Abstract: A reactor capable of eliminating a heat source provided within a power cabinet housing a motor drive device. The reactor includes a tubular core, a coil installed inside the core, a terminal which is provided at an axially first end of the core and which is connected to the coil, and an attachment flange which extends radially outside of the core and which is provided between the terminal and a second end of the core.

Abstract: The present invention provides an apparatus for controlling power factor compensation and method thereof, in which a turn-on timing point of a power factor compensation switch is delayed by a prescribed time from a zero crossing timing point to enhance a power factor. The present invention includes periodically detecting a zero crossing time point of an inputted voltage, turning on the power factor compensation switch if a turn-on time point of the power factor compensation switch set to a time point delayed by a prescribed time from the detected zero crossing time of the inputted voltage is reached, and turning off the power factor compensation switch if a prescribed time passes after turning on the power factor compensation switch.

Abstract: Disclosed is a frequency converter system for altering the frequency of a-c power supplied from a distribution network to a load, the system including a pair of mechanically coupled rotating alternating current machines, the alteration of the rate and direction of rotation of the prime mover altering the frequency of the power. A variable impedance network comprising saturable core reactors and connected in the rotor circuit of the prime mover is utilized to effect the change of rate and direction of prime mover rotation.

Abstract: A circuit provides an electrical output signal proportional to but electrically isolated from a current flowing in a power circuit, and more particularly, to the current supplied to the field or armature winding of a DC motor load which receives power from a rectifier circuit coupled to an AC power source. The circuit includes a transformer including at least two windings, a primary and a secondary, wound on a saturable core. The primary winding is coupled to the power circuit, whereas the secondary winding is coupled to an output circuit along with control circuit means which are adapted to keep the core out of saturation in response to a power current flowing in the primary winding which by itself is adapted to drive the core into saturation. Accordingly, the time the core is not in saturation an output current flows in the secondary winding, which is related to the primary current by the turns ratio of the transformer.

Abstract: Low voltage starting of a three-phase submersible pump motor in a shallow well is achieved by employing a high-impedance transformer for supplying the three-phase power to the motor. Upon starting, the normally heavy current drawn by the motor results in a voltage drop through the high-impedance transformer sufficient to substantially lower the voltage across the motor and hence the starting current. In the absence of limiting the starting current, abnormally high starting torques will be produced on the motor shaft resulting in mechanical fatigue and eventually shaft breakage.

Abstract: A turn off circuit for a multiphase motor is provided, comprising a D.C. powered system including a three element choke core having two outer cores with loosely coupled windings and a central core closely coupled to the outer cores to enhance pulse generation.A modified SCR ring counter is provided to supply D.C. power to the load to produce a three phase wave shape with less wave distortion and lower noise.Pulse width modulation is supplied to the negative SCRs of the ring counter through steering SCRs which are turned on by discharge from capacitors in the steering circuit.Pulse width modulation is fed to the ring counter through the outer core elements, while the central core functions to improve pulse width of the discharge capacitors. Free wheeling energy from the motor is fed to the discharge capacitors and increases firing energy.

Abstract: A turn off circuit for a multiphase motor is provided comprising a DC powered system including a three element core having a central core element and an inner and outer core element coupled thereto.A series of capacitors are connected to an outer core element to discharge simultaneously and turn off positively and negatively biased SCRs which sequentially fire and produce a suitable pulse width and frequency to the motor.A control system is provided to produce a variable pulse frequency and pulse width to a power circuit which sequentially fires and admits battery power to the motor.

Abstract: A turn off circuit for a multiphase motor is provided comprising a DC powered system including a three element core having a control core element and an inner and outer core element coupled thereto.A series of capacitors are coupled to the central core winding to produce suitably shaped pulses to turn off positively and negatively biased SCRs which control power switching SCRs.A control system is provided to produce a variable pulse frequency and pulse width to a power circuit which sequentially fires and admits the battery power to the motor.

Abstract: A transformer having a secondary winding that delivers a regulating magnitude to a speed regulator circuit that approaches zero as the speed approaches the speed setting, is provided with two primary windings wound and connected so that they oppose each other in operation. The first is the conventional primary winding in series with the universal motor of which the speed is being controlled (as by a conduction phase angle control of the input voltage) while the second primary winding is in series with a resistance and, in some cases, also with a capacitor, with this series combination being connected in parallel with the armature winding of the motor for the best regulation, or in parallel with the motor as a whole if it is important to avoid additional internal connections to the motor. The capacitor is used to compensate for the inductive reactance of the second primary winding in cases in which that reactance is not negligible. A second capacitor across the secondary filters out commution "hash.