387 results about "Shunt generator" patented technology

The display comprises an array of pixel circuits each comprising an emitter 1 in series with a current modulation transistor, and at least one address circuit, which integrates, for each column, a differential amplifier and a passive element preferably a resistive element, which cooperate with the current modulation transistors so as to form, during address phases in which the emitters are switched “out of the circuit”, a voltage-programmable current generator. After the address phases, thanks to a suitable switch, the emitters are switched “into the circuit” and supplied with the preprogrammed current. Such a display allows the image display quality to be inexpensively improved.

A light source and method for controlling the same. The light source utilizes a light generator that generates a light signal of a wavelength at an intensity that is set by a control signal. The control signal is controlled by a servo that monitors the light output of the light generator and compares the monitored value with a target value. When the target value is changed, the control signal is initially replaced by a predicted control signal based on the new target value rather than the error signal generated in the servo. This provides time for the servo to adjust to the new target value. In one embodiment, the control signal includes a periodic signal that switches between a value that causes the light generator to generate light of the wavelength and a second value at which the light generator does not generate light of the wavelength.

The invention relates to an air-gap field detecting device of an alternating-current generator, comprising a detecting coil and a signal detecting and processing circuit, wherein the detecting coil is arranged on a rotor of the alternating-current generator and surrounds one zone on the inner surface of the stator, and the induced voltage of the detection coil is relevant to the strength of an air-gap field in the zone surrounded by the detecting coil, as well as the distribution condition and the changes of the air-gap field; the signal detecting and processing circuit is connected with the detecting coil and used for detecting and processing the induced voltage of the detecting coil; the signal detecting and processing circuit can be used for detecting and processing the fundamental waves or the harmonic waves of the induced voltage of the detecting coil, or detecting and comparing the induced voltages of different detecting coils, and the detection and processing result can be used for the monitoring of the states of the generator, including the faults of stator and rotor windings, the decentraction of a stator and a rotor, axial and opposite shift of the stator and the rotor, magnetism loss, overload, external short circuit and circuit breakage and the like; and the detection and processing result of signals can also be used for the operation control of the generator.

The rotary machine comprises a rotary shaft (2) supported by first and second radial magnetic bearings (5, 6) that are electrically controlled by a control device (13), said rotary shaft being fitted with an axial abutment device (100) comprising a rotor formed by a disk (101) secured to the rotary shaft (2) and interposed between first and second stators (102, 104) formed annularly around the rotary shaft and each including at least one annular coil (103; 105) controlled electrically by a system for servo-controlling the axial position of the rotary shaft. The stator (104) of the axial abutment device (100) further comprises a secondary induction circuit (106), and the disk (101) secured to the rotary shaft comprises a primary induction circuit (107) so that during rotation of the shaft, electricity is excited in the secondary induction circuit in order to supply energy to the radial magnetic bearings.

A system interconnection control section 7 interconnects and parallels off an output from a generator 1 with a system 9, and supplies an output from the generator 1 to a load 10. A selection switch 24 that selects operation modes of the generator 1 is provided. The operation modes are an interconnected operation mode to shut down operation of the generator 1 and an isolated operation mode to operate the generator 1 after disconnecting the output from the generator 1 from the system, when a power of the system 9 has been stopped. During a power failure, the selection switch 24 is switched to select a start and a shutdown of an isolated operation.

Bandgap reference voltage generation circuit in semiconductor memory device includes a first current generator configured to generate a first current proportional to a change of a temperature by using temperature characteristic of a diode-connected MOS transistor, a second current generator configured to generate a second current inversely proportional to the change of the temperature by using the temperature characteristic of a diode-connected MOS transistor and a summation unit configured to mirror and sum the output currents of the first current generator and the second current generator, and output a reference voltage.

A current generator includes a thermistor configured to receive an input current, a reference resistor of a value substantially corresponding to a resistance of said thermistor at a reference temperature, a current mirror configured to generate a mirrored current proportional to said input current, a feedback circuit configured to generate an output compensation current proportional to a difference between voltages on said reference resistor and on said thermistor, and a first adder configured to force through said reference resistor a difference current between said mirrored replica current and said output compensation current.

In a burner for operating a combustor, the former consists essentially of a rotation generator (100), a transition piece following the rotation generator, and a mixing pipe following this transition piece. Transition piece and mixing pipe form the mixing section (220) of the burner and are located upstream from a combustion chamber (30). In the lower part of the mixing pipe is located a pilot burner system (300) which creates, among other things, a stabilization of the flame front, in particular in the transient load ranges, while minimizing pollutant emissions. A sensor (400) installed in the burner detects a flashback of the flame (80), whereupon the fuel quantity of this flame is at least temporarily reduced and at the same time the fuel quantity for the pilot burner is increased in such a way that the total fuel quantity and thus the turbine output remains constant. This measure prevents a destruction of the burner.

A method and a device are provided for providing a supply voltage for the consumers of a vehicle electrical system, using generator units connected in parallel. The measurement voltage inputs and the monitor outputs of the controllers of the generator units are used in the initialization phase for the assignment of master or slave function, as well as for address assignment if warranted, and during later parallel operation are used to bring the degree of utilization of the generators of the generator units connected in parallel into agreement.

Exemplary systems, methods and apparatuses for providing dimming in a distributed solid-state lighting system are disclosed. An exemplary dimming signal generator is coupleable to a controller or a current generator for a plurality of LEDs, and includes a first resistive voltage divider to sense an input DC voltage; a current sensor to sense a current level of the plurality of LEDs; a first operational amplifier to compare the sensed input DC voltage to a reference voltage level and to provide a comparator output signal; and a current path to combine the comparator output signal with the sensed LED current level to provide a combined signal for current level feedback for control of the LED current level. The dimming signal generator may optionally include other components to generate a PWM signal and also to provide a resistive network to divert LED current in response to the comparator output signal.

The present invention relates to a multiple output boost DC-DC power converter generating two, three or more separate DC output voltages, and to a multi-level power inverter and an alternating current generator both employing the multiple output boost DC-DC power converter.

An analog variable-frequency controller includes a first current generator, a second current generator, a clock generator and a light/heavy load selector. The first and second current generator receive a load current signal and then output a first voltage signal and a second voltage signal, respectively. The clock generator generates a corresponding switching frequency according to the first voltage signal or the second voltage signal. The light/heavy load selector, connected with the first current generator, the second current generator and the clock generator, receives a control signal for controlling the clock generator to receive the first voltage signal or the second voltage signal. The abovementioned controller is implemented by an analog circuit, which has a lower circuit complexity, lower cost and is easy to be integrated into a switching converter.

A compensated current generator includes a first current source and a second current source coupled in series. The first and second current sources have temperature coefficients with opposite signs to produce a temperature compensated current. The first current source may be a peaking current source biased by a bias signal to operate a peak of its transfer characteristic curve to enhance power supply rejection. An associated method is also provided.

A rotor for a vehicular alternating current generator has a relief space portion formed between axial holes of a pair of pole cores and a shaft for receiving therein a plastically deformed portion produced when the shaft is press-fitted in the axial holes of the pole cores. The relief space portion is located adjacent to a pair of closely contacting inner end faces of the pole cores so that the plastically deformed portion is let to move into a radially outward direction rather than further continuing movement in an axial direction within the relief space portion. The plastically deformed portion is thus prevented from entering between the inner end faces of the pole cores.

A drive current generator that supplies a desired drive current to an LED has: a drive transistor that is connected in series between one end of the LED and a ground; a first current control portion that performs conductivity control of the drive transistor in such a way that a monitoring voltage commensurate with a current flowing through a reference resistor equals a predetermined reference voltage, and that produces an intermediate current that behaves in the same way as a drive current; a current mirror portion that produces a mirror current commensurate with the intermediate current at a given ratio, and that feeds the mirror current thus produced back to the reference resistor; and a second current control portion that keeps the ratio of the drive current to the intermediate current at a given value. With this configuration, it is possible to supply a desired drive current to the load while minimizing the reduction in efficiency.

A device includes a light emitter, a current sensing resistance, a current generator, and detection circuitry. The current generator is connected to the light emitter and to the current sensing resistance. During a normal operating mode of the device, the current generator regulates current flow through the light emitter. In a test mode, the current generator regulates current flow through the current sensing resistance. The detection circuitry, during the test mode, detects when current flow through the current sensing resistance is outside an expected range.

The invention provides a generator test system which comprises a control unit, a detection unit, a tested generator, a direct current motor and a direct current motor driving unit. The system is characterized in that: the system also comprises a load generator, wherein the tested generator, the load generator and the direct current motor are in coaxial connection; output of the tested generator and input of the load motor are connected to provide electric energy input for the load generator; the direct current motor driving unit connects with the direct current motor and is used for driving the direct current motor; the detection unit connects with the tested generator and is used for detecting a parameter of the tested generator; the control unit is used for sending a control signal to the direct current motor driving unit in order to control running of the direct current motor. According to the test system, a power feedback method is employed, electric energy generated by the tested generator in a test process is sent to a generator which is taken as a load of the tested generator, environmental protection is facilitated, system composition is simplified, thus a failure rate is reduced, test accuracy is raised, test cost is reduced, and enterprise competitiveness is enhanced.

The invention, which belongs to brushless generator field, discloses a double excitation-winding compound-excitation double-salient brushless direct-current generator. The double excitation-winding compound-excitation double-salient brushless direct-current generator comprises: a double excitation-winding compound-excitation double-salient motor, a rectification circuit and a filtering capacitor. An armature winding of the double excitation-winding compound-excitation double-salient motor, the rectification circuit, a first set of excitation winding of the double excitation-winding compound-excitation double-salient motor and the filtering capacitor are successively connected in series. A second set of the excitation winding of the double excitation-winding compound-excitation double-salient motor is connected with a direct current excitation power supply. Because of a self-excitation effect of the first set of the excitation winding, a generator voltage regulation rate is low and excitation power needed by control output is low. The generator is especially suitable for independent power supply systems, such as an electric automobile vehicle power generation system, an airplane power generation system and the like.