Time delay compensation type photovoltaic direct drive electrochromic glass adaptive control system and method

Abstract

The application discloses a time delay compensation type photovoltaic direct drive electrochromic glass self-adaptive regulation system and method, belongs to the technical field of building intelligent envelope and photovoltaic building integrated technology, and realizes driving signal generation through a control step integral trend operator and a time delay state variable, including collecting photovoltaic electric parameters and calculating output power, determining driving polarity through power change trend, and determining driving parameters in combination with power change intensity and glass state deviation; glass state is updated according to historical driving parameters, accumulated charge quantity and a time delay model, real-time transmittance is predicted, and the next control cycle driving signal is generated. Control oscillation caused by radiation fluctuation can be inhibited, response lag caused by ion migration and charge accumulation can be compensated, and the intelligent regulation level of the transparent electrochromic envelope structure is improved.

Description

Technical Field

[0001] This invention relates to the fields of building energy conservation, intelligent building envelope, building-integrated photovoltaics, electrochromic glass control, and building light and heat environment regulation. In particular, it relates to a time-delay compensated photovoltaic direct-drive electrochromic glass adaptive control system and method, specifically a photovoltaic direct-drive electrochromic glass adaptive control technology that incorporates the continuous chain of "solar radiation - photovoltaic output power - driving voltage - charge accumulation - extinction coefficient - spectral transmittance - solar heat gain" into the control logic. Background Technology

[0002] Transparent building envelopes serve as crucial interfaces for light and heat exchange between the interior and exterior of buildings. Ordinary architectural glass typically possesses fixed solar transmittance, shading coefficient, and heat transfer performance, making it difficult to adapt to dynamic changes in solar radiation intensity, solar altitude angle, weather variations, indoor illuminance requirements, glare risk, and air conditioning load demands. Electrochromic glass, under the influence of an applied low-voltage DC electric field, alters its spectral transmittance through ion insertion / extraction and redox reactions within the electrochromic material. This allows for dynamic adjustment of solar radiation transmittance during building operation, representing a significant technological approach for intelligent transparent building envelopes.

[0003] When solar radiation increases, it is necessary to reduce glass transmittance to decrease indoor solar heat gain, while simultaneously increasing the output power of photovoltaic power generation modules. These two factors have a natural matching relationship. Theoretically, using photovoltaic power generation modules to directly drive electrochromic glass can achieve energy self-sufficiency and environmental self-regulation in transparent building envelopes.

[0004] However, existing photovoltaic-driven electrochromic glass systems still have the following core technological shortcomings: 1. Existing technologies focus more on the physical integration of photovoltaic modules and electrochromic glass, and lack a systematic method for how to stably and reasonably convert photovoltaic output signals into electrochromic driving signals; 2. The system exhibits a significant dynamic response timing mismatch. The photovoltaic output power shows rapid fluctuations on the order of seconds; while the transmittance change of the electrochromic glass shows a delayed response on the order of minutes, indicating a mismatch in response rates. 3. Simply connecting the photovoltaic module directly to the electrochromic glass can cause rapid fluctuations in photovoltaic output, which can lead to frequent changes in the driving voltage. This can cause ions inside the electrochromic layer to be in a high-frequency reciprocating migration state, reducing transmittance stability and affecting device lifespan. 4. Photovoltaic power generation modules can only output unidirectional DC power, while the coloring and fading process of electrochromic glass requires a driving voltage of opposite polarity to achieve switching. Existing technology lacks an adaptation mechanism that can automatically switch the driving polarity according to the radiation change trend and the real-time state of the glass. 5. Existing system control methods treat the optical state of electrochromic glass as an instantaneous function of the current driving voltage, ignoring the effects of charge accumulation, ion diffusion, and response phase delay on transmittance evolution, resulting in inaccurate predictions of real-time transmittance and solar heat gain. 6. Existing PV-EC window systems typically do not fully incorporate the "solar radiation - photovoltaic output - driving voltage - extinction coefficient - transmittance - solar heat gain - indoor light and heat environment" as a continuous chain for adaptive control. Summary of the Invention

[0005] The purpose of this invention is to provide an adaptive control system and method for time-delay compensated photovoltaic direct-drive electrochromic glass. To solve the aforementioned problems in the prior art, this invention collects the output voltage and current of the photovoltaic power generation module and calculates the output power. Within a set control cycle, it obtains the power change rate or cumulative change and determines the polarity of the driving voltage of the electrochromic glass based on the power change trend. When the number of driving polarity switching times per unit time exceeds a threshold, the system enters an oscillation suppression mode. The unit time duration, switching time threshold, and minimum hold time can be calibrated and determined based on the ion migration response characteristics of the electrochromic device, the solar irradiance fluctuation law of the application scenario, and the building's solar thermal control accuracy requirements. The amplitude, duration, or duty cycle of the driving voltage are determined by combining the power change intensity and the glass target state deviation. Simultaneously, the glass state variables are updated based on historical driving parameters, cumulative charge, and response time delay model to predict real-time transmittance and generate the driving signal for the next control cycle, forming a closed-loop adaptive control logic.

[0006] This invention enables self-powered, low-oscillation, high-prediction-accuracy, and building-oriented adaptive adjustment of transparent building envelope structures, effectively improving system operational stability and device lifespan. To achieve the above objectives, this invention provides a time-delay-compensated photovoltaic direct-drive electrochromic glass adaptive control method, comprising the following steps: S1. Collect the output voltage and output current of the photovoltaic power generation module that provides direct drive power to the electrochromic glass, and calculate the photovoltaic output power; S2. Calculate the rate of change or cumulative change of photovoltaic output power within the set control period; S3. Determine whether solar radiation is enhanced, weakened, or stable based on the rate of change or the cumulative change. S4. Determine the polarity of the driving voltage for electrochromic glass based on the changes in solar radiation. S5. Determine the amplitude, duration, or duty cycle of the driving voltage based on the photovoltaic output power change rate, cumulative change, and the deviation between the current state and the target state of the electrochromic glass. S6. Estimate the current state of the electrochromic glass based on the historical driving voltage, historical driving current, cumulative charge, and response time delay model of the electrochromic glass; S7. Predict the real-time transmittance of the electrochromic glass based on the current state, and calculate the transmitted solar radiation or solar heat gain by combining the incident solar spectrum radiation. S8. Generate the drive signal for the next control cycle based on real-time transmittance, solar heat gain, and building light and heat environment targets, and execute the drive voltage output control of the electrochromic glass through the bipolar drive module.

[0007] Preferably, in each control cycle, the output voltage and output current of the photovoltaic power generation module are collected; the photovoltaic output power is calculated based on the measured voltage and current, or the photovoltaic output power is calculated through the photovoltaic equivalent diode model, and the photovoltaic power change, power change rate, or cumulative change within the control cycle at adjacent time points is further calculated; The photovoltaic output power can be calculated based on measured voltage and current, or using a photovoltaic equivalent diode model. The corresponding calculation formulas are as follows: ; In the formula, Let t be the photovoltaic output power; This refers to the output voltage of the photovoltaic system. This represents the photovoltaic output current; max indicates that the available output power can be selected based on the photovoltaic operating status or the maximum power point tracking logic. ; In the formula, This is the photovoltaic output current; It is the photocurrent, the magnitude of which is related to the real-time irradiance; This is the diode's reverse saturation current, which is related to the battery temperature. This refers to the output voltage of the photovoltaic system. This is the equivalent series resistance; The equivalent parallel resistance is given; A is the modification ideal factor or equivalent thermal voltage related parameter; first solve... , Then substitute the values ​​into the above formula to obtain the photovoltaic output power; The base drive control voltage is calculated based on the power change rate and integral trend. The calculation formula is as follows: ; In the formula, This is the control voltage input to the electrochromic glass drive circuit; is the power response amplification factor, used to adjust the proportional relationship between the photovoltaic power trend and the driving voltage intensity; sgn is the sign function, outputting +1 when the photovoltaic power change rate is positive, corresponding to the coloring polarity; outputting -1 when the photovoltaic power change rate is negative, corresponding to the fading polarity; outputting 0 when the photovoltaic power change rate is 0 or within the set dead zone threshold range, corresponding to the system hold mode; To control the time step; For integration variables; The driving voltage amplitude is influenced by the trend of photovoltaic output power variation. The absolute value and the deviation of the target state of the electrochromic glass The target state can be determined jointly by factors such as indoor illuminance, glare control, solar heat gain, or user-defined transmittance requirements. The cumulative change is the integral or discrete cumulative value of the change in photovoltaic output power within the set control cycle. The current state of the electrochromic glass is determined by the cumulative charge obtained by integrating the historical driving current. Defined; Building light and heat environment targets include one or more of the following: indoor illuminance, glare control, solar heat gain, indoor temperature, air conditioning load, or user-defined transmittance.

[0008] Preferably, the solar radiation state is determined based on the power change rate or cumulative change, and the polarity of the electrochromic glass driving voltage is determined based on the solar radiation change state. Specific operating steps include: When the photovoltaic power trend is greater than the positive threshold, it is determined that the solar radiation is enhanced, a coloring instruction is generated, and the driving voltage polarity is set to the first polarity. When the photovoltaic power trend is less than the negative threshold, it is determined that the solar radiation is weakening, a fading command is generated, and the driving voltage polarity is set to the second polarity. When the photovoltaic power trend is between positive and negative thresholds, it is determined that the change in solar radiation is not significant, and the system enters the hold mode.

[0009] Preferably, based on the ion migration characteristics and charge accumulation effect of electrochromic materials, a response time delay model is introduced. This model includes a phase delay factor to describe the delayed evolution of the material's optical state after the application of an electrical signal. The phase delay factor is theoretically calculated based on the ion diffusion kinetics formula and calibrated and corrected by combining the material's temperature characteristics and the measured response time. Through this phase delay factor, the control module corrects the update speed of the state variables, avoiding treating the color change process of the electrochromic glass as instantaneous. The response time-delay model solves for the rate of change of the extinction coefficient using formulas including, but not limited to, those in the following forms: ; In the formula, For the j-th state or the j-th layer of electrochromic material at wavelength The extinction coefficient at time t; It is a phase retardation factor, which can be related to the effective ion diffusion coefficient and the thickness of the electrochromic layer; To control the input voltage; This is the state transition threshold voltage; This is the spectral modulation weighting factor; The spectral temperature response coefficient is T(t); T(t) is the temperature of the electrochromic material at time t. Reference temperature; Based on the state variable or extinction coefficient after response time delay correction, the transmittance at different wavelengths is calculated using either an exponential decay form, an experimentally calibrated lookup table model, a dual-band fitting model, or an equivalent model of a non-uniform layer structure. The formula for the exponential decay form is as follows: ; In the formula, wavelength Spectral transmittance at time t; is the material extinction coefficient after time lag correction; x is the equivalent optical path length or effective thickness of the electrochromic layer in the material. The transmittance change of electrochromic glass is not an instantaneous function of the current driving voltage, but is determined by ion migration, charge accumulation, material diffusion, and temperature. The real-time transmittance of the electrochromic glass at different wavelengths is calculated based on the extinction coefficient after time-delay correction, and the transmitted solar radiation or solar heat gain is calculated in conjunction with the incident solar spectrum. Solar heat gain is used to determine the glass's coloring / fading depth, correct the target state and driving parameters for the next control cycle, and also serves as a constraint for building thermal environment regulation and air conditioning load optimization. The formula for calculating solar heat gain based on real-time transmittance is as follows: ; In the formula, I represents the amount of solar radiation transmitted or the solar heat gain at time t. The intensity of the incident solar spectrum radiation; This represents the real-time spectral transmittance; the integration limits of 280nm and 2500nm correspond to the main active bands of the solar spectrum.

[0010] Preferably, when the photovoltaic power is detected to change frequently between positive and negative in a short period of time, or the driving polarity is frequently switched within a unit of time, the system enters the oscillation suppression mode. The oscillation suppression mode can take one or more of the following measures: extending the control step size, increasing the power change dead zone threshold, setting a minimum hold time, prohibiting reverse drive in a short period of time, reducing the driving voltage amplitude, or entering the hold mode. The control module outputs control commands to the bipolar drive module based on the generated drive signal. The bipolar drive module outputs a first polarity or second polarity drive voltage to the electrochromic glass based on the control commands. The power conditioning and buffering module completes voltage limiting, current limiting, and filtering. When the glass reaches the target transmittance or the drive time reaches the set upper limit, the voltage output stops. The control module collects measured data on the transmittance, transmission spectrum, drive current, indoor illuminance, and glass surface temperature of the electrochromic glass and performs closed-loop correction on the state estimation model. When the deviation between the model's predicted state and the measured state exceeds a set threshold, the material response time constant, phase delay factor, spectral modulation weight, temperature response coefficient, or charge efficiency parameter is corrected.

[0011] Preferably, the time-delay compensated photovoltaic direct-drive electrochromic glass adaptive control system includes: a photovoltaic power generation module, an energy acquisition and power calculation module, an energy conditioning and buffering module, a bipolar drive module, an electrochromic glass module, a status detection module, a signal conversion control module, and a response time-delay compensation module. Photovoltaic power generation modules are used to convert solar radiation into direct current (DC) electricity. The power acquisition and power calculation module is connected to the photovoltaic power generation module and the signal conversion control module respectively. It is used to acquire the output voltage and output current of the photovoltaic power generation module, calculate the photovoltaic output power, and output the trend of photovoltaic output power change to the signal conversion control module. The power conditioning and buffering module is connected to the photovoltaic power generation module and is used to stabilize, limit, current limit and buffer the photovoltaic output; The bipolar drive module is connected to the electrochromic glass module and is used to output a first polarity coloring drive voltage or a second polarity fading drive voltage to the electrochromic glass module. The electrochromic glass module is connected to the bipolar drive module and is used to receive the first polarity or second polarity drive voltage output by the bipolar drive module. The status detection module is connected to the response delay compensation module and is used to collect the system operating status and building environment status, and output the collected status data to the response delay compensation module. The signal conversion control module is connected to the power acquisition and power calculation module. It receives the photovoltaic output power change trend signal from the power acquisition and power calculation module and converts the photovoltaic output power change trend into the driving voltage polarity, driving intensity and driving duration of the electrochromic glass. The response delay compensation module is connected to the state detection module and the signal conversion control module to form a bidirectional data interaction link. The signal conversion control module outputs drive command information in the forward direction, and the response delay compensation module sends back state variables and transmittance prediction results in the reverse direction to form a closed-loop control logic. It is used to receive drive-related information output by the signal conversion control module and state feedback data output by the state detection module. It updates the state variables of the electrochromic glass according to the historical drive voltage, historical drive current, cumulative charge and response delay model of the electrochromic glass module, and predicts the real-time transmittance of the electrochromic glass according to the state variables. The prediction results are fed back to the signal conversion control module to generate the drive signal for the next control cycle.

[0012] Preferably, the photovoltaic power generation module serves as both the driving energy source for the electrochromic glass and a natural sensing unit for changes in solar radiation; the power acquisition and power calculation module is used to acquire the output voltage and output current of the photovoltaic power generation module, and the photovoltaic power output by this module and its rate of change are input to the signal conversion control module; the power conditioning and buffering module is used to convert the fluctuating DC power output by the photovoltaic power generation module into safe driving power suitable for the operation of the electrochromic glass. Preferably, the photovoltaic power generation module can be a crystalline silicon photovoltaic module installed on the edge of the electrochromic glass, window frame, window wall or non-main lighting area, or a strip photovoltaic module, a semi-transparent thin film photovoltaic module, a transparent or semi-transparent perovskite photovoltaic module on the upper or side of the window, or a photovoltaic module integrated with the sunshade, curtain wall keel, window frame profile or building facade component. The power conditioning and buffering module includes one or more of the following: DC / DC voltage regulator, voltage limiting unit, current limiting unit, reverse connection protection unit, bypass discharge unit, capacitor or supercapacitor buffer unit, maximum power point tracking or approximate power tracking unit, undervoltage holding unit, and low radiation protection unit.

[0013] Preferably, the response delay compensation module is used to receive drive-related information output by the signal conversion control module, and at the same time receive feedback data sent by the status detection module; the bipolar drive module outputs a drive voltage of corresponding polarity according to the drive signal to drive the electrochromic glass module.

[0014] Preferably, the parameters collected by the status detection module may include the output voltage of the photovoltaic module, the output current of the photovoltaic module, the output power of the photovoltaic module, the driving voltage of the electrochromic glass, the driving current of the electrochromic glass, the cumulative injected or extracted charge of the electrochromic glass, the transmittance or transmission spectrum of the electrochromic glass, the illuminance of the indoor working surface, the indoor temperature, the outdoor solar radiation intensity, the inner and outer surface temperatures of the glass, the temperature of the photovoltaic cell, and the user's manual control commands. The electrochromic glass module includes a transparent conductive layer, an electrochromic layer, an ion-conducting layer, an ion-storage layer, an electrode lead-out terminal, and an encapsulation structure; the electrochromic glass module can be a monolithic glass component, an insulated glass component, a laminated glass component, a curtain wall glass unit, or a skylight component; the electrochromic glass module can be installed together with a photovoltaic power generation module in the same window frame, curtain wall unit, or transparent enclosure structure component; The bipolar drive module is one or more of the following: H-bridge circuit, polarity switching relay, semiconductor switch array, and bidirectional DC / DC circuit, to achieve polarity switching drive; For building curtain wall scenarios containing multiple PV-EC glass units, each window unit is set as an independent control node. Each independent control node collects photovoltaic output power and indoor local illuminance through its own status detection module, and performs local control according to its own power trend and state variables. The signal conversion control module also includes a host control unit, which is used to set differentiated control thresholds and weights for PV-EC units with different orientations, heights, or areas according to the overall illuminance distribution of the building, air conditioning load, and user preferences, so as to realize multi-window zone coordinated adjustment.

[0015] Therefore, the beneficial effects of the above-mentioned time-delay compensated photovoltaic direct-drive electrochromic glass adaptive control system and method are as follows: 1. This invention not only utilizes photovoltaic modules to provide driving energy for electrochromic glass, but also uses the trend of photovoltaic output power change as a natural sensing signal of solar radiation disturbance, reducing dependence on external radiation sensors and building power grids.

[0016] 2. This invention establishes the conversion relationship between the photovoltaic output power change trend and the electrochromic drive signal, determines the drive polarity by the sign of the power change rate or the cumulative trend amount, and determines the drive amplitude or duration by the power trend intensity and the target state deviation.

[0017] 3. This invention introduces the integral or cumulative trend of power change within the control step, which can suppress control oscillations caused by cloud shadows, shading and transient fluctuations in solar radiation, and avoid high-frequency reciprocating migration of ions inside the electrochromic layer.

[0018] 4. This invention achieves active control of the coloring and fading directions through a bipolar drive module, solving the mismatch between the unidirectional DC output of photovoltaics and the bidirectional adjustment requirements of electrochromic glass.

[0019] 5. This invention defines the transmittance state of electrochromic glass as a state variable that evolves with historical driving voltage, driving current and accumulated charge, rather than an instantaneous function of the current voltage, thereby improving the accuracy of glass transmittance prediction.

[0020] 6. This invention describes the hysteresis evolution of the extinction coefficient of electrochromic materials based on the phase delay factor and response time delay model, which can compensate for the time scale mismatch between the rapid change of photovoltaic output and the slow response of electrochromic materials.

[0021] 7. The present invention further calculates the real-time transmittance and solar heat gain at different wavelengths based on the extinction coefficient after time delay correction, so that the control of PV-EC glass can directly serve building lighting, glare control and air conditioning load reduction.

[0022] 8. This invention sets up multiple operating modes such as coloring, fading, holding, protection, and manual priority, which can improve system reliability, user acceptance, and device life.

[0023] 9. This invention is applicable to building exterior windows, glass curtain walls, skylights, sunrooms, building-integrated photovoltaic components, and other transparent or semi-transparent enclosure structures.

[0024] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0025] Figure 1 This invention provides an overall flowchart of a time-delay compensated photovoltaic direct-drive electrochromic glass adaptive control system and method. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages disclosed in the embodiments of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of the embodiments of the present invention and are not intended to limit the scope of the present invention. All other claims for protection obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are protected. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout.

[0027] It should be noted that the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, such as a process, method, system, product, or server that includes a series of steps or units, not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such process, method, product, or device.

[0028] The following is in conjunction with the appendix Figure 1 The embodiments of the present invention will be described in detail below.

[0029] Example 1: Basic photovoltaic direct-drive electrochromic window system: This embodiment uses electrochromic glass for building windows equipped with strip photovoltaic modules as the control object to achieve adaptive control of the entire process of light and heat environment under photovoltaic direct drive, taking into account response time delay.

[0030] An exterior window for buildings includes a window frame, electrochromic glass, strip photovoltaic modules, a power conditioning and buffering module, a supercapacitor, an H-bridge polarity switching circuit, a controller, and an illuminance sensor. The strip photovoltaic modules are installed on the upper part of the window frame or in the shading area of ​​the glass edge, with the photovoltaic module area accounting for 5% to 20% of the total window area, balancing power generation capacity and building lighting requirements. Its output is connected to the power conditioning and buffering module. The power conditioning and buffering module includes a DC / DC voltage regulator unit, a current limiting unit, and a supercapacitor buffer unit. The supercapacitor is used to maintain the operation of the controller and polarity switching circuit during short-term shading or irradiance fluctuations. The supercapacitor capacity can be selected from 0.1F to 10F, and the rated voltage matches the operating voltage of the drive circuit. The two transparent conductive electrodes of the electrochromic glass are connected to the H-bridge polarity switching circuit. The device's driving voltage operates within the range of ±1.5V to ±5V, which is within the safe driving range of conventional electrochromic devices. The specific operation steps for the full-process adaptive control are as follows: Step 1: The controller collects the output voltage and current of the photovoltaic module and calculates the photovoltaic output power. Further, it calculates the rate of change or cumulative change of the photovoltaic output power within a set control period. The set control period ranges from 30s to 300s and can be adjusted according to the solar thermal response accuracy requirements of the building scenario. The photovoltaic output power can be calculated based on the measured voltage and current, or it can be calculated using a photovoltaic equivalent diode model. The corresponding calculation formulas are as follows: ; in, Let t be the photovoltaic output power; This refers to the output voltage of the photovoltaic system. This represents the photovoltaic output current; max indicates that the available output power can be selected based on the photovoltaic operating status or the maximum power point tracking logic. ; in, This is the photovoltaic output current; It is the photocurrent, the magnitude of which is related to the real-time irradiance; This is the diode's reverse saturation current, which is related to the battery temperature. This refers to the output voltage of the photovoltaic system. This is the equivalent series resistance; The equivalent parallel resistance is given; A is the modification ideal factor or equivalent thermal voltage related parameter; first solve... , Then substitute the values ​​into the above formula to obtain the photovoltaic output power; The base drive control voltage is calculated based on the power change rate and integral trend. The calculation formula is as follows: ; in, This is the control voltage input to the electrochromic glass drive circuit; is the power response amplification factor, used to adjust the proportional relationship between the photovoltaic power trend and the driving voltage intensity; sgn is the sign function, outputting +1 when the photovoltaic power change rate is positive, corresponding to the coloring polarity; outputting -1 when the photovoltaic power change rate is negative, corresponding to the fading polarity; To control the time step; For integration variables; Step 2: Determine the driving polarity based on the power trend; When the photovoltaic power shows an increasing trend during the continuous control cycle and the indoor illuminance exceeds the set upper limit, the controller outputs a coloring command, and the H-bridge circuit applies a first polarity voltage to the electrochromic glass; when the photovoltaic power shows a decreasing trend and the indoor illuminance is lower than the set lower limit, the controller outputs a fading command, and the H-bridge circuit applies a second polarity voltage; when the indoor illuminance is within the set range, the system stops outputting the drive voltage, keeping the electrochromic glass in its current state. When the number of drive polarity switching times per unit time exceeds the threshold, the system enters oscillation suppression mode. The unit time can be set to 5-30 minutes, and the switching number threshold can be 2-5 times. The power change dead zone threshold is set to 2%-10% of the photovoltaic rated power; the minimum hold time is set to 60-600 seconds. The oscillation suppression mode can adopt one or more of the following measures: extending the control step size, increasing the power change dead zone threshold, setting the minimum hold time, prohibiting reverse drive in a short period of time, reducing the drive voltage amplitude, or entering hold mode. Oscillation suppression is monitored and executed in parallel throughout the entire process.

[0031] Step 3: Based on the absolute value of the photovoltaic power trend, available photovoltaic power, current state of the electrochromic glass, target state, and building solar thermal environment target, determine the driving voltage amplitude, driving duration, or duty cycle. The driving voltage amplitude is jointly determined by the absolute value of the photovoltaic output power change trend and the deviation of the electrochromic glass target state. The target state of the electrochromic glass can be determined based on indoor illuminance, glare threshold, solar heat gain limit, or user-set transmittance. The basic driving voltage is calculated based on the power change rate and integral trend, using the following formula: ; in, This is the control voltage input to the electrochromic glass drive circuit; It is the power response amplification factor, used to adjust the proportional relationship between the photovoltaic power trend and the driving voltage intensity; This is a sign function; it outputs +1 when the rate of change of photovoltaic power is positive, corresponding to the coloring polarity; and -1 when the rate of change of photovoltaic power is negative, corresponding to the fading polarity. To control the time step; It is the integral variable.

[0032] Step 4: Estimate the current state of the electrochromic glass. Based on the historical driving voltage, historical driving current, accumulated charge, material response time parameters, temperature parameters, optional transmittance feedback, and response time delay model, update the current state variables of the electrochromic glass. This state variable is not an instantaneous function of the current driving voltage, but is jointly determined by the historical driving process and material response characteristics.

[0033] Step 5: Predict the real-time transmittance of the electrochromic glass based on the current state; the spectral transmittance and solar heat gain calculation module calculates the real-time transmittance of the electrochromic glass at different wavelengths based on the extinction coefficient after time delay correction, and calculates the transmitted solar radiation or solar heat gain in combination with the incident solar spectral radiation. The rate of change of the extinction coefficient is solved using the response time-delay model according to the following formula: ; in, For the j-th state or the j-th layer of electrochromic material at wavelength The extinction coefficient at time t; It is a phase retardation factor, which can be related to the effective ion diffusion coefficient and the thickness of the electrochromic layer; To control the input voltage; This is the state transition threshold voltage; This is the spectral modulation weighting factor; This refers to the spectral temperature response coefficient. for Temperature of the electrochromic material at all times; Reference temperature; Based on the state variable or extinction coefficient after response lag correction, the transmittance at different wavelengths is calculated using the following formula: ; in, wavelength and Spectral transmittance at any given time; The material extinction coefficient after time lag correction; The equivalent optical path length or effective thickness of the electrochromic layer in the material; The solar heat gain is calculated based on real-time transmittance using the following formula: ; in, I represents the amount of solar radiation transmitted or the solar heat gain at time t. The intensity of the incident solar spectrum radiation; This represents the real-time spectral transmittance; the integration limits of 280nm and 2500nm correspond to the main active bands of the solar spectrum.

[0034] Step 6: Generate the drive signal for the next control cycle based on the real-time transmittance and the target building light and heat environment; the state detection module collects the transmittance, transmission spectrum, drive current, indoor illuminance or glass surface temperature of the electrochromic glass and corrects the state estimation model; when the glass reaches the target transmittance, stop outputting the drive voltage; if the deviation between the predicted state and the measured state exceeds the threshold, then correct the material response time constant, phase delay factor, spectral modulation weight, temperature response coefficient or charge efficiency parameter.

[0035] Example 2: Drive signal conversion method based on power change rate and integral trend: Within one control cycle, the controller collects the photovoltaic output power. The control step size is set, preferably from 1 minute to 10 minutes, but can also be set to several seconds to tens of minutes depending on the response time of the electrochromic device and the scene control accuracy requirements. The controller calculates the cumulative power change within this control step size. If the cumulative change is greater than the positive threshold, it indicates that the overall solar radiation is increasing, and the controller generates a first polarity driving voltage to color the glass; if the cumulative change is less than the negative threshold, it indicates that the overall solar radiation is decreasing, and the controller generates a second polarity driving voltage to fade the glass; if the cumulative change is between the positive and negative thresholds, it indicates that the change in solar radiation is not significant, and the system enters the hold mode.

[0036] Example 3: Glass state estimation method considering response time delay: The controller establishes a state variable for the electrochromic glass, which is determined by the historical driving voltage, historical driving current, accumulated charge, effective ion diffusion coefficient, and temperature correction coefficient. When the system applies a coloring voltage, the state variable does not instantaneously reach the target state, but rather increases gradually according to the material response time constant; when the system applies a fading voltage, the state variable gradually decreases according to the fading response time constant. The controller predicts the current transmittance of the glass based on this state variable and stops driving the system once the glass reaches the target state.

[0037] Example 4: Solar heat gain control method based on extinction coefficient and spectral transmittance: In a high-precision implementation, the system calculates the real-time extinction coefficient of the electrochromic material using a spectral sensor or model. The controller calculates the transmittance at different wavelengths based on the spectral attenuation relationship and further combines this with the incident solar spectral radiation to calculate solar heat gain. When solar heat gain exceeds a set threshold, the system increases the coloring target; when solar heat gain is below the set threshold and indoor illuminance is insufficient, the system enters a fading or high-transmittance state.

[0038] Example 5: Control methods for indoor light and heat environment in office buildings: This embodiment uses a south-facing window in an office building as a typical application example and is not intended to limit the scope of application of the invention. In the application scenario of a south-facing window in an office building, the target illuminance range for the indoor work surface is set to 300 lx to 2000 lx, and a solar heat gain control threshold is set. When the indoor illuminance is higher than 2000 lx or a glare risk is detected, the controller can enter a shading mode to reduce visible light transmittance, even if the photovoltaic power change trend is not obvious. When the indoor illuminance is lower than 300 lx and the photovoltaic power is low, the controller enters a fading mode or maintains a high transmittance state to improve the utilization rate of natural lighting. The invention is also applicable to various photovoltaic integrated transparent enclosure structures such as building glass curtain walls, skylights, sunrooms, and east-west oriented strong glare facades, and the control parameters can be adjusted according to the light and heat environment requirements of the corresponding scenario.

[0039] Example 6: Multi-window or curtain wall zoned collaborative control method: For building curtain walls containing multiple PV-EC glass units, the system can set each window unit as an independent control node. Each node collects its own photovoltaic output power and indoor local illuminance, and performs local control based on its own power trend and state variables. At the same time, the upper controller can set different control thresholds and weights for PV-EC units with different orientations, heights, or areas based on the overall illuminance distribution of the building rooms, air conditioning load, and user preferences, to achieve multi-window zoned coordinated adjustment.

[0040] In summary, through the above settings, the present invention can suppress control oscillations caused by transient solar radiation fluctuations, compensate for response hysteresis caused by ion migration and charge accumulation in electrochromic glass, and achieve self-powered, low-oscillation, predictable, and adaptive adjustment of the transparent envelope structure oriented towards the building's solar thermal environment.

[0041] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. An adaptive control method for time-delay compensated photovoltaic direct-drive electrochromic glass, characterized in that, Includes the following steps: S1. Collect the output voltage and output current of the photovoltaic power generation module that provides direct drive power to the electrochromic glass, and calculate the photovoltaic output power; S2. Calculate the rate of change or cumulative change of photovoltaic output power within the set control period; S3. Determine whether solar radiation is enhanced, weakened, or stable based on the rate of change or the cumulative change. S4. Determine the polarity of the driving voltage for electrochromic glass based on the changes in solar radiation. S5. Determine the amplitude, duration, or duty cycle of the driving voltage based on the photovoltaic output power change rate, cumulative change, and the deviation between the current state and the target state of the electrochromic glass. S6. Estimate the current state of the electrochromic glass based on the historical driving voltage, historical driving current, cumulative charge, and response time delay model of the electrochromic glass; Based on the ion migration characteristics and charge accumulation effect of electrochromic materials, a response time delay model is introduced. This model includes a phase delay factor to describe the delayed evolution of the optical state of the material after the application of an electrical signal. The phase delay factor is theoretically calculated based on the ion diffusion kinetics formula and calibrated and corrected by combining the material temperature characteristics and the measured response time. Through this phase delay factor, the control module corrects the update speed of the state variables to avoid treating the color change process of the electrochromic glass as instantaneous. The response time-delay model solves for the rate of change of the extinction coefficient using formulas including, but not limited to, those in the following forms: ； In the formula, For the j-th state or the j-th layer of electrochromic material at wavelength The extinction coefficient at time t; It is a phase retardation factor, which can be related to the effective ion diffusion coefficient and the thickness of the electrochromic layer; To control the input voltage; This is the state transition threshold voltage; This is the spectral modulation weighting factor; The spectral temperature response coefficient is T(t); T(t) is the temperature of the electrochromic material at time t. Reference temperature; S7. Predict the real-time transmittance of the electrochromic glass based on the current state, and calculate the transmitted solar radiation or solar heat gain by combining the incident solar spectrum radiation. Based on the state variable or extinction coefficient after response time delay correction, the transmittance at different wavelengths is calculated using either an exponential decay form, an experimentally calibrated lookup table model, a dual-band fitting model, or an equivalent model of a non-uniform layer structure. The formula for the exponential decay form is as follows: ； In the formula, wavelength Spectral transmittance at time t; is the material extinction coefficient after time lag correction; x is the equivalent optical path length or effective thickness of the electrochromic layer in the material. The transmittance change of electrochromic glass is not an instantaneous function of the current driving voltage, but is determined by ion migration, charge accumulation, material diffusion and temperature. The real-time transmittance of the electrochromic glass at different wavelengths is calculated based on the extinction coefficient after time-delay correction, and the transmitted solar radiation or solar heat gain is calculated in conjunction with the incident solar spectrum. Solar heat gain is used to determine the glass's tinting / fading depth, correct the target state and driving parameters for the next control cycle, and also serves as a constraint for building thermal environment regulation and air conditioning load optimization. The formula for calculating solar heat gain based on real-time transmittance is as follows: ； In the formula, I represents the amount of solar radiation transmitted or the solar heat gain at time t. The intensity of the incident solar spectrum radiation; Real-time spectral transmittance; the integration limits of 280nm and 2500nm correspond to the main active bands of the solar spectrum; S8. Generate the drive signal for the next control cycle based on real-time transmittance, solar heat gain, and building light and heat environment targets, and execute the drive voltage output control of the electrochromic glass through the bipolar drive module.

2. The adaptive control method for time-delay compensated photovoltaic direct-drive electrochromic glass according to claim 1, characterized in that, Within each control cycle, the output voltage and output current of the photovoltaic power generation module are collected; the photovoltaic output power is calculated based on the measured voltage and current, or the photovoltaic output power is calculated through the photovoltaic equivalent diode model, and the photovoltaic power change, power change rate, or cumulative change within the control cycle at adjacent time points is further calculated; The photovoltaic output power can be calculated based on measured voltage and current, or using a photovoltaic equivalent diode model. The corresponding calculation formulas are as follows: ； In the formula, Let t be the photovoltaic output power; This refers to the output voltage of the photovoltaic system. This represents the photovoltaic output current; max indicates that the available output power can be selected based on the photovoltaic operating status or the maximum power point tracking logic. ； In the formula, This is the photovoltaic output current; It is the photocurrent, the magnitude of which is related to the real-time irradiance; This is the diode's reverse saturation current, which is related to the battery temperature. This refers to the output voltage of the photovoltaic system. This is the equivalent series resistance; The equivalent parallel resistance is given; A is the modification ideal factor or equivalent thermal voltage related parameter; first solve... , Then substitute the values ​​into the above formula to obtain the photovoltaic output power; The base drive control voltage is calculated based on the power change rate and integral trend. The calculation formula is as follows: ； In the formula, This is the control voltage input to the electrochromic glass drive circuit; is the power response amplification factor, used to adjust the proportional relationship between the photovoltaic power trend and the driving voltage intensity; sgn is the sign function, outputting +1 when the photovoltaic power change rate is positive, corresponding to the coloring polarity; outputting -1 when the photovoltaic power change rate is negative, corresponding to the fading polarity; outputting 0 when the photovoltaic power change rate is 0 or within the set dead zone threshold range, corresponding to the system hold mode; To control the time step; For integration variables; The driving voltage amplitude is influenced by the trend of photovoltaic output power variation. The absolute value and the deviation of the target state of the electrochromic glass The target state can be determined jointly by factors such as indoor illuminance, glare control, solar heat gain, or user-defined transmittance requirements. The cumulative change is the integral or discrete cumulative value of the change in photovoltaic output power within the set control cycle. The current state of the electrochromic glass is determined by the cumulative charge obtained by integrating the historical driving current. Defined; Building light and heat environment targets include one or more of the following: indoor illuminance, glare control, solar heat gain, indoor temperature, air conditioning load, or user-defined transmittance.

3. The adaptive control method for time-delay compensated photovoltaic direct-drive electrochromic glass according to claim 1, characterized in that, The solar radiation state is determined based on the rate of change or cumulative change in power. The polarity of the driving voltage for the electrochromic glass is then determined based on the solar radiation state. The specific operating steps include: When the photovoltaic power trend is greater than the positive threshold, it is determined that the solar radiation is enhanced, a coloring instruction is generated, and the driving voltage polarity is set to the first polarity. When the photovoltaic power trend is less than the negative threshold, it is determined that the solar radiation is weakening, a fading command is generated, and the driving voltage polarity is set to the second polarity. When the photovoltaic power trend is between positive and negative thresholds, it is determined that the change in solar radiation is not significant, and the system enters the hold mode.

4. The adaptive control method for time-delay compensated photovoltaic direct-drive electrochromic glass according to claim 1, characterized in that, When the photovoltaic power is detected to change frequently in a short period of time, or the drive polarity is switched frequently within a unit of time, the system enters the oscillation suppression mode. The oscillation suppression mode can take one or more of the following measures: extend the control step size, increase the power change dead zone threshold, set the minimum hold time, prohibit reverse drive in a short period of time, reduce the drive voltage amplitude, or enter the hold mode. The control module outputs control commands to the bipolar drive module based on the generated drive signal. The bipolar drive module outputs a first polarity or second polarity drive voltage to the electrochromic glass based on the control commands. The power conditioning and buffering module completes voltage limiting, current limiting, and filtering. When the glass reaches the target transmittance or the drive time reaches the set upper limit, the voltage output stops. The control module collects measured data on the transmittance, transmission spectrum, drive current, indoor illuminance, and glass surface temperature of the electrochromic glass and performs closed-loop correction on the state estimation model. When the deviation between the model's predicted state and the measured state exceeds a set threshold, the material response time constant, phase delay factor, spectral modulation weight, temperature response coefficient, or charge efficiency parameter is corrected.

5. A time-delay compensated photovoltaic direct-drive electrochromic glass adaptive control system, characterized in that, The adaptive control method for time-delay compensated photovoltaic direct-drive electrochromic glass as described in any one of claims 1-4 includes: a photovoltaic power generation module, an energy acquisition and power calculation module, an energy conditioning and buffering module, a bipolar drive module, an electrochromic glass module, a state detection module, a signal conversion control module, and a response time-delay compensation module. The photovoltaic power generation module is used to convert solar radiation into direct current power. The power acquisition and power calculation module is connected to the photovoltaic power generation module and the signal conversion control module respectively. It is used to acquire the output voltage and output current of the photovoltaic power generation module, calculate the photovoltaic output power, and output the photovoltaic output power change trend to the signal conversion control module. The power conditioning and buffering module is connected to the photovoltaic power generation module and is used to stabilize, limit, limit and buffer the photovoltaic output. The bipolar driving module is connected to the electrochromic glass module and is used to output a first polarity coloring driving voltage or a second polarity fading driving voltage to the electrochromic glass module. The electrochromic glass module is connected to the bipolar drive module and is used to receive the first polarity or second polarity drive voltage output by the bipolar drive module. The status detection module is connected to the response time delay compensation module and is used to collect the system operating status and building environment status, and output the collected status data to the response time delay compensation module. The signal conversion control module is connected to the power acquisition and power calculation module, receives the photovoltaic output power change trend signal from the power acquisition and power calculation module, and converts the photovoltaic output power change trend into the driving voltage polarity, driving intensity and driving duration of the electrochromic glass. The response delay compensation module is connected to the state detection module and the signal conversion control module to form a bidirectional data interaction link. The signal conversion control module outputs drive command information in the forward direction, and the response delay compensation module sends back state variables and transmittance prediction results in the reverse direction to form a closed-loop control logic. It is used to receive drive-related information output by the signal conversion control module and state feedback data output by the state detection module. It updates the state variables of the electrochromic glass according to the historical drive voltage, historical drive current, cumulative charge and response delay model of the electrochromic glass module, and predicts the real-time transmittance of the electrochromic glass according to the state variables. The prediction results are fed back to the signal conversion control module to generate the drive signal for the next control cycle.

6. The time-delay compensated photovoltaic direct-drive electrochromic glass adaptive control system according to claim 5, characterized in that, The photovoltaic power generation module serves as both the driving energy source for the electrochromic glass and a natural sensing unit for changes in solar radiation. The power acquisition and power calculation module is used to acquire the output voltage and output current of the photovoltaic power generation module. The photovoltaic power output by this module and its rate of change are input to the signal conversion control module. The power conditioning and buffering module is used to convert the fluctuating DC power output by the photovoltaic power generation module into safe driving power suitable for the operation of the electrochromic glass.

7. The time-delay compensated photovoltaic direct-drive electrochromic glass adaptive control system according to claim 6, characterized in that, The photovoltaic power generation module may be a crystalline silicon photovoltaic module installed on the edge of electrochromic glass, window frame, window wall or non-main lighting area, or a strip photovoltaic module, semi-transparent thin film photovoltaic module, transparent or semi-transparent perovskite photovoltaic module on the upper or side of the window, or a photovoltaic module integrated with sunshade, curtain wall keel, window frame profile or building facade components. The power conditioning and buffering module includes one or more of the following: a DC / DC voltage regulator unit, a voltage limiting unit, a current limiting unit, a reverse connection protection unit, a bypass discharge unit, a capacitor or supercapacitor buffer unit, a maximum power point tracking or approximate power tracking unit, an undervoltage holding unit, and a low radiation protection unit.

8. The time-delay compensated photovoltaic direct-drive electrochromic glass adaptive control system according to claim 5, characterized in that, The response delay compensation module is used to receive drive-related information output by the signal conversion control module and feedback data sent by the status detection module; the bipolar drive module outputs a drive voltage of corresponding polarity according to the drive signal to drive the electrochromic glass module.

9. The time-delay compensated photovoltaic direct-drive electrochromic glass adaptive control system according to claim 5, characterized in that, The parameters collected by the status detection module may include the output voltage of the photovoltaic module, the output current of the photovoltaic module, the output power of the photovoltaic module, the driving voltage of the electrochromic glass, the driving current of the electrochromic glass, the cumulative injected or extracted charge of the electrochromic glass, the transmittance or transmission spectrum of the electrochromic glass, the illuminance of the indoor working surface, the indoor temperature, the outdoor solar radiation intensity, the inner and outer surface temperatures of the glass, the temperature of the photovoltaic cell, and the user's manual control commands. The electrochromic glass module includes a transparent conductive layer, an electrochromic layer, an ion-conducting layer, an ion-storage layer, an electrode lead-out terminal, and an encapsulation structure; the electrochromic glass module can be a monolithic glass component, an insulated glass component, a laminated glass component, a curtain wall glass unit, or a skylight component; the electrochromic glass module can be installed together with a photovoltaic power generation module in the same window frame, curtain wall unit, or transparent enclosure structure component. The bipolar drive module is one or more of the following: H-bridge circuit, polarity switching relay, semiconductor switch array, and bidirectional DC / DC circuit, to achieve polarity switching drive; For building curtain wall scenarios containing multiple PV-EC glass units, each window unit is set as an independent control node. Each independent control node collects photovoltaic output power and indoor local illuminance through its own status detection module, and performs local control according to its own power trend and state variables. The signal conversion control module also includes a host control unit, which is used to set differentiated control thresholds and weights for PV-EC units with different orientations, heights, or areas according to the overall illuminance distribution of the building, air conditioning load, and user preferences, so as to realize multi-window zone coordinated adjustment.

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