“…Depending upon the types and the sizes, Table 2 depicts the existing categories of DGs (Singh et al, 2008; IEEE Task Force on Load Representation for Dynamic Performance, 1993;Quial et al, 2011;Hossein and Morteza, 2012;Kumar and Mittapalli, 2014;Payasi et al, 2012a,b;Chiradeja and Ramakumar, 2014;Holland, 1975a,b;Khajehzadeh et al, 2011;Singh et al, 2015;Sanchez et al, 2015;Kousksou et al, 2015;Mallol et al, 2015). The four broad categories of DGs named as T 1 , T 2, T 3 and T 4 are discussed in details in Singh et al (2008Singh et al ( , 2015, IEEE Task Force on Load Representation for Dynamic Performance (1993), Quial et al (2011), Hossein andMorteza (2012), Kumar and Mittapalli (2014), Payasi et al (2012a,b), Chiradeja and Ramakumar (2014), Holland (1975a,b), Khajehzadeh et al (2011), Sanchez et al (2015, Kousksou et al (2015) and Mallol et al (2015). Valipour (2012aValipour ( ,b, 2013Valipour ( , 2015a and Khoshravesh et al (2015) are also very much useful literatures on the importance of optimization and optimized values (in other fields) to enhance the literature and to indicate advantages of this research work.…”