IOT-Based Pressure Transmitter for Condition Monitoring in Smart Grid with Compensation Capabilities

Nowadays, in smart grid infrastructure, incorporating advanced maintenance solutions is a mandatory requirement for effective asset management and enhancing overall system reliability. To achieve this goal, continuous signal monitoring should be considered. Accurate signal measurement and flow in the smart power grid is of great importance. “Strain gauge” sensors are used for more accurate measurement of force, pressure, and weight in industrial scale. These sensors have output with weak voltage and power, which requires signal amplification. In this paper, an IOT -compatible transmitter with network connectivity is proposed. In order to amplify the signal and convert it into digital data, an ADC (Analog to Digital Converter) with 24-bit accuracy is utilized. The data are fed into a microcontroller for further processing. This data have an error due to the temperature non-linearity of the pressure sensor and the ADC chip. Therefore, a calibrated temperature sensor is considered to minimize the non-linear dependence. In order to connect the microcontroller with the industrial IOT network, the Modbus RTU protocol has been selected, which is implemented in the standard RS485 platform. The simulation and test results show that the transmitter is compatible with the industrial digital controllers with the Modbus communication protocol and is resistant to instantaneous overvoltage on the communication line up to 15 kV. In this transmitter, the ability to calibrate and change parameters and coefficients can be done remotely under the Modbus protocol.