Patent ID: 8701633

Claim:
A method of operating an internal combustion engine comprising the steps of: supplying fluid to charge air using an injector which in each operation delivers a set amount of fluid; controlling how much fluid is supplied to the charge air in each engine, cycle by controlling how many times the injector operates in each engine cycle; determining from engine speed and load a desired fluid demand as a number of operations of the injector calculated to at least one decimal place; always rounding the desired fluid demand down to a near integer to provide an output fluid demand for the injector as a number of operations of the injector for the next operating cycle; calculating in each engine cycle a difference between the desired fluid demand and the output fluid demand; aggregating the difference over a plurality of engine cycles; and when the aggregated difference is equal to or greater than a predetermined value, then for the next engine cycle increasing the output fluid demand for the injector by the predetermined value, and decreasing the aggregated difference by the predetermined value.