A motor inverter controls a motor's speed and torque by manipulating the power supplied to it. Here's a breakdown of the process:
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AC to DC Conversion: The inverter initially transforms incoming Alternating Current (AC) power into Direct Current (DC) power.
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DC to AC Conversion with PWM: Next, it recreates AC power from the DC power it just created. This conversion utilizes Pulse Width Modulation (PWM). PWM is a technique to control the width of a pulse, effectively controlling the average voltage applied.
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PWM Output: The inverter generates a pulsed voltage output based on the PWM control.
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Smoothing the Output: The motor coil then smoothes out these voltage pulses.
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Sine Wave Current: This smoothing action results in a sine wave current flowing through the motor.
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Motor Control: By controlling the frequency and amplitude of this synthesized sine wave, the inverter precisely controls the motor's speed and torque.
| Step | Description |
|---|---|
| 1. AC to DC | Converts incoming AC power to DC power. |
| 2. DC to AC with PWM | Recreates AC power from DC using Pulse Width Modulation (PWM). |
| 3. PWM Output | Generates pulsed voltage based on PWM. |
| 4. Smoothing | Motor coil smooths out the pulsed voltage. |
| 5. Sine Wave Current | A sine wave current is generated. |
| 6. Motor Control | Controls motor speed and torque by adjusting the sine wave's frequency. |
In essence, the inverter acts as a power intermediary, taking readily available AC power, converting it to DC, and then synthesizing a controlled AC signal using PWM to precisely manage the motor's operation.
