Phase control of an induction motor

A motor comprising:

• a rotor;
• a stator;
• a voltage sensing device configured to measure an alternating current voltage signal applied to the motor;
• a switching element coupled between a power source and the motor;
• and
• one or more control devices configured to selectively control an operating speed of the motor by:
• receiving data indicative of the alternating current voltage signal;
• generating a zero cross voltage signal based at least in part on the data indicative of the alternating current voltage signal;
• determining a phase delay period for a half cycle period of the zero cross signal, the phase delay period based, at least in part, on a desired operating speed of the motor, the phase delay period corresponding to a period of time occurring after a start of the half cycle period;
• and
• controlling operation of the motor by providing one or more control signals to the switching element to cause the switching element to conduct current for a gating period corresponding to a period of time occurring between an end of the phase delay period and an end of the half cycle period.

A control system comprising:

• one or more memory devices;
• and
• one or more processors, the processors storing computer-readable instructions that when executed by the one or more processors cause the one or more processors to perform operations, the operations comprising:
• receiving data indicative of an alternating current voltage signal associated with an induction motor, the alternating current voltage signal being applied to the induction motor through a switching element coupled in series between a power source and the induction motor;
• determining a phase delay period for a half cycle period of a zero cross voltage signal determined based, at least in part, on the data indicative of the alternating current voltage signal, the phase delay period based at least in part on a desired operating speed of the induction motor, the phase delay period corresponding to a period of time occurring after a start of the half cycle period;
• and
• controlling operation of the induction motor by providing one or more control signals to the switching element causing the switching element to conduct current for a gating period corresponding to a period of time occurring between an end of the phase delay period and an end of the half cycle period.