Till now I have all the Pressure regulating hardware and software ready. All the tests are performed successfully. GUIs are used to monitor as well to control the motors.
The Hardware also is tested with the actual VFDs and motors. Till now, the steam pressure to the accumulator was simulated using another GUI. So now I have started to work on pressure sender hardware.
The main purpose of Pressure sender hardware is to read the pressure of the steam to the accumulator and send this to the VFD controller PCBs in the field over ethernet layer using UDP protocol. The actual distance between steam accumulator and the parabolic dishes is more than 100 meter, so direct connection of pressure sensor to the VFD controllers was not possible.
Apart from sensing pressure, steam temperature also needs to be monitored so the the heat energy in the receivers can be predicted. So a K-type thermocouple is also going to be used.
The pressure sensor is going to be standard with output range of 0V - 10V DC. This value is then stepped down to 0 - 5V DC using resistor network so as to make it compatible with arduino voltage levels.
For temperature sensing K-type thermocouple is to be used. AD8495 from Analog devices is used to amplify very small signals of thermocouple to higher range. AD8495 provides the resolution of 5mV/°C.
I am going to use the same hardware of VFD controller with slight modifications. RS485 interface is not required, so that part will be removed and resistor divider for pressure sensor and AD8495 IC for thermocouple will be added.