AC motor control using pulse-width modulation

Asinhronski elektromotorji predstavljajo ključni sestavni del sodobnih industrijskih procesov. Te običajno napaja napetostni vir s konstantno frekvenco, ki jim določa vrtilno hitrost. Frekvenčniki so elektronske komponente, ki nam omogočajo prilagajanje vrtilne hitrosti asinhronskega elektromotorja. Naš cilj je bil izdelava prototipa frekvenčnika po nižji ali primerljivi ceni s komercialnim ekvivalentom. Proučili smo osnovne krmilne sposobnosti mikrokrmilnika Arduino Uno in naprednejše nastavitve mikročipa, na katerem temelji njegova arhitektura. Napisali smo program, ki omogoča generiranje visokofrekvenčnih PWM-signalov. Krmilni signal preko izdelanega logičnega vezja preklaplja napajalno napetost na posebno izdelanem inverterskem sistemu, ki poganja naš trofazni asinhronski elektromotor. Elektromotor smo uspešno krmilili znotraj delovnega območja, vendar cenovna dostopnost projekta ni dosegala zastavljenih ciljev.AC motors are a key component of modern industrial processes. They are usually powered by a constant-frequency power source that controls their rotational speed. Variable-frequency drives are electronic components that adjust the rotational speed of an AC motor. Our goal was to make a variable-frequency drive prototype at a price lower than or equal to that of variable-frequency drives available on the market. We examined the basic control capabilities of the Arduino Uno microcontroller and the more advanced settings of the microchip that provides the basis of its architecture. We have written a program that enables the generation of high-frequency PWM signals. Through the constructed logic circuit, the control signal switches the supply voltage on a specially designed inverter system that drives our three-phase AC motor. We successfully controlled the AC motor within the working range, but failed to meet our goals as far as the variable-frequency drive affordability is concerned