Variable speed controller with improved efficiency of energy transfer for an ac induction motor

Patent · Tue Dec 28 04:00:00 EST 1982

OSTI ID:6439161

Jackson, R D

A variable speed controller for an alternating current induction motor reestablishes the start time for firing pulses and clock pulses in a circuit having a uniform frequency generator generating firing and clock pulses. Feedback from the stator terminals sets an oscillator with a sawtooth type ramp output. Subsequent feedback from the stator terminals are compared with the output of the oscillator in a comparator that establishes a time or phase shift in the generated output having the same frequency, for resetting the firing pulses so that the frequency of current to the stator winding is a function of the relationship between the stator and rotor positions, and of the current amplitude in the stator windings. Adjustment of the circuit parameters reduces the difference between the rotor and stator positions and optimizes stator current to maintain flux balance.

• Assignee: Hps Inc
• Patent Number(s): US 4366429
• OSTI ID: 6439161
• Country of Publication: United States
• Language: English

Related Subjects

200301* -- Power Transmission & Distribution-- AC Systems
EHV & UHV-- (-1989)
24 POWER TRANSMISSION AND DISTRIBUTION
AC SYSTEMS
COMPARATOR CIRCUITS
CONTROL EQUIPMENT
EFFICIENCY
ELECTRONIC CIRCUITS
ELECTRONIC EQUIPMENT
ENERGY SYSTEMS
ENERGY TRANSFER
EQUIPMENT
FEEDBACK
INDUCTION
MOTORS
OSCILLATORS
POWER SYSTEMS
PULSES
SPEED REGULATORS
TIMING PROPERTIES