Abstract: A gas turbine power plant is provided with an industrial gas turbine which drives a rotating brushless exciter generator coupled to a power system through a breaker. One or more of the turbine-generator plants are operated by a hybrid digital computer control system during sequenced startup, synchronizing, load, and shutdown operations. The program system for the computer and external analog circuitry operate in a multiple gas turbine control loop arrangement. Automatic synchronization is achieved with a hybrid subsystem which includes the programmed computer and external phase detection circuitry. An automatic synchronization program for the computer is divided into rough speed and voltage matching, fine speed matching and breaker closure subprograms.

Abstract: A steam turbine is provided with an electrohydraulic control system having an automatic control which includes a digital computer and further having a manual backup control for operating the turbine on automatic or operator switchover to backup control. The automatic control includes control elements and logic elements associated with valve control loops coupled to the turbine and high and low limits and other constants, setpoints and other parameters are characteristic to these control and logic elements and the interrelations among them and the turbine. A switch arrangement is provided for generating parameter value signals corresponding to changed values for the system parameters and for coupling the parameter value signals to the automatic control system where they are registered. The automatic control system is structured to reject invalid parameter value changes and to register only those parameter value changes which can be validly entered as part of the system structure.

Abstract: Electric motors which are used for instance as driving motors for drilling and cutting implements incorporated in the handle of such implements, are subjected to strongly varying loads. This puts heavy demands to the regulation system of the motor. In a regulation system the signals which are provided by detectors (22) for currently sensing the position of the rotor relative to the stator, are supplied to a pulse generator (44, 46) which provides a pulse frequency being uniquely associated with the period of the varying detector signal. This pulse signal is supplied to a frequency-to-voltage converter (48) which provides an output signal being supplied to a diferential amplifier (50) as one input signal thereof, the other input signal being a reference DC voltage, and the output signal of the amplifier being supplied to a multiplier unit (40, 42) as one input signal thereof, the other input signal being said detector signal.

Abstract: A generation control apparatus for vehicle generator normally controls the energization of the vehicle generator in response to a terminal voltage of a battery which is charged by the generator through a rectifier. The generation control apparatus includes a fault detection circuit to detect an abnormal condition of the terminal voltage of the battery or the output voltage of the generator, and if the abnormal condition is detected, a changeover circuit effects the control of the energization in accordance with the output voltage of the generator instead of the battery terminal voltage.

Abstract: A circuit arrangement for windshield wiper motor protection including circuits for pulsing the motor with a variable pulse interval pattern. The pulse interval is generated by circuits which are responsive to motor speed from a comparison with a reference. The motor is automatically deenergized when it is overloaded or stalled.

Abstract: A dynamic stabilizer of the type which is utilized to compensate or stabilize the effect of subsynchronous resonance oscillations in a turbine generator system is taught. Silicon controlled rectifiers are connected in series with inductors between the lines of the electrical system. The silicon controlled rectifiers may be maintained at two quiescent conduction intervals of 90.degree. and 135.degree. depending upon the peak value of rotor oscillation. If the peak value of rotor oscillation is sufficiently small the lower conduction interval of 90.degree. is utilized as this is sufficient to stabilize low level oscillations. Furthermore, it has great advantage in the fact that the losses represented by 90.degree. quiescent conduction interval are relatively small when compared with the larger quiescent conduction interval.

Abstract: A turbine generator or motorized compressor wherein the blades of the turbine or compressor serve as armature conductors for a DC homopolar machine having a single stator which serves as a housing for the turbine or compressor and houses a field coil.

Abstract: A gas turbine power plant is provided with an industrial gas turbine which drives a rotating brushless exciter generator coupled to a power system through a breaker. One or more of the turbine-generator plants are operated by a hybrid digital computer control system during sequenced startup, synchronizing, load, and shutdown operations. The program system for the computer and external analog circuitry operate in a multiple gas turbine control loop arrangement. Logic macro instructions are employed in programming the computer for logic operations of the control system.

Abstract: A voltage converter of the transformer type which incorporates at least one switching transistor coupled to control the application of current to the transformer primary and circuitry for switching the transistor on and off to control the current through the primary winding. When the output of the converter is shorted, the switching rate undesirably increases causing potential damage to the converter. A frequency detecting circuit detects the increase in switching frequency and acts to reduce the input voltage to the converter to prevent damage thereto.

Abstract: A current sensing circuit monitors the currents flowing through the stator windings of a nutating motor. The current drive circuits for the windings are capable of delivering large currents with a fast rise time so that the magnetic circuits of the nutating motor quickly saturate, providing precise operation of the motor. Steering diodes quickly discharge the windings into the power supply. When a predetermined winding current level is exceeded, the current sensing circuit produces an output signal which momentarily disables the current drive circuits for the windings so that the stator winding currents are limited to levels sufficient to precisely operate the nutating rotor. The sensing circuit has a hysteresis characteristic which in conjunction with the energy stored in a winding causes the current in a winding to be maintained between certain maximum and minimum levels.

Abstract: The invention relates to an automatic switching arrangement for two batteries which are charged in parallel and discharged in series. The arrangement includes a control unit and a charging circuit; the control unit is a circuit which includes a transistor (T1), a resistor (R1) and a diode (D1) which is connected between two terminals of opposite polarities of the batteries (BT1) and (BT2), the transistor being blocked or conductive according to the direction of the voltage at the terminals of the diode; the transistor controls switching units (T2,T3) of the charging circuit. A switch (CT4, Th, CT11) can be disposed in series with the diode (D1). Application to stand-by batteries.

Abstract: An electric motor having a construction to insure full utilization of driving currents containing significant harmonic energy. The stator field current may be provided from a multi-phase source or switched electronically through optical sensing of rotor position to eliminate mechanical commutation. Motor torque is made variable by controlling the duration of field current pulses supplied to the stator winding, which also permits variable regenerative dynamic braking of the motor.

Abstract: A system for controlling rotational direction switchover and for variably controlling the rotational speed of a motor comprises a circuit for switching over the rotational direction of the motor, a circuit for supplying rotation driving voltage to the motor thereby to drive it at a speed depending on the rotation driving voltage, a single voltage varying unit for varying voltage continuously, and a control signal generation circuit which receives variable voltage from the voltage varying means to generate a rotational control signal for the rotation driving voltage supplying circuit and further to generate a rotational direction switchover control signal for the switchover circuit. The voltage of the rotation control signal produced by the control signal generation circuit decreasing as the variable voltage approaches a predetermined value, reaching a minimum when the variable voltage coincides with the predetermined voltage, and increasing as the variable voltage goes beyond the predetermined value.

Abstract: In a control signal transmitter for the commutating device of an electronically commutated motor, which contains at least two rotor position transmitters, particularly Hall effect generators, and an evaluation circuit which derives control signals for the commutating device from the output signals of the rotor position transmitters which determine the individual switching instants for the switching elements of the commutating device, in order to permit operation with a higher number of pulses, the evaluation circuit also includes a logic circuit to which the output signals of the rotor position transmitters are fed which circuit furnishes further control signals for the commutating device.

Abstract: The polarity of the desired speed voltage of a speed control device and the commutation sequence of the current flowing in the stator windings are reversed for reversing an electronically commutated D.C. motor. A voltage, proportional to the EMF ad obtained from the motor voltage by I.times.R compensation, is used as the actual speed voltage for the speed control device, the polarity of the voltage proportional to the EMF being reversed when the direction of rotation signal changes.

Abstract: An automatic door closer providing for use as a light duty door opener and having a slip clutch for protecting the electric gear drive power unit from damage due to overspeeding on excess loads applied by overriding manual door operation. Zener diodes across the power supply to the electric drive motor effectively throw a heavy electrical load on the motor and cause the clutch to slip if the motor is sufficiently oversped and caused to act as a higher voltage bucking generator, as by manually forcing the door substantially faster in the direction in which it is being driven. A direct current motor is used at considerably lower than its rated voltage so that electrical power may be safely applied continuously for holding the door closed with the motor stalled, and without the clutch slipping, with the clutch set to slip only when the force applied thereto is significantly higher than the force required to stall the motor yet safe for the drive unit.

Abstract: A battery charging device which is driven by a torsional spring. A gear train driven by the spring is coupled with a wheel having peripheral teeth. A control lever is reciprocated pivotally by a small spring to engage the teeth of the wheel in a manner to control its rotation. The wheel in turn applies impulses which help to keep the lever in motion. The gear train is also coupled with an alternator such that the intermittent movement of the gear train is used to drive the alternator. The electrical current produced by the alternator is used to recharge a battery. An electric motor operates in combination with the switch mechanism to automatically wind up the torsional spring when it has been unwound below a preselected tension level.

Abstract: A hybrid digital computer gas turbine power plant control system which may operate in a multiple control loop arrangement is provided with selected process variable monitoring and control and turbine system failure detection means. More specifically, open, shorted, grounded and reversed thermocouples are detected and alarmed. Problems of any one combustor in a multiple combustor arrangement are similarly detected and alarmed. Additionally, automatic correction of previously computed temperature related control inputs is provided in response to detected variations from a predetermined temperature reasonability criterion. Novel placement and orientation of system thermocouples facilitates achieving improved monitoring, detection and control.

Abstract: A brushless DC motor includes a rotor adapted to rotate about an axis and having a plurality of magnets for generating a magnetic flux; a stator having at least two coils through which an alternating signal is applied for rotating the rotor about its axis; and a reversible drive circuit for regulating the alternating signal through the coils and which includes first and second switching transistors for energizing the coils with the alternating signal, a rotational position sensing circuit for generating a position signal corresponding to the rotational position of the rotor, a rotational direction selecting circuit for producing a control signal corresponding to a desired rotational direction of the rotor, an NPN switch control transistor responsive to the position signal and control signal for alternately switching the first and second switching transistors so as to rotate the rotor in the forward direction, and a PNP switch control transistor in parallel with the NPN switch control transistor and responsive

Abstract: A motor drive system having a direct current, shunt motor utilized in a web coiling operation and operated in a tension control mode includes circuitry to automatically provide compensation for inertial effects of the drive and the web coil during periods of acceleration and deceleration.