Iot-based automated voltage controller system for motor operated three-phase autotransformer

An IoT-based automated voltage controller system for motor-operated three-phase autotransformer, the controller system comprising:

• a single-phase bidirectional synchronous motor mechanically connected with a shaft of the autotransformer, the motor comprising a series combination of a wire-wound resistor and a capacitor connected in parallel to the windings thereof that change tapping of windings of the autotransformer through dials;
• two voltage sensors (V1, V2) connected to output of the autotransformer;
• a hall effect current sensor;
• a switch mode power supply (SMPS) circuit to supply power to the voltage controller unit, which primarily steps down the voltage to 5V and rectify thereto into DC voltage;
• a LCD display for displaying live data such that the current through the autotransformer is not beyond the specified rating;
• an alpha-numeric keypad to input target output voltage;
• an Arduino-nano microcontroller associated with a plurality of modules comprising:
• an input voltage module, to receive initial voltage supplied to the autotransformer to activate thereto to be operational, the initial voltage being the primary input to the autotransformer;
• an initial dial positioning module, which sets the dial of the autotransformer at zero output voltage, corresponding to tapping at a primary winding's full turns;
• a feedback voltage module, which receives voltage from one of the two voltage sensors to provide feedback to the microcontroller about the actual output voltage generated by the autotransformer;
• a reference voltage module, which receives a reference voltage as input by an operator using the alpha-numeric keypad connected to the microcontroller;
• voltage analysis module which compares the reference voltage with the feedback voltage obtained from the voltage sensor immediately as the reference voltage is received;
• forward relay activation module, which activates the forward relay if the reference voltage is greater than the feedback voltage;
• backward relay activation module, which activates the backward relay if the reference voltage is lesser than the feedback voltage;
• voltage monitoring and adjustment module, which continuously monitors the feedback voltage and adjusts operation of the autotransformer to maintain a minimum difference of 4 Volts between the reference and feedback voltages during operation;
• and
• display module, which displays target output voltage as achieved and other information comprising input voltage, output voltage, turns ratio (V1/V2), and line current (if any load is connected);
• wherein the output voltage of the motor-operated three-phase autotransformer remains either constant or varies at +4V irrespective of nature of power supply automatically during full load conditions, thereby compensating supply voltage fluctuations.