Multilevel inverters are more suitable in PV applications due to their numerous advantages like better harmonic profile, low dv/dt and requirement of low voltage rating switches so on. Even though conventional multilevel inverters have many advantages, these configurations have some serious drawbacks like neutral point balancing problem, unequal capacitor voltages and more switching losses due to redundant switching combinations. Moreover, conventional multilevel inverters (NPC or flying capacitor) are not reliable, because the inverter will not function if any one switch fails. To address these issues, a novel 31-level inverter configuration is presented in this paper and it can be operated even any power electronic switching device or isolated dc voltage source fails. In this configuration, 31-level voltage waveform is produced by using four isolated DC sources which will have different voltage magnitudes. Availability of isolated dc voltage sources in PV systems is more common. This inverter circuit is developed by using only 12 switching devices where as a conventional 31-level inverter requires 60 switching devices. Detailed analysis of proposed inverter configuration is presented during the failure of different switching devices/isolated dc sources. MATLAB/Simulink is used to simulate the proposed inverter configuration and results are presented for different fault conditions.