A/D conversion manner null of electric power system digital conservation control

摘要

PURPOSE: To enhance the conversion accuracy of A/D-converted digital data by applying plural number of times of A/D conversion to an analog input signal so as to obtain a mean value while a sample-and-hold circuit holds the signal and using the mean value for an A/D-conversion value. ;CONSTITUTION: Analog input signals V1, V2, Vn are given to analog filters 1, 2, 3, in which an undesired high frequency component for the A/D conversion is eliminated. Then the output of the analog filters is given to sample-and-hold circuits 4, 5, 6. The sample-and-hold circuits sample/hold the received signal in a timing of a sample-and-hold command signal 1a. Output signals from the circuits 4, 5, 6 are given to a multiplexer 7, which multiplexes the received signal based on a switching signal 1b and the result is given to an A/D converter 8. That is, while the analog signal is in holding, the signal is A/D- converted for plural number of times and the mean value is obtained and the mean value is used for the ADD-converted value to enhance the A/D conversion Precision.;COPYRIGHT: (C)1995,JPO