Category: Key Components Explanation and Implementation
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Characterization for Electric Motor
Characterization for electric motor needs to be done in order to obtain machine parameters, which will be used for: Using synchronous motor as an example, following are the equations for machine modeling: φd and φq are the flux on d and q axis. Rs is the stator resistance. Notice that comparing the equations that shown…
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PWM Generation
Overview Following shows a commonly used 3-phase 2 level inverter for electric motor drive: To start with, a PWM control signal for phase A can be generated using a sinusoidal waveform as reference: The peak value of the reference sinusoidal signal is set to 1. This is Per Unit (PU) value, with Vdc as base.…
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Current Regulator
Overview A proper designed current regulator is the key to control the electric motor. As explained in FOC Overview section, following is an example of the control system: Current regulator needs to perform following tasks: The items need to be discussed one by one. Decoupling With voltage equations on dq frame: It can be seen…
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Position Phase Lock Loop
Position is one of the key signals for the FOC algorithm. Due to the nature of high switch frequency and also the harsh working environment, this signal is very noise. In order to have a proper filter for the signal without introducing a phase delay, a Phase Lock Loop (PLL) is usually implemented to process…