybrid power plants using the expected energy not supplied method. The location of this research is wind-solar hybrid power plants Pantai Baru, Bantul, Special Region of Yogyakarta, Indonesia. The method to determine the reliability of the power plant is the expected energy not supplied (EENS) method. This analysis used hybrid plant operational data in 2018. The results of the analysis have been done on the Pantai Baru hybrid power plant about reliability for electric power systems with EENS. The results of this study can be concluded that based on the load duration curve, loads have a load more than the operating kW of the system that is 99 kW. In contrast, the total power contained in the Pantai Baru hybrid power plant is 90 kW. This fact makes the system forced to release the load. The reliability index of the power system in the initial conditions, it produces an EENS value in 2018, resulting in a total value of 2,512% or 449 kW. The EENS value still does not meet the standards set by the National Electricity Market (NEM), which is <0.002% per year. Based on this data, it can be said that the reliability of the New Coast hybrid power generation system in 2018 is in the unreliable category.

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