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Showing papers on "Variable-frequency drive published in 1983"


Patent
10 Feb 1983
TL;DR: A variable frequency drive for a motor-generator/alternator set which is used to supply electrical power to computer or data processing equipment is described in this article, where the induction motor is driven below the synchronous speed of the generator and a variable speed drive increases the velocity supplied to the generator or alternator.
Abstract: A variable frequency drive for a motor-generator/alternator set which is used to supply electrical power to computer or data processing equipment. Power failures in commercially supplied power results in aberrations and erroneous computations in computers and data processing equipment. An induction motor is used to drive a generator/alternator. The induction motor is driven below the synchronous speed of the generator/alternator and a variable speed drive increases the velocity supplied to the generator/alternator, preferably to a point above its synchronous speed. Therefore, when there is a commercial power failure, the generator/alternator remains within a desired frequency range for a longer period of time than a comparable generator/alternator driven at synchronous speed.

21 citations


Patent
04 Feb 1983
TL;DR: In this article, the phase of gate pulses of a 2-phase induction motor was reduced by displacing and generating the phases of a plurality of switching elements of the motor's output, and the gate drive pulses were not synchronized with each other.
Abstract: PURPOSE:To reduce the capacity of a power source by displacing and generating the phase of gate pulses of respective plurality of switching elements. CONSTITUTION:A synchronous pulse (d) synchronized with the voltage of a single phase power source V is inputted from a power source synchronizer 3 to exclusive OR circuits 2a, 2b, and outputs c1, c2 having periods responsive to the set speed of a motor M are inputted from a 2-phase circuit 1 to exclusive OR circuits 2a, 2b. The outputs of the circuits 2a, 2b are inputted to an AND circuits 4a, 4b together with a phase control pulse (f) synchronized with the voltage of the power source V and having a pulse width proportional to the set speed and the output or inverted output from an unstable circuit 9, and the gate circuits G1, G2 of the switching elements of a 2-phase induction motor are controlled by the output. The gate drive pulses g'1, g'2 are alternately generated, and are not synchronized with each other.

1 citations