6results about How to "Realize simple structure" patented technology

The invention discloses an infrared bipolar linearly-polarized photoelectric detector and a preparation method thereof, and the infrared bipolar linearly-polarized photoelectric detector is characterized in that a bipolar material graphene is used as a channel material, a two-dimensional N-type semiconductor material molybdenum disulfide MoS2 and an anisotropic narrow-band-gap two-dimensional material black phosphorus BP are stacked on the bipolar material graphene in sequence, and the two-dimensional N-type semiconductor material molybdenum disulfide MoS2 and the anisotropic narrow-band-gap two-dimensional material black phosphorus BP are stacked on the channel material; the polarity of the graphene is regulated and controlled by the bottom gate, the infrared bipolar linearly polarized photoelectric detector with the bipolar linear polarization detection effect that the light current symbol reversibly turns over along with the polarization direction in the infrared band is achieved, and the infrared bipolar linearly polarized photoelectric detector has the advantages of being simple in structure, easy to regulate and control, capable of remarkably improving polarization recognition precision and the signal-to-noise ratio and the like. The programmable and multifunctional integration potential is also realized.

The present invention belongs to a spatial optical communication FEC decoding method. In order to solve the technical problem that the method for performing service data error correction by FEC encoding and decoding in the current spatial laser communication cannot perform normal error correction when the signal-to-noise ratio of the original signal is too low, a spatial optical communication FEC decoding method and system based on random resonance are provided. Aiming at the problem that the signal-to-noise ratio of the optical signal is poor after the spatial optical signal is transmitted over a long distance, the normalized scale transformation bistable random resonance is adopted to process the baseband electrical signal waveform after digital-to-analog conversion sampling, which can effectively improve the signal-to-noise ratio before entering the decoding. The decoding method is not limited by the channel coding type, is applicable to different types of decoding processing, and is performed in the digital domain, is easy to integrate, and is particularly suitable for small platform applications with limited volume and weight.

The invention discloses a power distribution droop control method and a power distribution droop control system for multiple parallel static var generators, which are characterized in that under the control method of an original active power filter, each harmonic component of power grid voltage is added into an instruction value of a current control inner loop of the active power filter through a band-pass filter, so that the phenomenon of harmonic compensation resonance is inhibited. And aiming at a nonlinear load, the harmonic compensation effect can be better realized, and the overall stability of the system is improved. Meanwhile, a simulation model of the active power filter applied to compensation of nonlinear load harmonic waves is established, simulation verification is performed on the proposed control method and related algorithms, and correctness, practicability and reliability of the method are proved. The system is good in stability, low in implementation cost, simple and efficient in implementation structure, wide in applicability, capable of adapting to various complex power grid environments and relatively practical in engineering application value.

This invention discloses an improved sliding mode observer for permanent magnet synchronous motor control and a system relating to the field of motor control technology. Addressing the problems of severe chattering and low estimation accuracy in traditional sliding mode observers, the method includes: acquiring the motor voltage and current and transforming them to a stationary coordinate system; using an adaptive sliding mode observer integrating a fuzzy adaptive adjustment unit and a smoothing switching unit for state observation, outputting a smoothed back EMF estimation signal, wherein the fuzzy adjustment unit dynamically adjusts the sliding mode gain based on the current error, and the smoothing switching unit generates a continuous control signal to suppress chattering; inputting the smoothed back EMF signal into a phase-locked loop (PLL) unit to synchronously extract rotor position angle and speed estimates for closed-loop control. The system includes signal detection, an adaptive sliding mode observer, a PLL, and a closed-loop control module. This invention improves the accuracy of speed and position observation and system stability by synergistically suppressing chattering through fuzzy adaptive and smoothing switching, and by avoiding phase delay through a PLL.

The present invention discloses a low sidelobe broadband low cross-polarization planar dipole antenna array, comprising a multilayer dielectric substrate; a first metal surface; a second metal surface; a feed network; a dipole antenna array; each dipole antenna unit comprises a top dipole arm, a middle dipole arm, and a bottom dipole arm; the first metal surface is connected to one end of the top dipole arm; the second metal surface is connected to one end of the bottom dipole arm; the feed network comprises a signal conducting strip and a metallized through hole; the signal conducting strip at the output end of the feed network is directly connected to the signal input end of each dipole antenna unit; the antenna array etches a pair of slits at appropriate positions, so that the dipole works in a half-wavelength mode and a 1.5 times wavelength mode at the same time, greatly improving the impedance bandwidth of the dipole antenna. The antenna array adopts a SICL structure for feeding, which can effectively suppress the cross polarization of the dipole antenna, and the SICL structure works in a quasi-TEM mode without a cutoff frequency.

The 2AMT speed change assembly is characterized in that a main shaft is sleeved with a spline housing, a first-gear transmission gear and a second-gear transmission gear which are located on the two sides of the spline housing are both movably arranged on the main shaft in a sleeving mode, the first-gear transmission gear and the second-gear transmission gear are fixedly sleeved with a first-gear sleeve and a second-gear sleeve respectively, and a sliding sleeve is arranged on the spline housing in a sleeving mode; the outer spline of the spline sleeve is in key connection with the inner spline of the sliding sleeve, and when the sliding sleeve axially slides on the spline sleeve, the inner spline of the sliding sleeve can be in key connection with the first gear connecting key of the first gear sleeve or the second gear connecting key of the second gear sleeve. The 2AMT speed change assembly is simple in structure and convenient to switch and has a gear locking function.