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Elements such as high-efficiency & optimization have seen switching power converters gradually replace the role of linear power converters.High frequency power supplies and high voltage are used considerably in high voltage applications,namely industry applications,X-ray high voltage applications,electrostatic precipitation,atmospheric pressure plasma processing,diagnostics in medicine,etc.The LCC criteria however presents a reliable option incorporated in its topology,making upmost use of leakage inductance & convoluting capacitance to remove the negative effects of converter operation.The LCC Series-Parallel Resonant Converter adopts the desirable properties of both the Parallel and Series Resonant Converter which include reduced peak currents,miniature variations in switching frequency and high efficiency.This renders it a viable choice in most power and energy applications.Although there are several models and control schemes in literature,in this paper a Sliding Mode Control approach for the enunciated LCC-type converter is employed.Sliding Mode Control(SMC)is a satisfactory robust control technique suitable for a specific array of nonlinear systems.The sliding surface or hyperplane,which allows a control signal to direct trajectory points,in this paper is based on current-mode control.The configuration of the SMC controller is robust-amplitude modulated.Sliding Mode Control(SMC)though effective boasts of certain control constraints,PI(Proportional-Integral)control to sliding function is utilized against Zero Output Voltage Steady-State Error.Integration of protection circuit and hysteresis band remove current limitation and constant switching frequency.The small-signal modelling analysis was done to equalize and mathematically derive the system parameters and criterion due to its non-linearities.Its aided in the clear and concise representation of the system including its relevant state-space approximations.The main process of the SMC algorithm is to capture power stage parameters and simulate them towards the desired system operation point(SMC sliding surface)via Averaging,Steady State,Linearization and Iteration.Sliding mode approach is able to disregard certain anomalies and irregularities in converter topology thereby achieving good results.