Inverter AC are equipped with a rectifier that converts the incoming alternating current into a direct current. The direct current is routed to a modulator that converts the direct current back into alternating current of the required frequency. The converted alternating current is supplied to a variable frequency drive that supplies power to the electro-motor that runs the compressor. The frequency of the converted alternating current and the frequency of the drive are directly proportional to each other. When the frequency supplied is high, the drive supplies higher power to the motor of the compressor resulting in increased speed of operation. Conversely, when the frequency supplied is low, the compressor works at reduced speed. An inverter AC accelerates the working of the compressor to cool a room to the required temperature as quickly as possible and then maintains the temperature at that level in an energy-efficient way by reducing the speed of the compressor motor.
At Start Up
When the AC is switched on, the converted alternating current from the inverter connects with a modulator that generates the maximum amount of power to the compressor thus enabling the rapid cooling of the room to the level desired and set on the thermostat. The AC is provided with a micro-processor sensor that assesses the temperature of the room from the flow of air from the room into the AC. This information is relayed to the variable speed drive that then controls the speed of revolution of the electro motor of the compressor.
Once the ambient temperature in the room synchronizes with the temperature set, the modulator regulates the frequency of the current and maintains the temperature at the level achieved with minimum usage of power.
The compressor of an inverter AC will always be in operation but at varying speeds. The variable frequency drive controls the frequency of current supplied to the compressor depending upon the need for cooling. Unlike conventional AC, there is no cycle of start – stop – restart. Consequently, the operation is virtually silent and the continuous smooth operation removes the stress on the electro-motor caused by the sudden torque in case of fixed speed air-conditioners thereby increasing life-span. The elimination of the torque at the start of each compressor cycle combined with supply of voltage on as-demanded-for-cooling basis controls power consumption, and also lessens the pressure on the infrastructure caused by sudden demands for substantially increased power.