A Intergrated Compensation Device Design for Three-Phase Unbalance and Reactive Power of Low Line

2013 ◽  
Vol 706-708 ◽  
pp. 601-608
Author(s):  
Hai Xiang Wang ◽  
Wei Peng Zhou ◽  
A Fang Hang
Keyword(s):  
Low Power ◽  
Power Factor ◽  
Reactive Power ◽  
Software Process ◽  
Frequency Detection ◽  
Thyristor Switch ◽  
Three Phase ◽  
Detection Circuit ◽  
Compensation Device ◽  
Switch Circuit

The harm of high three-phase unbalance factor and low power factor is introduced. The design of hardware and software process is given. The design of AD circuit , adjust circuit , frequency detection circuit and thyristor switch circuit is illustrated.

scholarly journals Three Phase Enhanced Electrical Energy Metering System

2020 ◽  
Vol 16 ◽  
Keyword(s):  
Low Power ◽  
Power Factor ◽  
Reactive Power ◽  
Electrical Energy ◽  
Human Errors ◽  
Existing Problems ◽  
Control Units ◽  
Three Phase ◽  
Energy Metering ◽  
Core Losses

This paper presents a practical solution for two existing problems in traditional electrical energy measurements. The first problem is the manual electrical billing system; so far, some countries are still adopting a manual technique with a high percentage of human errors and much complains from the consumers’ side and a lot of work from the authorities’ side. The second problem is having a low power factor at most of the domestic loads and some main commercial ones. Low power factor causes more current to flow in the network leading to an overheating of transformers and cables, and an increase of the core losses of transformers; in addition, less power factor means more burned fuel and more environment pollution. In This study, an automated solution for both problems is introduced, where two control units are added to the already existing three phase energy meters. The first unit solves the problem of manual billing by automatically calculating the monthly bill and sending monthly SMS messages to the consumers as well as authorities. The second unit solves the problem of low power factor by injecting reactive power using capacitor bank at the end load points to maintain a power factor of 0.95 at all load cases. A penalty will be added to the monthly calculated bill once the above value is violated. A prototype was implemented proving the capability of introducing both solutions using existing meters with a reasonable added cost

Reactive Power Compensation for Unbalanced Fluctuating Loads by Using Two-Dimensional Space Vector and a Static Var Compensator

2014 ◽  
Vol 533 ◽  
pp. 397-400 ◽  
Author(s):  
Chi Jui Wu ◽  
Yu Wei Liu ◽  
Shou Chien Huang
Keyword(s):  
Power Factor ◽  
Reactive Power ◽  
Dimensional Space ◽  
Measurement Data ◽  
Power Source ◽  
Active Power ◽  
Two Dimensional ◽  
Static Var Compensator ◽  
Space Vector ◽  
Three Phase

To modify the power factor and balance the three-phase currents simultaneously, this paper proposes the instantaneous compensator to calculate the compensation current. The instantaneous compensator utilizes two-dimensional instantaneous space vector and setting the active power as a constant for each cycle which can improve power quality effectively. Moreover, the instantaneous compensator requires an independent power source, whose capacity can be reduce by using a static var compensator (SVC). An SVC does not interfere with the capability of the instantaneous compensator. Field measurement data were analyzed. Simulation results confirmed the feasibility of correcting the power factor and balancing load currents simultaneously using the proposed method.

scholarly journals Decoupled Control of Three Phase Grid Connected Solar PV System

2019 ◽  
Vol 9 (2) ◽  
pp. 4218-4222
Keyword(s):  
Solar Energy ◽  
Power Factor ◽  
Control Strategy ◽  
Reactive Power ◽  
Standard Test ◽  
Effective Control ◽  
Solar Pv ◽  
Pv System ◽  
Three Phase ◽  
Decoupled Control

A reliable grid connected Photovoltaic (PV) system require effective control schemes for efficient use of solar energy. This paper presents a three-phase grid tied PV system with decoupled real and reactive power control to achieve desired power factor with Maximum Power Point Tracking (MPPT) controller to get maximum solar energy. The synchronous reference frame (dq) control along with decoupling concept is used to control the DC-AC inverter output, while the Phase Locked Loop (PLL) synchronization technique is used to monitor and synchronize the voltage and current at the grid side. The DC-DC converter with Incremental Conductance (InC) based MPPT model is also designed in this paper due to better accuracy compared to Perturb & Observe (P&O) algorithm. The simulation is performed in MATLAB/SIMULINK and a 31.5 kW PV system is modelled to get 30 kW power with the help of MPPT at Standard Test Conditions (STC). Any power factor value between 0.85 lagging to 0.9 leading can be obtained by changingreference q current in this inverter control strategy. The simulation results show that the change of reactive powerdoes not affecttheactive power values of the system, which verifies the effectiveness of the decoupled control strategy of the inverter.

scholarly journals Design and Simulation of three Phase three Wire Shunt Active Filter using Instantaneous PQ Theory

2020 ◽  
Vol 15 (1) ◽  
pp. 181-186
Author(s):  
Tilak Giri ◽  
Ram Prasad Pandey ◽  
Sabin Bhandari ◽  
Sujan Moktan ◽  
Lagat Karki
Keyword(s):  
Power Factor ◽  
Communication Systems ◽  
Reactive Power ◽  
Active Filter ◽  
Shunt Active Filter ◽  
Current Harmonics ◽  
Passive Filter ◽  
Three Phase ◽  
Wide Range ◽  
Source Current

Due to intensive use of power converters and other non-linear loads, power quality is degrading. The presence of harmonics in the power lines result in greater power losses in distribution, interference problems in communication systems. Non linearity reduces the efficiency and power factor of the system. As the power factor reduces, the reactive power demanded from the supply increases which have no any contribution in energy transfer, so compensation is required. For this, shunt passive filter has been developed but it is bulky and frequency dependent and has many drawbacks. In contrast to passive filter, shunt active filter (SAF) has been developed which is smaller and has wide range of applications. In this paper, shunt active filter based on p-q theory is demonstrated for compensating reactive power and current harmonics. Simulation has been done with and without SAF and results are presented and ended with recommendation and conclusion. An effort is made to reduce the THD of the source current below 5% (specified by IEEE).

The Research of the New High Voltage Reactive Power Compensation Device Based on the Compound Switch

2014 ◽  
Vol 496-500 ◽  
pp. 1097-1100 ◽  
Author(s):  
Yin Sheng Wang ◽  
Xue Di Qiao
Keyword(s):  
Reactive Power ◽  
Power Grid ◽  
Reactive Power Compensation ◽  
Parallel Capacitor ◽  
Thyristor Switch ◽  
Compensation Device ◽  
Equipment Utilization ◽  
Contact Switch ◽  
Current Zero ◽  
The Impact

With the increase of power system load, the demand for reactive power is also increasing. In order to ensure the power quality and improve equipment utilization, transmission of reactive power in power grid can lead to network loss and the voltage of the electricity. Installing reactive power compensation device in power grid is the essential means to meet the demand of power grid reactive power [1].The parallel capacitor reactive power compensation device is equipped in the coal mine 3.3 kV system reactive power compensation [2]. Introducing the parallel capacitor reactive power compensation principle and related problems, analysis of the current commonly uses contactor, relay and thyristor switch device, chooses the contactor and breaks pipe parallel composite switch which can have contact and non-contact switch to solve their problems [3]. Using software EMTP simulation composite switch voltage zero input, the result is very good to restrain the impact flow; Compound switch off after current zero avoids the contactor breaking arc, the simulation thyristor compound switch and diode in parallel.

scholarly journals Voltage Unbalance, Power Factor and Losses Optimization in Electrified Railways Using an Electronic Balancer

Electricity ◽  
2021 ◽  
Vol 2 (4) ◽  
pp. 554-572
Author(s):  
António P. Martins ◽  
Pedro Rodrigues ◽  
Mahmoud Hassan ◽  
Vítor A. Morais
Keyword(s):  
Low Power ◽  
Power Factor ◽  
Electric Energy ◽  
Field Measurements ◽  
Electric Grid ◽  
Voltage Unbalance ◽  
Three Phase ◽  
Railway System ◽  
Regenerative Energy ◽  
Electrified Railways

Unbalanced currents, low power factor and high losses contribute to increasing the bill infrastructure managers must pay to the TSO/DSO operator that supplies electric energy to the railway system. Additionally, if regenerative energy coming from braking regimes is not allowed to be injected into the grid or even is penalized when it occurs, then the optimization of those parameters must be pursued. One of the possible measures that can be taken to counteract those phenomena is the installation of electronic balancers in heavy loaded substations in order to optimize the interface to the three-phase electric grid. This paper shows the benefit of such use taking examples from real conditions and realistic simulations assumed equivalent to field measurements.

Vector Decoupling Control Strategy for Three-Phase Voltage Source PWM Rectifier

2013 ◽  
Vol 336-338 ◽  
pp. 450-453
Author(s):  
Jian Ying Li ◽  
Wei Dong Yang ◽  
Ni Na Ma
Keyword(s):  
Power Factor ◽  
Control Strategy ◽  
Reactive Power ◽  
Decoupling Control ◽  
Voltage Source ◽  
Pwm Rectifier ◽  
Phase Voltage ◽  
Unity Power Factor ◽  
Three Phase ◽  
Rotating Coordinates

In view of the fact that active power and reactive power have coupling relation, a novel vector decoupling control strategy is presented for three-phase voltage source PWM rectifier. In the paper, the power control mathematical mode of the PWM rectifier is deduced based on the mathematical model of rectifier in synchronous d-q rotating coordinates, and a new voltage feed forward decoupling compensation control strategy is proposed. The simulation results show that the voltage and current of the three-phase PWM rectifier have better respond preference, the current aberrance is smaller and the voltage is steady under the control strategy. The PWM rectifier can implement PWM commute with unity power factor, but also feed back the energy to AC side with unity power factor.

Simulation Study of Harmonics and Reactive Power in Three-Phase Full-Bridge Controlled Rectifier Circuit with Resistance-Inductance Load

2011 ◽  
Vol 383-390 ◽  
pp. 621-626
Author(s):  
Yu Fei Wang ◽  
Chang Hui Yang ◽  
Hua Xue ◽  
Xiu Yang
Keyword(s):  
Power Factor ◽  
Simulation Study ◽  
Reactive Power ◽  
Simulation Analysis ◽  
Electronic Devices ◽  
Power Electronic ◽  
Specific Design ◽  
Matlab Simulink ◽  
Rectifier Circuit ◽  
Three Phase

In order to evaluate the harm and impact of power electronic devices on the grid and provide numerical basis for specific design of the corresponding compensated devices, the harmonics and reactive power of three-phase full-bridge controlled rectifier circuit with resistance-inductance load are studied in this paper. Firstly, the harmonics and power factor of the ac side current are analyzed theoretically; the harmonics contents and power factor are calculated. Secondly, the model of three-phase full-bridge controlled rectifier circuit is built in Matlab/Simulink, and the simulation analysis of the ac side power factor and harmonics is achieved, the simulated values are similar to the theoretical values. The results show that the complex calculations of harmonics and power factor can be completed simply and intuitively using simulation study, the simulation study is efficient and accurate.

scholarly journals Improved Control Strategy for Three-Phase Microgrid Management with Electric Vehicles Using Multi Objective Optimization Algorithm

Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 1146
Author(s):  
Muhammad Shahab ◽  
Shaorong Wang ◽  
Abdul Khalique Junejo
Keyword(s):  
Low Power ◽  
Electric Vehicles ◽  
Power Factor ◽  
Control Strategy ◽  
Ancillary Services ◽  
Dynamic Programming Method ◽  
High Peak Power ◽  
Multi Objective Optimization ◽  
Multi Objective ◽  
Three Phase

The usage of electric vehicles (EV) have been spreading worldwide, not only as an alternative to achieve a low-carbon future but also to provide ancillary services to improve the power system reliability. A common problem encountered in the existing alternating current (AC) grids is low power factor, which cause several power quality problems and has worsened with the growing application of distributed generation (DG). Therefore, considering the spread of EVs usage for ancillary services and the low power factor issue in current electrical grids, this paper proposes an improved control strategy for power factor correction of a three-phase microgrid management composed of a photovoltaic (PV) array, dynamic loads, and an EV parking lot. This control strategy aims to support power factor issues using the EV charging stations, allowing the full PV generation. Different operation modes are proposed to fulfill the microgrid and the EV users’ requirements, characterizing a Multi Objective Optimization (MOO) approach. In order to achieve these optimization requests, a dynamic programming method is used to charge the vehicle while adjusting the microgrid power factor. The proposed control algorithm is verified in different scenarios, and its results indicate a suitable performance for the microgrid even during conditions of overload and high peak power surplus in generation unit. The microgrid power factor remains above the desired reference during the entire analyzed period, in which the error is approximately 4.5 less than the system without vehicles, as well as obtains an energy price reduction.

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