**7. References**

Acha E, Fuerte-Esquivel C, Ambiz-Perez (2004) FACTS Modelling and Simulation in Power Networks. John Wiley & Sons.

Adamczyk, A.; Teodorescu, R.; Mukerjee, R.N.; Rodriguez, P., Overview of FACTS devices for wind power plants directly connected to the transmission network, *IEEE International Symposium on Industrial Electronics (ISIE)*, Page(s): 3742– 3748, 2010.

**Pij with wind/Facts**

**Pij Max**

**0 5 10 15 20 25 30 35 40 45**

**Branche (i-j)**

Fig. 17. Active power transit (Pij) with hybrid model: Case 2: Abnormal Condition: without

A three phase strategy based differential evolution (DE) method is proposed to enhance the power quality with consideration of multi hybrid model based shunt FACTS devices (STATCOM), and wind source. The performance of the proposed approach has been tested with the modified IEEE 30-Bus with smooth cost function, at normal condition and at critical loading conditions with consideration of contingency. The results of the proposed hybrid model integrated within the power flow algorithm compared with the base case with only conventional units (thermal generators units). It is observed that the proposed dynamic hybrid model is capable to improving the indices of power quality in term of reduction

Due to these efficient properties, in the future work, author will still to apply this algorithm to solve the practical optimal power flow of large power system with consideration of multi hybrid model under severe loading conditions and with consideration of practical

Acha E, Fuerte-Esquivel C, Ambiz-Perez (2004) FACTS Modelling and Simulation in Power

Adamczyk, A.; Teodorescu, R.; Mukerjee, R.N.; Rodriguez, P., Overview of FACTS devices

for wind power plants directly connected to the transmission network, *IEEE International Symposium on Industrial Electronics (ISIE)*, Page(s): 3742– 3748, 2010.

**0**

voltage deviation, and power losses.

Networks. John Wiley & Sons.

line 1-2: IEEE 30-Bus

**6. Conclusion** 

constraints.

**7. References** 

**20**

**40**

**60**

**Power Transit (MW)**

**80**

**100**

**120**

**140**


**3** 

*Thailand* 

**Modeling of Photovoltaic Grid Connected** 

**Identification for Power Quality Analysis** 

Khanchai Tunlasakun1, Juttrit Thongpron1,2, Dheerayut Chenvidhya1, Anawach Sangswang1, Veerapol Monyakul1 and Ballang Muenpinij1

Photovoltaic systems are attractive renewable energy sources for Thailand because of high daily solar irradiation, about 18 MJ/m2/day. Furthermore, renewable energy is boosted by the government incentive on adders on electricity from renewable energy like solar PV, wind and biomass, introduced in the second half of 2000s. For PV systems, domestic rooftop PV units, commercial rooftop PV units and ground-based PV plants are appealing. Applications of electricity supply from PV plants that have been filed total more than 1000 MW. With the adder incentive, more households will be attracted to produce electricity with a small generating capacity of less than 10 kW, termed a very small power producer (VSPP). A possibility of expanding domestic roof-top grid-connected units draw our attention to study single phase PV-grid connected systems. Increased PV penetration can have significant [1-2] and detrimental impacts on the power quality (PQ) of the distribution networks [3-5]. Fluctuation of weather condition, variations of loads and grids, connecting PV-based inverters to the power system, requires power quality control to meet standards of electrical utilities. PV can reduce or improve power quality levels [6-9]. Different aspects should be taken into account. In particular, large current variations during PV connection or disconnection can lead to significant voltage transients [10]. Cyclic variations of PV power output can cause voltage fluctuations [11]. Changes of PV active and reactive power and the presence of large numbers of single phase domestic generators can lead to long-duration voltage variations and unbalances [12]. The increasing values of fault currents modify the voltage sag characteristics. Finally, the waveform distortion levels are influenced in different ways according to types of PV connections to the grid, i.e. direct connection or by power electronic interfaces. PV can improve power quality levels, mainly as a consequence of increase of short circuit power and of advanced controls of PWM converters and custom

Grid-connected inverter technology is one of the key technologies for reliable and safety grid interconnection operation of PV systems [14-15]. An inverter being a power

**1. Introduction** 

devices. [13]

**Inverters Based on Nonlinear System** 

Nopporn Patcharaprakiti1,2, Krissanapong Kirtikara1,2,

*1King Mongkut's University of Technology Thonburi, Bangkok, 2Rajamangala University of Technology Lanna, Chiang Mai* 

