47results about How to "Avoid the effects of electromagnetic interference" patented technology

The invention discloses a roadway surrounding rock stress monitoring device based on fiber bragg grating sensing. Grooves are symmetrically carved in a metal rod along the axial center, an FBG set is fixedly installed inside each groove, FBGs serve as sensitive elements, when roadway surrounding rock is deformed, the stress of the surrounding rock will be changed, therefore, force is generated through the metal rod, surface micro-deformation is generated, the grating distances of the FBGs attached to the metal rod are changed along with the metal rod, the center reflection wavelength of the FBGs can be caused to generate drifting, wavelength signals are demodulated into electrical signals through an FBG interrogator, and the stress situations of different sites can be obtained. The roadway surrounding rock stress monitoring device has the advantages that installation is easily achieved, and the roadway surrounding rock stress monitoring device is suitable for wide popularization; power is not required to be supplied to the working face end, and site safety is guaranteed; all-optical measurement and fiber transmission are adopted, and influences of electromagnetic interference are effectively avoided; the temperature error is compensated, and the accuracy is improved; the surrounding rock stress monitoring results can be timely and accurately provided, and guidance on site production and scientific research is facilitated.

The invention discloses a three-dimensional induced polarization method advanced forecast system carried by an earth pressure balance shield, and a detection method. The system penetrates a needle-like electrode into soil for power supply and acquisition by use of a push electrode system carried by a cutter head and overcomes the difficulty of zero detection space in a conventional earth pressure balance shield. Detection currents are enabled to be distributed forwards by use of a shielding electrode, and a guniting device on the cutter head injects a high-resistance grouting material towards soil around the cutter head and the shield, and the difficulties of electromagnetic interference and conduction of currents by taking the shield as a good conductor are overcome. By use of automatic control in a whole process, multipath parallel acquisition and a rapid inversion means, the difficulty of small detection time is overcome. The method provided by the invention realizes detection of spherical weathering bodies, soft and hard layered strata, front full-section hard rocks, pebble layers and muddy layers by use of resistivity differences among geologic bodies; and detection of water containing condition of a water-rich layer by use of excitation polarization half failure is realized.

The invention relates to a surrounding rock stress on-line monitoring system and method based on a fiber bragg grating borehole stress meter. A plurality of measurement points are arranged on a surrounding rock, the fiber bragg grating borehole stress meter is installed in a surrounding rock wall drill hole, an optical fiber connector is connected with an optical fiber, and the optical fiber is connected to a mining optical cable, is then directly connected to the ground, and is connected with a fiber bragg grating modulator; an optical signal is modulated to a digital signal by the fiber bragg grating modulator, the digital signal is transmitted to a computer, is monitored in real time and is analyzed and processed, and a surrounding rock axial stress and transverse stress analyzing and processing method is provided under the temperature compensation condition according to grating stress characteristics. The surrounding rock stress on-line monitoring system and method have the advantages that equipment is easy to install, long in service life and suitable for popularization and use; power supply is not needed underground, electrical signals and electronic devices do not exist, and therefore the field is safe; because all-optical measurement and optical fiber transmission are adopted, monitoring precision is greatly improved, and effect of electromagnetic interference can be effectively avoided under complex and poor environment; surrounding rock stress monitoring results can be provided in time and guiding of field production and scientific research work is facilitated.

A gob-side entry retaining pasty filler on-line detection method comprises the steps that before each monitored space is ready to be filled, supporting rods are fixed to a base plate of a space to be filled through ground anchors, the upper ends of the supporting rods support a top plate of the space to be filled, measuring optical fibers are arranged between the supporting rods, an optical fiber connector is introduced out of the tail portion of the last supporting rod in each set of supporting rods and is connected in a mining optical cable through optical fibers so that optical fiber monitoring signals can be transmitted to a distributed optical fiber demodulator, demodulated signals are transmitted to a computer system, and pasty filler is monitored in real time on line and is analyzed and processed after the space is filled. The gob-side entry retaining pasty filler on-line detection method has the advantages that equipment installation is easy, the method is suitable for being universally popularized, no power supply is needed under a well, a site is safe, all-optical measurement and optical fiber transmission are adopted, influences caused by electromagnetic interference are effectively avoided, a monitoring result can be provided in time, and the method is favorable for directing on-site filling mining production work.

The invention relates to an optical fiber current sensor and a manufacturing method thereof. The optical fiber current sensor comprises a first quarter wave plate, a second quarter wave plate, a sensing optical fiber and a coil frame, wherein the first quarter wave plate and the second quarter wave plate are communicated through the sensing optical fiber; the sensing optical fiber is coupled with a half-wave plate; and double wires of the sensing optical fiber double wire are wound on the coil frame in the same direction. The invention provides an optical fiber current sensor which has the advantages of high precision, small volume, light weight and no sensitivity to vibration or rotation due to no Sagnac effect and a manufacturing method thereof.

The invention belongs to mine pressure on-line monitoring systems, and discloses a working face mine pressure on-line monitoring system based on fiber grating sensing. According to the monitoring system, a plurality of measurement points are selected on a working face in a pit, one monitoring system is installed inside each measurement point, a hydraulic control valve of each monitoring system is installed in a hydraulic support and is connected with a pressure guide hole of an intrinsic safety type fiber grating pressure meter through an oil pipe, an optical signal of the intrinsic safety type fiber grating pressure meter is transmitted to a fiber grating demodulator on the ground through an optical fiber and a mining optical cable, the fiber grating demodulator is demodulated into a digital signal to be transmitted to a computer system, and the computer system carries out real-time monitoring and analysis processing. The working face mine pressure on-line monitoring system based on the fiber grating sensing has the advantages of being simple in installation, adopting full-optical measurement and optical fiber transmission, being capable of effectively avoiding influence of electromagnetic interference, greatly improving monitoring accuracy due to adoption of a temperature compensation grating for compensating a temperature error, and being capable of timely providing a working face mine pressure monitoring and predicting result so as to bring convenience to production and scientific researches of a guidance site.

The invention discloses a method for preventing the override trip of a mine power supply system, which is characterized by comprising the following steps that: 1) each protection device in a transformer substation outputs a differential signal to a mine protection transceiver, the mine protection transceiver converts an electric signal into an optical signal and sends the optical signal to a mine protection transceiver on the opposite side, and the mine protection transceiver of a transformer substation on the opposite side converts the optical signal into an electric differential signal and inputs the electric differential signal into each protection device in the transformer substation; and 2) when a fault occurs at a certain position, the protection device closest to a fault point sends a protection blocking signal to the corresponding protection devices of superior switches in turn, and a reverse blocking quick overcurrent protection device of the superior protection device cannot act after the superior protection device receives the blocking signal, and quickly removes the fault because the protection device closest to the fault point does not receive the corresponding blocking signal. By the method, the problem that an optical fiber communication signal cannot be directly connected to the protection device is solved.

A PON-CAN bus architecture and a robot system, the PON-CAN bus architecture comprising an optical fiber bus and a total information device connected to the optical fiber bus, the optical fiber bus being formed by interconnecting a plurality of asymmetric couplers; the symmetric couplers are configured to branch the next level network; the total information device is configured to perform communication interaction with the next level network through the optical fiber bus. The robotic system includes the PON-CAN bus architecture, and various terminal control systems and terminal sensing devicesof robots connected to the PON-CAN bus architecture.

A power transmission iron tower stress online monitoring system is characterized in that eight paths of vibrating wire sensor acquisition systems which are connected in parallel, an exciting circuit, a filter circuit, a shaping circuit, an STM32 processor and a wireless transmission module are connected in sequence to form the power transmission iron tower stress online monitoring system, and the whole monitoring system is powered by a solar power supply module. The power transmission iron tower stress online monitoring system is simple, low in cost, reliable and capable of accurately measuring the stress of a power transmission iron tower; in addition, the cost is low, and batch usage of the systems in a power transmission iron tower line is facilitated. A remote wireless transmission technology overcomes the influences of electromagnetic interference of the power transmission iron tower, so that the system is convenient, rapid and reliable.

The invention, which belongs to the technical field of the aviation integrated core processing, relates to an interconnection method of flexible optical fiber networks and an integrated core processorapplying the same. The integrated core processor is based on the architecture with an integrated design, a modularization idea, and unified high-speed internet interconnection. On the basis of the flexible optical fiber network interconnection method, high-speed fiber communication between all modules and between modules and other external devices is realized. The interconnection method and the integrated core processor are realized simply; the reliability and manufacturability are high; assembling becomes simple; and problems of the traditional electric signal transmission mode structure iscomplicated, the cost is high, the reliability is low, and the technical weight of the light back panel does not conform to the weight reduction requirement of the aviation product can be solved.

The invention provides a soil settlement observation and measurement system based on a Bragg grating, and relates to a soil settlement observation system. The soil settlement observation and measurement system based on the Bragg grating comprises a deformation plate, a fixed plate, a settlement rod and another deformation plate, wherein the settlement rod is arranged on the deformation plate; one end of the deformation plate is fixed at the other end of the fixed plate and is connected with the settlement rod; a deformation testing Bragg bare grating is arranged in the middle of the deformation plate and is connected with a temperature compensation Bragg bare grating through a single-mode single-core optical fiber; and the deformation testing Bragg bare grating and the temperature compensation Bragg bare grating are connected to a Bragg grating demodulator. Compared with the prior art, the measurement system is provided with an optical fiber sensor, so that influence of electromagnetic interference is avoided. Meanwhile, the soil settlement observation and measurement system has a temperature compensation function. The measurement system is stable in operation and high in measurement precision, can be regulated and changed according to measurement requirements, and can adapt to measurement of most of settlement surfaces.

The invention discloses a distributed optical fiber coal mine roof safety monitoring system and method, and belongs to the technical field of coal mine roof safety monitoring. The invention aims to provide an improvement of a distributed optical fiber coal mine roof safety monitoring system hardware structure. According to the technical scheme adopted by the invention, the system comprises a narrow linewidth laser, a distributed optical fiber multi-parameter fusion sensing system, a signal acquisition and processing module and a GFPR optical cable; light waves generated by the narrow linewidth laser enter the distributed optical fiber multi-parameter fusion sensing system; a Brillouin scattering light signal and a Rayleigh scattering light signal generated by the GFPR optical cable enter the distributed optical fiber multi-parameter fusion sensing system; the distributed optical fiber multi-parameter fusion sensing system outputs the Brillouin scattering light signal and the Rayleigh scattering light signal to the signal acquisition and processing module; and the signal acquisition and processing module acquires Brillouin frequency shift and Rayleigh scattering light phase and intensity at the same time through demodulation to obtain strain, temperature and micro-seismic information along the GFPR optical cable. The system and method are applied to coal mines.

The invention belongs to the field of control, in particular to a current harmonic suppression control algorithm of a four-quadrant converter, and particularly relates to a current low-order harmonicsuppression method for a four-quadrant converter of an electric locomotive. The method is a harmonic suppression method fused in a four-quadrant control algorithm, solves the problems of influence ofcurrent low-order harmonics of the four-quadrant converter on the control of the converter and pollution to the electric energy quality of a power grid, and solves the problem of influence caused by filtering the low-order harmonics by adopting a software filter method. According to the method, a harmonic extraction and suppression function is added to the four-quadrant converter control algorithm, no extra hardware control circuit or device is added, so the method has high adaptability and flexibility, the purpose of harmonic suppression can be achieved, and meanwhile the design cost is reduced.

The invention discloses a filling body transverse deformation online monitoring system based on fiber bragg grating sensing, and relates to the technical field of mine filling body monitoring. The device comprises a bidirectional displacement measuring device based on fiber bragg grating sensing, a fixed disc, a coupler, an optical fiber, a mining optical cable, a fiber bragg grating demodulator and a computer system, the bidirectional displacement measuring device based on fiber bragg grating sensing comprises a measuring main body, an extension line, a steel pipe and two fiber bragg gratingdisplacement sensors, wherein the measuring main body comprises a shell and an upper cover matched with the shell; the shell is of a hollow cuboid structure, the left side and the right side of the shell are each provided with an outlet, the movable pull rods of the two fiber bragg grating displacement sensors penetrate through the outlets in the left side and the right side respectively and facethe outlets in the left side and the right side of the shell, and the axes of the movable pull rods are overlapped with the axes of the corresponding outlets. Real-time and on-line remote monitoring of the left side, the right side and the total transverse deformation of the filling body can be achieved.

The invention discloses a wireless unmanned aerial vehicle charging system with an optical communication function. The system comprises an unmanned aerial vehicle charging airport end and an unmanned aerial vehicle end, wherein the unmanned aerial vehicle charging airport end comprises an airport optical communication transmitting module, a wireless charging transmitting device and an airport optical communication receiving module; the unmanned aerial vehicle end comprises an unmanned aerial vehicle optical communication receiving module, a wireless charging receiving device and an unmanned aerial vehicle optical communication transmitting module; the airport optical communication transmitting module of the unmanned aerial vehicle airport end sends an optical signal to the unmanned aerial vehicle optical communication receiving module of the unmanned aerial vehicle end, and the unmanned aerial vehicle optical communication transmitting module of the unmanned aerial vehicle end sends an optical signal to the airport optical communication receiving device of the unmanned aerial vehicle charging airport end; and a wireless charging transmitting device of the unmanned aerial vehicle charging airport end sends charging energy to the unmanned aerial vehicle, and the unmanned aerial vehicle end receives the charging energy based on a wireless charging receiving device. According to embodiments of the invention, signal transmission is realized through a simple structure, and the influence of electromagnetic interference on the optical signal in a transmission process is avoided.