A multi-parameter cooperative control method for water level fluctuation experiment

Abstract

This invention proposes a multi-parameter collaborative control method for water level fluctuation experiments, relating to the field of automatic control technology for aquatic ecological experiments. The method includes: constructing a multi-parameter water release element table, using time nodes at each stage as scheduling benchmarks; generating initial flow control commands at stage transition times; during the water level transition period, reading the actual water level, recalculating the flow feedforward compensation, and superimposing a deviation correction term of the actual water level relative to the ideal linear trajectory to form flow control commands; calculating the moving average and moving mean square error of the water level reading sequence within a preset sliding window length; determining water level stability when both continuously and simultaneously meet their respective preset thresholds for a preset number of consecutive periods; estimating the water temperature adjustment time, and issuing the target water temperature command for the next stage to the temperature adjustment unit at the estimated time before the end of the current stage. This invention enables precise trajectory tracking of the water level transition process, reliable determination of the water level stabilization time, and time-series linkage of various experimental parameters.

Description

Technical Field

[0001] This invention relates to the field of automatic control technology for aquatic ecological experiments, and in particular to a multi-parameter collaborative control method for water level fluctuation experiments. Background Technology

[0002] Under the integrated hydro-wind-solar energy development and operation model, reservoir peak-shaving operations cause frequent and rapid intraday water level fluctuations in the reservoir area and downstream river sections, posing a significant threat to the survival, reproduction, and early resource survival of fish species such as *Schizothorax* that lay adhesive eggs. To reveal the impact mechanisms of different water level fluctuation frequencies, amplitudes, and rates on fish growth, physiology, and gonadal development, researchers need to accurately reproduce specific water level dynamic processes in a closed experimental waterway, while continuously maintaining the water temperature within a narrow ecologically required range and implementing simultaneous management of illumination and video monitoring. In existing river habitat simulation experimental waterway control systems, the water supply control software allows users to pre-compile a water release element table containing only three columns of parameters: stage duration, target flow rate, and target water level. After importation, the flow process switching can be automatically completed. However, the tailgate water level adjustment must be manually performed by the operator after the flow rate stabilizes. The water temperature regulation system and the illumination system are manually set on their respective independent operation panels, and the video monitoring system only provides continuous recording functionality. There is no linkage control relationship between the subsystems.

[0003] Chinese patent application CN113273535A discloses a river riparian habitat simulation system that facilitates the adjustment of channel slope. The system is centered around a multi-section, detachable channel supporting slope adjustment, and includes a water storage tank, a water circulation device, and a water recovery device. The channel slope can be changed by adjusting the height of the channel head. It also features a water temperature control device and a lighting device, allowing for water temperature settings at the insulation layer of the water storage tank and on the water supply pipeline, respectively. The lighting device adjusts the light intensity and period on the water surface. However, the system relies on manual settings for both water temperature regulation and lighting control on their respective independent devices, lacking automatic linkage with the water level changes in the experimental waterway. Furthermore, the system does not propose a precise trajectory control method for the water level transition process, nor does it include an automatic mechanism for determining the true stable water level, thus failing to meet the experimental control requirements of multi-parameter coordination and precise time-series linkage. Summary of the Invention

[0004] In view of this, the present invention provides a multi-parameter collaborative control method for water level fluctuation experiments. Taking the preset water level fluctuation process as a unified driving axis, the method unifies the scheduling of various subsystems such as inflow rate, tailgate opening, water temperature, illumination and video recording by expanding the water release element table, so as to realize accurate trajectory tracking of water level transition process, reliable automatic determination of water level stabilization time and accurate time-series linkage of various experimental parameters.

[0005] The technical solution of this invention is implemented as follows: This invention provides a multi-parameter coordinated control method for water level fluctuation experiments, including: Construct a multi-parameter water release element table that includes the duration of each experimental stage, steady-state target flow rate, target water level, target water temperature range, and illumination code, and pre-configure the waterway net width, using the time nodes of each stage as the scheduling benchmark. At the stage switching moment, the initial flow feedforward compensation amount is calculated based on the current actual water level, target water level, waterway net width and set water level change completion time. It is then superimposed with the steady-state target flow to generate the initial flow control command, which is synchronously issued within the same control cycle along with the target water level command and the lamp group configuration command corresponding to the illumination code. During the water level transition period, the actual water level is read cycle by cycle according to the preset sampling cycle to form a water level reading sequence. The flow feedforward compensation is recalculated based on the current real-time cross-sectional area of ​​the water passage, the remaining target water level change and the remaining set completion time. The deviation correction term of the actual water level relative to the ideal linear trajectory is superimposed. The corrected flow feedforward compensation is superimposed with the steady-state target flow to form a flow control command, which is updated and issued cycle by cycle. Calculate the moving average and moving mean square error of the water level reading sequence within a preset sliding window length. When both continuously meet their respective preset thresholds within a preset number of consecutive cycles, the water level is determined to be stable. Record this moment as the water level stabilization moment, clear the flow feedforward compensation to zero, and switch the flow control command back to the steady-state target flow. Based on the temperature difference between the median target water temperature for the next stage and the current actual water temperature, the total mass of the system water, and the rated power of the chiller and heater, the water temperature adjustment time is estimated. Before the end of the current stage, at the estimated time, the next stage target water temperature command is sent to the temperature adjustment unit in advance.

[0006] Preferably, the actual water level at the time of phase switching is used. Calculate the initial cross-sectional area of ​​the waterway with the net width W. The initial flow feedforward compensation amount is obtained based on the principle of mass conservation. : ; In the formula, The target water level for the next stage, The set time for the water level change to complete is determined by the rate setting of the current stage in the water release element table. Positive values ​​correspond to rising water levels, while negative values ​​correspond to falling water levels. Initial flow control command Depend on Received, among which This refers to the steady-state target flow rate set for this stage in the water discharge element table.

[0007] Preferably, a preset sampling period is maintained constant throughout the water level transition period. Read the actual water level cycle by cycle Let k represent the current sampling period number from the stage switching moment, then To calculate the time elapsed since the phase transition, the following intermediate quantities are calculated sequentially: Current real-time cross-sectional area of ​​water flow Remaining target water level change and remaining setting completion time ; when season To avoid division by zero.

[0008] Preferably, a trajectory deviation correction term is introduced based on the ideal linear water level trajectory; the ideal linear water level trajectory value in the k-th sampling period for: ; The deviation of the actual water level from the ideal trajectory is: ; in A positive value indicates that the actual water level is lower than the ideal trajectory, while a negative value indicates that the actual water level is ahead of the ideal trajectory. The trajectory deviation correction term is ,in This is the feedforward correction gain.

[0009] Preferably, the flow feedforward compensation amount in the kth sampling period It is obtained by superimposing the dynamic feedforward term based on the residual amount and the trajectory deviation correction term: ; And generate the flow control command for the current sampling period. The data is updated and distributed to the flow regulator periodically.

[0010] Preferably, the process for determining water level stability is as follows: Using the most recent M sampling periods as a sliding window, obtain the water level reading sequence within the sliding window and calculate the moving average. and moving mean square error : ; ; in, Let be the actual water level in the i-th sampling period, and i be the summation index within the sliding window; when and If the conditions are met simultaneously and continuously for N consecutive sampling periods, the water level is considered stable, and this moment is recorded as the water level stabilization moment. The flow feedforward compensation is cleared to zero, and the flow control command is switched back to the steady-state target flow. ;in The threshold for determining mean deviation. The threshold for determining fluctuation energy.

[0011] Preferably, the illumination combination code in the water discharge element table The value is a non-negative integer, and its corresponding lamp group configuration is predefined in the system configuration file. The lamp group configuration includes the combination of the number of 3000K and 6000K color temperature lamp groups that are turned on, as well as the switch status of each circuit. At the stage switching time, the host computer... The field sends the corresponding loop switch command to the illumination relay module.

[0012] Preferably, the median target water temperature for the next stage The target water temperature lower limit set for the next stage in the water release factor table. upper limit of target water temperature The calculation yielded: .

[0013] Preferably, the water temperature adjustment time is estimated using thermodynamics. : ; Where m is the total mass of water in the system, and c is the specific heat capacity of water. This is the current actual water temperature. P represents the absolute value of the target temperature difference, and P represents the rated cooling or heating power of the water chiller / heater. Before the end of the current phase, the host computer The system sends the target water temperature command for the next stage to the water heater in advance.

[0014] Preferably, the water release element table also includes a video trigger flag. Its value can be 0 or 1; Current stage At the moment when the water level is stable Send a recording start command to the video recorder, in order to Starting point of the behavior observation window Automatically extract time range The video clips inside, among which The preset observation duration; Automatically written in video file naming The timestamp and corresponding processing group number, and at the same time The actual water level, actual flow rate, actual water temperature, and current illumination at any given time are encoded and saved as a parameter tag file with the same name as the video file.

[0015] The present invention has the following advantages over the prior art: This invention calculates the initial flow feedforward compensation based on the current water level at the stage switching point, according to the principle of mass conservation. During the transition period, it updates the real-time cross-sectional area of ​​the water passage, the remaining water level change, and the remaining completion time periodically according to a preset sampling cycle. Simultaneously, it introduces a deviation correction term for the actual water level relative to the ideal linear trajectory, forming a dynamic feedforward correction mechanism. Compared to the static open-loop method that calculates the feedforward amount once based on the initial water level deviation, this mechanism effectively suppresses the cumulative error introduced by the continuous change of the rectangular waterway cross-sectional area with the water level and the dynamic change of the tailgate discharge, enabling the actual water level to continuously track the preset linear trajectory, thus ensuring the controllability of the water level change rate.

[0016] This invention simultaneously calculates the moving mean and moving mean square error of water level readings within a sliding window, requiring both to meet their respective thresholds for a series of consecutive sampling periods to determine water level stability. Compared to naive methods that rely solely on the amplitude of a single water level deviation, the moving mean square error condition can explicitly quantify the energy of water surface fluctuations, effectively distinguishing between situations where the water level center value is in place but the surface is still fluctuating and situations where the surface is sufficiently calm. This eliminates false "stability" misjudgments in rapid rise and fall conditions where large-flow feedforward superposition leads to significant fluctuations at the inlet.

[0017] This invention uses thermodynamic estimation to determine the time required for the water chiller / heater to adjust the system water to the target temperature. Before the end of the current experimental phase, it issues the next phase's target water temperature command, ensuring that the water temperature adjustment begins before the water level jump. Because the system water volume is large and has significant thermal inertia, advance adjustment ensures that the water temperature is already at or near the target range when the new operating condition's water level is reached, preventing the experimental subject from being continuously exposed to a temperature deviating from the target after a water level change.

[0018] This invention uses an extended water release element table as a unified scheduling benchmark. At the stage switching moment, the flow feedforward command, the tailgate target water level command, and the lamp group switching command corresponding to the illumination code are issued synchronously within the same control cycle to ensure that the water level target change and the illumination environment change are accurately aligned. The water temperature prediction command is also recorded in the parameter log with a millisecond-level timestamp, and the entire time sequence is traceable. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a flowchart of the method of the present invention; Figure 2 This is a system framework diagram of the present invention. Detailed Implementation

[0021] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0022] like Figure 1 and Figure 2 As shown, a multi-parameter collaborative control method for a water level fluctuation experiment includes: constructing a multi-parameter water release element table containing the stage duration, steady-state target flow rate, target water level, target water temperature range, and illumination code for each experimental stage, and pre-configuring the channel width, using the time nodes of each stage as the scheduling benchmark; at the stage switching time, calculating the initial flow feedforward compensation amount based on the current actual water level, target water level, channel width, and the set water level change completion time, superimposing it with the steady-state target flow rate to generate an initial flow control command, which is synchronously issued within the same control cycle along with the target water level command and the lamp group configuration command corresponding to the illumination code; during the water level transition period, reading the actual water level cycle by cycle at a preset sampling period to form a water level reading sequence, and based on the current real-time cross-sectional area of ​​the water passage, the remaining target water level change, and the remaining set... The flow feedforward compensation is recalculated upon completion, and a correction term for the deviation of the actual water level from the ideal linear trajectory is added. The corrected flow feedforward compensation is then superimposed with the steady-state target flow to form a flow control command, which is updated and issued periodically. The moving average and moving mean square error of the water level reading sequence are calculated within a preset sliding window length. When both continuously meet their respective preset thresholds for a preset number of consecutive cycles, the water level is determined to be stable, and this moment is recorded as the water level stabilization moment. The flow feedforward compensation is then cleared to zero, and the flow control command is switched back to the steady-state target flow. The water temperature adjustment time is estimated based on the temperature difference between the median target water temperature of the next stage and the current actual water temperature, the total mass of the system water, and the rated power of the chiller and heater. Before the end of the current stage, at this estimated time, the target water temperature command for the next stage is issued to the temperature adjustment unit in advance.

[0023] This embodiment uses a closed river habitat simulation waterway as the subject. The waterway has a rectangular cross-section with a net width W=0.7m, a net height of 0.45m, and a length of 17m. The supply and return water system is equipped with an 18.5kW centrifugal pump, an electromagnetic flow meter, a frequency converter, and a smart flow regulator (hereinafter referred to as "flow regulator"). The flow regulation range is... The adjustment accuracy is 1% of the range, and the stabilization adjustment time is approximately 2 minutes. A servo mechanism and a corresponding water level gauge are installed at the tailgate. The water level gauge is installed at the tailgate position of the waterway to collect the actual water level of the cross-section near the tailgate, serving as feedback for tailgate adjustment and water level stability determination. Each waterway is equipped with one chiller / heater, with a heating power of 13.5kW and a cooling power of 13.0kW, and a temperature control range of... The water temperature in the return water tank is kept constant, and the effective water volume of the return water tank is approximately... The corresponding total mass of the water body in the system The lighting system is equipped with 3000K and 6000K color temperature LED tubes, with four rows of each color temperature and nine 20W tubes in each row. Each row has an independent switch circuit, for a total of eight independent lighting circuits. The on / off state of each circuit is controlled by a light relay module. Each waterway is equipped with a high-resolution video camera, and the video signal is transmitted in real time to a hard disk recorder in the control room, supporting continuous recording and file export by time period.

[0024] The host computer establishes communication connections with the flow regulator, tailgate controller, chiller / heater, illumination relay module, and video recorder via independent serial communication channels. The serial communication baud rate is 9600bps, and each execution unit uses an independent serial channel to reduce mutual interference. The host computer uses the expanded multi-parameter water release element table as a unified scheduling benchmark, triggering control commands to the corresponding execution units at each stage's time node. The issuance time of all commands is recorded in the parameter log with a millisecond-level timestamp. The water level monitoring cycle and flow rate monitoring cycle are both set to 2 seconds by default, and the water level adjustment cycle is set to 5 seconds by default. These cycles can be adjusted according to actual needs in the system configuration interface. To ensure consistent calculation methods, the host computer performs unit normalization before calculation: the target water level expressed in millimeters (mm) in the water release element table is converted to meters (m) before calculation; the steady-state target flow rate is expressed in liters per second (L / s), and the feedforward compensation is expressed in cubic meters per second (m³ / s). 3 The values ​​are calculated as / s and then converted to liters per second using a conversion factor before being summed. In the following formulas, water level-related quantities are in meters, cross-sectional area is in square meters, flow feedforward compensation is in cubic meters per second, and flow control commands sent to the flow regulator are in liters per second.

[0025] Step 1: Construct an extended multi-parameter water release element table.

[0026] The existing water release element table, previously consisting of three columns (stage duration T (min), target flow rate Q (L / s), and target water level Z (mm), has been expanded into a configuration file containing seven columns of parameters. The newly added fields are: target water temperature lower limit. (°C), upper limit of target water temperature (°C), Lighting combination code (Non-negative integer, corresponding to predefined lamp group color temperature combinations and circuit switch states), video trigger flag (Value can be 0 or 1).

[0027] In addition to the seven columns mentioned above, the water release element table also includes a rate level field, which is used to determine the completion time of water level changes corresponding to each stage. (s), speed setting and The corresponding relationships are pre-stored in the system configuration file. When switching stages, the host computer looks up the current rate level in the water discharge element table to obtain the corresponding information. To ensure the repeatability of water level changes across different treatment groups, the expanded water release element table is saved in Excel format to maintain compatibility with existing system operating habits. After the host computer reads this table, it uses the time nodes of each stage in the table as the scheduling basis to form a stage switching scheduling sequence. At each stage switching moment, control commands are sent to the corresponding execution unit through independent serial communication channels. The time of all command issuance is recorded in the parameter log with a millisecond-level timestamp. The waterway net width W=0.7m is pre-configured as a fixed structural parameter in the host computer for use in subsequent feedforward calculations.

[0028] Step 2: Calculate the initial flow feedforward compensation at the stage switching moment, and simultaneously issue flow control commands, tailgate target water level commands, and illumination switching commands within the same control cycle.

[0029] Let the net width of the waterway be W (m). At the stage switching moment, the host computer reads the most recent sampled value of the water level gauge at the tailgate as the current actual water level. (m), the target water level for the next stage is (m, calculated from the next stage target water level field in the water release element table), the set water level change completion time is... (s, whose value is determined by the current rate setting in the water discharge element table). Calculate the initial cross-sectional area of ​​the water passage based on the geometric relationship of the rectangular cross-section. (m) 2 ): ; Where W is the net width of the waterway (m). The actual water level (m) at the moment of phase switching.

[0030] Calculate the initial flow feedforward compensation amount using the principle of mass conservation. (m) 3 / s): ; in, The initial cross-sectional area of ​​the water passage (m) 2 ), The target water level (m) for the next stage. This represents the current actual water level (m). The set water level change completion time (s) is determined by the rate setting of the current stage in the water release element table; Positive values ​​correspond to rising water levels, while negative values ​​correspond to falling water levels.

[0031] The steady-state target flow rate at this stage The initial flow control command is formed by adding (L / s) to the initial feedforward compensation. (L / s): ; in, The steady-state target flow rate (L / s) set for this stage in the water discharge element table. To be By m 3 The result is converted from / s to L / s. Since the waterway flow rate range in this embodiment is... The host computer Apply upper and lower limit constraints within this range, and record the boundary value when the limit is exceeded.

[0032] The host computer synchronously sends the following three commands within the same control cycle and records a uniform millisecond-level timestamp for this synchronization event in the parameter log: (1) Send to the flow regulator The flow regulator drives the frequency converter to adjust the water pump speed, and the electromagnetic flow meter transmits the actual flow value back in real time. The flow regulator's built-in feedback control loop maintains the actual flow at a certain level. nearby; (2) Write the target water level to the tailgate controller The tailgate controller continuously reads the feedback value of the water level gauge at the tailgate at a preset sampling period (default 2s) and drives the tailgate servo mechanism to adjust the opening to eliminate water level deviation. (3) According to the next stage of illumination combination coding Send the corresponding circuit switch command to the light relay module. See step six for details.

[0033] The three commands mentioned above are sent sequentially through their respective independent serial port channels within the same control cycle, and are marked with a unified millisecond-level timestamp as a synchronization event, ensuring that the switching times of the three subsystems of flow, water level and illumination are accurately aligned at the parameter log level.

[0034] Step 3: During the water level transition period, dynamically adjust the flow feedforward compensation amount periodically according to the preset sampling cycle, and execute it in parallel with the water level stability determination in Step 4.

[0035] After the host computer enters the water level transition period, it maintains a constant preset sampling period throughout the entire transition period. (s, default is 2s) Read the actual water level output from the water level gauge at the tailgate cycle by cycle. This forms a water level reading sequence; with k ( () represents the current sampling period number since the stage switching time. This represents the time elapsed since the phase transition. In the k-th sampling period, the current actual water level is read. (m), calculate the following quantities in sequence: Current real-time cross-sectional area of ​​water flow A (m 2 ): ; Where W is the net width of the waterway (m). The actual water level (m) for the current sampling period.

[0036] Ideal linear water level trajectory value (m), which is the water level that should be reached in the kth sampling period when the water level changes at a preset rate of uniformity. ; in, The initial actual water level (m) at the time of phase switching. The target water level (m) The set time (s) for the water level change to complete. The elapsed time (s).

[0037] Deviation of actual water level from ideal trajectory (m): ; in, A positive value indicates that the actual water level is lower than the ideal trajectory, while a negative value indicates that the actual water level is ahead of the ideal trajectory.

[0038] Remaining target water level change (m) and remaining set completion time (s): ; ; when season To avoid division by zero.

[0039] The flow feedforward compensation amount in the kth sampling period (m) 3 / s): ; Where A is the current real-time cross-sectional area of ​​the water flow (m²) 2 ), The remaining target water level change (m). Set the remaining completion time (s). For feedforward correction gain ( (used to amplify the correction magnitude of trajectory deviation to feedforward quantity). The deviation (m) of the actual water level from the ideal trajectory is given. The first term on the right side of the formula is a dynamic feedforward term based on the remaining amount, and the second term is a trajectory deviation correction term. Together, they ensure that the water level converges at the preset rate. The reasonable range of values ​​is usually within The adjustment can be made during no-load testing before the experiment; if the actual water level continues to lag behind the ideal trajectory, the adjustment should be increased appropriately. If overshoot oscillation occurs, reduce the value appropriately until the water level transition curve smoothly converges to the target value.

[0040] Will This flow control command is superimposed on the steady-state target flow rate to form the flow control command for the current sampling period. (L / s): ; in, The steady-state target flow rate is (L / s). This is for unit conversion. The host computer will... Update and send data to the flow regulator periodically; if a communication timeout or sensor data anomaly occurs, maintain... Abnormal events are recorded to avoid instruction mutations driven by abnormal data. The cycle-by-cycle feedforward update in step three and the water level stability determination in step four are executed in parallel within each sampling cycle until the water level is determined to be stable in step four, at which point the feedforward update in step three terminates.

[0041] Compared to the static open-loop method that calculates the feedforward amount once based on the initial water level deviation at the stage switching moment, the dynamic correction cycle by cycle updates the cross-sectional area of ​​the water passage and the remaining amount estimate at the latest measured water level in each sampling cycle. This eliminates the cumulative error introduced by the continuous change of the cross-sectional area of ​​the rectangular waterway with the water level and the continuous adjustment of the opening by the tailgate controller during the transition process. It is particularly effective in the 0.5-minute extreme rapid lifting and lowering condition.

[0042] Step 4: Determine water level stability based on both the moving average and the moving mean square error, and then cancel feedforward compensation.

[0043] In each sampling period, the host computer calculates the moving average of the water level readings within a sliding window consisting of the most recent M sampling periods (M=5 by default). (m) and moving mean square error (m): ; ; Where M is the sliding window length (sampling period, the default value is M=5, which corresponds to covering the water level data of the most recent 10 seconds under the default sampling period). Let be the actual water level (m) in the i-th sampling period, and let i be the summation index within the sliding window. Let be the moving average (m). Let m be the moving mean square error, used to characterize the energy of the current water surface fluctuation.

[0044] The water level is considered stable when both of the following conditions are met simultaneously for N consecutive sampling periods (default N=3, i.e., 6 consecutive seconds): ; ; in, The mean deviation threshold (m) is used to determine whether the center value of the water level has reached the vicinity of the target value. In this embodiment, it can be taken as... ; The wave energy threshold (m) is used to determine whether the water surface wave has sufficiently attenuated. In this embodiment, it can be taken as... Both can be adjusted in the system configuration file according to the actual water level fluctuation in the waterway.

[0045] Once the water level is determined to be stable, record that moment as the moment the water level stabilizes. , increase the flow feedforward compensation amount Zeroing out the flow control command switches back to the steady-state target flow. The system then enters a pure feedback steady-state control mode.

[0046] The mean deviation condition ensures the water level center value is accurate, while the fluctuation energy condition eliminates the "pseudo-stability" judgment triggered when the sensor reading just meets the amplitude threshold before the water surface fluctuation has decayed. Together, these two conditions constitute a dual convergence judgment criterion for scenarios with rapid water level changes in open channels. In scenarios where high-flow feedforward superimposed instantaneous water surface fluctuations occur at the inlet, the instantaneous reading of the water level sensor includes wave noise, the amplitude of which is on the same order of magnitude as the single deviation threshold. Relying solely on the single deviation condition may trigger a "pseudo-stability" misjudgment while the water surface is still fluctuating; therefore, the following criteria are introduced: After the condition is met, when the fluctuation has not sufficiently decayed. Continue to exceed Since the two conditions cannot be met simultaneously, the risk of misjudgment mentioned above can be effectively eliminated.

[0047] Step 5: Calculate the water temperature adjustment time and issue the target water temperature command for the next stage before the end of the current stage.

[0048] Assume the current actual water temperature is (°C), the median target water temperature for the next stage (°C) The lower limit of the target water temperature set for the next stage in the water discharge element table. (°C) and the upper limit of the target water temperature (°C) Calculated as follows: ; Let the rated cooling or heating power of the water chiller be P (kW), the total mass of water in the system be m (kg), and the specific heat capacity of water be taken as... ( This refers to the estimated time required to adjust the system water temperature from the current temperature to the target temperature. (s) is: ; Where m is the total mass of water in the system (kg), and c is the specific heat capacity of water (kg). ), The absolute value of the target temperature difference (°C) is given, and P is the rated cooling or heating power of the water chiller (kW). Unit conversion factor (after converting MJ to kJ) (Corresponding). In this embodiment, the effective water volume of the return water tank is approximately... water density is taken The total mass of the system water Heating power is taken during the heating process. Cooling operation mode takes cooling power Substitute these values ​​into the calculations. The above estimation assumes that the chiller / heater does work on the system water at its rated power, and ignores heat loss from the water channels. This is a conservative estimate.

[0049] After reading the water discharge information table, the host computer calculates the costs for each stage. If the calculated result If the remaining time is less than or equal to the current stage's remaining time, then before the current stage ends... The system continuously sends commands to the heating and chiller to set the next target water temperature; if If the duration exceeds the current stage, a temperature command is immediately issued while the water release element table is read and the experimental process is started, and the actual advance duration is recorded in the parameter log. This mechanism ensures that the water temperature regulation action starts before the water level step change, guaranteeing that the water temperature is already at or near the target range when the water level reaches the new operating condition. This eliminates the temporal superposition of the water temperature lag response and water level change, and avoids the experimental object being simultaneously subjected to the dual confusion and interference of water level stress and temperature deviation.

[0050] Step 6: Synchronize the illumination switching command according to the illumination combination code.

[0051] Light combination codes in the water release element table The value is a non-negative integer, and its corresponding lamp configuration is predefined in the system configuration file. The lamp configuration includes the combination of the number of 3000K and 6000K color temperature lamps that are turned on, as well as the switching status of each circuit. In this embodiment, the lighting system is configured with a total of 8 independent lighting circuits, including 4 circuits of 3000K color temperature lamps and 4 circuits of 6000K color temperature lamps, with each circuit corresponding to a row of 9 20W lamps. The corresponding loop switch states are predefined in the system configuration file as a mapping table between loop numbers and switch states, eliminating the need for runtime parsing of combinational logic. The host computer, at the stage switching time, determines the state based on the corresponding state of the next stage. The field lookup table retrieves the switch status of each target circuit, and the corresponding 8-circuit switch commands are sent to the illumination relay module. The illumination switching command, the flow feedforward command and the tailgate target water level command from step two are sent synchronously within the same control cycle to ensure precise alignment between changes in the illumination environment and changes in the target water level.

[0052] Step 7: Trigger video recording based on the moment when the water level stabilizes, and complete the association and archiving of the video and parameters.

[0053] The water release element table includes video trigger flags. At present stage At that time, the host computer makes a determination in step four. At the same time, a recording start command is sent to the video recorder to start recording. Starting point of the behavior observation window Automatically extract time range The video clips inside, among which The preset observation duration (in minutes, set in the system configuration file) is used. In this embodiment, the video recorder is a hard disk recorder. The host computer sends a recording trigger command to it via serial communication, and the recorder starts recording according to the command. Upon arrival, the recording stops, and the recorded video clips are automatically saved to the hard drive. The video file name is automatically written to... The timestamp and corresponding processing group number, and at the same time The actual water level, flow rate, water temperature, and current illumination at any given time are saved as parameter tag files with the same name as the video file, and these are archived one-to-one. This is based on the determination made in step four. Using the time of instruction issuance or the operator's subjective judgment as the observation starting point eliminates the systematic deviation of the observation window starting point caused by the different actual arrival times of water levels among different water level change rate processing groups; the introduction of the dual convergence criterion in step four further ensures... In a behavioral ecology sense, this corresponds to the physical moment when the water level is truly stable and the water surface is sufficiently calm, so that the behavioral data of different treatment groups have a unified and objective benchmark for comparison.

[0054] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A multi-parameter coordinated control method for water level fluctuation experiments, characterized in that, include: Construct a multi-parameter water release element table that includes the duration of each experimental stage, steady-state target flow rate, target water level, target water temperature range, and illumination code, and pre-configure the waterway net width, using the time nodes of each stage as the scheduling benchmark. At the stage switching moment, the initial flow feedforward compensation amount is calculated based on the current actual water level, target water level, waterway net width and set water level change completion time. It is then superimposed with the steady-state target flow to generate the initial flow control command, which is synchronously issued within the same control cycle along with the target water level command and the lamp group configuration command corresponding to the illumination code. During the water level transition period, the actual water level is read cycle by cycle according to the preset sampling cycle to form a water level reading sequence. The flow feedforward compensation is recalculated based on the current real-time cross-sectional area of ​​the water passage, the remaining target water level change and the remaining set completion time. The deviation correction term of the actual water level relative to the ideal linear trajectory is superimposed. The corrected flow feedforward compensation is superimposed with the steady-state target flow to form a flow control command, which is updated and issued cycle by cycle. Calculate the moving average and moving mean square error of the water level reading sequence within a preset sliding window length. When both continuously meet their respective preset thresholds within a preset number of consecutive cycles, the water level is determined to be stable. Record this moment as the water level stabilization moment, clear the flow feedforward compensation to zero, and switch the flow control command back to the steady-state target flow. Based on the temperature difference between the median target water temperature for the next stage and the current actual water temperature, the total mass of the system water, and the rated power of the chiller and heater, the water temperature adjustment time is estimated. Before the end of the current stage, at the estimated time, the next stage target water temperature command is sent to the temperature adjustment unit in advance.

2. The multi-parameter collaborative control method for water level fluctuation experiments according to claim 1, characterized in that, Based on the actual water level at the time of phase switching Calculate the initial cross-sectional area of ​​the waterway with the net width W. The initial flow feedforward compensation amount is obtained based on the principle of mass conservation. : ； In the formula, The target water level for the next stage, The set water level change completion time is determined by the rate setting of the current stage in the water release element table; Positive values ​​correspond to rising water levels, while negative values ​​correspond to falling water levels. Initial flow control command Depend on Received, among which This refers to the steady-state target flow rate set for this stage in the water discharge element table.

3. The multi-parameter collaborative control method for water level fluctuation experiments according to claim 2, characterized in that, A preset sampling period that remains constant throughout the entire water level transition period. Read the actual water level cycle by cycle Let k represent the current sampling period number from the stage switching time, then To calculate the time elapsed since the phase transition, the following intermediate quantities are calculated sequentially: Current real-time cross-sectional area of ​​water flow Remaining target water level change and remaining setting completion time ; when season To avoid division by zero.

4. The multi-parameter coordinated control method for water level fluctuation experiments according to claim 3, characterized in that, A trajectory deviation correction term is introduced based on the ideal linear water level trajectory; the ideal linear water level trajectory value in the k-th sampling period for: ； The deviation of the actual water level from the ideal trajectory is: ； in A positive value indicates that the actual water level is lower than the ideal trajectory, while a negative value indicates that the actual water level is ahead of the ideal trajectory. The trajectory deviation correction term is ,in This is the feedforward correction gain.

5. The multi-parameter coordinated control method for water level fluctuation experiments according to claim 4, characterized in that, The flow feedforward compensation amount in the kth sampling period It is obtained by superimposing the dynamic feedforward term based on the residual amount and the trajectory deviation correction term: ； And generate the flow control command for the current sampling period. The data is updated and distributed to the flow regulator periodically.

6. The multi-parameter collaborative control method for water level fluctuation experiments according to claim 1, characterized in that, The process for determining water level stability is as follows: Using the most recent M sampling periods as a sliding window, obtain the water level reading sequence within the sliding window and calculate the moving average. and moving mean square error : ； ； in, Let be the actual water level in the i-th sampling period, and i be the summation index within the sliding window; when and If the conditions are met simultaneously and continuously for N consecutive sampling periods, the water level is considered stable, and this moment is recorded as the water level stabilization moment. The flow feedforward compensation is cleared to zero, and the flow control command is switched back to the steady-state target flow. ;in The threshold for determining mean deviation. The threshold for determining fluctuation energy.

7. The multi-parameter collaborative control method for water level fluctuation experiments according to claim 1, characterized in that, Light combination codes in the water release element table The value is a non-negative integer, and its corresponding lamp group configuration is predefined in the system configuration file. The lamp group configuration includes the combination of the number of 3000K and 6000K color temperature lamp groups that are turned on, as well as the switch status of each circuit. At the stage switching time, the host computer... The field sends the corresponding loop switch command to the illumination relay module.

8. The multi-parameter collaborative control method for water level fluctuation experiments according to claim 1, characterized in that, Next stage target median water temperature The target water temperature lower limit set for the next stage in the water release factor table. upper limit of target water temperature The calculation yielded: 。 9. The multi-parameter collaborative control method for water level fluctuation experiments according to claim 8, characterized in that, The water temperature regulation time was estimated using thermodynamics. : ； Where m is the total mass of water in the system, and c is the specific heat capacity of water. This is the current actual water temperature. P represents the absolute value of the target temperature difference, and P represents the rated cooling or heating power of the water chiller / heater. Before the end of the current phase, the host computer The system sends the target water temperature command for the next stage to the water heater in advance.

10. The multi-parameter collaborative control method for a water level fluctuation experiment according to claim 1, characterized in that, The water release element table also includes video trigger flags. Its value can be 0 or 1; Current stage At the moment when the water level is stable Send a recording start command to the video recorder, in order to Starting point of the behavior observation window Automatically extract time range The video clips inside, among which The preset observation duration; Automatically written in video file naming The timestamp and corresponding processing group number, and at the same time The actual water level, actual flow rate, actual water temperature, and current illumination at any given time are encoded and saved as a parameter tag file with the same name as the video file.

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