Implementation of Microcontroller based Variable Frequency Voltage Measurement Sensor for PLC based Standalone Induction Generator Control

A Standalone Induction Generator generates variable frequency output voltage as mechanical power sources input to the machine are most of the times dynamic in nature. If output of this type of machine is controlled with the help of a Programmable Logic Controller (PLC), then a DC signal which should be proportional to the output voltage of machine may be given to PLC for generation of Control Signals. In this paper an implementation of Microcontroller based proportional dc signal generator is elaborated which can be used as an input sensor for Programmable Logic Controllers. This system is actually a digital peak detector circuit which detects peak of variable frequency voltage signal and converts a magnitude of input voltage signal to proportional DC signal within the range of 0 to 5 Volts DC. Most of the commercial PLCs having even analog input facility are not equipped with AC voltage measurement facility. Hence, to overcome this shortcoming the present study is carried out to propose a microcontroller based voltage sensor for PLCs.