Abstract: A method is provided for determining a value for an electrical output of a converter of renewable energy. The method comprises obtaining a signal representing the electrical output of the converter wherein that electrical output has an initial value. The method further comprises applying a pulse signal to the signal representing the electrical output, wherein the pulse signal comprises a positive portion and a negative portion. The method further comprises obtaining a measurement of electrical power produced by the converter during application of the pulse signal, removing the pulse signal and then obtaining a measurement of electrical power produced by the converter in the absence of the pulse signal. An error value is determined from the obtained electrical power measurements and that error value is applied to the initial value to obtain a target value for the electrical output of the converter.

Abstract: A method is provided for determining a value for an electrical output of a converter of renewable energy. The method comprises obtaining a signal representing the electrical output of the converter wherein that electrical output has an initial value. The method further comprises applying a pulse signal to the signal representing the electrical output, wherein the pulse signal comprises a positive portion and a negative portion. The method further comprises obtaining a measurement of electrical power produced by the converter during application of the pulse signal, removing the pulse signal and then obtaining a measurement of electrical power produced by the converter in the absence of the pulse signal. An error value is determined from the obtained electrical power measurements and that error value is applied to the initial value to obtain a target value for the electrical output of the converter.

Abstract: An electrical power generating system based on a photovoltaic cell array comprises means for monitoring the output of the array in order to determine whether the output is sufficient to sustain supply to a connected power network. The output of the array is monitored by sensing the voltage across a resistor connected across the array output. The array is connected to the network when a predetermined threshold is reached.