Requirements for smart grid are higher efficiency using power electronics and ensuring reliability of components. Refrigeration system is readily used in industries and is now becoming a commonly used household application. Now a day, voltage source inverter based BLDC drive is emerging as a more efficient controller option for refrigeration systems compared to conventional induction motors. Importance of smart grid in today's power scenario has lead to the increasing number of power electronic components for energy efficient operation. It is to be noted that, the reliability analysis of power electronic devices is very important owing to the absence of redundancy in these systems. Due to variable load on BLDC drive in refrigeration system, the component stresses and temperature cycles are necessary to be incorporated for predicting the lifetime and effective design methodologies. The major contribution of this paper is to present the method for reliability analysis of BLDC drive driven by IGBT based inverter and the overall refrigeration system. This particular method can be extended to any drive system in absence of the reliability data from the handbooks or manufacturer catalogs.