A method for measuring reservoir capacity without tide gauge based on dynamic precise point positioning

Abstract

This invention discloses a method for measuring the reservoir capacity without tide gauge based on dynamic precise single-point positioning, which includes the following steps: S1: Receiving signals from satellites in real time via a GNSS receiver; S2: Downloading precise ephemeris and precise clock difference products; S3: Calculating the reservoir bottom elevation difference for each epoch: H ij =z-H 泥面 S5: Reservoir capacity: V 总 =ΣH ij *a*b. Advantages: It can complete the measurement of reservoir capacity under conditions of poor or no network; the precise single-point positioning technology has changed the previous situation where only the dual-difference phase positioning mode could achieve high positioning accuracy; the use of precise single-point positioning technology can save users the cost of purchasing receivers, and users can achieve high-precision dynamic positioning with a single receiver, which can also improve the efficiency of GPS operations.

Description

Technical field:

[0001] The invention relates to the technical field of storage capacity measurement of non-tidal gauge reservoirs, and in particular to a storage capacity measurement method of non-tidal gauge reservoirs based on dynamic precise single-point positioning. Background technology:

[0002] Conventional water depth measurement requires tide gauge so that water level correction can be added to the measured water depth value. This can obtain satisfactory results when the measurement area is small and the sea conditions are ideal. However, when the measurement area is large and factors such as tidal range and wind and waves are complex, not only is the workload of tide gauge large, but the accuracy of water level correction is often not ideal, which directly affects the quality of water depth results. Using RTK for water depth measurement can achieve a tide-free mode, that is, there is no need to conduct a special tide gauge, and the water level correction value is directly measured during the measurement process. At the same time, RTK can also be used to determine the attitude of the ship during the measurement, that is, the ship attitude correction can be performed and the impact of wind and waves on water depth measurement can be reduced, thereby improving the accuracy of water depth measurement results. When measuring in areas with large wind, waves and tidal ranges, the operational advantages of RTK are particularly obvious. However, RTK technology requires network or base station support. In mountainous or remote areas without network coverage or poor signal quality, high-precision surveying and mapping cannot be completed, which reduces the efficiency of field acquisition and increases costs. Summary of the invention:

[0003] The object of the present invention is to provide a method for measuring reservoir capacity without tide gauge based on dynamic precise single point positioning.

[0004] The present invention is implemented by the following technical scheme: a method for measuring the storage capacity of a reservoir without tide gauge based on dynamic precise single point positioning, which comprises the following steps:

[0005] S1: Receive signals from satellites in real time through a GNSS receiver, measure the time difference between the received signal and the satellite, and then calculate the position data and speed data of the receiver, and store the position data and speed data;

[0006] S2: Download precise ephemeris and precise clock products, and use WUM products to correct the downloaded precise ephemeris and precise clock products respectively;

[0007] S3: The elevation value h of the antenna center of the GNSS receiver at a certain moment is calculated through dynamic single-point positioning, and the height from the antenna to the water surface is h1; the underwater coordinates are obtained indirectly using a depth sounder, and the depth of the depth sounder transducer from the water surface is h2. The time interval t between the depth sounder transducer transmitting and receiving the beam echo and the average propagation speed v of the sound wave in the water body can be used to calculate the measured water depth h3 = 1 / 2tv, then the actual water depth D = h2 + h3, and the mud surface elevation of the measuring point can be calculated as: H 泥面 =h-h1-D;

[0008] S4: The coordinates (x, y, z) collected at each epoch are solved using the dynamic precise point positioning method. Finally, the point cloud data is established based on the results of the dynamic precise point positioning and the coordinate z of the echo sounder corresponding to the epoch. The elevation difference of the reservoir bottom corresponding to each epoch is calculated using the grid method:

[0009] H ij =z-h1-H 泥面

[0010] Among them, H ij Represents the height difference of the grid in row i and column j;

[0011] S5: Reservoir capacity:

[0012] V 总 =∑H ij *a*b

[0013] Among them, V 总 Represents the overall capacity of the reservoir; a and b are the length and width of the grid, respectively.

[0014] The advantages of the present invention are as follows: the measurement of reservoir capacity can be completed under the condition of poor network or no network; the precise single-point positioning technology has changed the previous situation that only the double-difference phase positioning mode can be used to achieve higher positioning accuracy; the use of precise single-point positioning technology can save users the cost of purchasing receivers, and users can achieve high-precision dynamic positioning using a single receiver, and can also improve GPS operation efficiency. Description of the drawings:

[0015] Figure 1 is a flow chart of the method of this embodiment.

[0016] Figure 2 This is the elevation space relationship diagram of this embodiment. Specific implementation method:

[0017] like Figure 1 and Figure 2 As shown, a method for measuring reservoir capacity without tide gauge based on dynamic precise single point positioning includes the following steps:

[0018] S1: Receive signals from satellites in real time through a GNSS receiver, measure the time difference between the received signal and the satellite, and then calculate the position data and speed data of the receiver, and store the position data and speed data;

[0019] S2: Download precise ephemeris and precise clock products, and use WUM products to correct the downloaded precise ephemeris and precise clock products respectively;

[0020] S3: The elevation value h of the antenna center of the GNSS receiver at a certain moment is calculated through dynamic single-point positioning, and the height from the antenna to the water surface is h1; the underwater coordinates are obtained indirectly using a depth sounder, and the depth of the depth sounder transducer from the water surface is h2. The time interval t between the depth sounder transducer transmitting and receiving the beam echo and the average propagation speed v of the sound wave in the water body can be used to calculate the measured water depth h3 = 1 / 2tv, then the actual water depth D = h2 + h3, and the mud surface elevation of the measuring point can be calculated as: H 泥面 =h-h1-D;

[0021] S4: The coordinates (x, y, z) collected at each epoch are solved using the dynamic precise point positioning method. Finally, the point cloud data is established based on the results of the dynamic precise point positioning and the coordinate z of the echo sounder corresponding to the epoch. The elevation difference of the reservoir bottom corresponding to each epoch is calculated using the grid method:

[0022] H ij =z-h1-H 泥面

[0023] Among them, H ij Represents the height difference of the grid in row i and column j;

[0024] S5: Reservoir capacity:

[0025] V 总 =∑H ij *a*b

[0026] Among them, V 总 Represents the overall capacity of the reservoir; a and b are the length and width of the grid, respectively.

[0027] The dynamic precise point positioning technology in the present invention uses the IGS precise orbit and precise satellite clock error products to perform non-differential positioning processing on the phase and pseudo-range observations collected by a single dual-frequency receiver. Generally, the ionosphere-free combined observation equation is used, and its mathematical model is as follows:

[0028]

[0029] Among them, P i is loaded on the carrier L i Code observation value on φ i is the carrier phase observation value; ρ is the station-satellite distance; c is the speed of light; dt is the receiver clock error; d trop is the tropospheric delay; f i For L i The frequency of N i For L i The integer ambiguity on ; ε(ΦIF) is the measurement noise.

[0030] After linearizing formula (1) and (2), we can obtain

[0031] L1=L i -φ model1 =A1X1+B1dt1+C1N3+d trop1 +φ others1 +ε1 (3)

[0032] Among them, X1 includes position parameters (x, y, z), speed parameters and acceleration parameters dt1 is the receiver clock error parameter t1 and clock rate parameter dt on the mobile station i ; N3 is the ionospheric-free combined ambiguity parameter; d trop1 is the tropospheric delay parameter; L1 is the combined observation value; φ model1 is the sum of errors that can be corrected using models, including relativity, earth rotation, ocean tide, solid tide, antenna phase center, etc., that is, modeling corrections are made to some observation errors; others1 It is the sum of other errors that cannot be corrected by accurate models, such as atmospheric error, orbit error, clock error, multipath, etc.; ε1 is the residual of the observation value.

[0033] Using the above observation model (Formula 3), Kalman filtering or sequential adjustment can be used to perform non-differenced precise point positioning calculations. When solving, when there is no cycle slip or the cycle slip is repaired, the integer unknown is treated as a constant. When a cycle slip occurs, the integer unknown is treated as a new constant parameter. Since the receiver clock is relatively unstable and there is obvious random jitter, the receiver clock error parameter is treated as white noise. The satellite elevation angle model is improved by combining the precise ephemeris and precise clock error correction of different satellites. The static precise point positioning experiment is conducted on the observation data of different stations for a single day to obtain the positioning performance of the improved satellite elevation angle model and establish a regional satellite elevation angle model. The tropospheric influence changes relatively slowly, and the Saastamonen or other models are used for correction first, and then the random walk method is used to estimate its residual influence.

[0034] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for measuring reservoir capacity without tide gauge based on dynamic precise point positioning, characterized in that: It includes the following steps: S1: Receive signals from satellites in real time through a GNSS receiver, measure the time difference between the received signal and the satellite, and then calculate the position data and speed data of the receiver, and store the position data and speed data; S2: Download precise ephemeris and precise clock products, and use WUM products to correct the downloaded precise ephemeris and precise clock products respectively; S3: The elevation value h of the antenna center of the GNSS receiver at a certain moment is calculated through dynamic single-point positioning, and the height from the antenna to the water surface is h1; the underwater coordinates are obtained indirectly using a depth sounder, and the depth of the depth sounder transducer from the water surface is h2. The time interval t between the depth sounder transducer transmitting and receiving the beam echo and the average propagation speed v of the sound wave in the water body can be used to calculate the measured water depth h3 = 1 / 2tv, then the actual water depth D = h2 + h3, and the mud surface elevation of the measuring point can be calculated as: H 泥面 =h-h1-D; S4: The coordinates (x, y, z) collected at each epoch are solved using the dynamic precise point positioning method. Finally, the point cloud data is established based on the results of the dynamic precise point positioning and the coordinate z of the echo sounder corresponding to the epoch. The elevation difference of the reservoir bottom corresponding to each epoch is calculated using the grid method: H ij =z-h1-H 泥面 Among them, H ij Represents the height difference of the grid in row i and column j; S5: Reservoir capacity: V 总 =∑H ij *a*b Among them, V 总 Represents the overall capacity of the reservoir; a and b are the length and width of the grid, respectively.

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