ANALOGUE SYNCHRONOUS AMPLIFIER Russian patent published in 2022 - IPC G01R19/10 H03F3/191 

FIELD: electrical measuring equipment, voltage measuring devices.

SUBSTANCE: invention can be used to compare two alternating voltages and measure their difference in metrological installations, for example, in an inductive divider. The analog lock-in amplifier contains a differential amplifier whose inverting input is connected to a reference voltage source and the non-inverting input is connected to a source of a comparable voltage. Output of differential amplifier is connected to the voltage amplifier. A phase shifter is connected to the first input of the first synchronous detector. The output of the first synchronous detector is connected to the first low pass filter. The buffer operational amplifier input is connected to reference voltage source. The output of the buffer operational amplifier through a common point is connected to the negative output of the first solar PV module and the positive output of the second solar PV module. The positive output of the first solar PV module is connected to positive power input of the differential amplifier, negative power input of which is connected to the negative output of the second solar PV module. The output of the buffer operational amplifier through a common point is connected to the negative output of the first solar PV module and to the positive output of the second solar PV module. The positive output of the first solar PV module through a common point is connected to the voltage amplifier positive input and to the positive input of the first analog-to-digital converter. The negative output of the second solar PV module through a common point is connected to the voltage amplifier negative input and to negative input of the first analog-to-digital converter. Voltage amplifier output is connected to the input of the first analog-to-digital converter that is connected to the block of galvanic isolation connected through a common point to the second input of the first synchronous detector and the first input of the second synchronous detector. The first low pass filter is connected to the first digital input of the microcontroller. The output of the reference voltage generator is connected to the input of the second analog-to-digital converter the output of which is connected to the input of the phase shifter; its the second output is connected to the second output of the second synchronous detector, the output of which is connected through the second low pass filter to the second digital input of the microcontroller connected to the screen.

EFFECT: expanding the arsenal of measuring instruments, as well as increasing the information content of the measurements.

1 cl, 1 dwg