Borgwarner Inc.

Borg-warner Automotive Electronic & Mechanical Systems Corporation

Square D Company

Borg-warner Automotive Gmbh

George H Studtmann

Todd L King

Alan L Miller

William P Umlauf

Donald H Ward

Jerome J Zawada

Kenneth R Gallaher

Stanley B Quinn, Jr

Julius Michael Liptak

James V Fixemer

Harry J Venema

Terry L Forbes

David James Gritter

John K Overzet

Raymond J Yarema

James R Ward

Hsiao J Ma

A solid state circuit interruption arrangement monitors a current path to provide protection to both a load and a solid state switch. The arrangement includes an energy absorber for absorbing energy from the current path in response to the solid state switch interrupting the current path, and a control circuit for periodically generating the interrupt signal to interrupt the current path for prescribed intervals and to control the current supplied to the load between a maximum current level and a minimum current level.

Solid state current controlled interruption system

A solid state circuit interruption arrangement in a distributed power network provides fast and reliable circuit interruption. A common power source provides power to a plurality of loads via respective current paths. A main circuit breaker and a plurality of solid state circuit breakers are arranged to interrupt the current paths in response to command signals sent from a central controller. Current sensors and voltage sensors are coupled to the current paths for monitoring purposes. An automatic controller responds to any of the current sensors detecting a fault condition by automatically generating a command signal, which forces the associated solid state breaker to interrupt the associated current path. Thereafter, the controller automatically generates a signal to the main circuit breaker to interrupt the power provided from the common power source in the event that the associated current path is not interrupted by the solid state breaker. Alternatively, or in addition, the main interruption device may interrupt the current path when its own internal sensing mechanism detects a magnitude of current that is beyond a predetermined level. Also, the controller automatically generates a signal to the main breaker to interrupt the power provided from the common power source in the event that any of the branch breakers fails in the 'off' or interrupted, condition. Other features include a finned housing structure which provides cooling means for the breaker system without the need for cooling fans.

Fail-resistant solid state interruption system

An improved electrically actuated solenoid is used to regulate the function of a hydraulic flow control valve. The solenoid directs a control valve to generate a predetermined output pressure as a function of the solenoid input current. The working air gap surface area is increased by locating it at a greater circumferential radius than the pole piece to increase the air gap permeance, thereby increasing the output force obtainable from a solenoid of relatively small physical dimensions and low cost.

Variable force solenoid hydraulic control valve

A solenoid operated hydraulic control valve system including a solenoid operated valve having a specially ported spool valve to statically balance spool forces in the opened and closed positions.

Solenoid operated hydraulic control valve

A solenoid operated hydraulic control valve which has a specially ported spool valve to statically balance spool force in the opened and closed positions, and a specially designed solenoid operator which includes very small ratios of gaps to cross-sectional areas for the working and non-working gaps between the armature and stator.

A method and apparatus for solenoid driver control of high speed solenoid actuators which includes supplying a high regulated level of acceleration current to operate the actuator, monitoring and controlling the current requirements of solenoid actuation, automatically reducing the solenoid current at a rapid rate to a lesser level of regulated solenoid hold current for the remaining duration of actuator operation, and rapidly reducing the solenoid current between acceleration and holding levels and for rapid solenoid release. Current is controlled at the different levels using switch mode power control techniques for power efficiency.

Driver for high speed solenoid actuator

Stabilized operation of a damperless synchronous motor, which is driven by a voltage source inverter energized by a d-c bus voltage, is obtained under transient conditions, such as during sudden variations of load torque, in order to maintain the torque angle in the motor relatively stable at all times and within the stability limit. This is achieved by employing transient changes in either the d-c bus voltage, the d-c bus current or the motor voltage, which changes reflect transient variations of the torque angle, to rapidly adjust the inverter frequency as necessary to hold the torque angle reasonably constant. For example, if there is an abrupt load increase on the motor, the bus voltage tends to drop and the motor tends to slow down, the torque angle thereby tending to increase. The extent to which the angle tends to increase will, however, be rapidly reduced by dynamically decreasing the inverter frequency so that the rotating magnetic flux or mmf, produced by the stator windings of the motor, slows down to preserve the desired torque angle. When there is a normal variation in load demand, necessitating a different steady state motor speed, a set point voltage may be varied to change the amplitude and frequency of the inverter output voltage to the steady state levels needed to drive the motor at the new required speed.

Control and stabilizing system for damperless synchronous motor

A relatively simple inverter-motor system, comprising a minimum number of circuit components, is provided by employing a voltage-controlled thyristor inverter which in turn drives a synchronous motor having a leading power factor. With the motor current leading the motor voltage, the thyristor switching devices will be motor-commutated, thereby precluding the need for any auxiliary commutating elements or circuits to effect forced commutation. Since, with a leading power factor, the current through a conducting thyristor falls to zero before the thyristor has to be switched off, ample turn-off time is provided. Furthermore, as compared to a conventional forced commutated voltage source inverter, the customary reactive diodes, usually shunting the switching devices in an inverter to permit the flow of reactive motor current, are not necessary. Moreover, by powering the inverter with a voltage source, rather than with a current source, the commutation process is greatly facilitated, the need for damper windings on the motor is eliminated, and the physical size of the d-c link inductor normally required by a current source inverter is greatly reduced.

Voltage-controlled, inverter-motor system

If the thyristor switching devices of a chopper controlled inverter are normally motor-commutated during running operation, a starting system is needed to initially rotate the motor fast enough to develop a sufficient back EMF in the motor for motor commutation to occur. This is achieved by regulating the operation of the chopper to produce bus current pulses and by gating the thyristors on in predetermined sets and in a prescribed sequence to current pulse energize the motor to effect step-by-step rotation. After a set of conducting thryistors have supplied a bus current pulse to the motor, the reactive energy that builds up and becomes locked or stored in the inductances, through which the motor current flows, must be dissipated in order to commutate the conducting thyristors off and reduce the motor current to zero before the next set of thyristors are turned on. The required energy dissipation is accomplished by a circuit path which is effective during the intervals between the bus current pulses from the chopper. A d-c voltage source, in the circuit path causes the reactive energy to be rapidly absorbed, to permit faster turn on of the next set of thyristors and consequently faster starting. Once the motor has reached a speed sufficiently high to permit motor commutation to occur, and SCR is gated on to by-pass the d-c voltage source and provide a low loss free-wheeling path for reactive energy during running operation of the system.

Starting system for chopper controlled motor-commutated thyristor

A pulse-width modulated inverter system and a method for operating the same is described for providing three-phase power to a load at a preselectable output frequency and a preselectable output voltage wherein modulated inverter logic control circuitry is provided for activating switching devices to produce waveforms at output terminals having at least one pulse of a variable width disposed symmetrically about the center or 90.degree. point in the middle 60.degree. portion in each half cycle thereof. The width of the pulses are varied continuously to obtain the preselected output voltage. The number of pulses to be added in the middle 60.degree. portion in each half cycle of the waveforms is increased automatically and continuously as the preselectable output frequency is reduced.

Pulse-width modulated inverter system and method

An a-c supply system includes an input bridge circuit, connected to receive a-c input voltage and produce an output d-c voltage which is passed through a filter to an inverter having a plurality of thyristor switches, which switches are regulated to produce an a-c output voltage for supplying a load. If two of the switches are inadvertently triggered on to produce a fault across the bus, the rapid discharge of the filter capacitor into this fault is sensed, and the protection circuit provides both simultaneous turn-on of all of the inverter power switches, and turn-off of the input bridge. The input bridge turn-off is achieved by simultaneous removal of the gate drive from all the power switches in the input bridge and commutation of all the power switches in the input bridge circuit, or by interrupting power transfer from the input bridge toward the inverter. In addition to sensing the filter capacitor current, the level of current supplied to the input bridge is monitored so that a sudden rise is detected and utilized to initiate the same protective functions.

Fault protection circuit

A system for indicating torque and/or speed of a rotatable shaft includes a transducer positioned adjacent the shaft. The transducer has two primary windings wound in a bifilar arrangement on the same magnetic core structure. The primary windings are connected in a manner to facilitate driving of the transducer primary windings with a simple switching circuit.

Torque transducer with closely coupled primary windings

A bipolar inverter has power switches connected such that the inverter can be energized with a d-c voltage of either polarity, or by an a-c voltage. Each power switch of the bipolar arrangement can include inverse-parallel connected thyristors, an individual triac, or a diode bridge with a thyristor connected across the bridge. A commutation circuit for a bipolar inverter is described. A single power switch also has utility as a power transfer component in addition to its use with an additional power switch in one leg of a bipolar inverter. Different circuit implementations for the bipolar inverter are described, including use with an induction generator, a heterodyne frequency converter, and a power regeneration system.

Bipolar inverter with induction generator

A background discussion of induction machine equivalent circuits, including operation as an induction generator, is provided. Selective shorting of the machine terminals is described, to convert at least some of the mechanical input energy into electrical field energy for the machine. Systems are described for accomplishing the selective shorting with a single-phase machine, including sensing of the zero-crossing of the output voltage to insure that the shorting is effected at the appropriate time to replenish the field. The shorting time duration can be varied as a function of load. A three-phase shorting circuit is also described.

Induction generator excitation system

The disclosed voltage generating system includes certain known components, such as an induction machine driven as a generator, the output connections of which are coupled to the normal load connections of a switching system, which can be a bridge-type inverter. The system switching frequency f.sub.1 is regulated by firing pulses from a logic circuit in turn controlled by an oscillator. By controlling operation of the inverter switches with respect to the synchronous frequency (mechanical rotational speed) of the machine, a d-c voltage is provided on the normal inverter bus conductors. In the disclosed system the conventional inverter switches (such as SCR's) are replaced by true two-way power switches, capable of passing current in either direction. In addition the firing signals provided by the usual logic circuit and applied to these power switches are modified so that the switching occurs as a function not only of the first oscillator frequency f.sub.1 but also of signals received from a second oscillator at a frequency f.sub.2. In brief, the switching is accomplished with a gate circuit including an exclusive OR arrangement, fed by both the first and second oscillators, to produce an a-c output voltage on the inverter bus conductors. The frequency of this a-c output voltage is controllable independently of the generator speed, and the output voltage amplitude is controllable independently both of generator speed and load variations. By using an induction machine with multiple windings, and plural switching systems, multi-phase voltages can be supplied over multiple conductors to energize an a-c load.

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Mount Prospect, IL, United States of America

George H Studtmann