Comparison of variable speed drives for single-phase induction motors

Drive for a Symmetrical Two-Phase Induction Machine Using Vector Modulation

“…Thus, the average evolution within the period can be controlled. The sum of times T 1 and T 2 is not always equal to unity, therefore it is necessary to spend the rest of the period on a zero vector, in other words, a vector that does not modify the sum defined by equation (1). Since the sum of the times (T 1 and T 2 ) is smaller than the switching period, to maintain the output voltage constant, zero vectors are used during the rest of the period.…”

“…One of the known methods of varying the speed of a single-phase induction motor with a permanent capacitor (PSC motor) is to remove the capacitor from the auxiliary winding and consider it to be a two-phase machine (1) (2) (6) . In this way, the motor would be fed by a twophase inverter.…”

A Simplified Modulation Strategy for Three-leg Voltage Source Inverter Fed Unsymmetrical Two-winding Induction Motor

“…Variable speed control for single-phase induction motor (SPIM) with a single-phase drive has several serious problems especially at low speed such as low efficiency and average torque, great ripple torque and speed pulsation when compared with a two-phase drive [1][2][3][4][5]. The twophase drive system can be classified as inverter topologies in three types: two-leg, three-leg, and four-leg inverters.…”

Acionamento do motor de indução bifásico simétrico empregando modulação vetorial

“…Sabe-se que um dos méto-dos para a variação de velocidade do motor monofásico com capacitor permanente é retirar o capacitor do enrolamento auxiliar e considerá-lo como uma máquina bifásica (Blaabjerg, 2002;Holmes, 1993;Corrêa, 2003) e, desse modo, o motor seria alimentado por um inversor bifásico. O problema é que os enrolamentos do motor não são idênticos; devido à inserção do capacitor, que forma um circuito ressonante com a indutância do motor, o enrolamento auxiliar fica submetido a uma tensão maior e para tentar preservar a relação tensão/espira dos enrolamentos altera-se o enrolamento auxiliar.…”