CN-121994399-A - Self-adaptive digital four-hole probe and wind speed measuring device

CN121994399ACN 121994399 ACN121994399 ACN 121994399ACN-121994399-A

Abstract

According to the self-adaptive digital four-hole probe and the wind speed measuring device, the gain self-adaptive adjustment strategy realized by the microcontroller can dynamically optimize the signal amplification factor according to the real-time wind speed, so that the wind speed range of a single probe which can be accurately measured is greatly widened to 1.5-80 m/s, and the measuring resolution and the measuring range under high and low wind speeds are considered. Because the high-speed signal acquisition circuit is internally arranged in the probe, the pressure signal is directly converted into a digital signal at the source, the error caused by the characteristic change of the cable in the long-distance transmission of the analog signal is thoroughly eliminated, the system calibration is not required to be carried out again after the cable is replaced or prolonged, the deployment flexibility and the use convenience of the equipment are greatly improved, and the maintenance cost is reduced. In addition, the system structure is simplified, remote distributed measurement is supported, and applicability of the system in complex field environment is enhanced through standard Ethernet and POE power supply technology networking.

Inventors

CAI YOUFA
CONG PENGFEI
Cao tianrui
GUO HAITAO
SUN HAITONG
ZUO YUHANG

Assignees

北京思莫特科技有限公司
思莫特(天津)科技有限公司

Dates

Publication Date: 20260508
Application Date: 20260121

Claims (9)

1. An adaptive digital four-well probe, comprising: the probe is provided with four facets, and each facet is provided with a pressure measuring hole; the four pressure sensors are correspondingly connected with the four pressure measuring holes of the probe through connecting pipelines respectively and are used for converting the dynamic pressure of the air flow sensed by each pressure measuring hole into an analog electric signal; the programmable gain amplifying circuit is provided with four signal amplifying channels, the input end of each channel is connected with the output end of one pressure sensor and is used for amplifying four paths of analog pressure signals, and the gain of each channel can be independently or synchronously adjusted according to digital control instructions; the input end of the high-speed analog-to-digital conversion circuit is connected with the output end of the programmable gain amplification circuit and is used for synchronously converting the amplified four paths of analog pressure signals into digital pressure signals; The microcontroller is respectively connected with the digital control end of the programmable gain amplifying circuit and the input end and the output end of the high-speed analog-to-digital conversion circuit, and is used for executing a gain self-adaptive adjustment program, dynamically adjusting the gain of the programmable gain amplifying circuit according to the amplitude of the digital pressure signal, and packaging data containing the current gain value and the digital pressure signal; and the communication and power supply interface is connected with the microcontroller and used for receiving external power and transmitting the data packed by the microcontroller outwards.
2. The adaptive digital four-hole probe of claim 1, wherein the programmable gain amplification circuit employs a multi-channel integrated programmable gain amplifier or is comprised of a plurality of independent programmable gain amplifiers.
3. The adaptive digital quad slit probe of claim 1, wherein the communication and power interface is an ethernet interface supporting power over ethernet, the adaptive digital quad slit probe enabling data communication and power reception over a single network cable.
4. A wind speed measurement device, comprising: at least one adaptive digital four-well probe according to any one of claims 1 to 3; The switch is provided with a plurality of network ports supporting power over Ethernet, the adaptive digital four-hole probe is connected to the network ports of the switch through a network cable, and the switch supplies power to the switch and establishes network connection; The computing equipment is in communication connection with the switch and is used for receiving the data packet from the self-adaptive digital four-hole probe, processing the digital pressure signal and the gain value in the data packet based on a pre-stored pressure coefficient and a calibration data lookup table corresponding to the probe, and calculating to obtain the three-dimensional wind speed, the wind direction angle and the static pressure.
5. The wind speed measurement apparatus of claim 4, wherein a physical connection distance between the switch and the adaptive digital four-hole probe and between the switch and the computing device is not less than 100 meters.
6. The wind speed measurement device of claim 5, wherein the computing device is a personal computer, an industrial computer, or an embedded server, which has a memory unit for storing the pressure coefficient and calibration data lookup table built in or external thereto.
7. A wind speed measurement method using the wind speed measurement device according to claim 5, comprising the steps of: S1, deployment and connection, namely placing at least one self-adaptive digital four-hole probe in a wind field to be tested, connecting the self-adaptive digital four-hole probe to a network port of a switch through a network cable, connecting the computing equipment with the switch, supplying power to the self-adaptive digital four-hole probe and establishing communication; S2, signal sensing and self-adaptive amplification, namely enabling detected air flow to act on a probe of the self-adaptive digital four-hole probe to generate four paths of analog pressure signals, wherein the programmable gain amplification circuit amplifies the analog pressure signals, and the microcontroller executes the gain self-adaptive adjustment program to enable the amplitude of the amplified signals to be adapted to the measuring range of the high-speed analog-digital conversion circuit; S3, digitizing the inside of the signal, namely converting the analog pressure signal subjected to gain adjustment into a digital pressure signal by the high-speed analog-to-digital conversion circuit in the self-adaptive digital four-hole probe; S4, data transmission, namely the microcontroller transmits a data packet containing the current gain value and the digital pressure signal at the corresponding moment to the computing equipment through the communication and power supply interface and the switch; And S5, wind speed calculation, namely carrying out normalization processing on the digital pressure signal according to the received gain value in the data packet by the computing equipment, and calculating the three-dimensional wind speed, wind direction angle and static pressure by combining the pre-stored pressure coefficient and a calibration data lookup table.
8. The method of claim 7, wherein in step S2, the gain adaptive adjustment procedure is as follows, S21, initial gain setting, wherein the microcontroller controls the programmable gain amplifying circuit to adopt a preset intermediate gain value; S22, pre-sampling evaluation, namely controlling the high-speed analog-to-digital conversion circuit to perform pre-sampling to obtain a group of digital pressure signals; S23, gain decision and adjustment, namely analyzing the amplitude of the pre-sampled digital pressure signal, increasing the gain if the average amplitude is lower than a first threshold value, decreasing the gain if the average amplitude is higher than a second threshold value, and returning to the step S22; And S24, performing formal continuous acquisition and dynamic fine adjustment on the current gain, periodically evaluating amplitude trends of a plurality of groups of recently acquired digital pressure signals in the formal acquisition process, and performing small-amplitude up-adjustment or down-adjustment on the gain if the amplitude trends are continuously lower than a third threshold or higher than a fourth threshold, wherein the third threshold is higher than the first threshold and the fourth threshold is lower than the second threshold.
9. The wind speed measurement method according to claim 7, wherein in step S5, the normalization process comprises dividing the value of the digital pressure signal by the actual magnification represented by the corresponding gain value in the data packet, and restoring the value to be equivalent to the pressure signal value at the reference gain.

Description

Self-adaptive digital four-hole probe and wind speed measuring device Technical Field The invention relates to the technical field of detection, in particular to a self-adaptive digital four-hole probe and a wind speed measuring device. Background The three-dimensional dynamic wind speed measurement technology, in particular to an anemometer based on a porous probe (such as a cobra probe), is a key tool in the fields of modern hydrodynamic research, wind tunnel test, atmospheric environment monitoring, building wind engineering and the like. The device can calculate the three-dimensional instantaneous wind speed vector, wind direction angle (pitch angle and yaw angle) and static pressure of the incoming flow in real time by measuring the pressure distribution difference sensed by a plurality of pressure measuring holes which are arranged in a specific geometric way on the head of the probe and combining an aerodynamic principle with a pre-calibrated pressure coefficient and a calibrated data lookup table. The hot-wire/hot-film anemometer has the core advantages of good dynamic response performance, compact structure and high spatial resolution, is particularly suitable for a flow field environment with high turbulence intensity and complex wind direction change, and replaces the roles of the traditional hot-wire/hot-film anemometer in certain application scenes to a certain extent. A typical existing three-dimensional dynamic anemometer system is usually made up of three major parts, namely a probe, a dedicated connection cable and a central acquisition controller. Four small pressure sensors and corresponding fixed gain analog signal conditioning amplifying circuits are integrated in the probe, and four pressure measuring holes on the surface of the probe are connected with the sensors through micro pipelines. When the air flow impacts the probe, each hole generates a pressure difference signal, and the pressure difference signal is amplified by an internal circuit and then transmitted to an external acquisition controller through an analog signal cable for analog-to-digital conversion and data acquisition. The system software uses a pre-stored pressure coefficient calibrated for the specific probe and the cable length and a calibrated data lookup table to invert the acquired voltage signals into physical quantities such as wind speed. However, with the complexity of the measurement scenario and the increase of the measurement performance requirements, the above conventional structure gradually exposes two major technical bottlenecks. First, since the gain of the amplification circuit inside the probe is set by a fixed resistor, there is an inherent contradiction between the range and the resolution. When high gain is adopted to improve the measurement sensitivity at small wind speeds, the amplifier is easy to be saturated and distorted when the wind speed is larger, otherwise, low gain is adopted to expand the range, and the measurement precision and resolution of the low wind speed section are sacrificed. This makes it difficult for a single probe to maintain high accuracy measurements over a wide wind speed range (e.g., from very low wind speeds to high wind tunnel speeds), limiting the versatility of the device. Second, the system pressure coefficient and calibration data look-up table are closely related to the characteristics of the analog signal transmission path. When the length of the connecting cable between the probe and the acquisition controller is changed due to installation requirements, the resistance and the distributed capacitance of the cable change the signal transmission characteristics, and in theory, complicated system calibration needs to be performed again for the new cable length so as to ensure measurement accuracy. In practical engineering application, when measuring points are frequently replaced or distributed multi-probe arrangement is carried out, huge time cost and operation complexity are brought to recalibration work, and the measuring efficiency and the flexibility of a system are seriously affected. Therefore, how to break through the limitation of the fixed gain to the measurement range and eliminate the dependence of the signal transmission path to realize the convenience and stability of "plug and play" becomes a technical problem to be solved in the field. Disclosure of Invention The invention aims to provide a self-adaptive digital four-hole probe and a wind speed measuring device so as to solve the problems in the prior art. In order to achieve the above object, the present invention provides the following solutions: the invention provides a self-adaptive digital four-hole probe, which comprises: the probe is provided with four facets, and each facet is provided with a pressure measuring hole; the four pressure sensors are correspondingly connected with the four pressure measuring holes of the probe through connecting pipelines respectively and are used for conver