Relation formulation between daily and hourly load curve based loss of load expectation indices

This paper develops a conversion function and method transforming from daily peak load curve used LOLED [days/year] to hourly load curve used LOLEH [hours/year] firstly. The indices can not only be conversed just arithmetically but also have different characteristics physically because of using their different load curves. The conversion function is formulated as variables of capacity and forced outage rate of generator, hourly load daily load factor and daily peak load yearly load factor, etc. Therefore, the conversion function (γ = φ(·)) can not be formulated in simple but in complex and difficult. In this study, therefore, the function is formulated as linear times of separated two functions. One is exponential formed conversion function of daily load factor. Another is formulated exponential typed conversion function of daily peak load yearly load factor. Furthermore, this paper presents algorithm and flow chart for conversing from LOLED [days/year] to LOLEH[hours/year]. The proposed conversion function is applied to sample system and actual KPS(Korea Power System) in 2015. The exponent coefficients of the conversion functions are assessed using proposed method. Finally, assessment errors using conversion function for case studies of sample system and actual system are evaluated to certify the firstly proposed method.