This paper presents theoretical and experimental evaluation of DC-DC converters used with photovoltaic (PV) power systems.  Criteria for converters used with PV systems are discussed and a fairly detailed simulation of a PV system which includes different types of DC-DC converters is built. The simulation is used to assess the performance of the most common DC-DC converters over a wide range of loads, irradiation levels and duty ratios. The presented simulation results are verified experimentally using a DSP-based laboratory system. The results illustrate clearly that the range of change in converter duty ratio to operate at maximum power point is smaller with Cúk converter which leads to more reliable and stable operation of PV system with Cúk converter. This result is, also, of prime importance to power system engineers forming a useful guide to design and operate PV systems at maximum power point without additional complexity, leading to the design reliable and low cost PV system for remote areas ,rural villages and desert development applications.