NOVELTY - The method involves comparing power of a fuel cell system with reference power (S30) at an electronic control unit (ECU) and controlling a target pressure (S110) in an anode of a fuel cell stack to be an oscillating target pressure when the power is lesser than the reference power. A measured differential pressure between two predetermined points is compared (S230) with a reference differential pressure at the ECU. A purge valve operation cycle is reduced (S231) when the measured differential pressure is lesser than the reference differential pressure.    USE - Method for controlling pressure oscillation in an anode of a fuel cell stack within a fuel cell system of a vehicle. Uses include but are not limited to motor vehicle e.g. passenger automobile such as sports utility vehicle (SUV), bus, lorry, commercial vehicle, watercraft e.g. boat and ship, and aircraft, hybrid vehicle e.g. petrol-powered vehicle and electric-powered vehicle, electric vehicle, plug-in hybrid electric vehicle and hydrogen-powered vehicle.    ADVANTAGE - The target pressure in the anode is controlled by the ECU to effectively discharge condensed water that is unnecessarily generated in the anode during an initial startup or under a set of low temperature conditions such as winter temperatures, without an operation of the purge valve. The method enables controlling the target pressure in the anode to periodically oscillate or vibrate the anode to effectively control a flow rate of supply hydrogen, a flow rate of recirculated hydrogen, and opening and closing of a purge valve during an entire operation such as low power operation, of the fuel cell system, thus improving overall fuel efficiency of the fuel cell system, and fuel efficiency and durability of the fuel cell stack. The method enables allowing an ejector to cause a pumping action to prevent degradation in suction performance during the low power operations and facilitate mixing of hydrogen gases in a mixing zone by temporarily increasing the flow rate of supply hydrogen, thus improving pumping performance and increasing stoichiometric ratio (SR) of the fuel cell system.    DETAILED DESCRIPTION - The predetermined points are selected from a group of a coolant line, an inlet or an outlet of the anode. An INDEPENDENT CLAIM is also included for a non-transitory computer readable medium storing a program comprising a set of instructions for controlling pressure oscillation in an anode of a fuel cell stack.    DESCRIPTION OF DRAWING(S) - The drawing shows a flowchart illustrating a method for controlling pressure oscillation in an anode of a fuel cell stack.    Operation information determining step (S20)    Step for comparing power of fuel cell system with reference power (S30)    Anode target pressure controlling step (S110)    Step for comparing measured differential pressure with reference differential pressure (S230)    Purge valve operation cycle reducing step (S231)