Four wire single-phase to three-phase system for rural distribution network

Author(s):  
M.D. Bellar ◽  
M. Aredas ◽  
J.L.S. Neto ◽  
L.G.B. Rolim ◽  
Ud.A. Miranda ◽  
...  
2019 ◽  
Vol 16 (3) ◽  
pp. 289-310 ◽  
Author(s):  
Vinay Naguboina ◽  
Satish Gudey

In this work, a Three phase Transformerless Hybrid Series Active Power Filter (THSeAF) based on Sliding Mode Control (SMC) is proposed to mitigate the voltage and current distortions present in an electrical distribution systems (EDS). A Sliding Mode Controller is designed by controlling the parameters present on the load side as well as source side of the system. Three separate voltage source converters (VSC) are used. The mod1elling of the system is derived by considering a single-phase system by using state space analysis. The frequency response characteristics have been derived for the single-phase system and the stability of the system is studied. It is observed that the system has good stability margins when the SMC is applied at the source side compared to load side. Simulation results obtained in PSCAD/EMTDC v4.6 have been observed for power quality issues like voltage sags, voltage swells, voltage distortions, voltage unbalances and their concurrent occurrence. The approach of stationary reference frame was used for source side control and PQ theory is used for load side control. It is observed that the proposed controller works well in obtaining a stable and constant load voltage during these power quality issues. The difference in settling time observed is around 4 ms for the load side and source side control. The THD present in the load voltage is near about 1%. The SMC is found to be robust in obtaining a constant load voltage with low THD and an improved power factor.


Author(s):  
Alok Kumar Mishra ◽  
Soumya Ranjan Das ◽  
Prakash Kumar Ray ◽  
Ranjan Kumar Mallick ◽  
Himansu Das

Aims : The main focus in this work is to improve balanced and sinusoidal grid currents by feeding compensating current at point of common coupling (PCC). Background: In recent years the advancement in electronics and electrical appliances are widely improved and are also more sophisticated. These appliances require uninterrupted and quality power. Therefore in the growing power system scenario, several issues like malfunction of electrical sensitive devices, overheat in transformer, interference in communication, failures in computer network etc., adversely affects the power quality (PQ). These issues are generated due to rapid use of non-linear loads in three-phase system which generates harmonics in the system. To overcome from these PQ issues, several PQ mitigation custom power devices are integrated in power distribution network. But, the conventional PQ mitigation devices are insufficient to eliminate PQ problems such as current and voltage harmonics, voltage sag/swell and voltage unbalances associated with the power distribution network. Objective : The objective of using A-PSO is to find the global optimum of the spread factor parameter at the upper level. APSO, has a faster convergence speed and correct response compared to the PSO algorithm. Method : SO A-PSO M p-q. Result: A-PSO is giving better results than PSO. Conclusion : A three-phase system with SHAPF injected at PCC is proposed in this paper. The SHAPF injects filter current at PCC for supressing the harmonics using a modified pq scheme. For controlling the PIC, two optimised parameters are discussed and found that reducing the harmonics distortions using A-PSO is giving better results compare to the conventional PSO.


2021 ◽  
Vol 31 (08) ◽  
pp. 2150118
Author(s):  
Ali̇ Durdu ◽  
Yilmaz Uyaroğlu

In this study, a chaos-theoretic method is proposed to model the case of ferroresonance that can occur under nominal conditions in power systems, and the factors that determine the types of ferroresonance to occur are examined. In the ferroresonance chaotic system modeled in Matlab environment, the length of the transmission line and the breaker capacities in the circuit are fixed and its relationship with the transformer efficiency is investigated. In the proposed chaotic modeling, considering the situations that may occur in practical applications, the ferroresonance situations that occur when the single-phase remains open in the three-phase system are examined. In the study, ferroresonance, which occurs when one phase is open in a three-phase system, is analyzed by considering the situations that may happen during practical implementations. The similarity between the mathematical expressions obtained from the systems that create ferroresonance and Duffing oscillator is evaluated. In the chaotic system, fundamental ferroresonance, subharmonic ferroresonance, and chaotic ferroresonance situations are created depending on the transformer loss. Additionally, ferroresonance that occurs when the chaotic system is of fractional-order is analyzed, and it is observed that results of ferroresonance with different fractional-order values are not different. The results show that transformer loss is a significant element to determine the type of ferroresonance in power transformers. Also, when the chaotic system is operated in the fractional-order setting, the ferroresonance cases that occur are re-examined, and it is observed that the system can exit from the chaotic situation and prevent the formation of ferroresonance when fractional-order control is applied. According to the results, the fractional-order method can be used to control ferroresonance.


2014 ◽  
Vol 521 ◽  
pp. 288-291
Author(s):  
Yu Sheng Quan ◽  
Xin Zhao ◽  
Hua Gui Chen ◽  
En Ze Zhou

Based on the method of symmetrical components of D, 11 and Y, o distribution transformer coupling two different effects of different magnetic circuit coupled to the three-phase system with a system-generated analysis and comparison. Analysis of the difference between the two groups of different connections on the transformer structure. Described in the single-phase short circuit fault clearing, 3n harmonic current suppression and affordability aspects of single-phase unbalanced load, D, ll coupling transformers are significantly better than Y,0 coupling transformer. This has necessarily important for the study of energy loss reduction.


Electronics ◽  
2019 ◽  
Vol 8 (12) ◽  
pp. 1542
Author(s):  
Hyun-Jun Lee ◽  
Dae-Shik Lee ◽  
Young-Doo Yoon

This paper proposes a new unified power flow controller (UPFC) topology. A single phase of them system with the proposed topology consists of an N:2 transformer with a center tap at the low-voltage side and a power converter module comprising full- and half-bridge converters. A three-phase system can be implemented with three devices. While the conventional UPFC topology uses two three-phase transformers, which are called series and parallel transformers, the proposed topology utilizes three single-phase transformers to implement a three-phase UPFC system. By using an autotransformer structure, the power rating of the transformers and the voltage rating of switches in the power converter module can be significantly decreased. As a result, it is possible to reduce the installation spaces and costs compared with the conventional UPFC topology. In addition, by adopting a full- and half-bridge converter structure, the proposed topology can be easily implemented with conventional power devices and control techniques. The techniques used to control the proposed topology are described in this paper. The results obtained from simulations and experiments verify the effectiveness of the proposed UPFC topology.


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