Single lamp controller dimming accuracy correction method and system for intelligent lighting system

Abstract

The application provides a single lamp controller dimming precision correction method and system for a smart lighting system, relates to the technical field of smart lighting, and comprises the following steps: acquiring a dimming power error tolerance threshold and a reference power of a load lamp when a controller is powered on or reset, and re-determining the reference power by power sampling under a preset dimming level when the reference is invalid; for a target dimming level, calculating a theoretical reference power based on the reference power; collecting load power in a stable sampling window and calculating a power error; adjusting dimming output according to the comparison result of the error and the tolerance threshold until the error meets the threshold requirement; and updating the reference power and the error threshold online according to the instruction of an upper system during operation. The application can realize dynamic maintenance of the reference power and stable convergence of error correction, and improve the long-term precision and operation stability of single lamp control of smart lighting.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of intelligent lighting, in particular to a single lamp controller dimming precision correction method and system for an intelligent lighting system. BACKGROUND

[0002] An intelligent lighting system usually implements independent dimming of each lamp through a single lamp controller to achieve on-demand lighting and energy-saving control. Existing single lamp controllers generally generate a control signal according to a dimming level issued by an upper system, and calculate the load power according to a preset ratio or a lookup table relationship internally. However, factors such as lamp driver characteristics, line voltage drop, environmental temperature, and device aging can cause a deviation between the actual power and the theoretical target power under the same dimming level. To compensate for this deviation, existing methods generally record the power data once at the factory or installation stage as a reference, and correct the control output by periodic sampling during operation. However, this type of scheme generally assumes that the reference power remains valid in the long term, without considering the reference invalidation problem caused by lamp replacement, aging, or environmental changes; when the reference parameter drifts, the target power calculation is inaccurate, and the dimming control precision gradually decreases with the running time.

[0003] On the other hand, the single lamp controller is easily affected by power grid fluctuations, dimming switch transients, and driver internal pulsations when actually collecting the load power. If sampling is performed during unstable periods or the original power difference is directly used for adjustment, transient errors are easily introduced, causing the correction process to overshoot, oscillate, or not converge for a long time. Some control methods suppress fluctuations by delaying sampling or fixed-step adjustment, but lack clear definitions of stable sampling periods and power error tolerance, making it difficult to maintain the reliability and consistency of correction under varying conditions. SUMMARY

[0004] In view of the deficiencies of the prior art, the present application provides a single lamp controller dimming precision correction method and system for an intelligent lighting system.

[0005] In a first aspect, the present application provides a single lamp controller dimming precision correction method for an intelligent lighting system, comprising:

[0006] When the single lamp controller is powered on or reset, a dimming power error tolerance threshold and a reference power of a load lamp are obtained; in response to the reference power being invalid, dimming is performed at a preset dimming level, the current load power is collected, and the reference power is determined according to the current load power and the preset dimming level;

[0007] For a target dimming level, a theoretical reference power under the target dimming level is calculated based on the reference power;

[0008] collecting a current load power in a stable sampling window determined to be stable, and calculating a power error between the current load power and the theoretical reference power;

[0009] in response to an absolute value of the power error being greater than the dimming power error tolerance threshold, adjusting a dimming output according to a sign of the power error, and repeating the sampling and error calculation after each adjustment until the absolute value of the power error is less than or equal to the dimming power error tolerance threshold;

[0010] in response to receiving an update instruction for the dimming power error tolerance threshold or the reference power, updating the dimming power error tolerance threshold and / or the reference power.

[0011] Optionally, the determination condition of the stable sampling window is based on at least one of the following:

[0012] a variation of the dimming control quantity in the sampling window is less than or equal to a preset amplitude threshold;

[0013] a duration in which the dimming control quantity remains unchanged in the sampling window is not less than a preset minimum duration.

[0014] Optionally, the updating comprises:

[0015] writing the updated dimming power error tolerance threshold and / or the reference power into a non-volatile memory.

[0016] Optionally, the determining the reference power comprises:

[0017] determining a calibration sampling window according to the determination condition of the stable sampling window at the preset dimming level, and collecting current load power samples in multiple periods in the calibration sampling window;

[0018] performing statistical estimation on the samples to obtain a calibration power estimation value;

[0019] converting the calibration power estimation value into the reference power based on a conversion relationship between the preset dimming level and power.

[0020] Optionally, the converting the calibration power estimation value into the reference power comprises:

[0021] Within a neighboring dimming level range centered on the preset dimming level, a trial disturbance with an amplitude less than or equal to the first microstep is injected into the dimming control quantity. The amplitude of the trial disturbance satisfies the constraint of the dimming power error tolerance threshold, and the duration of the trial disturbance satisfies the constraint of the preset flicker suppression threshold. Load power response data corresponding to the trial disturbance is collected within the calibration sampling window. The load power response data includes at least the current load power before the disturbance and the current load power after the disturbance.

[0022] Based on the relationship between the amplitude of the trial disturbance and the load power response data, the local slope of the power relative to the dimming control amount at the preset dimming level is calculated, and the local linearization conversion is performed on the calibrated power estimate accordingly to obtain the reference power.

[0023] Optionally, the calculation of the theoretical reference power at the target dimming level includes:

[0024] According to the preset mapping relationship, the nominal theoretical reference power is calculated based on the reference power and the target dimming level;

[0025] Within the neighborhood of the target dimming level, voltage and current data of a single lamp port are collected, and the active component projection of the grid fundamental wave is performed on the voltage and current data to calculate the active equivalent admittance of the single lamp port.

[0026] Based on the active equivalent admittance and the predicted load current determined by the nominal theoretical reference power, the line transmission loss correction is calculated.

[0027] The line transmission loss correction is applied to the nominal theoretical reference power to obtain the compensated theoretical reference power.

[0028] A monotonic projection constraint is applied to the compensated theoretical reference power so that it remains monotonically constant with the target dimming level and falls within a preset compensation range.

[0029] Optionally, the calculation of the line transmission loss correction includes:

[0030] The line loss dominant component is formed by the square of the equivalent resistance of the line and the current estimate used to calculate the line transmission loss correction, and the proportion of the line loss dominant component to the line transmission loss correction is not less than a preset lower limit within a preset current operating range.

[0031] Optionally, the calculation of the line transmission loss correction based on the active power equivalent admittance and the predicted load current determined by the nominal theoretical reference power includes:

[0032] Based on the nominal theoretical reference power and the active equivalent admittance, and according to the fact that the active power at the lamp terminal is directly proportional to the square of the fundamental voltage at the lamp terminal, the algebraic solution of the fundamental voltage at the lamp terminal is determined.

[0033] Based on the active equivalent admittance and the lamp terminal fundamental voltage, determine the lamp terminal fundamental current;

[0034] The dominant component of line transmission loss is obtained by combining the equivalent resistance of the line with the square of the fundamental current at the lamp end.

[0035] Substitute the dominant component into the power conservation relationship so that the power at the controller end is equal to the sum of the power at the lamp end and the line transmission loss. Then, perform an algebraic solution under this relationship to obtain the line transmission loss correction amount.

[0036] A non-negative constraint and a preset upper and lower limit constraint are applied to the line transmission loss correction amount, and the line transmission loss correction amount is made monotonically constant with the target dimming level.

[0037] Optionally, calculating the power error between the current load power and the theoretical reference power includes:

[0038] The instantaneous active power sample of a single lamp port is obtained within a coherent accumulation window whose duration is an integer multiple of both the grid cycle and the dimming pulse cycle, and whose start and end points are aligned with the grid zero-crossing point.

[0039] Based on the first-order slope threshold determination of the instantaneous active power, the neighborhood of each dimming upper and lower edge is adaptively expanded to form a boundary descrambling zone, and samples within the boundary descrambling zone are removed.

[0040] The average value of the samples within the window after the removal is used to obtain the estimated value of the current load active power, and the difference between this value and the theoretical reference power is used to obtain the power error.

[0041] Calculate the beat frequency residual index, which is used to characterize the energy proportion of the instantaneous active power sample in the beat frequency band. When the beat frequency residual index is less than or equal to a preset residual threshold, output the power error of the current cycle; otherwise, maintain the power error of the previous effective cycle.

[0042] Secondly, this application provides a dimming accuracy correction system for a single-lamp controller in a smart lighting system, comprising:

[0043] The acquisition module is used to acquire the dimming power error tolerance threshold and the reference power of the load lamp when the single lamp controller is powered on or reset; in response to the invalidity of the reference power, dimming is performed at the preset dimming level, the current load power is acquired, and the reference power is determined based on the current load power and the preset dimming level;

[0044] The first processing module is used to calculate the theoretical reference power at the target dimming level based on the reference power.

[0045] The second processing module is used to acquire the current load power within a sampling window that is determined to be stable, and to calculate the power error between the current load power and the theoretical reference power.

[0046] The correction module, in response to the absolute value of the power error being greater than the dimming power error tolerance threshold, adjusts the dimming output according to the sign of the power error; after each adjustment, it repeats the sampling and error calculation until the absolute value of the power error is less than or equal to the dimming power error tolerance threshold.

[0047] The update module, in response to receiving an update instruction for the dimming power error tolerance threshold or the reference power, updates the dimming power error tolerance threshold and / or the reference power.

[0048] Compared with existing technologies, this application achieves dynamic updates of the reference power by determining the validity of the reference power during the power-on or reset phase and automatically performing power sampling to re-determine the reference value when the reference is invalid, thus ensuring the consistency between the target power calculation and the actual load performance. By collecting power data and calculating the power error within a stable sampling window, it avoids measurement deviations caused by transient factors such as dimming switching and line fluctuations, improving the reliability of error calculation. Based on the absolute value of the power error and the error tolerance threshold, a closed-loop adjustment mechanism with a clear convergence boundary is constructed, enabling the dimming output to converge quickly and stably within a limited range, preventing system oscillation and overcorrection. Furthermore, by setting an online parameter update channel, the controller can automatically adapt after equipment aging, lamp replacement, or adjustments to the upper-level system strategy, maintaining dimming accuracy and long-term operational stability.

[0049] In summary, this invention achieves an organic combination of benchmark dynamic maintenance, accurate error measurement, and closed-loop stable correction in smart lighting single-lamp control scenarios, significantly improving the accuracy, response speed, and adaptive capability of dimming control. Attached Figure Description

[0050] Figure 1 A flowchart illustrating a method for correcting the dimming accuracy of a single-lamp controller in a smart lighting system, provided in an embodiment of this application.

[0051] Figure 2 A flowchart illustrating a method for determining the reference power provided in an embodiment of this application;

[0052] Figure 3 A flowchart illustrating a method for converting a calibration power estimate into a reference power, provided in an embodiment of this application;

[0053] Figure 4 This application provides a schematic diagram of a single-lamp controller dimming accuracy correction system for a smart lighting system. Detailed Implementation

[0054] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments.

[0055] See Figure 1 The flowchart shown is a method for correcting the dimming accuracy of a single lamp controller in a smart lighting system according to an embodiment of this application, including steps S101 to S105, wherein:

[0056] S101: When the single lamp controller is powered on or reset, obtain the dimming power error tolerance threshold and the reference power of the load lamp; in response to the invalidity of the reference power, perform dimming at the preset dimming level, collect the current load power, and determine the reference power based on the current load power and the preset dimming level;

[0057] S102: For the target dimming level, calculate the theoretical reference power at the target dimming level based on the reference power;

[0058] S103: Collect the current load power within the sampling window that is determined to be stable, and calculate the power error between the current load power and the theoretical reference power;

[0059] S104: In response to the absolute value of the power error being greater than the dimming power error tolerance threshold, adjust the dimming output according to the sign of the power error; repeat sampling and error calculation after each adjustment until the absolute value of the power error is less than or equal to the dimming power error tolerance threshold.

[0060] S105: In response to receiving an update instruction for the dimming power error tolerance threshold or the reference power, update the dimming power error tolerance threshold and / or the reference power.

[0061] Regarding S101 above: In one embodiment, the single-lamp controller includes a metering module, a storage unit, a host communication unit, and a dimming execution unit. After power-on or reset, the controller first obtains the dimming power error tolerance threshold and the reference power from the host communication unit and / or the storage unit; if a valid reference power is not obtained, the reference power is determined to be invalid. The determination of invalid reference power includes at least one of the following situations: not written or read failed; verification failed or the stored value exceeds the allowable range; the preset validity period has expired since the last calibration; a lamp replacement event is detected or the operating environment is abnormal. A lamp replacement event can be determined by a host maintenance command, a change in lamp identification information, or a sudden change in steady-state power at the same dimming level; an environmental abnormality can be triggered by a temperature or bus voltage over-limit flag.

[0062] For example, the dimming power error tolerance threshold is issued by the host system and cached in the storage unit; when the host system fails to issue the threshold or communication is abnormal, the controller reads the most recent valid value, and if it is still unavailable, the default configuration is used.

[0063] In some implementations, the tolerance threshold is calculated based on the correspondence between the allowable deviation of on-site illuminance and the power-illuminance sensitivity. In other implementations, the tolerance threshold is determined based on the power fluctuation range of historical operating data, for example, taking the high percentile of historical fluctuations as the tolerance boundary. A tiered tolerance strategy can be adopted for different road or scene levels. The tolerance threshold has an expiration date and can be updated online during seasonal changes, maintenance adjustments, or changes in the higher-level strategy. When the threshold expires or verification fails, the controller rolls back according to the priority order of "higher-level - cache - default". In subsequent closed-loop operations, the controller compares the absolute value of the power error with this threshold as the criterion for entering and exiting correction.

[0064] Furthermore, in response to an invalid reference power, the controller drives the load at a preset dimming level. To avoid brightness fluctuations perceptible to the naked eye, the calibration process is constrained by a flicker suppression threshold, and sampling is triggered after a delay if necessary after switching. The controller determines to start acquisition based on a stable sampling window, which must satisfy at least one of the following conditions: the change in dimming control quantity within the window is less than or equal to a preset amplitude threshold; or the duration for which the dimming control quantity remains unchanged within the window is not less than a preset minimum duration. When the cumulative duration of valid samples within the window is lower than the preset minimum duration threshold, no new reference determination result is generated for this cycle, and the previous valid result is used and retried. Within the stable sampling window, the metering module continuously acquires measurement data for power calculation and calculates the current load power using the energy integral average of the entire cycle or an integer multiple thereof; when a sample with obvious distortion or exceeding the range is detected, it is discarded before recalculation. The controller performs statistical estimation on multi-cycle samples to obtain a calibrated power estimate and determines the reference power based on the conversion relationship between the current load power and the preset dimming level.

[0065] In one implementation, the conversion relationship is a proportional conversion; in another implementation, the conversion relationship is an inverse conversion of a preset mapping relationship, which can be a piecewise linear list or a lookup table. To improve the stability of the reference, the controller can repeat the above calibration process within a preset number of times. When the variation between consecutively obtained reference powers is less than or equal to a consistency threshold, the reference power is confirmed. The consistency threshold can be determined based on the measurement uncertainty or historical fluctuation range, and the number of repetitions is configured according to the desired confidence level. After the reference power is confirmed, it can optionally be written to a storage unit for subsequent reading and reuse; during the writing process, data integrity verification is performed, and an upper limit is set on the writing frequency. Calibration is paused in the event of overvoltage, overtemperature, or communication abnormalities, and the above process continues after the abnormality is resolved.

[0066] Regarding S102 above: In one embodiment, after receiving the target dimming level, the single-lamp controller reads the effective reference power during the power-on or reset phase and calculates the theoretical reference power accordingly. The controller pre-stores or receives mapping description information for power conversion from the host system. The mapping description information includes at least: mapping type, mapping parameters, dimming level caliber used during calibration, and effective time.

[0067] The controller first verifies the target dimming level value against the calibration scale. If valid, it inputs the reference power and the target dimming level into the conversion logic to obtain the theoretical reference power. In some implementations, the conversion logic is a proportional conversion, meaning that under a scale consistent with the calibration scale, the reference power scales proportionally with the target dimming level. In other implementations, the conversion logic is a preset mapping relationship, including a piecewise linear list or a lookup table, and the reference power can be determined between adjacent nodes according to the proportional relationship defined by the nodes. To ensure operational safety and calibration consistency, the controller applies range constraints to the conversion results. When the result exceeds the preset safety range, it applies saturation limits at the upper and lower limits, and maintains the reference power monotonically increasing with the target dimming level. The theoretical reference power serves as the target value for subsequent power error calculations and closed-loop adjustments. In cases of missing mapping description information, verification failure, or exceeding limits, the controller rolls back according to the priority order of "priority to upper-level distribution - secondly to local cache - default configuration as a fallback," and records the event for maintenance traceability.

[0068] For example, the single-lamp controller and the streetlight driver communicate via a DALI bus. The reference power generated during the power-on / reset phase is already valid. After receiving the target dimming level, the controller first verifies that the level specification is consistent with the calibration specification, for example, both using a percentage scale from 0% to 100%. When the upper-level controller sends a DALI setting, it first converts it to a percentage scale according to system rules. The controller reads the effective mapping description information, which is a piecewise linear relationship described by node pairs (the number and position of nodes are determined by configuration). If the mapping is valid, the controller looks up the table according to the node interval and determines the theoretical reference power according to the node weight; when the target level is exactly at a node, the node value is directly taken; when the target level is between two adjacent nodes, the reference value is determined according to the piecewise rules of that interval. To ensure operational safety, if the conversion result exceeds the preset power range, the controller performs saturation limiting according to the upper and lower limits and keeps the reference power monotonically increasing with the target dimming level.

[0069] Regarding S103 above: In one implementation, when the sampling window is determined to be a stable window, the controller initiates the power acquisition and error calculation process. When a stable sampling window is determined to be valid, the controller freezes the theoretical reference power corresponding to this window as the target value for this calculation; if mapping or parameter updates occur during the window period, they take effect in the next window to avoid changes in the target value within the same window. The metering module continuously acquires measurement data (voltage, current samples, or direct active power readings) for power calculation within this sampling window. The current load power can be calculated using the energy integral average of an entire cycle or an integer multiple thereof. When the cumulative duration of valid samples in the sampling window is lower than a preset minimum duration threshold, no new current load power and power error are generated for this cycle; the result of the previous valid cycle is used and the event is recorded; when the validity meets the threshold, the current load power for this cycle is output. The controller reads the frozen theoretical reference power and compares it with the current load power, defining the power error by the difference between the two; a positive value indicates that the current load power is higher than the theoretical reference power, and a negative value indicates that it is lower than the theoretical reference power. This power error serves as the input for subsequent closed-loop adjustment steps.

[0070] For example, a stable sampling window must satisfy at least one of the following conditions: the change in the dimming control quantity within the window is less than or equal to a preset amplitude threshold; or the duration for which the dimming control quantity remains unchanged within the window is not less than a preset minimum duration. The amplitude threshold can be set based on the high quantile of historical control quantity noise; the minimum duration can be determined as an integer multiple of the entire power grid cycle or as the steady-state time identified by a small step test.

[0071] For example, the current load power can be estimated using either a weighted average or median statistic with equal duration; when the sampling segment includes a dimming switching boundary neighborhood, a protection period can be set and samples from that period can be removed to reduce the impact of transients on the estimation.

[0072] For example, at night, the single-lamp controller receives a target dimming level of 40%. The system determines that the dimming control value has remained unchanged in the most recent whole cycle, satisfying the stable sampling window condition; the controller freezes the theoretical reference power at this time and accumulates effective samples over the next few whole cycles. After removing a small number of distorted samples near the switching boundary, the current load power is obtained by averaging the energy integral. If the accumulated effective sample time reaches a set threshold, the current load power of this cycle is output; then, the difference between this and the frozen theoretical reference power is calculated to obtain the power error, and this error is passed to the closed-loop adjustment step; if the samples are insufficient, the error and power results of the previous cycle are retained, waiting for the next stable window.

[0073] Regarding S104 above: In one embodiment, after obtaining the power error, the controller compares the absolute value of the power error with a dimming power error tolerance threshold. When the absolute value is greater than the threshold, a dimming correction process is initiated: the controller determines the adjustment direction of the dimming output based on the sign of the power error, and determines the adjustment amount for the current cycle from a preset error-adjustment mapping relationship based on the error amplitude; when the power error is positive, the dimming output is reduced, and when the power error is negative, the dimming output is increased. The adjustment amount is applied to the dimming execution unit, such as duty cycle, constant current setting, analog voltage, or bus level, and is constrained by the maximum step size and maximum rate of change, while also limiting the upper / lower limit range of the adjusted output. After completing one adjustment, the controller waits for the sampling conditions to be met, i.e., a stable sampling window is determined to be established, and then repeats the power acquisition and power error calculation; when the absolute value of the power error is less than or equal to the threshold, the current correction process ends, and the current dimming output remains unchanged; when it is still greater than the threshold, it continues to iterate in the above manner until convergence or a preset iteration upper limit is reached.

[0074] For example, a street light operates at a target dimming level of 40%. If the power error obtained within the most recent stable sampling window is positive and exceeds the tolerance threshold, the controller sets the adjustment direction to "reduction" and obtains the adjustment amount for the current cycle from the error-adjustment amount mapping, performing a reduction in the duty cycle. After the reduction, it waits for the next stable sampling window to be established and recalculates the power error. If the second error still exceeds the threshold but has decreased, the controller continues to reduce the error by outputting a smaller adjustment amount according to the mapping. If the third error falls within the threshold, the controller ends the current correction and maintains the current dimming output.

[0075] Regarding S105 above: During operation, the controller receives update instructions for updating the dimming power error tolerance threshold and / or the reference power. The new values ​​of the updated parameters undergo basic verification (including whether they are within the preset allowable range and whether the scale is consistent); if the verification fails, the update is rejected and the current value is maintained. The update takes effect in the next control cycle after the current stable sampling window ends. When the update item is the dimming power error tolerance threshold, the new threshold is used for subsequent power error comparisons; when the update item is the reference power, the theoretical reference power at the target dimming level is recalculated based on the reference power, and the closed-loop process continues. When two updates are received simultaneously within the same control cycle, they are processed sequentially according to the receiving order. Finally, the theoretical reference power is calculated using the updated reference power, and the error is determined using the updated threshold.

[0076] Optionally, the update includes writing the updated dimming power error tolerance threshold and / or the reference power into non-volatile memory.

[0077] In one implementation, after receiving an update command and completing a validity check, the controller writes the updated dimming power error tolerance threshold and / or reference power into a non-volatile memory for reuse after power failure. The non-volatile memory can be, for example, EEPROM, flash memory, or ferroelectric memory. The write process includes: determining the object to be written, such as the tolerance threshold or reference power; writing the new value along with metadata, for example, storing it in a structure of {parameter type, new value, version identifier, verification flag}; and immediately reading back and comparing the data after writing. If the verification matches, the update is considered successful; otherwise, the update is canceled and the original value remains unchanged. To reduce the risk of data inconsistency caused by power failure, alternating writing to the primary / backup area can be used. For example, the "backup area" is written first and verified, and then the "valid pointer / flag" is switched to the backup area; the previous "primary area" is retained as a historical version. To extend media lifespan, a minimum write interval can be set, for example, not less than a certain number of control cycles or a cumulative count threshold. The timing of parameter activation is consistent with S105, for example, it takes effect in the next control cycle after the current stable sampling window ends; if the write fails, the current valid parameters are continued to be used and the event is recorded.

[0078] Optional, see Figure 2 The flowchart of a method for determining the reference power provided in this application embodiment includes steps S201~S203, wherein:

[0079] S201: Under the preset dimming level, determine the calibration sampling window according to the determination conditions of the stable sampling window, and collect current load power samples for multiple cycles within the calibration sampling window;

[0080] S202: Perform statistical estimation on the sample to obtain the calibration power estimate;

[0081] S203: Based on the conversion relationship between the preset dimming level and power, convert the calibrated power estimate into the reference power.

[0082] In one implementation, the controller determines a calibration sampling window at a preset dimming level. This calibration sampling window is determined based on criteria for a stable sampling window; for example, the change in dimming control quantity within the window is less than or equal to a preset amplitude threshold, or the duration for which the dimming control quantity remains unchanged is not less than a preset minimum duration. Within the calibration sampling window, the metering module collects current load power samples over multiple periods. For example, power readings are acquired over several consecutive sampling periods, and a sample set is constructed based on the valid samples within the window. The controller performs statistical estimation on the samples to obtain a calibration power estimate; for example, mean processing or median statistics can be used to determine the representative power value corresponding to the window. If necessary, samples from different sampling periods can be weighted by equal duration before outputting the calibration power estimate. Based on the conversion relationship between the preset dimming level and power, the calibration power estimate is converted into a reference power. For example, in a proportional implementation, the calibrated power estimate is proportionally converted to obtain the reference power based on a scale consistent with the preset dimming level; another example is in an implementation using a preset mapping relationship, the calibrated power estimate is reverse-converted based on a piecewise linear table or lookup table to determine the reference power (when it falls between nodes, the value is taken according to the definition rules of that interval; when it falls at a node, the node value is taken directly).

[0083] For example, in a scenario where the preset dimming level is 50%, multiple power samples are collected within the calibration sampling window and statistical estimation is performed to obtain the calibrated power estimate; then, the power is converted according to the same scale as the preset level to obtain the reference power, which is used for the calculation of the theoretical reference power at the subsequent target dimming level.

[0084] Optional, see Figure 3 This application provides a flowchart of a method for converting a calibration power estimate into a reference power, including steps S301-S302, wherein: S301: In a neighboring level range centered on the preset dimming level, a trial disturbance with an amplitude less than or equal to a first microstep is injected into the dimming control quantity. The amplitude of the trial disturbance satisfies the constraint of the dimming power error tolerance threshold, and the duration of the trial disturbance satisfies the constraint of a preset flicker suppression threshold; and load power response data corresponding to the trial disturbance is collected within a calibration sampling window. The load power response data includes at least the current load power before the disturbance and the current load power after the disturbance; S302: Based on the relationship between the amplitude of the trial disturbance and the load power response data, the local slope of the power relative to the dimming control quantity at the preset dimming level is estimated, and a local linearization conversion is performed on the calibration power estimate accordingly to obtain the reference power.

[0085] Existing proportional conversion or lookup table mapping methods are prone to deviations when the dimming curve has nonlinear or plateau sections, resulting in a discrepancy between the reference power and the actual performance of the luminaire. Therefore, this embodiment employs a perturbation calibration method within the neighborhood of a preset dimming level. By injecting a small perturbation without inducing flicker perception, the local variation relationship between power and dimming control quantity is directly measured to obtain a more realistic reference power.

[0086] In step S301, within a neighboring level range centered on the preset dimming level, a trial disturbance with an amplitude less than or equal to the first micro-step is injected into the dimming control quantity. The neighboring level range is a small-scale level range set around the preset dimming level, used to perform micro-amplitude trials without deviating from that level. For example, the range half-width can be determined as a fixed proportion of the full range of the dimming control quantity, such as 1% to 2%; or the range width can be determined as several times the system's minimum adjustment step size, such as one or two minimum step sizes, or the range table can be issued by the upper-level system according to the lamp model.

[0087] Dimming control parameters are used to characterize the controller's dimming settings for the load, such as PWM duty cycle, DALI level, 0-10V analog voltage, or constant current setting. The method of injecting probing disturbances corresponds to the type of dimming control parameter: when using a PWM interface, a small duty cycle step can be sent to the PWM channel and maintained for at least one full grid cycle; when using a DALI bus, a step command can be sent to increase or decrease the minimum level; when using a 0-10V interface, micro-step voltage adjustment can be performed at the voltage output; when using a constant current setting, a small step can be superimposed on the set current. The amplitude of the probing disturbance is constrained by the dimming power error tolerance threshold to ensure that the impact of the disturbance on the average power does not exceed the allowable error; the duration of the probing disturbance is constrained by a preset flicker suppression threshold to ensure that the disturbance is imperceptible to the naked eye. The disturbance is triggered within the calibration sampling window to maintain consistent sampling. For example, the first microstep can be a portion of the minimum dimming step size corresponding to the relative power change not exceeding the error tolerance threshold; the duration can be selected as not less than one full grid cycle and not exceeding the duration corresponding to the flicker sensing threshold.

[0088] In step S301, load power response data corresponding to the test disturbance also needs to be collected within the calibration sampling window. The response data includes at least the current load power before and after the disturbance. The response data can be obtained by taking representative power values ​​for a steady-state interval before and after the disturbance. For example, the steady-state power for one grid cycle can be recorded before the disturbance, and the steady-state power for another grid cycle can be recorded after the disturbance ends; these two sets together constitute a set of "disturbance-response" paired samples. When enhanced stability is required, two to three sets of paired samples can be obtained within the same window for statistical analysis.

[0089] In step S302, the controller estimates the local slope of power relative to the dimming control amount at a preset dimming level based on the relationship between the amplitude of the trial disturbance and the load power response data. The local slope is used to characterize the local change trend of power with respect to the dimming control amount at the preset dimming level. For example, when only one micro-step disturbance is performed, the difference between the power after the disturbance and the power before the disturbance can be compared with the disturbance amplitude to obtain the local slope; when multiple paired samples exist, a representative value can be obtained by using either a weighted average or robust statistics.

[0090] The controller performs local linearization on the calibrated power estimate based on the local slope to obtain a reference power within the neighborhood of the preset dimming level. Local linearization refers to adjusting the calibrated power estimate within a locally approximate linear region based on known local variation relationships to normalize it to the power definition point of the preset dimming level. For example, in a scenario with a preset dimming level of 50%, a micro-perturbation is used to obtain representative power values ​​before and after the perturbation, along with the corresponding perturbation amplitude. After determining the local slope, the calibrated power estimate is converted to 50% to obtain the reference power. After the micro-perturbation is completed, the controller exits the perturbation trial process. If the obtained local slope meets the stability criterion, the current reference power is updated based on this, and subsequent steps are initiated. When the calibration sampling window is invalid or there are insufficient valid samples, no new conversion result is output; the previous valid value is used, and the process is retried in the next window.

[0091] In this way, by directly obtaining the local power change rate near the dimming level, the systematic deviation caused by the nonlinear section can be effectively suppressed; the obtained reference power is more in line with the actual characteristics of the lamp, which can reduce the number and magnitude of subsequent power error closed-loop adjustments and achieve rapid and stable convergence; at the same time, the micro-step and flicker constraints ensure that the disturbance process is imperceptible to the user, taking into account both control accuracy and lighting experience.

[0092] Optionally, the calculation of the theoretical reference power at the target dimming level includes: calculating the nominal theoretical reference power based on the reference power and the target dimming level according to a preset mapping relationship; collecting voltage and current data of a single lamp port in the neighborhood of the target dimming level, and performing active component projection of the grid fundamental wave on the voltage and current data to estimate the active equivalent admittance of the single lamp port; calculating the line transmission loss correction amount based on the active equivalent admittance and combined with the predicted load current determined by the nominal theoretical reference power; applying the line transmission loss correction amount to the nominal theoretical reference power to obtain the compensated theoretical reference power; and applying a monotonic projection constraint to the compensated theoretical reference power so that it remains monotonically constant with the target dimming level and falls within a preset compensation range.

[0093] In practice, the preset mapping relationship is used to characterize the correspondence between the reference power and the dimming level, and can be one of a proportional relationship, a piecewise linear relationship, or a lookup table relationship. For example, when a proportional relationship is used, the controller scales the reference power according to a scale consistent with the calibration aperture; when a piecewise linear or lookup table relationship is used, the controller can calculate the power at the target level based on the node weights between adjacent nodes. The calculated nominal theoretical reference power is used as the target value before compensation.

[0094] Voltage and current data for a single lamp port are collected within the neighborhood of the target dimming level. A "single lamp port" refers to the power interface between the single lamp controller and the load lamp; its port parameters reflect the comprehensive characteristics of the line and drive. The sampling frequency for the voltage and current data can be set according to the entire power grid cycle or an integer multiple thereof to ensure sampling coherence. The controller performs active component projection of the power grid fundamental frequency onto the collected data, extracts the fundamental frequency component from the original signal, and calculates the active component accordingly to estimate the active equivalent admittance of the single lamp port. Here, "active equivalent admittance" characterizes the ratio of active current to voltage at the port at the fundamental frequency, reflecting the active power absorption capacity of the lamp under the current operating conditions. Through this estimation, field parameters for line compensation can be obtained.

[0095] The controller calculates the line transmission loss correction based on the aforementioned active equivalent admittance and the predicted load current determined by the nominal theoretical reference power. The line transmission loss correction characterizes the power loss caused by the line resistance and voltage drop between the luminaire and the controller, and its magnitude varies with the square of the load current. For example, on the same conductor, when the load current increases, the line voltage drop increases. The controller determines the correction amount using the aforementioned active equivalent admittance and predicted load current to compensate for this power loss.

[0096] The line transmission loss correction is applied to the nominal theoretical reference power to obtain the compensated theoretical reference power. Compensation can be additive or multiplicative to make the compensated result closer to the actual lamp power output. The compensated theoretical reference power is the final theoretical target value at the target level, used for subsequent power error calculations. A monotonic projection constraint is applied to the compensated theoretical reference power to ensure it remains monotonically increasing or constant with the target dimming level and falls within a preset compensation range. The "monotonic projection constraint" means forcing the calculated power-level curve to remain monotonically increasing or constant to avoid localized reverse fluctuations introduced by compensation. The preset compensation range can be configured by the system to ensure the safety and continuity of power changes.

[0097] For example, a single-lamp controller acquires port voltage and current waveforms via the DALI bus and performs fundamental component projection locally. The estimated active equivalent admittance is the comprehensive admittance value of the line and drive under the current environmental conditions. The controller uses this admittance in conjunction with the predicted load current corresponding to the target dimming level to calculate the line transmission loss correction, and applies it to the nominal theoretical reference power to obtain the compensated theoretical reference power. If the target dimming level is 80% and the line voltage drop is significant, the compensated theoretical reference power is slightly higher than the nominal value to offset the line loss. After monotonic projection processing, the compensation result ensures that the power-level curve increases continuously across the entire range. In this way, by introducing active equivalent admittance estimation based on port electrical parameters and line loss compensation, the theoretical reference power can be made closer to the actual lamp terminal power, reducing the impact of differences in line conditions and drive efficiency on the correction accuracy. After monotonic projection constraint, the power-level curve remains stable and monotonic, avoiding discontinuities or reverse changes caused by over-compensation, thereby improving the system dimming accuracy and operational stability.

[0098] Optionally, the calculation of the line transmission loss correction includes: forming a dominant line loss component by using the equivalent resistance of the line and the square of the current estimate used to calculate the line transmission loss correction, and the dominant line loss component accounts for a proportion of the line transmission loss correction within a preset current operating range that is not less than a preset lower limit.

[0099] Optionally, the calculation of the line transmission loss correction based on the active equivalent admittance and the predicted load current determined by the nominal theoretical reference power includes: determining the algebraic solution of the lamp terminal fundamental voltage based on the nominal theoretical reference power and the active equivalent admittance, according to the proportional relationship between the active power at the lamp terminal and the square of the lamp terminal fundamental voltage; determining the lamp terminal fundamental current based on the active equivalent admittance and the lamp terminal fundamental voltage; combining the line equivalent resistance with the square of the lamp terminal fundamental current to obtain the dominant component of the line transmission loss; substituting the dominant component into the power conservation relationship, making the controller terminal power equal to the sum of the lamp terminal power and the line transmission loss, and performing an algebraic solution under this relationship to obtain the line transmission loss correction; applying non-negativity constraints and preset upper and lower limit constraints to the line transmission loss correction, and ensuring that the line transmission loss correction remains monotonically constant with the target dimming level. Under actual wiring conditions, line transmission loss is dominated by components that increase with the square of the current. However, current network methods do not provide clear constraints on the proportion of the dominant component, which easily leads to undercompensation in low-current regions or overcompensation in high-current regions, causing non-physical fluctuations or monotonicity disruptions in the theoretical reference power. This implementation method limits the lower limit of the proportion of the dominant component of line loss, ensuring that the correction amount conforms to physical laws while maintaining numerical stability.

[0100] In specific implementation, the controller acquires the parameters required for calculating the line transmission loss correction, including at least: the line equivalent resistance and the current estimate used for the correction calculation. The line equivalent resistance can be recorded by maintenance personnel or issued by the upper-level system during the deployment phase, or it can be identified on-site through voltage-current measurements of known load conditions; the current estimate can be derived from the nominal theoretical reference power and the active equivalent admittance, or it can be obtained by port measurement if metering capabilities are available, and this application does not limit this. The dominant component of the line transmission loss is formed by the square of the line equivalent resistance and the current estimate. The dominant component is used to characterize the energy consumption caused by the conductor resistance, and it shows a trend of increasing with the square of the current. To avoid misjudging small additional losses (such as contact additional losses or frequency-related small components) as the main source, this embodiment uses this square term as the core term for the correction calculation.

[0101] The controller evaluates the proportion of the dominant component in the line transmission loss correction within a preset current operating range, ensuring that this proportion is not lower than a preset lower limit. The current operating range can be defined by the system configuration as a segment covering commonly used operating currents; the lower limit ensures that the correction is dominated by the square term, avoiding unreasonable negative compensation or non-monotonic changes in scenarios with small disturbances or noise dominance. When the proportion is detected to be lower than the lower limit, the controller can handle it in one of the following ways: preferentially using the dominant component as an approximation of the correction, triggering a re-identification of the line's equivalent resistance, or suppressing the weight of additional components; the specific strategy is determined by the system configuration and is not limited. The output line transmission loss correction that satisfies the above proportion constraint is used to apply the correction to the nominal theoretical reference power, obtaining the compensated theoretical reference power. This method maintains the physical consistency and numerical stability of the correction across the entire target dimming level range.

[0102] Thus, without altering the existing compensation framework, introducing dominant component proportion constraints can significantly reduce undercompensation in the low-current region and overcompensation in the high-current region, maintaining the monotonicity and smoothness of the reference power-level curve, and improving the convergence speed and stability of closed-loop correction. Furthermore, in field operation, using iterative or empirical table corrections often results in lengthy calculation links that easily introduce delays and uncertainties; a first-order algebraic solution method is needed to correlate lamp-end power, port parameters, and line losses under the same criteria, thereby reducing computational complexity and improving determinism.

[0103] In practical implementation, the algebraic solution of the lamp-end fundamental voltage can be determined based on the nominal theoretical reference power and the active equivalent admittance, according to the proportional relationship between the active power at the lamp end and the square of the lamp-end fundamental voltage. The nominal theoretical reference power is used to give the nominal value of the lamp-end power at the target level; the active equivalent admittance is used to characterize the active power absorption capacity of the port under the fundamental frequency. Through the correspondence between the two, the algebraic result of the lamp-end fundamental voltage can be determined without iteration. Based on the active equivalent admittance and the lamp-end fundamental voltage, the lamp-end fundamental current is determined. This current reflects the active power operation state of the lamp end at the target level and serves as the source of the current estimate for subsequent line transmission loss assessment. Combining the line equivalent resistance with the square of the lamp-end fundamental current yields the dominant component of the line transmission loss. This dominant component describes the power consumption caused by the conductor resistance and exhibits a non-linear increasing trend with the target level. Substituting the dominant component into the power conservation relationship, the controller-end power is made equal to the sum of the lamp-end power and the line transmission loss, and an algebraic solution is performed under this relationship to obtain the line transmission loss correction. This single algebraic solution directly yields the compensation amount that matches the nominal theoretical reference power, avoiding multiple iterations. Non-negativity constraints and preset upper and lower limits are applied to the line transmission loss correction, ensuring the correction amount remains monotonically constant with the target dimming level. Non-negativity ensures the compensation direction conforms to energy conservation; upper and lower limits limit overcompensation; and monotonically constant ensures the reference power-level curve has no reverse fluctuations across the entire range.

[0104] For example, the controller periodically collects port voltage and current waveforms within the target dimming level range, and performs fundamental active component projection to obtain the active equivalent admittance. At the 80% target level, the lamp terminal fundamental voltage is first determined based on the nominal theoretical reference power and active equivalent admittance, and then the lamp terminal fundamental current is obtained accordingly. This current is then combined with the known line equivalent resistance to obtain the dominant component of line loss. This dominant component is substituted into the power conservation relation for a first algebraic solution to obtain the correction amount. Subsequently, nonnegativity and upper and lower limit constraints and monotonic projection processing are performed to finally obtain the compensated theoretical reference power at that level.

[0105] In this way, replacing iterative compensation with a single algebraic solution not only reduces the complexity and latency of real-time calculations, but also ensures that the compensation results conform to physical and control standards across the entire range through triple constraints of nonnegativity, upper and lower limits, and monotonicity, thereby further improving the accuracy and stability of single-lamp dimming.

[0106] Optionally, calculating the power error between the current load power and the theoretical reference power includes: acquiring instantaneous active power samples of a single lamp port within a coherent accumulation window whose duration is an integer multiple of both the grid cycle and the dimming pulse cycle, and whose start and end points are aligned with the grid zero-crossing point; determining the first-order slope threshold of the instantaneous active power, adaptively expanding the neighborhood of each dimming upper and lower edge to form a boundary de-scratching zone, and removing samples within the boundary de-scratching zone; averaging the samples within the removed window to obtain an estimated value of the current load active power, and calculating the difference between this and the theoretical reference power to obtain the power error; calculating a beat frequency residual index, which characterizes the energy proportion of the instantaneous active power sample in the beat frequency band, and outputting the power error of the current cycle when the beat frequency residual index is less than or equal to a preset residual threshold, otherwise maintaining the power error of the previous effective cycle.

[0107] Furthermore, the frequency difference between the grid fundamental frequency and the dimming pulse will form a beat frequency component, and there are transient fluctuations near the upper and lower edges of the dimming. If the average is directly calculated within a fixed time window, the beat frequency and edge transients will be mixed into the power estimation, resulting in error jitter, closed-loop oscillation, or slow convergence.

[0108] Therefore, in this embodiment, a coherent accumulation window is first established. The duration of the coherent accumulation window is set to be an integer multiple of both the grid cycle and the dimming pulse cycle. For example, the duration corresponding to the least common multiple of the grid cycle and the dimming pulse cycle, or an integer multiple thereof, can be selected, and the start and end points of the coherent accumulation window are aligned with the grid zero-crossing point. The grid zero-crossing point can be obtained through the zero-crossing detection module of the port voltage, or through the sign transformation of voltage sampling combined with hysteresis criterion software detection. The dimming pulse cycle can be directly provided by the occurrence path of the dimming control quantity, such as the timer cycle of the PWM channel, the DALI bus gear change event, or it can be obtained by recording the timestamps of adjacent rising / falling edges. To avoid the target value changing within the same window, the theoretical reference power corresponding to this window can be frozen as the target value for this round of calculation when the window is established. The metering module acquires instantaneous active power samples of a single lamp port within this window; the instantaneous active power samples can be obtained by synchronously sampling voltage and current and converting them using energy caliber. The sampling frequency and processing caliber are not limited, as long as they are consistent with the aforementioned window cycle.

[0109] Boundary scrambling is then performed. Based on the first-order slope threshold of instantaneous active power, a boundary scrambling zone is adaptively expanded in the neighborhood of each dimming upper and lower edge, and samples within this zone are removed. The first-order slope threshold can be set based on historical noise statistics or configured by the host system. The adaptive expansion can be implemented as follows: starting from the timestamp of the upper (or lower) edge, it expands sample by sample to both sides until the slope of the samples at the boundary is continuously lower than the threshold and remains stable for a short time; when a reverse slope or transient fallback segment is detected, expansion continues until the stability criterion is met; the final width of the scrambling zone is determined by the threshold and the current sample changes, without the need for a preset fixed length. This allows for the complete removal of switching transients and their fallback segments.

[0110] After descrambling, the remaining valid samples within the window are averaged to obtain the current load active power estimate. The averaging method can be a weighted average with equal duration or an energy integral average. When the cumulative duration of valid samples within the window is lower than a preset minimum duration threshold, no new power estimate or power error is generated for this cycle; the result from the previous valid cycle is used, and the cycle is retried in the next window. The controller uses the difference between the current load active power estimate and the aforementioned theoretical reference power as the power error and uses this error as the input for closed-loop correction.

[0111] To suppress the impact of beat frequency, this embodiment calculates a beat frequency residual index, which characterizes the energy proportion of power samples within the beat frequency band in the window. The beat frequency band can be configured according to the difference frequency neighborhood between the grid frequency and the dimming fundamental frequency, and its bandwidth is set by system parameters. The beat frequency residual index can be obtained by performing bandpass energy statistics or short-time spectrum estimation on the samples within the window through the signal processing unit, and its value represents the proportion of beat frequency band energy to window energy. This index is compared with a preset residual threshold: when the beat frequency residual index is less than or equal to the threshold, the power error of the current cycle is output; when the beat frequency residual index is greater than the threshold, the power error of the previous effective cycle is maintained to avoid unreliable correction during the beat frequency dominant period.

[0112] The alignment of the coherent accumulation window can be accomplished by the zero-point detection circuit and the timer / comparator working together, or by the phase-locked software module based on the voltage sampling sequence. The slope threshold determination and adaptive expansion are executed by the MCU / DSP in the controller. The required input is the instantaneous active power sequence within the window and the rising / falling edge timestamps (if the timestamps cannot be obtained directly, the slope sign reversal point in the power sequence can be used as the edge marker). The calculation of the beat frequency residual index is completed by the algorithm module. Bandpass energy statistics or discrete spectrum estimation can be used, and the specific implementation is not limited.

[0113] In this way, the coherent accumulation window reduces out-of-cycle energy leakage by cohering with the power grid and dimming pulses; the boundary denoising based on the slope threshold can adaptively cover the upper / lower edges and their fallback segments without the need for a fixed protection width; and the beat frequency residual gating blocks unreliable outputs when the beat frequency ratio abnormally increases, avoiding error-driven overcorrection. With these three working together, the power error calculation becomes more robust, improving the convergence speed of closed-loop correction and reducing oscillations under complex operating conditions.

[0114] Based on the same inventive concept, this application also provides a single-lamp controller dimming accuracy correction system for a smart lighting system, corresponding to the single-lamp controller dimming accuracy correction method for a smart lighting system. Since the principle of the system in this application is similar to the single-lamp controller dimming accuracy correction method for a smart lighting system described above, the implementation of the system can refer to the implementation of the method, and the repeated parts will not be described again.

[0115] Reference Figure 4 The diagram shown is a schematic of a single-lamp controller dimming accuracy correction system for a smart lighting system provided in an embodiment of this application. The system includes:

[0116] The acquisition module 10 is used to acquire the dimming power error tolerance threshold and the reference power of the load lamp when the single lamp controller is powered on or reset; in response to the invalidity of the reference power, dimming is performed at the preset dimming level, the current load power is acquired, and the reference power is determined based on the current load power and the preset dimming level.

[0117] The first processing module 20 is used to calculate the theoretical reference power at the target dimming level based on the reference power.

[0118] The second processing module 30 is used to acquire the current load power within a sampling window that is determined to be stable, and to calculate the power error between the current load power and the theoretical reference power.

[0119] The correction module 40, in response to the absolute value of the power error being greater than the dimming power error tolerance threshold, adjusts the dimming output according to the sign of the power error; after each adjustment, it repeats the sampling and error calculation until the absolute value of the power error is less than or equal to the dimming power error tolerance threshold.

[0120] The update module 50, in response to receiving an update instruction for the dimming power error tolerance threshold or the reference power, updates the dimming power error tolerance threshold and / or the reference power.

[0121] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A method for correcting the dimming accuracy of a single-lamp controller in a smart lighting system, characterized in that, include: When the single lamp controller is powered on or reset, obtain the dimming power error tolerance threshold and the reference power of the load lamp. In response to the invalidity of the reference power, dimming is performed at a preset dimming level, the current load power is collected, and the reference power is determined based on the current load power and the preset dimming level; wherein, the determination of the invalidity of the reference power includes at least one of the following situations: not written or read failed, verification failed or the stored value exceeds the allowable range, the preset validity period has expired since the last calibration, a lamp replacement event is detected, or an abnormal operating environment is detected; For the target dimming level, the theoretical reference power at the target dimming level is calculated based on the reference power; Within a sampling window deemed stable, the current load power is acquired, and the power error between the current load power and the theoretical reference power is calculated; wherein the determination criterion for a stable sampling window is based on at least one of the following: The change in dimming control quantity within the sampling window is less than or equal to a preset amplitude threshold. The duration during which the dimming control value remains unchanged within the sampling window is not less than a preset minimum duration; In response to the absolute value of the power error being greater than the dimming power error tolerance threshold, the dimming output is adjusted according to the sign of the power error; sampling and error calculation are repeated after each adjustment until the absolute value of the power error is less than or equal to the dimming power error tolerance threshold. In response to receiving an update instruction for updating the dimming power error tolerance threshold, the dimming power error tolerance threshold is updated; in response to receiving an update instruction for updating the reference power, the reference power is updated.

2. The method for correcting the dimming accuracy of a single-lamp controller in a smart lighting system according to claim 1, characterized in that, The update includes: Write the updated dimming power error tolerance threshold and / or the reference power into the non-volatile memory.

3. The method for correcting the dimming accuracy of a single-lamp controller in a smart lighting system according to claim 1, characterized in that, Determining the reference power includes: Under the preset dimming level, a calibration sampling window is determined according to the determination criteria of the stable sampling window, and multiple cycles of current load power samples are collected within the calibration sampling window; Perform statistical estimation on the sample to obtain the calibration power estimate; Based on the conversion relationship between the preset dimming level and power, the calibrated power estimate is converted into the reference power.

4. The method for correcting the dimming accuracy of a single-lamp controller in a smart lighting system according to claim 3, characterized in that, The step of converting the calibrated power estimate into the reference power includes: Within a neighboring dimming level range centered on the preset dimming level, a trial disturbance with an amplitude less than or equal to the first microstep is injected into the dimming control quantity. The amplitude of the trial disturbance satisfies the constraint of the dimming power error tolerance threshold, and the duration of the trial disturbance satisfies the constraint of the preset flicker suppression threshold. Load power response data corresponding to the trial disturbance is collected within the calibration sampling window. The load power response data includes at least the current load power before the disturbance and the current load power after the disturbance. Based on the relationship between the amplitude of the trial disturbance and the load power response data, the local slope of the power relative to the dimming control amount at the preset dimming level is calculated, and the local linearization conversion is performed on the calibrated power estimate accordingly to obtain the reference power.

5. The method for correcting the dimming accuracy of a single-lamp controller in a smart lighting system according to claim 1, characterized in that, The calculation of the theoretical reference power at the target dimming level includes: According to the preset mapping relationship, the nominal theoretical reference power is calculated based on the reference power and the target dimming level; Within the neighborhood of the target dimming level, voltage and current data of a single lamp port are collected, and the active component projection of the grid fundamental wave is performed on the voltage and current data to calculate the active equivalent admittance of the single lamp port. Based on the active equivalent admittance and the predicted load current determined by the nominal theoretical reference power, the line transmission loss correction is calculated. The line transmission loss correction is applied to the nominal theoretical reference power to obtain the compensated theoretical reference power. A monotonic projection constraint is applied to the compensated theoretical reference power so that it remains monotonically constant with the target dimming level and falls within a preset compensation range.

6. The method for correcting the dimming accuracy of a single-lamp controller in a smart lighting system according to claim 5, characterized in that, The calculation of the line transmission loss correction includes: The line loss dominant component is formed by the square of the equivalent resistance of the line and the current estimate used to calculate the line transmission loss correction, and the proportion of the line loss dominant component to the line transmission loss correction is not less than a preset lower limit within a preset current operating range.

7. The method for correcting the dimming accuracy of a single-lamp controller in a smart lighting system according to claim 5, characterized in that, The calculation of the line transmission loss correction based on the active power equivalent admittance and the predicted load current determined by the nominal theoretical reference power includes: Based on the nominal theoretical reference power and the active equivalent admittance, and according to the fact that the active power at the lamp terminal is directly proportional to the square of the fundamental voltage at the lamp terminal, the algebraic solution of the fundamental voltage at the lamp terminal is determined. Based on the active equivalent admittance and the lamp terminal fundamental voltage, determine the lamp terminal fundamental current; The dominant component of line transmission loss is obtained by combining the equivalent resistance of the line with the square of the fundamental current at the lamp end. Substitute the dominant component into the power conservation relationship so that the power at the controller end is equal to the sum of the power at the lamp end and the line transmission loss. Then, perform an algebraic solution under this relationship to obtain the line transmission loss correction amount. A non-negative constraint and a preset upper and lower limit constraint are applied to the line transmission loss correction amount, and the line transmission loss correction amount is made monotonically constant with the target dimming level.

8. The method for correcting the dimming accuracy of a single-lamp controller in a smart lighting system according to claim 1, characterized in that, The calculation of the power error between the current load power and the theoretical reference power includes: The instantaneous active power sample of a single lamp port is obtained within a coherent accumulation window whose duration is an integer multiple of both the grid cycle and the dimming pulse cycle, and whose start and end points are aligned with the grid zero-crossing point. Based on the first-order slope threshold determination of the instantaneous active power, the neighborhood of each dimming upper and lower edge is adaptively expanded to form a boundary descrambling zone, and samples within the boundary descrambling zone are removed. The average value of the samples within the window after the removal is used to obtain the estimated value of the current load active power, and the difference between this value and the theoretical reference power is used to obtain the power error. Calculate the beat frequency residual index, which is used to characterize the energy proportion of the instantaneous active power sample in the beat frequency band. When the beat frequency residual index is less than or equal to a preset residual threshold, output the power error of the current cycle; otherwise, maintain the power error of the previous effective cycle.

9. A dimming accuracy correction system for a single-lamp controller in a smart lighting system, characterized in that, include: The data acquisition module is used to obtain the dimming power error tolerance threshold and the reference power of the load lamp when the single lamp controller is powered on or reset. In response to the invalidity of the reference power, dimming is performed at a preset dimming level, the current load power is collected, and the reference power is determined based on the current load power and the preset dimming level; wherein, the determination of the invalidity of the reference power includes at least one of the following situations: not written or read failed, verification failed or the stored value exceeds the allowable range, the preset validity period has expired since the last calibration, a lamp replacement event is detected, or an abnormal operating environment is detected; The first processing module is used to calculate the theoretical reference power at the target dimming level based on the reference power. The second processing module is used to acquire the current load power within a sampling window that is determined to be stable, and to calculate the power error between the current load power and the theoretical reference power; wherein the determination condition for the stable sampling window is based on at least one of the following: The change in dimming control quantity within the sampling window is less than or equal to a preset amplitude threshold. The duration during which the dimming control value remains unchanged within the sampling window is not less than a preset minimum duration; The correction module, in response to the absolute value of the power error being greater than the dimming power error tolerance threshold, adjusts the dimming output according to the sign of the power error; after each adjustment, it repeats the sampling and error calculation until the absolute value of the power error is less than or equal to the dimming power error tolerance threshold. The update module updates the dimming power error tolerance threshold in response to receiving an update instruction for updating the dimming power error tolerance threshold; and updates the reference power in response to receiving an update instruction for updating the reference power.

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