Abstract: A method and system control the adding or dropping of phases in a multiphase voltage regulator. The regulator has an efficiency and this efficiency of the regulator is calculated for a given number of phases being activated from an output voltage, input voltage, output current, and duty cycle of the regulator. The efficiency of the regulator is also calculated if a phase is added using the derivative of the duty cycle as a function of the output current. The efficiency of the regulator is further calculated if a phase is dropped using the derivative of the duty cycle as a function of the output current. From these operations of calculating, a phase is either added, dropped, or the phase is maintained at its current value to thereby optimize the efficiency of the regulator.

Abstract: In a power converter apparatus, such as an uninterruptible power supply, a phase reference signal is generated responsive to a DC voltage on a DC bus. A magnitude reference signal may be generated responsive to a phase current of an AC bus and/or the DC voltage on the DC bus. Power is transferred between the AC and DC busses responsive to the phase reference signal and the magnitude reference signal. Generation of the phase reference signal may include generating a DC voltage error signal responsive to the DC voltage on the DC bus, generating a phase offset signal responsive to the DC voltage error signal, and generating the phase reference signal responsive to the phase offset signal. Generation of the magnitude reference signal may include generating a volt-amperes reactive (VAR) error signal responsive to the phase current and generating the magnitude reference signal responsive to the VAR error signal.

Abstract: In various embodiments, a phase current sampling apparatus (300, 600, FIGS. 3, 6), an electric motor drive system (100, FIG. 1), and a motor vehicle (1200, FIG. 12) include switching circuitry adapted to receive first and second phase current waveforms. The switching circuitry provides the first phase current waveform during at least two offset sampling instants, and provides the second phase current waveform during a reference sampling instant. An analog-to-digital converter is adapted to sample the first phase current waveform at the offset sampling instants, and to sample the second phase current waveform at the reference sampling instant. An embodiment of a method for regulating phase current waveforms includes an analog-to-digital converter generating samples of a first phase current waveform at sampling instants that occur before and after a reference sampling instant, and generating a sample of a second phase current waveform at the reference sampling instant.

Abstract: Provided is a welding system and method for controlling a welding system with an improved waveform. In accordance with one aspect of the present invention, a welding system waveform is calibrated such that the welding transfer regularly occurs during short circuits, comprising applying a voltage and a current to a welding electrode, applying an increased voltage and an increased current to the welding electrode, increasing the current to the welding electrode when a short circuit is detected, and maintaining the increased current applied to the welding electrode until a desired time expires after the short circuit is detected or until the short circuit clears, whichever occurs first.

Abstract: The invention relates to a method for power control of an electric motor, in particular a motor for driving the suction fan of a vacuum cleaner connected to an AC mains power supply. The power control is effected by varying the phase angle of the electric alternating quantity supplied to the motor by the use of semiconductor switches. AC power supplied to the motor is switched by using different delay times for the switching in each half-period of a full AC period to suppress odd harmonics, particularly the third harmonic of the mains power line frequency. Half-periods of a full period are mirrored in the next consecutive full period in order to suppress even harmonics, particularly the second harmonic of the mains power line frequency. A set of delay times t1 and t2 are defined and selected to be used in further avoiding critical delay time areas for harmonics and minimize the generation of vibrations.

Abstract: A vacuum apparatus which can easily regenerate plasma is provided. A matching box used in the vacuum apparatus can vary the impedance thereof by varying the magnitudes of the inductance of variable inductance elements. Controlling the magnitude of direct current makes it possible to control the magnitudes of inductance of the variable inductance elements so that it is possible to carry out matching operation at high speed.

Abstract: The present invention is related to a method for measuring the instantaneous value of a monophase AC voltage signal Ve, comprising the steps of: applying said voltage signal Ve to a first input of a phase comparing circuit and a reference signal to a second input of said phase comparing circuit, in said phase comparing circuit deriving from the phase difference between said reference signal and said voltage signal Ve a correction signal and outputting said correction signal, filtering said correction signal, using said filtered correction signal to adjust said reference signal, when the phase difference between said reference signal and said voltage signal Ve is cancelled, determining the instantaneous value of said voltage signal Ve.

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: A phase activation control system for a multiphase DC/DC converter including an amplifier circuit and enable logic. The converter includes a first phase circuit providing a first PWM signal and has a reduce input for reducing duty cycle of the first PWM signal. The converter further includes a second phase circuit providing a second PWM signal and having an enable input and an increase input for increasing duty cycle of the second PWM signal. The amplifier circuit has an enable input, a current sense input for sensing output current of the converter and an output providing an adjust signal. The adjust signal is provided to the reduce input of the first phase circuit and to the increase input of the second phase circuit. The enable logic receives a phase enable signal and enables the amplifier circuit and the second phase circuit.

Abstract: A phacoemulsification system includes a phacoemulsification handpiece including a cutting tip ultrasonically vibrated by an ultrasonic transducer. A power supply is provided for driving the ultrasonic transducer at a resonant frequency of the transducer and cutting tip and varying power to the transducer, in response to loading of the cutting tip, by phase shifting drive signals to the resonant converter which supplies power to the transducer.

Abstract: A circuit for controlling two switches assembled in anti-parallel, comprising in series between two terminals of the anti-parallel assembly, two identical control stages respectively dedicated to each switch and between which is interposed a common impedance setting a phase angle for the turning-on of the switches, each stage comprising: a controllable current source for providing a current to a control electrode of the concerned switch; a capacitor for storing a supply voltage of at least the current source; an element of activation/deactivation of a the current source according to the voltage across the stage capacitor; and an assembly for discharging the capacitor.

Abstract: A reliable strobe power supply is disclosed that provides requisite light energy for emergency uses without causing EMI problems. A two phase dual flyback power converter operating in transitional mode is disclosed containing a microcontroller that maintains a 180 degree displacement between the two phases by enabling a small, variable dead time between the cessation of stored energy in the flyback transformers and turn-on of the associated power switching transistor for one or the other phases. The power supply is capable of detecting a fault (neoning) and automatically correcting the condition by incrementing the flash capacitor charge off-time delay. The power supply is also capable of tolerating defective (persistently neoning) strobe tubes that cause an inordinate delay in capacitor charging by turning them off.

Abstract: An induction generator power supply comprises a prime mover, an induction generator operably connected to the prime mover and having a generator output, and a phase shift circuit, having a circuit input and a circuit output, the circuit input connected to the generator output. The power supply also comprises an AC to DC converter, having a converter input and a converter output, the converter input connected to the circuit output, and an energy reservoir having a reservoir input connected to the converter output.

Abstract: A plurality of single-phase synchronizing converter automatically synchronize on a peer-to-peer basis. Each synchronizing converter is configured as a DC-to-DC converter. The synchronizing converters operate in parallel as a multi-phase converter. A common bus between the synchronizing converters includes a sync line and a common phase control line. Proper phasing automatically occurs when power is applied, and the phasing changes automatically as converters are added or removed. When the system powers up, the converters arbitrate for phase position. The phasing positions are random, but the phasing is relatively symmetrical regardless of the number of phases. Preferably, a hot-swappable converter module can be plugged into any location of a parallel multiphase bus to produce a common output voltage. When an additional module is plugged in, the converters readjust their phases to maintain phase symmetry. Preferably, each module shares a substantially equal portion of the output load.

Abstract: A plurality of single-phase synchronizing converter automatically synchronize on a peer-to-peer basis. Each synchronizing converter is configured as a DC-to-DC converter. The synchronizing converters operate in parallel as a multi-phase converter. A common bus between the synchronizing converters includes a sync line and a common phase control line. Proper phasing automatically occurs when power is applied, and the phasing changes automatically as converters are added or removed. When the system powers up, the converters arbitrate for phase position. The phasing positions are random, but the phasing is relatively symmetrical regardless of the number of phases. In one embodiment, a hot-swappable converter module can be plugged into any location of a parallel multiphase bus to produce a common output voltage. When an additional module is plugged in, the converters readjust their phases to maintain phase symmetry. In one embodiment, each module shares a substantially equal portion of the output load.

Abstract: There has been a problem in that when an electric power supplier carries out demand control by discount or the like, it cannot suitably estimate an amount of demand control and a cost for it. Therefore, an object of the invention is to provide a power supply plan making support method such as enables support upon making a generator operation plan and a power purchase plan by considering power demand control. A predicted cost for demand control is expressed by an equation to enable a concept of demand control to be easily reflected in equations for calculation for presenting information for an electric power supply plan, thereby enabling presentation of a suitable amount of demand control and a necessary cost.

Abstract: A phase shifter is disclosed in which parasitic elements in a microelectromechanical system (MEMS) switch are designed and utilized to provide a predetermined phase shift. In one embodiment, a circuit containing three MEMS switching modules, each of which includes a pair of series-coupled reactances is described. The first reactance is determined by an inductor, the second by a capacitor representing the MEMS switch contact in either the up or down positions, and wherein the capacitive reactance is greater than the inductive reactance for the MEMS switch contact in the up position and less than the inductive reactance for the MEMS switch in the down position. The three MEMS switching modules are configured such that a switched high pass/low pass phase shifter topology can be realized with the appropriate actuation of the MEMS switch contacts.

Abstract: A phase shifter is disclosed in which parasitic elements in a microelectromechanical system (MEMS) switch are designed and utilized to provide a predetermined phase shift. In one embodiment, a circuit containing three MEMS switching modules, each of which includes a pair of series-coupled reactances is described. The first reactance is determined by an inductor, the second by a capacitor representing the MEMS switch contact in either the up or down positions, and wherein the capacitive reactance is greater than the inductive reactance for the MEMS switch contact in the up position and less than the inductive reactance for the MEMS switch in the down position. The three MEMS switching modules are configured such that a switched high pass/low pass phase shifter topology can be realized with the appropriate actuation of the MEMS switch contacts.

Abstract: An apparatus and a method for controlling a converter of electronic power supply energy embodied for example as a boost converter or as a boost converter with a power factor correction (PFC) or being used as a DC to DC converter that is running in a discontinuous mode and which is using an equation to calculate the point of time of the zero current state of the storage inductor based on the ON time of the shunt switch and the voltages at the source and the load side. This method achieves a maximum power transfer by recharging of the storage inductor right after the zero current state is reached. The accuracy of the voltage measurement is increased by calibration of the source and load voltage dividers. Minimizing distortion and harmonics is achieved by a fine adjustment of the energy transfer through fine-tuning of the pulse width of the switch overcoming the limitations of discrete time steps in clocked digital systems by toggling between neighboring ON time values of the switch.

Abstract: In low-power AC networks, it is desirable when a load is connected, for example an arc furnace or a vehicle, to know the load capacity of the AC network in order to avoid undesirable drops in the network voltage U.sub.N. To this end, load voltage signals which are proportional to the amplitude of a load voltage U.sub.L are detected at the point of the load L at a 1st measurement time which can be predetermined and at a 2nd measurement time which can be predetermined and is later. At the same time, load current signals are detected which are proportional to the amplitude of a load current I.sub.L. Furthermore, a phase difference .DELTA..phi. is determined, which is obtained with reference to the phase angle of the network voltage U.sub.N at the 1st measurement time. These measurements are used as the bases to calculate a magnitude of the network impedance of the AC network and the network phase angle .phi..sub.N between the network voltage U.sub.N and the network current. A maximum possible power P.sub.

Abstract: The present invention relates to an electronic switch system for controlling AC power to a load. The switch has ON, OFF and RAMP down modes that can be selected by means of momentary touch switches. When put into the RAMP down mode, the power to the load decreases slowly at a gradual continuous uninterrupted predetermined rate. This switch system has particular utility in brightness control of lamps. It has been found that the use of a lamp controlled by an electronic switch of the present invention often will induce sleep for people that have difficulty going to sleep, particularly young children and older persons. Thus the electronic switch system and devices embodying this system are particularly useful in a method to induce sleep.

Abstract: A phase control system has a stable timebase phase reference generated by an internal phase reference generator. The control includes a method for estimating and compensating phase distortion when an inductive load is driven by an AC voltage source having significant line impedance. A digital phase comparator estimates a phase error between the timebase phase reference and the voltage source. At the initialization of the phase control system, the phase reference clock period is frozen for a fixed number of cycles to determine an average phase error due to the phase distortion caused by the line impedance. The estimated phase error is then corrected to account for the average phase distortion error.

Abstract: A method and arrangement for controlling the output of electrical consumers connected to ac line voltage, especially of electric motors and the like, in which the output is changed by changing the phase control of the electric alternating magnitude supplied to the consumer. The extent of the firing angle determining the extent of the phase control is varied toward larger or smaller values around the given reference value of the firing angle, which reference value corresponds to the desired power consumption, so that asymmetry of the firing angle is produced with respect to time between two successive full waves, whereby odd-numbered harmonics are sharply reduced as even-numbered harmonics slowly increase.

Abstract: An EL lamp is charged to a first polarity with a series of high voltage pulses, discharged at a controlled rate, charged to a second polarity with a series of high voltage pulses, and discharged at a controlled rate, thereby producing an alternating current through the lamp. A flyback circuit provides the high voltage pulses. The polarity of the pulses is reversed periodically at a low frequency and the EL lamp is prevented from discharging through the flyback circuit by a phase shift circuit that produces a discharge pulse in advance of each change of polarity of the high voltage pulses. The discharge pulse interrupts the high voltage pulses and discharges the EL lamp through a constant current load.

Abstract: A transmission line power controller for controlling the flow of electric power in an alternating current three-phase transmission system is described. The power line controller includes a parallel inverter connected to a series inverter through a dc link. The parallel inverter is connected in shunt to the transmission system through a shunt transformer. The series inverter is connected in series with the transmission system through a series transformer. A transmission line power control circuit is used to specify a desired real power demand and reactive power demand for the transmission system. The power control circuit processes this information along with a transmission line voltage vector and a transmission line current vector to produce a voltage source reference signal that is applied to the series inverter. In response to the voltage source reference signal, the series inverter produces an injected voltage vector into the transmission system.

Abstract: An emergency power system is connected between an AC voltage source and a load. The emergency power system ensures a stable voltage on the output, even if the AC voltage received from the AC voltage source is irregular or is interrupted briefly. The emergency power system includes an AC/DC converter coupled between the load terminals and an AC regulator positioned between the AC voltage source and the load. The AC/DC converter is coupled to a chargeable battery and serves as a charging rectifier for the battery in normal operation and as an inverter in emergency operation, the battery voltage being converted to AC voltage on the output of the emergency power system. The AC regulator is built as a controllable current generator supplying on its output an AC current which is in phase with the AC voltage received from the AC voltage source. Irrespective of the energy direction through it, the AC/DC converter maintains the predetermined AC voltage (V.sub.

Abstract: A phase-shifting interconnection apparatus for interconnecting respective phase lines of first and second synchronous polyphase AC networks, includes for each pair of respective phase lines subjected to an interconnection a pair of circuit branches in parallel, having first and second common branch points provided with connecting means for connecting respectively the branch points to the respective phase lines, the circuit branches including respectively inductive and capacitive susceptances; and series transformer for phase-shifting a voltage applied to at least one of said susceptances, the series transformer including at least one primary winding having at least a portion connected in series with the at least one of the susceptances, and at least one secondary winding having at least a portion adapted to receive an excitation voltage derived from the AC networks, the excitation voltage having a phase angle with respect to a phase voltage provided by one of the respective phase lines, whereby, in operation,

Abstract: An out of phase detecting apparatus according to the present invention includes a measurement unit for measuring an effective power and a current effective value at a tie point of power systems at a predetermined cycle, a power trend detection unit for detecting a trend of the effective powers measured in sequence by the measurement unit, a current trend detection unit for detecting a trend of the current effective values measured in sequence by the measurement unit, a power level determination unit for determining a relationship in strength between each of the measured powers and a steady effective power P.sub.0 obtained when the power systems are in a steady state, and an out of phase detection unit for detecting whether an out of phase condition occurs in the power systems based on the trend of the measured effective powers, the trend of the measured current effective values, and the relationship in strength between the steady effective power P.sub.0 and each effective power.

Abstract: A phase control circuit for operating a phase shift in accordance with a control voltage comprises four differential circuits, two of which form a multiplier circuit for providing a basic function for a phase shift operation of the phase control circuit, and the rest of which cancel variations in amplitude generated during the phase shift operation. The amplitude compensation is accomplished by a construction in which a ratio of an emitter area of a first bipolar transistor in each of the differential circuits to an emitter area of the second bipolar transistor in each of the differential circuits is set at a value between 2 and 3. Alternatively, the amplitude compensation is provided by a level shift circuit providing an offset voltage in the control voltage supplied to two of the differential circuits.

Abstract: A device runs a precheck of an inductive load for an overload prior to swhing on to supply mains. For this purpose, following switching-on for a load precheck, initially a phase limited voltage signal is applied to the load, whereby the voltage signal duration gradually increases. With the start of each application of voltage, the active current is measured in a narrow time window. If it does not exceed a predetermined active current limit at an application of a specific effective voltage, the load is switched to the mains. Otherwise, the switch-on process is cut off. This switching-on process avoids a high taxing of the mains in the event of a short circuit or an overload. The active current window begins with the application of voltage to the load. At a different time than this time window, a further measurement window is provided for the reactive current, whereby this measurement window begins with the zero crossing of the alternating voltage.

Abstract: A firing controlled scheme including a method and apparatus for vernier operation of a shunt-connected thyristor-controlled capacitor (STCC) uses phase controlled firing of the thyristors based on monitored line voltage, monitored thyristor current, and a thyristor current command to vary the effective reactance of the capacitor. The STCC includes a capacitor and surge inductor connected in shunt across a power transmission line via a thyristor switch. A vernier controller predicts an upcoming firing angle based on the above parameters and switches the thyristor circuit to partially conduct pulses of thyristor current at different amplitude levels depending upon the commanded firing angle. By varying the firing angle, variable inductive and capacitive reactive power can be selectively delivered to the transmission line.

Abstract: The monitoring and control system of the present invention provides a distributed intelligence, data acquisition and control system which collects and analyzes large amounts of data representing power usage from a power distribution substation. Using a Discrete Fourier Transform, the system provides accurate tracking of the primary frequency of the voltage and current waveforms in the power equipment, and determines the relative phase between the voltage and current waveforms. The system provides real time monitoring of power usage and real time control of various functions in the substation.

Abstract: An automatic power factor correcting device for correcting the power factor of a load connected to a power line having a plurality of confuctors including a neutral conductor, a power line interface circuit for interfacing the device with the power line, a phase sensing circuit connected via the interface circuit to at least two of the conductors for sensing a phase shift between voltage and current in the two conductors. It further includes a phase correction circuit with a plurality of weighted capacitors, and capacitor connecting means having a control input connected to the phase sensing circuit for connecting at least one of the weighted capacitors to the power line for correcting the phase shift on the two conductors.

Abstract: An AC system having, for example, a voltage source, an inductance and a load has connected thereto an apparatus for controlling the phase and amplitude of the voltage of the system. The instantaneous current and voltage in the AC electrical system are measured and power measurements derived therefrom. The power measurements may be instantaneous real and imaginary power, instantaneous active and reactive power, or active and reactive power averaged over less than one cycle. The power measurements are then used to derive phase related control values, on the basis of which control signals are generated to a converter. The action of the converter in accordance with the control signals thus controls the amplitude and phase of the voltage. By use of power measurements, it is not necessary to measure the phase of the voltage of the AC system.

Abstract: An advanced static VAR (volt ampere reactive) compensator (ASVC) system for coupling with and compensating a transmission line of a power system includes an ASVC controller. A voltage-sourced inverter has an AC side coupled through a series inductance to the transmission line, and a DC side coupled to a capacitor. By monitoring the DC side voltage, two line-to-line voltages and two line currents between the series inductance and the transmission lines, the ASVC controller determines an instantaneous reactive current component of the line current. The ASVC controller adjusts the phase angle of the inverter AC output voltages to compensates the transmission line by negating the instantaneous reactive current, and thus, the undesirable instantaneous reactive power on the transmission line. A method is also disclosed of compensating the instantaneous reactive power flowing over the transmission line.

Abstract: In an electrical supply network containing a generator, critical fluctuations in real power can occur. The load angle of the generator is representative of these fluctuations. The present invention provides a method which measures the real and reactive power flow, the current and the voltage on a line to the generator and feeds these measured values along with reactance values Y.sub.L and Y.sub.Q of the generator and line to a computing device. The computing device determines an output signal .delta. which represents the load angle of the generator and fluctuations in real power. The output signal .delta. is provided to an indicating device and/or a reactive power compensator.

Abstract: A control system for power delivered to an inductive load includes automatic control with a manual override for emergency situations. The system monitors the power delivered to the load and varies the power delivered to the inductive load by controlling the phase difference between the voltage and current delivered to the load. Feedback to the control system automatically controls the phase difference between voltage and current in response to the measured power delivered to the load. Provision is made for introducing an external signal into the feedback circuit, whereby the external signal supersedes the automatic control of the power delivered to the load.

Abstract: A phase shifting circuit includes: a pair of input terminals; a pair of output terminals; a variable gain amplifier and an active alternating current integrator, connected in series between the input terminals and the output terminals; and a control circuit for controlling the gain of the amplifier in dependence on the voltage between the input terminals and the voltage between the output terminals so as to maintain the amplitude of the voltage between the output terminals substantially equal to the amplitude of the voltage between the input terminals. The phase shifting circuit exhibits low variation of phase shift with input signal frequency.

Abstract: An improvement in a device for the combination of two alternating signals of the same frequency in which two microwave combination devices are associated with two phase shifters to combine the two signals. By coupling the two phase shifters according to a particular coupling relationship, the two alternating signals are combined regardless of the load presented at one of the these two signals.

Abstract: A compact, liquid cooled, ferrite phase shifter is capable of handling high power microwave signals without thermally stressing the ferrite core. The ferrite core is mounted on spacers inside of a hermetically sealed wave guide filled with a thermally conducting fluid. Heat transfer from the core to the housing is symmetrical thereby eliminating or minimizing thermal bending stresses on the phase shifter. Heat from the core is also coupled through the fluid to the phase shifter window for deicing the window.

Abstract: A high frequency link power converter apparatus includes a power source, a circulating current type AC-AC converter having an output terminal connected to the power source, a high frequency phase-advancing capacitor connected to an input terminal of the AC-AC converter, a phase controller for controlling a firing phase of the AC-AC converter, an external oscillator for supplying phase reference signals to the phase controller, a first circuit for controlling a crest value of voltages applied to the phase-advancing capacitor, a second circuit for detecting a phase difference between the reference signals and the voltages applied to the phase-advancing capacitor, and a third circuit for controlling the phase difference, so that the magnitude of the phase difference becomes substantially zero.

Abstract: An electric power converter, in which a plurality of converters convert a first electric power having a first frequency into a second electric power having a second frequency, and the second electric power is supplied to a load such as an electric motor, and in which a correction controller changes a reference voltage to generate reference voltage signals to be supplied to the converters in order to shift firing phase angles of the converters, thereby preventing a generation of higher harmonics of integer orders of the first electric power.

Abstract: A variable dual phase shifter for simultaneously varying the phase shifts in two signal paths by equal and opposite amounts comprises two 90.degree. hybrids in the respective signal paths, and a pair of substantially identical transmission lines connecting output ports of one hybrid to output ports of the other. A number of variable-impedance radio-frequency devices, which are preferably p-i-n diodes, are connected to the transmission lines at positions spaced apart along the length of the lines, the positions on one line corresponding to those on the other line. The impedances of the devices are controlled to create a reflective termination at a selected position on one line and a reflective termination at the corresponding position on the other line, so that the phase shift applied to each signal is determined by the distance of the reflective termination from the respective hybrid. The devices may be arranged in pairs, each device of a pair being coupled to a respective one of the transmission lines.

Abstract: A control system for controlling the load of an AC motor/generator of secondary AC excitation type connected to a power system in parallel to at least a synchronous machine. The AC motor/generator has the secondary excitation winding thereof controlled in the amount of excitation so as to generate an output in accordance with an external output command. In the case of variation of power flow between the power system and the synchronous machine, the output command is corrected in accordance with the variation, and the amount of the secondary excitation is controlled by the corrected output command, whereby the variation of power flow between the power system and the synchronous machine is absorbed by the AC motor/generator thereby to prevent the synchronous machine from stepping out.

Abstract: An ultrasonic generator for providing power to a bonding apparatus having a bonding horn which is brought into contact with respective conductive pads and which carries a wire to be dispensed for interconnection therebetween includes a circuit for applying a voltage at an ultrasonic frequency to the bonding horn to produce a bonding current in the horn, and a monitor for monitoring the bonding current applied to the bonding horn. A circuit is provided for maintaining a zero phase difference between the applied voltage and the monitored current. In addition, a circuit is provided for continuously monitoring and controlling the current which is delivered to the bonding horn to produce a current waveform of a predetermined controllable pattern.

Abstract: A programmable slewing power supply is used to drive microwave phase shifters according to a command signal from a system controller using: a Milberger converter; a power source; a rectifying circuit; two differential amplifier circuits; and two comparator amplifier circuits. The Milberger converter outputs a combined square wave which it produces by combining two independent square waves which add or cancel. The power source receives the combined square wave and outputs: a reference voltage, a positive voltage signal; and a negative voltage signal. The rectifying circuit produces a rectified command signal by rectifying the command signal from the system controller. The two differential amplifier circuits respectively measure the positive and negative voltage signals with respect to the reference voltage to produce a measured positive voltage signal, and a measured negative voltage signal.

Abstract: A phase controller of a type consisting of two magnetic contact units, a phase shifting mechanism for a thermal relay, a biasing circuit, a control circuit and a delay circuit, whereby phase shifting by the phase shifting circuit and three-phase currents, in coordination with the biasing effects due to the biasing circuit, alters the peak voltage of the alternating currents flowing past the phase-setting relay, to convert the state of the contacting points so as to incite the magnetic contacts in the phase conversion unit following a change in phase of the three-phase power source, thus maintaining the output end of the power source at a certain phase in a manner convenient and safe enough by all standards.

Abstract: A power factor controller for alternating current/direct current drilling rigs is provided which utilizes a uniquely controlled, unloaded, over-excited generator to provide reactive power to maintain the rig's power factor within prescribed limits during peak demand operations.

Abstract: A power factor controller for alternating current/direct current drilling rigs is provided which utilizes a uniquely controlled, unloaded, over-excited generator to provide reactive power to maintain the rig's power factor within prescribed limits during peak demand operations.

Abstract: A phase synchronizer for obtaining a signal which is phase synchronized with respect to another signal which has passed through a transmission system after originating at a signal source, the phase synchronizer comprising a variable phase shifter responsive to the output signal of the signal source for shifting the phase thereof in response to a control signal applied thereto; a phase comparator responsive to the signal which has passed through the transmission system and the output signal of the variable phase shifter to provide an output signal indicative of the phase difference between the two signals applied thereto; a low-pass filter responsive to the phase comparator output signal to provide the control signal for the variable phase shifter so that the phase of the output signal of the variable phase shifter follows the phase of the transmission system output signal.