Patent ID: 7275021
Filing Date: 2007-09-25
Classification: H02M

Abstract:
1. A method for measuring a quantity of a power converter apparatus consisting of parallel-connected power converter units wherein a component quantity of each power converter unit is measured, the component quantities are transmitted digitally in serial communication format to a control unit, and the component quantities are summed to produce a summed quantity, in the method comprising: transmitting the component quantity data to the control unit with the least significant bit (LSB) first, starting the summing as soon as the LSBs of the component quantities have been received, transmitting the LSB of the sum further as soon as the LSBs of the component quantities have been summed, summing the rest of the bits in the order of arrival, with the most significant bit last, and transmitting the respective summing data further in the order of arrival as soon as the corresponding bits of the component quantities have been summed, wherein the converter units transmit their respective data to be summed in such manner that the data are scaled to make them equal in sign, by adding 50% of the measuring range to them, the data thus being always positive.