48results about How to "Achieve optical isolation" patented technology

The invention belongs to the technical field of electric power detection and provides a photoelectric AC / DC voltage transducer based on the Pockels effect. The photoelectric AC / DC voltage transducer is not affected by environment temperature change, measurement precision is high, signal transmission is convenient, safety performance is high, power supply is not needed at a measurement point, and optical fiber signal transmission is immune to electromagnetic interference. The photoelectric AC / DC voltage transducer comprises a laser source, a transducer component, transmission fiber, a photoelectric detector and a backward-stage signal processing system, wherein the transducer component comprises a laser collimator I, a polarizer, a 1 / 4 wave plate, a crystal, an analyzer and a laser collimator II which are arranged along an optical path in sequence, the crystal is a cuboid, the length direction of the crystal is the light passing direction, the upper surface and the lower surface, perpendicular to the light passing direction, of the crystal are plated with metal layers serving as detection electrodes, the metal layers are used for loading voltage to be measured, the voltage direction is perpendicular to the light passing direction, and the backward-stage signal processing system obtains the voltage to be measured through a signal output by the photoelectric detector.

The invention relates to an optical electric galvanometer, based on Micro-Electronic Mechanic System (MEMS). It is characterized in that: it use micro mechanical technique to prepare the screw coil MEMS torsion micro lens; it can avoid amplify circuit, that directly inputting the tested current or low-frequency weak current into driving coil, to be arranged in the strong magnetic field generated by external permanent magnet; the driving coil drives the micro lens to deflect from original position by the torque generated by Lorentz force; it uses dual optical fiber collimator to test the characters that sensitive to the angle; according to the relationship between the optical signal loss and the torsion angle, via optical electric conversion and signal processing, attaining the current value. The invention can avoid amplify circuit at the input end, to attain amp level and pF level, to overcome the defects of noise disturb and excursion when amplifying the micro weak current signal. And it can realize the optical electric separation at input and output ends synchronously, with small volume, simple structure, lower cost and better anti-vibration ability.

The invention discloses a magnetic field sensor based on a silicon-based micro-ring resonator. The magnetic field sensor comprises a silicon substrate, a silicon dioxide layer, a direct waveguide, a ring waveguide and a magneto-optic film. By applying an external magnetic field outside the magneto-optic film, the dielectric constant of a magneto-optic material is changed, an output harmonic peak of the magnetic field sensor based on the silicon-based micro-ring resonator drifts, and magnetic field measurement is realized. The magnetic field sensor has the characteristics of high stability, size miniaturization, high electromagnetic interference resisting ability and low manufacturing cost.

The invention discloses a production technique of single crystal silicon nano film for nanometer photon technology. After clean and bake the insulator upper silicon plate of thickness of several to hundreds nanometer, joint the basal plate with one side of top layer silicon while removing the bottom silicon layer, acquiring single crystal silicon nano film. Single crystal silicon nano film produced with above technique has various thickness from several to hundreds nanometer, with a highly uniform thickness. There is enough thickness for light insulation on the lower light restrain layer and it is available for nano silicon photon device develop. According to actual needs the joint face of the silicon plate can take pre-process such as electrode placing or specified figure drawing.

The invention belongs to the field of mechanical equipment and particularly relates to a control system of an oil filter. The invention provides the control system of the oil filter, which occupies a small space and has high automation degree. The control system of the oil filter comprises a singlechip, an opening and closing module, a conversion module, a temperature sensor, a pressure sensor and a peripheral circuit; an input port of the opening and closing module is connected with an output port of the singlechip; the temperature sensor and the pressure sensor are connected with the singlechip by a converter; and a port of the peripheral circuit is connected with a port of the singlechip.

The invention provides a built-in partial discharge detecting device of a high voltage cable. The built-in partial discharge detecting device comprises an electrode, a fiber sensor, an extraction fiber, a photoelectric conversion module, an amplifier, a filter and a signal detecting module. The electrode is fixedly disposed on a semiconductive layer of a cable body. One end of the fiber sensor isconnected to the electrode and other end of the fiber sensor is connected to the input terminal of the photoelectric conversion module through the extraction fiber; and the output terminal of the photoelectric conversion module is electrically connected to the amplifier, the filter and the signal detecting module in sequence. In addition, the invention also proposes a mounting method thereof. Thefiber sensor collects a discharge signal of the cable through the electrode; the collected electrical signal is converted into an optical signal for transmission; the optical signal is transmitted tothe photoelectric conversion module through the extraction fiber to convert the optical signal into an electrical signal again; and then the electric signal is amplified and filtered by the amplifierand the filter in turn and then the processed signal is inputted into the signal detecting module to carry out partial discharge signal detection processing.

The invention provides a serial port expanding circuit of a dynamic management and control system. The serial port expanding circuit is electrically connected to RXD, TXD and I / O ports of a microprocessor. The serial port expanding circuit is characterized by being composed of an analog switch chip, a decoder chip, multiple first level switching circuits and multiple second level switching circuits, and expanding of input and output ports of the microprocessor is achieved; the first level switching circuits achieve switching of RS232 levels to TTL levels; the second level switching circuits achieve switching of the TTL levels to the RS232 levels. The invention further discloses a working method of the serial port expanding circuit. The working method involves expanding of TXD and expandingof RXD. By means of the serial port expanding circuit, expanding of the RXD and TXD ports of the microprocessor can be effectively achieved, and optocouplers are utilized to achieve switching of theTTL and RS232 levels; not only are signals reliably transmitted, but also the load capability can be improved; the serial port expanding circuit achieves optoelectronic isolation, is resistant to impact, and improves the anti-jamming performance of circuit expanding.

The invention discloses an all-light-path voltage measuring system based on an inverse piezoelectric effect and fiber bragg grafting. The system comprises a broadband laser light source, a voltage transducer reference unit, a voltage transducer sensing unit, a transmission optical fiber, a photoelectric detector, and a tail end signal displaying and processing system; laser sends a photosignal to an input end of the voltage transducer reference unit through the transmission optical fiber, and the input end of the voltage transducer reference unit is connected to the voltage transducer sensing unit; an externally-arranged voltage is arranged on the voltage transducer sensing unit; the voltage transducer sensing unit outputs a light intensity signal carrying signal information of a voltage to be detected; the light intensity signal is input to the photoelectric detector; the photoelectric detector converts the output light intensity signal into a voltage signal, and the voltage signal generates a numerical value of the detected externally-arranged voltage through the tail end signal displaying and processing system. The invention further discloses an all-light-path voltage measuring method based on the inverse piezoelectric effect and the fiber bragg grafting. The provided all-light-path voltage measuring system based on the inverse piezoelectric effect and fiber bragg grafting has the advantages of being passive, strong in capacity of resisting electromagnetic interference, wide in response frequency band, and good in power frequency response.

The invention provides a method and a device for measuring the propeller rotating speed of an underwater direct current brushless thruster. The device comprises an analog signal isolating unit, a digital signal photoelectric isolating unit, a frequency / voltage (F / V) conversion unit, a digital to analog conversion unit and a computer acquisition and computation unit, wherein a rotating speed digital pulse signal which is output by the direct current brushless thruster is subjected to analog signal isolation and photoelectric isolation and then converted into a rotating speed digital pulse signal of 0 to 5 V; the rotating speed digital pulse signal of 0 to 5 V is subjected to F / V conversion, and an analog voltage signal is output; the analog voltage signal is converted into digital quantity and further converted into a voltage value; the voltage value is subjected to V / F conversion, and the frequency of the rotating speed digital pulse signal is obtained; and the propeller rotating speed of the direct current brushless thruster is obtained by frequency / rotating speed conversion. The invention has the advantages of high anti-interference capacity and small in speed-measuring errors, analog signal and digital signal photoelectric isolation between a rotating speed measuring device and the direct current brushless thruster is realized, and the operation reliability of the direct current brushless thruster and the operation reliability of the measuring device are ensured.

The invention discloses a direct current motor braking device with controllable constant current and falling speed, and relates to the technical field of motor application. The power field effect transistor replaces a conventional dynamic braking resistor, and the equivalent resistance between the drain and the source of the power field effect transistor is adjusted in real time in a voltage control mode to realize the constant-current parking braking of the motor, so that the braking time is shortened to be less than 68 percent of that of the conventional dynamic braking mode. Under the condition of not changing hardware, the intelligent continuous control of the motor braking current and the potential energy load falling speed is realized by adopting a current and rotating speed two-stage closed-loop control technology and a digital signal processor. In order to increase the reliability of the control system, an optical isolator with double optical couplers as cores is designed and used for reliably isolating analog signals between a control stage and a power stage. The invention can realize the braking at the highest speed in the motor dragging process and the continuous regulation control of the falling speed of the potential energy load.

The invention relates to an optical electric galvanometer, based on Micro-Electronic Mechanic System (MEMS). It is characterized in that: it use micro mechanical technique to prepare the screw coil MEMS torsion micro lens; it can avoid amplify circuit, that directly inputting the tested current or low-frequency weak current into driving coil, to be arranged in the strong magnetic field generated by external permanent magnet; the driving coil drives the micro lens to deflect from original position by the torque generated by Lorentz force; it uses dual optical fiber collimator to test the characters that sensitive to the angle; according to the relationship between the optical signal loss and the torsion angle, via optical electric conversion and signal processing, attaining the current value. The invention can avoid amplify circuit at the input end, to attain amp level and pF level, to overcome the defects of noise disturb and excursion when amplifying the micro weak current signal. Andit can realize the optical electric separation at input and output ends synchronously, with small volume, simple structure, lower cost and better anti-vibration ability.

A magnetooptical component of spherical wave consists of magnetooptical glass body, lens and uniform magnetic field generator which are prepared by magnetooptical material. It is featured as setting magnetooptical glass body in magnetic field generated by uniform magnetic field generator, making end surface of said glass body to be planar form and sticking lens on end surface of it.

The invention discloses a fiber-isolated analog output circuit apparatus, and belongs to the technical field of a current transformer. The apparatus comprises a fiber receiving circuit, a shaping and reversing circuit, a second-order filter circuit, an attenuation compensation circuit, a voltage offset circuit and a quadruple amplification circuit, wherein the fiber receiving circuit and the shaping and reversing circuit are connected, the shaping and reversing circuit is connected with the second-order filter circuit, the second-order filter circuit is connected with the attenuation compensation circuit, the attenuation compensation circuit is connected with the voltage offset circuit, and the voltage offset circuit is connected with the quadruple amplification circuit. The apparatus provided by the invention has the following advantages: signals are transmitted through light, the problem of easy interference of signals is solved, and the signals can be transmitted over a further distance.

The invention provides a shunting turnout crushing prevention automatic control device which comprises a photosensor, a controller, a magnetic control parking device and a photovoltaic power supply which are arranged on an annunciator. When the photosensor senses that a turnout is in a locked state, a signal is output to the controller, the controller controls a strong magnet of the magnetic control parking device to move toward the direction close to steel rails, a forcedly operating locomotive is urgently vented and the automatic parking is implemented, so that the accident of crushing the turnout by the locomotive; and when the photosensor senses that the turnout is in a switching-on state, a signal is output to the controller and the controller controls the strong magnet of the magnetic control parking device to move toward the direction far away from the steel rails, so that the normal passing of the locomotive is not influenced. A locomotive automatic stop system matched with the shunting turnout crushing prevention automatic control device for use comprises a magnetic induction sensor, a locomotive monitoring device (LKj), a brake and the like which are arranged on the locomotive. The shunting turnout crushing prevention automatic control device and the locomotive automatic stop system have the advantages of effectively preventing the accident of crushing the turnout by the locomotive, which is caused by the misjudgment and the blind action of a driver and providing the reliable guarantee for the safety production.

The invention relates to a dynamic electrical stress application device for power semiconductor devices, comprising: a signal generator, an optocoupler protection module, a gate pulse drive module, a high-voltage control module and the n measured power semiconductor devices, wherein the signal generation The device, the optocoupler protection module, and the gate pulse drive module are sequentially connected to the gates of the n power semiconductor devices under test, and the high voltage control module is connected to the drains of the n power semiconductor devices under test. The source stages of the n tested power semiconductor devices are grounded. The invention also relates to a dynamic electrical stress test method for a power semiconductor device. The invention can simultaneously complete the application of dynamic electrical stress to one or more power semiconductor devices under test, realizes the photoelectric isolation between the signal generator and the high-voltage circuit through the optocoupler protection module, and facilitates the monitoring of the degradation parameters of the power semiconductor devices under test , improving the efficiency of hot-carrier reliability testing under dynamic electrical stress conditions.