CN109863425B

CN109863425B - System and method for infrared cloud detector

Info

Publication number: CN109863425B
Application number: CN201780065447.9A
Authority: CN
Inventors: 贾森·策德利茨; 应宇阳; 王珏; 史蒂芬·克拉克·布朗
Original assignee: View Inc
Current assignee: View Inc
Priority date: 2016-10-06
Filing date: 2017-10-06
Publication date: 2022-07-01
Anticipated expiration: 2037-10-06
Also published as: TW201825929A; CA3039606A1; EP3523614A4; KR20190052140A; EP3523614A1; WO2018067996A1; KR102521230B1; TWI803468B; CN115144933A; CN109863425A; TW202334672A

Abstract

The present invention relates generally to an infrared cloud detector system and method for detecting a cloud volume condition. An infrared cloud detector system includes an infrared sensor, an ambient temperature sensor, and logic. The infrared sensor is configured to measure the sky temperature based on infrared radiation received within its field of view. The ambient temperature sensor is configured to measure an ambient temperature. And the logic is configured to determine a cloud condition based on a difference between the measured sky temperature and the measured ambient temperature.

Description

System and method for infrared cloud detector

Cross Reference to Related Applications

This application claims the benefit and priority of U.S. provisional application 62/453,407 entitled "infra red CLOUD DETECTOR SYSTEMS AND METHODS," filed on 2/1/2017, which is incorporated herein by reference in its entirety and for all purposes. This application is also a continuation-in-part application of International application PCT/US16/55709 (specifying the United states) entitled "MULTII-SENSOR", filed on 6.10.2016, which is a continuation-in-part application of U.S. patent application 14/998,019 entitled "MULTII-SENSOR", filed on 6.10.2015; both of these applications are incorporated by reference herein in their entirety and for all purposes. This application is also a continuation-in-part application of U.S. application 15/287,646 entitled "MULTII-SENSOR" filed on 6.10.2016, which is a continuation-in-part application of U.S. patent application 14/998,019 entitled "MULTII-SENSOR" and filed on 6.10.2015; both of these applications are incorporated by reference herein in their entirety and for all purposes.

Technical Field

The present disclosure relates generally to the provision of sensing elements for detecting cloud conditions, and in particular to an infrared cloud detector system and method for detecting cloud conditions thereof.

Background

Detecting clouds can be an important part of deciding to put equipment into operation at, for example, a robotic astronomical stage, as astronomers may want to detect clouds that may interfere with their observations. Conventional methods of mapping the sky to detect clouds rely on expensive imaging devices, which typically rely on measurements of visible light.

Disclosure of Invention

Certain aspects relate to infrared cloud detector systems and methods of detecting their cloudiness condition.

Certain aspects relate to an infrared cloud detector system. In some aspects, an infrared cloud detector system includes: an infrared sensor configured to measure sky temperature based on infrared radiation received within its field of view; an ambient temperature sensor configured to measure an ambient temperature; and logic configured to determine a cloud status based on a difference between the measured sky temperature and the measured ambient temperature.

In some aspects, an infrared cloud detector system includes: an infrared sensor configured to measure sky temperature based on infrared radiation received within its field of view; an ambient temperature sensor configured to measure an ambient temperature; a photoreceptor configured to measure an intensity of visible light; and logic configured to determine a cloud status. The logic is configured to determine a cloud status based on a difference between the measured sky temperature and the measured ambient temperature if a time of day is between a first time before sunrise and a second time after sunrise or between a third time before sunset and sunset. If the time of day is between a second time after sunrise and a third time before sunset, the logic is configured to determine the cloud status based on the measured intensity of visible light from the photoreceptor.

Certain aspects relate to infrared cloud detector methods. In some aspects, an infrared cloud detector method comprises: receiving a sky temperature reading from an infrared sensor and an ambient temperature reading from an ambient temperature sensor; calculating a difference between the sky temperature reading and the ambient temperature reading; and determining a cloud status based on the calculated difference between the sky temperature reading and the ambient temperature reading.

In some aspects, an infrared cloud detector method comprises: receiving a sky temperature reading from an infrared sensor, an ambient temperature reading from an ambient temperature sensor, and an intensity from a photoreceptor; and determining whether the time of day is: (i) between a first time before sunset and a second time after sunset or between a third time before sunset and sunset; (ii) between the second time after sunrise and a third time before sunset; (iii) after (i) and before (iii); or (iv) after (iii) and before (i). If the time of day is (i), (iii) or (iv), a cloud state is determined based on a difference between the measured sky temperature and the measured ambient temperature. If the time of day is (iii), the cloud status is determined based on the intensity readings received from the photoreceptors.

These and other features and embodiments are described in more detail below with reference to the accompanying drawings.

Drawings

Fig. 1 illustrates a schematic diagram of a side view of an infrared cloud detector system according to some implementations.

Fig. 2A shows a graph of two temperature readings over time taken by an infrared sensor of an infrared cloud detector according to this implementation.

Fig. 2B shows a graph of two ambient temperature readings obtained over time by the ambient temperature sensor of the infrared cloud detector discussed with respect to fig. 2A.

Fig. 2C shows two graphs of the calculated delta between the temperature reading obtained by the infrared sensor and the ambient temperature reading obtained by the ambient temperature sensor of the infrared cloud detector discussed with respect to fig. 2A and 2B.

Fig. 3 depicts a schematic (side view) of an infrared cloud detector system including an infrared cloud detector and a photoreceptor, according to an implementation.

Fig. 4A illustrates a perspective view of a diagram of an infrared cloud detector system including an infrared cloud detector in the form of a multisensor, according to an implementation.

Fig. 4B illustrates another perspective view of the infrared cloud detector system illustrated in fig. 4A including an infrared cloud detector in the form of a multisensor.

Fig. 4C illustrates a perspective view of some of the internal components of the multi-sensor device of the infrared cloud detector system illustrated in fig. 4A and 4B.

Fig. 5A is a graph with a plot of intensity readings taken over time by a visible light photoreceptor.

Fig. 5B is a graph having a plot of the difference between temperature readings taken over time by an infrared sensor and temperature readings taken over time by an ambient temperature sensor.

Fig. 6A is a graph with a plot of intensity readings taken over time by a visible light photoreceptor.

Fig. 6B is a graph having a plot of the difference between temperature readings taken by an infrared sensor over time and temperature readings taken by an ambient temperature sensor over time.

Fig. 7A is a graph with a plot of intensity readings taken over time by a visible light photoreceptor.

Fig. 7B is a graph having a plot of the difference between temperature readings taken by an infrared sensor over time and temperature readings taken by an ambient temperature sensor over time.

Fig. 8 shows a flow diagram describing a method of determining a cloud cover condition using temperature readings from an infrared sensor and an ambient temperature sensor, according to an implementation.

FIG. 9 shows a flow chart describing a method of determining a cloud volume condition using readings from an infrared sensor, an ambient temperature sensor, and a photoreceptor of an infrared cloud detector system, according to an implementation.

Fig. 10A depicts a schematic cross section of an electrochromic device.

Fig. 10B depicts a schematic cross section of an electrochromic device in a bleached state (or transitioning to a bleached state).

Fig. 10C depicts a schematic cross-section of the electrochromic device shown in fig. 10B but in a colored state (or transitioning to a colored state).

Fig. 11A illustrates a penetration depth of direct sunlight into a room through an electrochromic window between an exterior and an interior of a building including the room, according to an implementation.

Fig. 11B illustrates direct sunlight and radiation entering a room through an electrochromic window under clear sky conditions according to an implementation.

Fig. 11C illustrates radiated light from the sky when it may be blocked or reflected by objects such as clouds and other buildings, according to an implementation.

Fig. 12 is a flow diagram illustrating general control logic for a method for controlling one or more electrochromic windows in a building, according to an embodiment.

FIG. 13 is a schematic diagram showing a particular implementation of one of the blocks from FIG. 12, according to an implementation.

FIG. 14A is a flow diagram depicting a particular implementation of control logic for the operation shown in FIG. 13 according to an implementation.

FIG. 14B is a flow diagram describing a particular implementation of control logic for the operation shown in FIG. 14A according to an implementation.

Detailed description of the invention

I. Introduction to the word

At certain times of the day, the intensity of visible light is at a low level, for example in the early morning around sunrise and in the evening before sunset. The sensors calibrated to measure the intensity of visible light (referred to herein as a "visible light sensor" or "sensor" in general) do not detect direct sunlight, and their intensity measurements at these times of the day are not effective in determining when the sky is clear ("clear" state) and when the sky is cloudy ("cloudy" state). That is, visible light sensors pointed skyward at these times will measure low intensity values during both "sunny" and "cloudy" states. Therefore, the intensity measurements obtained by the visible light photoreceptor alone cannot be used to accurately distinguish between "cloudy" and "sunny" states at these times. If only the intensity measurements from the visible light photoreceptor are used to determine a "cloudy" condition (e.g., when the measured intensity level falls below a certain minimum), then an erroneous "cloudy" condition can be detected during the evening just before sunset. Similarly, visible light sensor measurements are ineffective in distinguishing "cloudy" and "clear" states just prior to sunrise in the absence of direct sunlight. At any of these time periods, the photoreceptor measurements may be used to detect an erroneous "cloudy" state. A controller that relies on an erroneous "cloudy" determination from such a photoreceptor reading may therefore implement inappropriate control decisions based on the erroneous "cloudy" determination. For example, if the photoreceptor reading determines an erroneous "cloudy" state just prior to sunrise, a window controller that controls the level of tint in an eastward optically switchable window (e.g., an electrochromic window) may improperly clear the window, allowing direct glare from the incipient sun to shine into the room.

Furthermore, the controller making decisions based primarily on current readings from the visible light photoreceptor does not take into account historical intensity levels in geographic areas that may be subject to possible current/future cloudiness conditions, e.g., to issue control commands in anticipation of conditions that may occur. For example, there may be historically low light levels in the morning as the cloudlets pass through the geographic area. In this case, temporarily blocking the small cloud of sunlight to the photoreceptor will result in the same determination of a "cloudy" state as when a large storm rolls into the area. In this case, the passage of the cloudiness may cause the controller to switch the tintable window and may lock the optically switchable window to an inappropriately low tint level until the window can transition to a higher (darker) tint level.

Infrared (IR) cloud detector

Both the cloud and the water vapor absorb and re-emit radiation in discrete bands across the Infrared (IR) spectrum. The cloud is generally warmer (has a higher temperature) than the clear sky, since the cloud absorbs and re-emits IR radiation and the clear sky transmits IR radiation. In other words, the presence of clouds typically produces an enhanced IR signal (which corresponds to an approximate blackbody spectrum at about ground temperature) over the signal from a clear sky. The effect of atmospheric humidity is also small, which may also produce enhanced IR signals, especially in low altitude areas. Based on these differences, the measured IR radiation can be used to detect cloud and "cloudy" conditions.

Various implementations relate to an infrared cloud detector and a method thereof for detecting cloud cover based on infrared readings. Infrared cloud detectors typically include at least one Infrared (IR) sensor and an ambient temperature sensor used in conjunction to obtain a temperature reading of the sky that may be used to detect a cloud condition. In general, the amount of infrared radiation emitted by the medium/object and then measured by the IR sensor varies depending on the temperature of the medium/object, the surface and other physical characteristics of the medium/object, the field of view of the infrared sensor, and the distance between the medium/object and the infrared sensor. The IR sensor converts IR radiation received within its field of view into a voltage/current and converts the voltage/current into a corresponding temperature reading (e.g., a digital temperature reading) of the medium/object within its field of view. For example, an IR sensor pointed (oriented) to face the sky outputs temperature readings of regions of the sky within its field of view. The IR sensor may be oriented in a particular direction (e.g., azimuth and elevation angles) to preferentially capture IR radiation in a geographic area of the sky within its field of view centered about that direction. An ambient temperature sensor measures the temperature of the ambient air surrounding the sensor. Typically, the ambient temperature sensor is positioned to measure the temperature of the ambient air surrounding the infrared cloud detector. The infrared cloud detector also includes a processor that determines a difference between temperature readings obtained by the IR sensor and the ambient temperature sensor and uses the difference to detect an amount of cloud cover in an area of the sky within a field of view of the IR sensor.

In general, the sky temperature readings obtained by ambient temperature sensors tend to fluctuate less than the sky temperature readings obtained by infrared radiation sensors as weather conditions change. For example, in a fast moving weather pattern, during an "intermittent overcast" condition, the sky temperature readings obtained by the infrared radiation sensors tend to fluctuate at a high frequency. According to equation 1, certain implementations of an infrared cloud detector have determining a temperature reading (T) of an infrared sensor_IR) And ambient temperature reading (T)_A) The logic of the difference delta (delta) therebetween to help normalize the temperature reading (T) of the infrared sensor_IR) Any fluctuation of (a). In one embodiment, the logic determines a "cloudy" state if delta (Δ) is determined to be above an upper threshold (e.g., about 0 degrees celsius), a "clear" state if delta (Δ) is determined to be below a lower threshold (e.g., about-5 degrees celsius), and an "intermittent cloudy" state if delta (Δ) is between the upper and lower thresholds. In another embodiment, the logic determines a "cloudy" state, if delta (Δ) is above a single threshold, the logic determines a "cloudy" state, and if delta (Δ) is below the threshold, the logic determines a "sunny" state. In one aspect, the logic may apply one or more correction factors to delta (Δ) before determining whether it is above or below a threshold. Some examples of correction factors that may be used in an implementation include humidity, sun angle/solar altitude angle, and field altitude. For example, a correction factor may be applied based on the height and density of the detected clouds. Lower altitude clouds and/or higher density cloud to ambient temperatures compared to infrared sensor readingsThe degree readings are more closely related. The higher altitude cloud and/or the lower density cloud correlates well with the infrared sensor readings and then with the ambient temperature readings. In this embodiment, a correction factor may be applied that weights higher ambient temperature readings for lower altitude clouds and/or higher density clouds, or weights infrared sensor readings for higher altitude clouds, and/or may use a lower density cloud. In another embodiment, a correction factor may be applied based on humidity and/or sun position to more accurately describe the cloud cover and/or remove any outliers. Technical advantages of using delta (Δ) to determine cloud state are illustrated with reference to fig. 2A-2C below.

Since the sky temperature readings are generally independent of the presence of direct sunlight, infrared cloud detectors may use the temperature readings to detect the cloud cover condition more accurately in some cases than visible light sensors may detect when the sunlight intensity is low (e.g., early in the morning just before and after sunrise, late afternoon before sunset). At these times, the visible light sensor may potentially detect a false "cloudy" condition. According to these implementations, infrared cloud detectors may be used to detect clouds and their accuracy of detection is independent of whether the sun is present or whether there is otherwise a low light intensity level, e.g. just before sunrise or sunset. In these implementations, a relatively low sky temperature generally indicates a likelihood of a "sunny" state, and a relatively high sky temperature reading generally indicates a likelihood of a "cloudy" state (i.e., cloud cover).

In various implementations, the IR sensor of the infrared cloud detector is calibrated to measure radiant flux of long wave infrared radiation within a particular range. The processor of the IR sensor or a separate processor may be used to infer temperature readings from these measurements. In one aspect, the IR sensor is calibrated to detect infrared radiation in a wavelength range between about 8 μm and about 14 μm. In another aspect, the IR sensor is calibrated to detect infrared radiation having a wavelength greater than about 5 μm. In another aspect, the IR sensor is calibrated to detect infrared radiation in a wavelength range between about 9.5 μm and about 11.5 μm. In another aspect, the IR sensor is calibrated to detect infrared radiation in a wavelength range between about 10.5 μm to 12.5 μm. In another aspect, the IR sensor is calibrated to detect infrared radiation in a wavelength range between about 6.6 μm to 20 μm. Some examples of the types of IR sensors that may be used include infrared thermometers (e.g., thermopiles), infrared radiometers, infrared atmospheric radiometers, infrared pyrometers, and the like. An example of a commercially available IR sensor is Melexis MLX90614 manufactured by Melexis of detroit, michigan. Another commercially available embodiment of an IR sensor is the TS305-11C55 temperature sensor manufactured by TE connectivity, Inc. of Switzerland. Another commercially available example of an IR sensor is the SI-111 infrared radiometer manufactured by Apogee temperature sensor manufactured by TE connection of Switzerland, Inc.

In various implementations, the infrared cloud detector has an IR sensor positioned and oriented such that its field of view may receive infrared radiation from a particular region of the sky of interest. In one implementation, the IR sensor may be located on the roof of a building and oriented with its sensing surface facing vertically upward or at a small angle to the vertical, such that its field of view is an area of sky above or at some distance from the building.

In certain implementations, the infrared cloud detector has a protective housing and the infrared sensor is located within the housing. The housing may have a cover with one or more holes or thinned areas that allow/limit the transmission of infrared radiation to the infrared sensor. In some cases, the cover may be made of a plastic such as polycarbonate, polyethylene, polypropylene, and/or a thermoplastic such as nylon or other polyamides, polyesters, or other thermoplastics, among other suitable materials. In one embodiment, the material is a weather resistant plastic. In other cases, the cover may be formed of a metal material such as aluminum, cobalt, or titanium, or a semi-metal material such as aluminum. In some implementations, the cover may be sloped or convex to prevent the accumulation of water. Depending on the type of material used to form the cover, the cover may be 3D printed, injection molded, or formed via another suitable process.

In some implementations, the cover includes one or more holes or thinned regions to increase transmission of incident radiation or other signals to the detectors within the housing (reduce blocking). For example, the cover may include one or more holes or thinned areas proximate to the infrared sensor in the housing to allow for improved transmission of incident infrared radiation to the infrared sensor. The holes or thinned areas may also improve the transmission of other signals (e.g., GPS signals) to other detection devices within the housing. Additionally or alternatively, some or all of the cover may be formed of a light diffusing material. In some implementations, the cap may be connected to the housing via an adhesive, or to some mechanical coupling mechanism, for example, by using a screw and thread approach or via a pressure washer or other crimp fitting.

The field of view of the sensing surface of the infrared sensor is defined by its material composition and its structure. In some cases, the field of view of the infrared sensor may be narrowed by an obstacle. Some examples of barriers include building structures such as overhanging or rooftop structures, barriers near a building such as trees, or other buildings, and the like. As another example, if the infrared sensor is located within the housing, structures within the housing may reduce the field of view.

In one aspect, a single IR sensor has a vertical unconstrained field of view that deviates from vertical by about 50 degrees to about 130 degrees ± 40 degrees. In one aspect, the IR sensor has a field of view in the range of 50 degrees and 100 degrees. In another aspect, the IR sensor has a field of view in the range of 50 degrees and 80 degrees. In another aspect, the IR sensor has a field of view of about 88 degrees. In another aspect, the IR sensor has a field of view of about 70 degrees. In another aspect, the IR sensor has a field of view of about 44 degrees. The field of view of an IR sensor is generally defined as a cone-shaped volume. IR sensors typically have a wider field of view than visible light sensors and are therefore able to receive radiation from a larger area of the sky. Since IR sensors can read readings of a large area in the sky, IR sensors are more useful in determining proximity conditions (e.g., an upcoming storm cloud) than visible light photoreceptors, which will be more limited to detecting current conditions in the immediate vicinity of the photoreceptor that affect its small field of view. In one aspect, a five sensor blocked IR sensor arrangement of mounted sensors (e.g., in a multi-sensor configuration) has four angularly mounted IR sensors, each constrained by a field of view of 20-70 degrees or 110-160 degrees, and one upwardly facing IR sensor constrained by a field of view of 70-110 degrees.

Certain IR sensors tend to measure sky temperature more effectively when direct sunlight does not strike the sensing surface. In certain implementations, the infrared cloud detector has a structure that blocks direct sunlight from the sensing surface of the IR sensor, or has a structure that diffuses direct sunlight before it illuminates the sensing surface of the IR sensor (e.g., a housing of opaque plastic). In one implementation, the IR sensor may be obscured by an overhanging structure of the building or an infrared cloud detector. In another implementation, the IR sensor may be located within a protective housing having a diffusing material between the sensing surface of the IR sensor and the sky to diffuse any direct sunlight from reaching the sensing surface of the IR sensor and also to provide protection from potentially harmful elements such as dirt, animals, etc. Additionally or alternatively, some implementations only use IR sensor readings obtained before sunrise or after sunset to avoid the possibility of direct sunlight illuminating the IR sensor. In these implementations, a photoreceptor reading or other sensor reading may be used to detect a cloudiness condition between sunrise and sunset.

In various implementations of the infrared cloud detector, there is an ambient temperature sensor for measuring the temperature of the air surrounding the ambient temperature sensor. Typically, an ambient temperature sensor is positioned in contact with the outdoor environment (e.g., located outside of a building) to obtain a temperature reading of the sky. The ambient temperature sensor may be, for example, a thermistor, thermocouple, resistance thermometer, thermocouple, silicon bandgap temperature sensor, or the like. An example of a commercially available ambient temperature sensor is a Pt100 thermometer probe manufactured by Omega. Certain implementations include an ambient temperature sensor positioned to avoid direct sunlight from striking its sensing surface. For example, the ambient temperature sensor may be located under an overhang or mounted under a structure that shields the ambient temperature sensor from direct sunlight.

Although many implementations of the infrared cloud detector described herein include one IR sensor and one ambient temperature sensor, it should be understood that other implementations may include more than one IR sensor and/or more than one ambient temperature sensor. For example, in one implementation, an infrared cloud detector includes two or more IR sensors for redundancy and/or to point the IR sensors to different areas of the sky. Additionally or alternatively, the infrared cloud detector may have two or more ambient temperature sensors for redundancy in another implementation. An embodiment of a system for detecting CLOUDs using two IR sensors directed at different areas of the sky can be found in international application PCT/US15/53041 entitled "sun DETECTION WITH DETECTION DISTANCE SENSING", filed on 29/9/2015, which is incorporated herein by reference in its entirety.

Various implementations of infrared cloud detectors have a basic function of detecting cloud cover conditions. In some cases, the infrared cloud detector may detect a "cloudy" state and a "sunny" state. Additionally, some implementations may further differentiate "cloudy" conditions as gradual transitions. For example, one implementation may distinguish a "cloudy" condition as "cloudy" or "intermittent cloud". In another embodiment, an implementation may designate different levels (e.g., 1-10) of cloudy days as being given a "cloudy" condition. In yet another embodiment, an implementation may determine a future cloud state. Additionally or alternatively, some implementations may also detect other weather conditions.

In various implementations, the infrared cloud detector includes a temperature sensor configured to obtain a temperature reading T_IRAnd is configured to obtain an ambient temperature reading T_AThe ambient temperature sensor of (1). The infrared cloud detector also includes one or more processors containing program instructions that are executable to perform various functions of the infrared cloud detector. ToThe processor executes the program instructions to determine the temperature difference delta (Δ) between the temperature readings as provided by equation 1. The processor also executes program instructions to determine a cloud cover condition based on delta (Δ). As described above, in some cases, using ambient temperature readings may help to normalize for any rapid fluctuations in the temperature readings of the IR sensor.

Delta (Delta) infrared sensor temperature reading (T)_IR)

Ambient temperature reading (T)_A) (equation 1).

In one implementation, a processor executes program instructions to compare delta (Δ) to an upper threshold and a lower threshold and determine a cloud condition. If delta (Δ) is above the upper threshold, a "sunny" state is determined. If delta (Δ) is below a lower threshold, a "cloudy" state is determined. If delta (Δ) is below the upper threshold and above the lower threshold (i.e., between the thresholds), a "intermittent" cloud cover condition is determined. Additionally or alternatively, when delta (Δ) is between thresholds, additional factors may be used to determine the cloud cover condition. This implementation works well in the morning and evening of the dusk of dawn hours to accurately determine a "cloudy" or "sunny" condition. Between sunrise and sunset, additional factors may be used to determine the cloud cover condition, for example, by using visible photoreceptor values. Some embodiments of other factors include: altitude, wind speed/direction and solar altitude/sun angle.

A. Infrared (IR) cloud detection sensor system

Fig. 1 illustrates a schematic diagram of a side view of a system having an infrared cloud detector 100 according to some implementations. The infrared cloud detector 100 comprises a housing 101, the housing 101 having a cover 102, the cover 102 having a hole or thinned portion 104 at a first surface 106 of the housing 101. The housing 101 also has a second surface 108 opposite the first surface 106. The infrared cloud detector 100 further includes: an IR sensor 110, said IR sensor 110 configured to obtain a temperature reading T based on infrared radiation received within its conical field of view 114_IR(ii) a An ambient temperature sensor 130, the ambient temperature sensor 130 for obtaining an ambient temperature reading T_A(ii) a And a processor 140, the processingThe IR sensor 110 and the ambient temperature sensor 130 are in communication (wired or wirelessly) with the processor 140. In one aspect, the IR sensor is one of an infrared thermometer (e.g., thermopile), an infrared radiometer, an atmospheric radiometer, and an infrared pyrometer. In one aspect, the ambient temperature sensor is one of a thermistor, a thermometer, and a thermocouple.

In fig. 1, the IR sensor 110 is located behind the hole or thinned portion 104 and within the outer shell of the housing 101. The aperture or thinned portion 104 enables the IR sensor 110 to measure infrared radiation that is transmitted through the aperture or thinned portion 104 and received at its sensing surface. The IR sensor 110 includes an imaginary axis 112, the imaginary axis 112 being orthogonal to the sensing surface of the IR sensor 110 and passing through the center of the IR sensor 110. In the illustrated embodiment, the IR sensor 110 is oriented such that its axis 112 is in a vertical orientation and the sensing surface faces upward. In other embodiments, the IR sensor 110 may be directed such that the sensing surface faces another orientation to direct the IR sensor to a particular area, such as the sky. The IR sensor 110 has a tapered field of view 114 through the aperture or thinned portion 104 to the exterior of the housing 102. In this embodiment, the portion of the cover 102 surrounding the aperture or thinned portion 104 is made of a material that blocks infrared radiation, and the perimeter of the aperture or thinned portion 104 defines the field of view 114. The view 114 of the field of view has an angle α and is centered about the axis 112. In fig. 1, the ambient temperature sensor 130 is positioned and secured to the second surface 108 of the housing 102 away from the edge to avoid direct sunlight from striking the ambient temperature sensor 130 when the infrared cloud detector 100 is in this orientation. Although not shown, infrared cloud detector 100 also includes one or more structures that hold infrared sensor 110 and other components in place within housing 101.

Infrared cloud detector 100 also includes logic to calculate a sky temperature reading (T) for the infrared sensor at each read time_IR) And ambient temperature reading (T)_A) Delta (Δ) in between, and determining a cloud cover condition based on the calculated delta (Δ). During operation, the IR sensor 110 obtains a temperature based on infrared radiation received from a region of the sky within its field of view 114Degree reading T_IRAnd the ambient temperature sensor 130 obtains an ambient temperature reading T of the ambient air surrounding the infrared cloud detector 100_A. The processor 140 receives the signal from the IR sensor 110 with a temperature reading T_IRAnd receives a signal having an ambient temperature reading T from the ambient temperature sensor 130_AOf the signal of (1). Processor 140 executes instructions stored in a memory (not shown) that uses this logic to calculate a temperature reading (T) of the infrared sensor at a particular time_IR) And ambient temperature reading (T)_A) Delta (Δ) in between to determine the cloud cover condition. For example, processor 140 may execute instructions that determine a "cloudy" state if delta (Δ) at that time is above an upper threshold, a "clear" state if delta (Δ) is below a lower threshold, and an "intermittent cloudy" state if delta (Δ) is determined to be between the upper and lower thresholds. The processor 140 may also execute instructions stored in the memory to perform other operations of the methods described herein.

Although a single infrared sensor 110 is illustrated in fig. 1, in another implementation, two or more infrared sensors may be used for redundancy in the event of one failure and/or obstruction by, for example, bird droppings or other environmental matter. In one implementation, two or more infrared sensors are used to face different orientations to capture IR radiation from different fields of view and/or at different distances from the building/structure. If two or more IR sensors are located within the housing of the infrared cloud detector 100, the IR sensors are typically offset from each other by a sufficient distance to reduce the likelihood that a shield will affect all of the IR sensors. For example, the IR sensors may be separated by at least about one inch or at least about two inches.

B. Comparison of infrared sensor temperature readings, ambient temperature readings, and delta values during a clear day and a day with afternoon clouds

As described above, the sky temperature readings obtained by the ambient temperature sensor tend to fluctuate with a smaller amplitude than the sky temperature readings obtained by the infrared radiation sensor. Infrared cloud detection according to equation 1Certain implementations of the device have logic that determines an infrared sensor temperature reading (T)_IR) And ambient temperature reading (T)_A) Delta (Δ) between to help normalize the infrared sensor temperature reading (T)_IR) Any fluctuation in the pressure. In contrast, fig. 2A-2C include temperature readings T obtained by an ambient temperature sensor of an infrared cloud detector according to one implementation_IRTemperature reading T obtained by an ambient temperature sensor of an infrared cloud detector_AAnd a plot of an embodiment of delta (Δ) between these readings. Each graph includes two curves: a plot of readings taken on a sunny day and a plot of readings taken on a day with a afternoon cloud. The infrared cloud detector used in this embodiment includes similar components to those described with respect to the infrared cloud detector 100 shown in fig. 1. In this case, the infrared cloud detector is located on the roof of the building with the infrared sensor facing vertically upwards. The infrared sensor is calibrated to measure infrared radiation in a wavelength range from about 8 μm to about 14 μm. To avoid direct sunlight from striking the infrared sensor, the infrared sensor is located behind a cover formed of a light diffusing material, such as a plastic, such as polycarbonate, polyethylene, polypropylene, and/or a thermoplastic, such as nylon or other polyamides, polyesters or other thermoplastics, among other suitable materials. In this embodiment, the infrared cloud detector further includes logic operable to calculate a temperature reading T obtained by the IR sensor_IRAnd an ambient temperature reading T obtained by an ambient temperature sensor of the infrared cloud detector_AThe difference between them delta (Δ). The logic may also be operable to determine a "cloudy" state if delta (Δ) is equal to or above an upper threshold, a "fair" state if delta (Δ) is equal to or below a lower threshold, and an "intermittent cloudy" state if delta (Δ) is between the upper and lower thresholds.

FIG. 2A illustrates two temperature readings T obtained over time by an infrared sensor of an infrared cloud detector according to this implementation_IRGraph of two curves. Two are providedEach of the curves has a temperature reading T taken by an infrared sensor over a period of a day_IR. A first curve 110 is a temperature reading T obtained by an infrared sensor during a first day with a cloud in the afternoon_IR. The second curve 112 has temperature readings T taken by the infrared sensors on a second day that is all sunny throughout the day_IR. As shown, the temperature readings T of the first curve 110 obtained during the afternoon of the first day of the cloudy afternoon_IRThe higher the temperature reading of the second curve 112, which is generally obtained during the second day of sunny weather throughout the day_IRAnd higher.

FIG. 2B illustrates an ambient temperature reading T obtained over time by an ambient temperature sensor of an infrared cloud detector discussed with respect to FIG. 2A_AGraph of two curves. Each of the two curves has a temperature reading T taken by an ambient temperature sensor over a period of a day_A. To avoid direct sunlight from striking the ambient temperature sensor, it is protected from direct sunlight. The first curve 220 has temperature readings taken by the ambient temperature sensor during the second day of the full sunny day. The second curve 222 has temperature readings taken by the infrared sensor during the second day when the entire day is clear. As shown, the ambient temperature reading T of the first curve 220 obtained during the first day with the afternoon cloud_AAt a level below the temperature reading T of the second curve 222 taken on the second day of sunny weather all day_AThe level of (c).

FIG. 2C shows the temperature reading T as discussed with respect to FIGS. 2A and 2B with the temperature reading being taken by the IR sensor_IRAnd an ambient temperature reading T obtained by an ambient temperature sensor of the infrared cloud detector_ATwo plots of calculated delta (Δ) in between. Each of the two curves has a delta (Δ) calculated over a period of one day. A first curve 230 is the calculated delta (Δ) of readings taken during the first day with the afternoon cloud. The second curve 232 is the calculated delta (Δ) obtained during the second day of sunny all day. The graph also includes an upper threshold and a lower threshold.

In fig. 2C, the value of delta (Δ) of the second curve 232 during the time interval from just before sunrise to just after sunrise and during the time interval from just sunset to just before sunset is lower than the lower threshold. Using the calculated delta (Δ) values shown in the curve in fig. 2C, the logic of the infrared cloud detector will determine the "sunny" state during this time interval. Moreover, since the value of delta (Δ) of second curve 232 is below the lower threshold at most other times of the day, the logic of the infrared cloud detector will also determine the "sunny" state at other times.

In fig. 2C, the value of delta (Δ) of the first curve 230 is above the upper threshold for most of the afternoon, and the infrared cloud detector will determine a "cloudy" condition during the afternoon. The value of delta (Δ) of the first curve 230 is below the lower threshold during the time interval just before sunrise until just after sunrise and during the time interval from just before sunset until sunset. Based on these calculated delta (Δ) values, the logic of the infrared cloud detector will determine a "sunny" state during the time interval. The value of delta (Δ) of the first curve 230 is between the lower threshold and the upper threshold during the brief period in the transition between early and late afternoons. Based on these calculated delta (Δ) values, the logic of the infrared cloud detector will determine an "intermittent cloudy day" state.

C. Infrared cloud detector system with optional photoreceptors

In certain implementations, the infrared cloud detector system includes an optional visible light photoreceptor (e.g., a photodiode) for measuring the intensity of visible radiation during operation. These systems typically include an infrared sensor, an ambient temperature sensor, a visible light sensor, and logic for determining a cloud cover condition based on readings obtained by one or more of the infrared sensor, the ambient temperature sensor, and the visible light sensor. In some cases, the infrared sensor is calibrated to measure wavelengths in the 8-14 μm spectrum. In some cases, the photoreceptor is calibrated to detect the intensity of visible light in the photopic range (e.g., between about 390nm and about 700 nm). The photoreceptor may be located in the same housing as the infrared sensor and the ambient temperature sensorOr may be separately located. In some cases, the logic is based on the temperature reading T of the infrared sensor when the confidence level of the infrared sensor is high and/or the confidence level of the photoreceptor is low_IRReading T from ambient temperature_AThe calculated delta (Δ) value in between determines the cloud cover condition. When the confidence level of the infrared sensor is low and/or the confidence level of the photoreceptor is high, the logic determines a cloud status based on the photoreceptor readings.

In various implementations, the infrared cloud detector system includes logic to use the temperature reading T from the infrared sensor when entering the time of day and the backlog_IRAmbient temperature reading T from ambient temperature sensor_ALight intensity reading from the light sensor and temperature reading T from the infrared sensor_IRTo determine the cloud condition. In some cases, the logic determines the oscillation frequency from the visible light intensity reading and/or from the temperature reading T_IRThe oscillation frequency of (2). The logic determines whether the time of day is within one of four time periods: (i) a period of time shortly before sunrise until shortly after sunrise; (ii) (ii) daytime is defined as (i) after and (iii) before; (iii) the period of time shortly before sunset (dusk) until sunset; or (iv) nighttime is defined as after (iii) and before (i). In one case, the sunrise time may be determined from measurements of the visible wavelength photoreceptor. For example, time period (i) may end at the point where the visible wavelength photoreceptor begins measuring direct sunlight, i.e., where the intensity reading of the visible light photoreceptor is at or above the minimum intensity value. Additionally or alternatively, the time period (iii) may be determined to end at a point where the intensity reading from the visible wavelength photoreceptor is at or below the minimum intensity value. In another embodiment, sunrise time and/or sunset time may be calculated using a solar calculator based on the backlog, and time periods (i) and (iii) may be calculated by a defined time period (e.g., 45 minutes) before and after the calculated sunrise/sunset time. If the time of day is within the (i) or (iii) time period, the confidence level of the photoreceptor reading tends to be low and the infrared sensor reading tends to be high. In this case, the logic isOr determining the cloud condition based on the calculated delta (Δ) without a correction factor. For example, the logic may determine a "cloudy" state if delta (Δ) is above an upper threshold, a "clear" state if delta (Δ) is below a lower threshold, and an "intermittent cloudy" state if delta (Δ) is between the upper and lower thresholds. As another example, the logic may determine a "cloudy" state if delta (Δ) is above a single threshold and may determine a "sunny" state if delta (Δ) is below the threshold. If the time of day is during (ii) the day, then the confidence level of the photoreceptor reading is at a high level and the confidence level of the infrared sensor reading tends to be low. In this case, the logic may use the photoreceptor reading to determine the cloud status as long as the calculated difference between the infrared reading and the photoreceptor reading remains at or below an acceptable value. For example, if the photoreceptor reading is above a certain intensity level, the logic may determine a "sunny" state, and if the photoreceptor reading is at or below the intensity level, the logic may determine a "cloudy" state. If the calculated difference between the infrared reading and the photoreceptor reading increases above an acceptable value, the confidence in the infrared reading increases and the logic determines the cloud cover condition based on the delta (Δ) as described above. Alternatively or additionally, if it is determined that the photoreceptor reading oscillates at a frequency greater than a first defined level, the confidence level of the infrared reading is increased, and the logic determines a cloud cover condition based on delta (Δ). If the infrared reading is determined to oscillate at a frequency greater than the second defined level, the confidence level of the photoreceptor reading is increased, and the logic determines a cloud status based on the photoreceptor reading. If the time of day is during (iv) the night, the logic may determine the cloud cover condition based on delta (Δ) as described above.

Fig. 3 depicts a schematic (side view) of an infrared cloud detector system 300 including an infrared cloud detector 310 and a photoreceptor 320 according to one implementation. Infrared cloud detector 310 includes a housing 312, an infrared sensor 314 within the outer shell of housing 312, and an ambient temperature sensor 316 also within the outer shell of housing 312. Infrared sensor 314 is configured to obtain a temperature reading T based on infrared radiation received from an area of the sky within its conical field of view 315_IR,. Ambient temperature sensor 316 is configured to obtain an ambient temperature reading T of ambient air surrounding infrared cloud detector 310_A,. In one aspect, the IR sensor is one of an infrared thermometer (e.g., thermopile), an infrared radiometer, an atmospheric radiometer, and an infrared pyrometer. In one aspect, the ambient temperature sensor is one of a thermistor, a thermometer, and a thermocouple.

The infrared cloud detector 310 is located on the roof of a building having a room 330 with a tintable window 332 (e.g., an electrochromic window having at least one electrochromic device), and the light sensor 320 is located on an exterior surface of the building. Tintable window 332 is located between the exterior and interior of a building that includes room 330. Fig. 5 also shows a table 334 in the room 330. Although in this embodiment, the light sensor 320 is located separately from the infrared cloud detector 310, in other implementations, the light sensor 320 is located in the housing of the housing or outside of the housing 312.

Infrared sensor 314 includes an imaginary axis that is perpendicular to the sensing surface of infrared sensor 314 and passes through its center. Infrared cloud detector 310 is supported by a wedge-shaped structure that orients infrared cloud detector 310 with its axis pointing at an oblique angle β from horizontal. In other implementations, other components may be used to support infrared cloud detector 310. The infrared sensor 314 is directed such that the sensing surface faces the sky and may receive infrared radiation from regions of the sky within its field of view 315. The ambient temperature sensor 130 is located within the outer shell of the housing 312 away from the edges and is shielded by the overhanging portion of the housing 312 from direct sunlight striking the sensing surface of the ambient temperature sensor 130. Although not shown, infrared cloud detector 310 also includes one or more structures that retain its components within housing 312.

As shown in fig. 3, infrared cloud detector system 300 also includes a controller 340 having a processor that can execute instructions stored in a memory (not shown) to use the logic of infrared cloud detector system 300. Controller 340 communicates (wirelessly or by wire) with infrared sensor 314 and ambient temperature sensor 316 to receive signals having temperature readings. The controller 340 is also in communication (wirelessly or wired) with the photoreceptor 320 to receive a signal having a visible light intensity reading.

In some implementations, the power/communication lines may extend from a building or another structure to the infrared cloud detector 310. In one implementation, infrared cloud detector 310 includes a network interface that may couple infrared cloud detector 310 to a suitable cable. The infrared cloud detector 310 may communicate data to the controller 340 or another controller of the building (e.g., a network controller and/or a master controller) via a network interface. In some other implementations, the infrared cloud detector 310 may additionally or alternatively include a wireless network interface capable of wireless communication with one or more external controllers.

In some implementations, the infrared cloud detector 310 or other embodiments of the infrared cloud detector may also include a battery within or coupled with its housing to power the sensors and electronic components therein. The battery may provide such power instead of or in addition to power from a power source (e.g., from a building power source). In one implementation, the infrared cloud detector further comprises at least one photovoltaic cell, for example on an outer surface of the housing. The at least one photovoltaic cell may provide power in place of or in addition to power provided by any other power source.

Infrared cloud detector system 300 also includes logic for using temperature reading T from infrared sensor 314 when entering the time of day and the product day_IRAmbient temperature reading T from ambient temperature sensor 316_AA visible light intensity reading from the photoreceptor 320, an oscillation frequency of the visible light intensity reading from the photoreceptor 320, and a temperature reading T from the infrared sensor 314_IRTo determine the cloud condition. During operation, infrared sensor 314 is basedObtaining temperature readings T from infrared radiation received from regions of the sky within its field of view 315_IRThe ambient temperature sensor 316 obtains an ambient temperature reading T of the ambient air surrounding the infrared cloud detector 310_AAnd the photoreceptor 320 obtains an intensity reading of the visible light received at its sensing surface. The processor of controller 340 receives the infrared radiation having a temperature reading T from infrared sensor 314_IRWith an ambient temperature reading T from an ambient temperature sensor 316_AAnd a signal having an intensity reading from the photoreceptor 320. The processor executes instructions stored in the memory to determine a cloud cover condition based on various inputs using logic. An embodiment of such logic is described above and also with reference to fig. 9. In one implementation, the controller 340 is also in communication with and configured to control one or more building components. For example, the controller 340 may be in communication with the tint level of the tintable window 332 and configured to control the tint level of the tintable window 332. In this implementation, the infrared cloud detector system 300 also includes logic to determine control decisions for one or more building components, such as the tintable window 332, based on the determined cloud cover conditions. An embodiment of logic for determining a control decision based on the determined cloud cover condition is described in more detail with reference to fig. 10.

While a single infrared sensor 314, ambient temperature sensor 316, and photoreceptor 320 are illustrated in fig. 3, it should be understood that the present disclosure is not so limited, and that additional components may be used in another implementation. For example, multiple components may be used for redundancy for a failure and/or a situation that is blocked or otherwise prevented from functioning. In another embodiment, two or more components may be used at different locations or in different orientations to capture different information. In one implementation, two or more infrared sensors are used to face different orientations to capture infrared radiation from different fields of view and/or different distances from a building/structure. In the case of multiple sensors, an average or mean of the values from the multiple sensors may be used to determine the cloud status. If two or more IR sensors are located within the housing of the infrared cloud detector 310, the IR sensors are typically offset from each other by a sufficient distance to reduce the likelihood that a shield will affect all of the IR sensors. For example, the IR sensors may be separated by at least about one inch or at least about two inches.

Another embodiment of an infrared cloud detector system is described below in section III with respect to fig. 11A-C.

Implementation of multiple sensors

In certain implementations, the infrared cloud detector system includes an infrared cloud detector having a visible light photoreceptor in the form of a multi-sensor device having various other optional sensors and electronic components within or on its housing. Details of various embodiments of a MULTI-SENSOR device are described in U.S. patent application 14/998,019 entitled "MULTI-SENSOR" filed on 6.10.2016, which is hereby incorporated by reference in its entirety. The multi-sensor apparatus of these implementations is configured to be located in an environment external to a building so as to expose the sensors to the external environment. In some of these implementations with multi-sensor devices, power/communication lines extend from the building to the multi-sensor devices. In one such case, the multi-sensor device includes a network interface that can couple the multi-sensor device to a suitable cable. The multi-sensor device may communicate data to a local controller, a network controller, and/or a master controller of the building via a network interface. In other implementations, the multi-sensor device may additionally or alternatively include a wireless network interface capable of wireless communication with one or more external controllers. In some implementations, the multi-sensor device can also include a battery within or coupled with its housing to power the sensors and electronic components within. The battery may provide such power instead of or in addition to power from a power source (e.g., from a building power source). In some implementations, the multi-sensor device further includes at least one photovoltaic cell, for example, on a surface of its housing.

Fig. 4A, 4B, and 4C illustrate perspective views of schematic diagrams of an infrared cloud detector system 400 including an infrared cloud detector in the form of a multi-sensor device 401 according to one such implementation. Fig. 4A and 4B illustrate that the multi-sensor device 401 includes a housing 410 coupled to a mast 420. Mast 420 may serve as a mounting assembly including a first end for coupling to base 414 of housing 410 and a second end for mounting to a building. In one embodiment, base 414 is fixedly attached or coupled to or connected with a first end of mast 420 via mechanical threads or via a compression rubber washer. Mast 420 may also include a second end, which may include a mounting or attachment mechanism for mounting or attaching mast 420 to a roof top of a building (e.g., the roof of a building having room 330 shown in fig. 3), such as a surface of the roof, a wall on the roof, or another structure on the roof. The housing includes a cover 411, and the cover 411 is formed of a light diffusion material. The cover 411 also includes a thinned portion 412.

Fig. 4B also shows that infrared cloud detector system 400 includes an ambient temperature sensor 420, where ambient temperature sensor 420 is located on a bottom surface of base 414 of multi-sensor device 401. The ambient temperature sensor 420 is configured to measure an ambient temperature of the external environment during operation. When the infrared cloud detector system 400 is located in an outdoor environment with the top surface facing upward, the ambient temperature sensor 420 is located on the bottom surface to block direct solar radiation. The temperature sensor 420 may be, for example, a thermistor, a thermocouple, a resistance thermometer, a silicon bandgap temperature sensor, and the like.

Fig. 4C illustrates a perspective view of some of the internal components of the multi-sensor device 401 of the infrared cloud detector system 400 shown in fig. 4A and 4B. As shown, the infrared cloud detector system 400 also includes a visible light sensor 440, a first infrared sensor 452, and a second infrared sensor 454. The first infrared sensor 452 and the second infrared sensor 454 are located at an upper portion of the multi-sensor device 401, and are located behind the cover 411 (shown in fig. 4A and 4B) formed of a light diffusion material.

As shown in fig. 4C, the first infrared sensor 452 has a first orientation axis 453 perpendicular to its sensing surface. The second infrared sensor 454 has a second orientation axis 455 that is perpendicular to its sensing surface. In the illustrated embodiment, first infrared sensor 452 and second infrared sensor 454 are positioned such that their orientation axes 453, 455 face outward from a top portion of housing 410 (shown in fig. 4A and 4B) so as to enable temperature readings to be obtained during operation that are based on infrared radiation captured from above multi-sensor device 401. First infrared sensor 452 is separated from second infrared sensor 454 by at least about one inch. During operation, the first infrared sensor 452 and the second infrared sensor 454 detect infrared radiation that radiates from any object or medium within their field of view. The field of view is based on the physical and material properties of first infrared sensor 452 and second infrared sensor 454. Some embodiments of infrared sensors have a field of view ranging from about 50 degrees to about 80 degrees based solely on their physical and material properties. In one particular embodiment, the infrared sensor has a field of view of about 70.

The photoreceptor 440 has an orientation axis 442 perpendicular to its sensing surface. The photoreceptor 440 is located behind the thinned portion 412 of the housing 410 as shown in FIG. 4A. Thinned portion 412 allows photoreceptor 440 to receive visible radiation through thinned portion 412. During operation, photoreceptor 440 measures the intensity of visible light received through thinned portion 412.

In one implementation, infrared cloud detector system 400 also includes an external controller having a processor that may execute instructions stored in a memory (not shown) to use the logic of infrared cloud detector system 400. In this implementation, the infrared cloud detector system 400 also includes logic to use the temperature reading T from one of the two infrared sensors 452, 454 when entering the time of day and the backlog_IRAmbient temperature reading T from ambient temperature sensor 420_ALight intensity readings from the photoreceptor 440, oscillation frequency of visible light intensity readings from the photoreceptor 440, and from an infrared sensorTemperature readings T of 452, 454_IRTo determine the cloud state. Embodiments of such logic are described herein, for example, with respect to fig. 8-10.

The external controller communicates (wirelessly or by wire) with the infrared sensors 452, 454 and the ambient temperature sensor 420 to receive signals having temperature readings. The controller also communicates (wirelessly or wired) with the photoreceptor 440 to receive a signal having a visible light intensity reading. In some implementations, the power/communication lines may extend from a building or another structure to the infrared cloud detector system 400. In one implementation, the infrared cloud detector system 400 includes a network interface that may be coupled to a suitable cable. The infrared cloud detector system 400 may communicate data to an external controller of the building or another controller through a network interface. In some other implementations, the infrared cloud detector system 400 can additionally or alternatively include a wireless network interface capable of wireless communication with one or more external controllers. In some implementations, the infrared cloud detector system 400 can also include a battery within or coupled with the housing to power the sensors and the electronic components therein. The battery may provide such power instead of or in addition to power from a power source (e.g., from a building power source). In some implementations, the infrared cloud detector system 400 also includes at least one photovoltaic cell, for example, on a surface of the housing.

D. Comparing intensity readings of a photoreceptor to delta values under different cloud conditions

As described above, the infrared sensor may be more accurate than the visible light sensor in detecting the "clear" state in the early morning and evening. However, direct sunlight and other conditions can cause some noise that causes the infrared sensor readings to oscillate. If the frequency of these oscillations is low, the infrared sensor readings can be used to make a high confidence assessment of the cloud status. Also, certain conditions (e.g., fast moving clouds) may cause oscillations in the photoreceptor readings. If the oscillation frequency is low, a photoreceptor can be used for readingThe method is used for evaluating the high confidence level of the cloud cover condition in the daytime. In some implementations, the logic can determine whether the oscillations of the infrared sensor reading have a high frequency and/or the oscillations of the photoreceptor reading have a high frequency. If it is determined that the oscillation of the infrared sensor reading has a high frequency, the logic uses the photoreceptor reading to determine the cloud status. If it is determined that the oscillation of the photoreceptor reading has a high frequency, the logic uses the difference between the infrared sensor reading and the ambient temperature sensor reading to determine the cloud status. To illustrate the technical advantage of this logic of selecting the type of sensor reading to use in accordance with oscillation, fig. 5A, 5B, 6A, 6B, 7A, and 7B include graphs of plots of intensity readings I obtained by a visible light photoreceptor for comparison to temperature readings T obtained by an infrared sensor under different cloud conditions_IRWith temperature readings T obtained by ambient temperature sensors_AThe difference delta (Δ) therebetween is compared. The visible light photoreceptor, infrared sensor, and ambient temperature sensor are similar to those described with respect to the components of infrared cloud detector 310 shown in fig. 3. Each curve has readings taken over a period of one day.

Fig. 5A-5B include graphs of readings taken during a day, both clear and clear throughout the day, except during the middle of the day through the cloud. Fig. 5A is a graph of a curve with a curve 510 of intensity readings I taken over time by a visible light photoreceptor. FIG. 5B is a graph having temperature readings T taken over time by an infrared sensor_IRWith temperature readings T taken over time by ambient temperature sensors_AA plot of the curve 520 for the difference delta (Δ) therebetween. As shown in curve 510 of fig. 5A, the intensity reading I obtained by the visible light photoreceptor is high for most of the day and falls off as the high frequency (short period) oscillates as the cloud passes through at noon in the day. Curve 520 of fig. 5A shows that the value of delta (Δ) does not increase above the lower threshold throughout the day, which represents a high confidence "sunny" state.

6A-6B include graphs of plots of readings taken during the day, with frequent passing clouds in the morning until the afternoon, andthere are two slow moving clouds passing later in the day. Fig. 6A is a graph of a curve 610 with intensity readings I taken over time by a visible light photoreceptor. FIG. 6B is a graph having temperature readings T taken by an infrared sensor over time_IRWith temperature readings T taken over time by ambient temperature sensors_AA plot of curve 640 for the difference delta (Δ) therebetween. As shown in the curve 610 of fig. 6A, the intensity reading I obtained by the visible light photoreceptor has a high frequency portion 620 during the time period in the morning until afternoon when clouds frequently pass. When two slow moving clouds pass, the curve 610 has a low frequency portion 630 later in the afternoon. Curve 640 in fig. 6B shows that the value of delta (Δ) has a high frequency during the time period that clouds frequently pass in the morning until afternoon, and remains between the upper and lower thresholds indicating intermittent cloudy days. The delta (Δ) value at late afternoon has a low frequency oscillation with a value between the upper and lower thresholds and also below the lower threshold for transitioning between the "intermittent cloudy" and "sunny" states. In this case, the infrared sensor value represents a high-confidence "intermittent cloudy" state from morning to afternoon, and the photoreceptor value represents a high-confidence "intermittent cloudy" state at a later time in the afternoon.

Fig. 7A-7B include graphs of plots of readings taken over time during a day that is cloudy except for short times during the noon of the day. Fig. 7A is a graph of a curve 710 with intensity readings I taken over time by a visible light photoreceptor. FIG. 7B is a graph having temperature readings T taken by an infrared sensor over time_IRTemperature reading T obtained over time with an ambient temperature sensor_AA plot of the plot 720 of the difference delta (Δ) therebetween. As is evident from the curve 710 of fig. 7A, the intensity reading I obtained by the visible light photoreceptor is low for most of the day and increases with high frequency (short period) oscillations when the sky is briefly clear during the midday of the day. Curve 720 of FIG. 7A shows that the value of delta (Δ) is not below the upper threshold throughout the day, which represents a high confidence "cloudy" stateState.

In some implementations, the infrared cloud detector system uses readings from an infrared sensor that measures wavelengths in the infrared range, such as wavelengths between 8-14 microns, to estimate the difference Δ between the ambient temperature and the temperature readings of the measuring infrared sensor. In some cases, one or more correction factors are applied to the calculated difference Δ. The difference Δ provides a relative sky temperature value that may be used to classify the cloud cover condition. For example, the cloudiness condition may be determined in one of three situations, "sunny", "cloudy", and "cloudy". When using the infrared cloud detector system, the determined cloud cover condition is independent of whether the sun is present or whether it is before sunrise/sunset.

An infrared cloud detector system according to certain implementations may have one or more technical advantages. For example, in early morning and evening conditions, the infrared sensor may determine whether it is a cloudy or sunny day, regardless of the visible light intensity level. The determination of this cloud status during these times may provide an additional background to determine the tint state of the tintable window when the photoreceptor is inactive while the sun is still rising. As another example, an infrared sensor may be used to detect general cloud cover conditions within its field of view. This information may be used in conjunction with the photoreceptor readings to determine whether a "sunny" state or a "cloudy" state as determined by the photoreceptor is likely to persist. For example, if the photoreceptor detects a sharp rise in intensity level (which tends to indicate a "sunny" state), but the infrared sensor indicates a "cloudy" state, it is expected that the "sunny" state will not persist. Conversely, if the infrared sensor shows a "clear" state and the photoreceptor reading indicates that it is in a "clear" state, then the "clear" state may persist. As another example, where the tintable window needs to be in a steady state at sunrise, the transition needs to begin at X times before sunrise (e.g., the transition time). During this time, the photoreceptor is inactive because the illumination is minimal. The IR sensor may determine the cloud cover condition before sunrise to inform the control logic whether to start the tinting process (in clear sky) or to keep the tintable window bright in an expected "cloudy" state at sunrise.

Method for determining cloud cover conditions using readings from at least one infrared sensor and one ambient temperature sensor

Fig. 8-10 show flow diagrams describing methods of determining a cloud condition using readings from at least one infrared sensor and one ambient temperature sensor, according to various embodiments. In fig. 9-10, readings from at least one photoreceptor may also be used to determine cloud conditions under certain conditions. In some cases, the infrared sensor used to obtain the temperature readings is calibrated to detect infrared radiation in the approximately 8 μm to 14 μm spectrum and/or has a field of view of approximately 72 degrees. In some cases, the photoreceptor used to obtain the photoreceptor reading is calibrated to detect the intensity of visible light within a photopic range (e.g., between about 390nm and about 700 nm), which is typically referred to under lighting conditions (e.g., at a brightness level of about 10 cd/m)²To about 108cd/m²In between) light that is visible to the normal human eye. While the methods are described with respect to readings from a single infrared sensor, a single ambient temperature sensor, and/or a single photosensor, it should be understood that values from multiple sensors of the type may be used, e.g., multiple sensors oriented in different directions may be used. If multiple sensors are used, the method may use a single value for a sensor based on a particular orientation (e.g., a functional sensor), or obtain an average, mean, or other statistically relevant value of readings from multiple functional sensors. In other cases, there may be redundant sensors and the infrared cloud detector may have logic that uses values from the functional sensors. For example, by evaluating which sensors are operating and/or which sensors are not functioning based on comparing readings from various sensors.

A. Method I

Fig. 8 shows a flow chart 800 describing a method of determining a cloud cover condition using temperature readings from an infrared sensor and an ambient temperature sensor according to an implementation. The infrared sensor and the ambient temperature sensor of the infrared cloud detector system typically take readings (at sample times) periodically. The processor executes instructions stored in the memory to perform the operations of the method. In one implementation, the infrared cloud detector system has components similar to those described with respect to the system having the infrared cloud detector 100 described with respect to fig. 1. In another implementation, the infrared cloud detector system has components similar to those described with respect to the system having infrared cloud detector 310 in fig. 3.

As shown in fig. 8, the method begins at operation 801. At operation 810, a temperature reading T is received at a processor with temperature readings obtained by an infrared sensor_IRAnd a temperature reading T obtained by an ambient temperature sensor_AOf the signal of (1). Signals from the infrared sensor and/or the ambient temperature sensor are received wirelessly and/or via a wired electrical connection. The infrared sensor obtains a temperature reading from infrared radiation received within its field of view. The infrared sensors are typically oriented toward an area of the sky of interest, such as an area above a building. The ambient temperature sensor is configured to be exposed to an external environment to measure an ambient temperature.

At operation 820, the processor calculates a temperature reading T obtained by the infrared sensor_IRWith the temperature reading T obtained by the ambient temperature sensor at the sampling time_AThe difference between delta (Δ). Optionally (represented by the dashed line), a correction factor is applied to the calculated delta (Δ) (operation 830). Some examples of correction factors that may be applied include humidity, sun angle/solar altitude angle, and field altitude.

At operation 840, the processor determines whether the calculated delta (Δ) value is below a lower threshold (e.g., -5 degrees celsius, -2 degrees celsius, etc.). If it is determined that the calculated delta (Δ) value is below the lower threshold, the cloudiness condition is determined to be a "clear" state (operation 850). During operation of the infrared cloud detector, the method then increments to the next sample time and returns to operation 810.

If it is determined that the calculated delta (Δ) is above the lower threshold, the processor determines whether the calculated delta (Δ) is above an upper threshold (e.g., 0 degrees Celsius, 2 degrees Celsius, etc.) at operation 860. If it is determined that the calculated delta (Δ) is above the upper threshold at operation 860, the processor determines the cloudiness condition as a "cloudy" state (operation 870). During operation of the infrared cloud detector, the method then increments to the next sampling time and returns to operation 810.

If it is determined that the delta (Δ) calculated at operation 860 is below the upper threshold, the processor determines the cloudiness condition as "intermittent cloudy day" or another intermediate state (operation 880). During operation of the infrared cloud detector, the method then increments to the next sample time and returns to operation 810.

B. Method II

Fig. 9 shows a flow chart 900 describing a method of determining a cloud volume condition using readings from an infrared sensor, an ambient temperature sensor, and a photoreceptor of an infrared cloud detector system according to an implementation. The infrared sensor, ambient temperature sensor, and photosensor typically obtain readings periodically (at sample time). The infrared cloud detector system also includes a processor that can execute instructions stored in the memory to perform the operations of the method. In one implementation, the infrared sensor, ambient temperature sensor, and photosensor are similar to the components of the infrared cloud detector system 300 described with respect to fig. 3. In another implementation, the infrared sensor, the ambient temperature sensor, and the photosensor are similar to the components of the infrared cloud detector system 400 described with respect to fig. 4A-4C.

In fig. 9, the method begins at operation 901. At operation 910, one or more signals having a temperature reading T obtained by an infrared sensor at a particular sampling time are received at a processor_IRFrom temperature readings T obtained at the sampling time by an ambient temperature sensor_AAnd the intensity readings taken by the photoreceptor at the sampling time. Signals from the infrared sensor, ambient temperature sensor, and photosensor are received wirelessly and/or via a wired electrical connection. The infrared sensor obtains a temperature reading from infrared radiation received within its field of view. The infrared sensors are typically oriented toward an area of the sky of interest, such as an area above a building. Ambient temperatureThe sensor is configured to be exposed to an external environment to measure an ambient temperature. The sensing surface of the photoreceptor is also generally directed towards the region of the sky of interest, and direct sunlight is blocked or diffused from illuminating the sensing surface.

At operation 920, the processor determines whether the time of day is during one of the following time periods: (i) a period beginning shortly before sunrise (e.g., beginning at a first time 45 minutes before sunrise, 30 minutes before sunrise, 20 minutes before sunrise, or other suitable period before sunrise) until slightly after sunrise (e.g., beginning at a second time 45 minutes after sunrise, 30 minutes after sunrise, 20 minutes after sunrise, or other suitable period) and (iii) a period beginning shortly before sunset (dusk) (e.g., beginning at a third time 45 minutes before sunset, 30 minutes before sunset, 20 minutes before sunset, or other suitable period before sunset) until sunset. In one case, the sunrise time may be determined from measurements of the visible wavelength photoreceptor. For example, time period (i) may end at the point where the visible wavelength photoreceptor begins measuring direct sunlight, i.e., where the intensity reading of the visible light photoreceptor is at or above the minimum intensity value. Additionally or alternatively, the time period (iii) may be determined to end at a point where the intensity reading from the visible wavelength photoreceptor is at or below the minimum intensity value. In another embodiment, sunrise and/or sunset times may be calculated using a solar calculator, and the backlogs and time periods (i) and (iii) may be calculated by a defined time period (e.g., 45 minutes) before and after the calculated sunrise/sunset time.

If it is determined at operation 920 that the time of day is during any of time periods (i) or (iii), the processor calculates a temperature reading T obtained by the infrared sensor_IRWith the temperature reading T obtained by the ambient temperature sensor at the sampling time (operation 930)_AThe difference between delta (Δ). Optionally (represented by the dashed line), a correction factor is applied to the calculated delta (Δ) (operation 930). Some examples of correction factors that may be applied include humidity, sun angle/solar altitude angle, and field altitude.

In one embodiment, the processor also determines whether the infrared readings oscillate at a frequency greater than a second defined level at operation 920. If the processor determines at operation 920 that the time of day is within time period (i) or (iii) and the infrared readings oscillate at a frequency greater than a second defined level, the processor applies operation 990 to determine the cloud status using the photoreceptor readings. For example, if the photoreceptor reading is above some minimum intensity level, the processor may determine a "sunny" state, and if the photoreceptor reading is at or below the minimum intensity level, the processor may determine a "cloudy" state. If the system is still running, the method increments to the next sample time and returns to operation 910.

At operation 934, the processor determines whether the calculated delta (Δ) value is below a lower threshold (e.g., -5 degrees Celsius, -2 degrees Celsius, etc.). If it is determined that the calculated delta (Δ) value is below the lower threshold, the cloudiness condition is determined to be a "clear" state (operation 936). During operation of the infrared cloud detector, the method then increments to the next sample time and returns to operation 910.

If it is determined that the calculated delta (Δ) is above the lower threshold, the processor determines whether the calculated delta (Δ) is above an upper threshold (e.g., 0 degrees Celsius, 2 degrees Celsius, etc.) at operation 940. If it is determined that the delta (Δ) calculated at operation 940 is above the upper threshold, the processor determines that the cloudiness condition is a "cloudy" state (operation 942). If still in operation, the method increments to the next sample time and returns to operation 910.

If it is determined that the delta (Δ) calculated at operation 940 is below the upper threshold, the processor determines the cloud cover condition as "intermittent cloudy day" or another intermediate state (operation 950). If the system is still running, the method increments to the next sample time and returns to operation 910.

If it is determined that the time of day is not during either of time periods (i) or (iii) at operation 920, the processor determines whether the time of day is during time period (ii), which is the day after time period (i) and before time period (iii) (operation 960). If the processor determines at operation 960 that the time of day is at timeDuring the day of segment (ii), the processor then calculates the temperature reading T obtained by the infrared sensor_IRAnd the intensity reading obtained by the photoreceptor (operation 970). At operation 980, the processor determines whether the calculated difference is within acceptable limits. If the processor determines that the calculated difference is greater than the acceptable limit at operation 980, the processor applies operation 930 to calculate a delta (Δ) and uses the calculated delta (Δ) to determine the cloud cover condition as discussed above.

In one embodiment, the processor also determines whether the infrared readings oscillate at a frequency greater than a second defined level at operation 960. If the processor determines that the time of day is within the time period (ii) and the infrared readings oscillate at a frequency greater than a second defined level at operation 960, the processor applies operation 990 to determine the cloud status using the photoreceptor readings. For example, if the photoreceptor reading is above some minimum intensity level, the processor may determine a "sunny" state, and if the photoreceptor reading is at or below the minimum intensity level, the processor may determine a "cloudy" state. If the system is still running, the method increments to the next sample time and returns to operation 910.

If the processor determines at operation 980 that the calculated difference is within acceptable limits, the photoreceptor readings are used to determine a cloud cover condition (operation 990). For example, if the photoreceptor reading is above some minimum intensity level, the processor may determine a "sunny" state, and if the photoreceptor reading is at or below the minimum intensity level, the processor may determine a "cloudy" state. If the system is still running, the method increments to the next sample time and returns to operation 910.

In one embodiment, the processor also determines at operation 970 whether the photoreceptor reading oscillates at a frequency greater than a first defined level and whether the infrared reading oscillates at a frequency greater than a second defined level. If the processor determines at operation 980 that the calculated difference is within acceptable limits and the processor determines that the photoreceptor reading is oscillating at a frequency greater than a first defined level, the processor applies operation 930 to calculate delta (Δ) and uses the calculated delta (Δ) for determining the cloud condition as described above. If the processor determines at operation 980 that the calculated difference is not within acceptable limits and the processor determines that the infrared readings are oscillating at a frequency greater than a second defined level, the processor applies operation 990 to determine a cloud status using the photoreceptor readings. For example, if the photoreceptor reading is above some minimum intensity level, the processor may determine a "sunny" state, and if the photoreceptor reading is at or below the minimum intensity level, the processor may determine a "cloudy" state. If the system is still running, the method increments to the next sample time and returns to operation 910.

If the processor determines at operation 960 that the time of day is in the night time period (iv) after time period (iii) and before time period (i), the processor calculates delta at operation 930 and determines the cloud cover condition as described above using the calculated delta (delta).

C. Method III-module C algorithm using infrared sensor, ambient temperature sensor and photosensor readings.

In energy efficient buildings, the control logic for setting the level of its building systems may take into account cloud cover. For example, in a building with optically switchable windows, the control logic may take into account the amount of cloudiness in setting the window optical state (e.g., the tint state in an electrochromic window). The conventional systems purporting to provide such functionality typically employ expensive sensing devices to map the entire sky and orbit cloud. The mapping technique may also be hindered by not being able to register clouds until there is enough light to see them. Thus, by the time the cloud is registered, the building system may not need to be adjusted.

In various implementations described herein, the cloud volume condition (e.g., the described system in fig. 1, system 300 in fig. 3, system 400 in fig. 4A-4C, or other infrared cloud detector systems described herein) determined from the infrared cloud detector system by the sensor data may be used to set the level of the building system. As an embodiment, this section describes control logic that uses sensor readings from sensors in an infrared cloud detector system to determine a cloud cover condition and sets a tint level in one or more optically switchable windows (e.g., electrochromic windows) of a building based on the determined cloud cover condition. The ELECTROCHROMIC window has one or more ELECTROCHROMIC DEVICES, such as described in U.S. patent 8,764,950 entitled "ELECTROCHROMIC DEVICES" issued 7/1/2014 and U.S. patent application 13/462,725 entitled "ELECTROCHROMIC DEVICES" filed 5/2/2012, both of which are incorporated herein by reference in their entirety.

i) Introduction to electrochromic devices/windows

Fig. 10A schematically depicts an electrochromic device 1000 in cross-section. Electrochromic device 1000 includes a substrate 1002, a first Conductive Layer (CL)1004, an electrochromic layer (EC)1006, an ion conductive layer (IC)1008, a counter electrode layer (CE)1010, and a second Conductive Layer (CL) 1014. In one implementation, the electrochromic layer (EC)1006 and the counter electrode layer (CE)1010 comprising tungsten oxide comprise nickel-tungsten oxide.

Layers

1004, 1006, 1008, 1010, and 1014 are collectively referred to as an electrochromic stack 1020. A voltage source 1016 operable to apply a potential across the electrochromic stack 1020 affects a transition of the electrochromic device, for example, a transition between a bleached state (e.g., as described in fig. 10B) and a colored state (e.g., as described in fig. 10C). The order of the layers may be reversed relative to the substrate 1002.

In some cases, electrochromic devices having different layers may be fabricated as all solid state devices and/or all inorganic devices. Embodiments of such Devices and methods of making the same are described in more detail in U.S. patent application No. 12/645,111 entitled "Fabrication of Low-defect electrochemical Devices" filed on 12/22 of 2009 and U.S. patent application No. 12/645,159 entitled "electrochemical Devices" and filed on 12/22 of 2009 (issued as U.S. patent 8,432,603 on 4/30 of 2013), both of which are incorporated herein by reference in their entirety. However, it should be understood that any one or more layers in the stack may contain a certain amount of organic material. This can also be said for liquids that may be present in small amounts in one or more layers. It should also be understood that the solid material may be deposited or otherwise formed by processes employing liquid components, such as certain processes employing sol-gel or chemical vapor deposition. Additionally, it should be understood that reference to a transition between the bleached state and the colored state is non-limiting and suggests only one example of many of the electrochromic transitions that may be implemented. Unless otherwise indicated herein (including the foregoing discussion), whenever reference is made to a bleached-colored transition, the corresponding device or process includes other optical state transitions, such as non-reflective to reflective, transparent to opaque, and the like. Furthermore, the term "bleached" refers to an optically neutral state, such as colorless, transparent, or translucent. Still further, unless otherwise specified herein, the "color" of the electrochromic transition is not limited to any particular wavelength or range of wavelengths. As will be appreciated by those skilled in the art, the selection of suitable electrochromic and counter electrode materials determines the relevant optical transition.

In some implementations, the electrochromic device is configured to reversibly cycle between a bleached state and a colored state. In some cases, when the electrochromic device is in a bleached state, a potential is applied to the electrochromic stack 1020 such that the available ions in the stack are primarily located in the counter electrode 1010. When the potential on the electrochromic stack is reversed, ions are transported across the ion conducting layer 1008 to the electrochromic material 1006 and transition the material to the colored state. In a similar manner, the electrochromic devices of certain implementations described herein are configured to reversibly cycle between different tint levels (e.g., a bleached state, a darkest state, and an intermediate level between the bleached state and the darkest state).

Referring again to fig. 10A, the voltage source 1016 is configured to operate with input from the sensor. The voltage source 1016 interfaces with a device controller (not shown in this figure) as described herein. In addition, the voltage source 1016 may interface with an energy management system that controls the electrochromic device according to various criteria such as time of year, time of day, and measured environmental conditions. Such an energy management system in combination with a large area electrochromic device can significantly reduce energy consumption of a building having electrochromic windows.

Any material having suitable optical, electrical, thermal, and mechanical properties may be used as substrate 1002 or other substrate of the electrochromic stack described herein. Examples of suitable substrates include, for example, glass, plastic, and mirror materials. Suitable glasses include clear or tinted soda lime glass, including soda lime float glass. The glass may be tempered or untempered. In many cases, the substrate is a glass pane sized for residential fenestration applications. The dimensions of such panes of glass can vary widely depending on the particular needs of the dwelling. In other cases, the substrate is architectural glass. Architectural glass is commonly used in commercial buildings, but may also be used in residential buildings, and typically, but not necessarily, separates the indoor environment from the outdoor environment. In certain embodiments, the architectural glass is at least 20 inches by 20 inches, and may be larger, for example up to about 80 inches by 120 inches. Architectural glass is typically at least about 2mm thick, typically between about 3mm and about 6mm thick. Of course, electrochromic devices may be scaled relative to smaller or larger substrates than architectural glass. Further, the electrochromic device may be disposed on any size and shape of mirror.

On top of the illustrated substrate 1002 is a conductive layer 1004. In certain implementations, one or both of

conductive layers

1004 and 1014 are inorganic and/or solid.

Conductive layers

1004 and 1014 can be made of many different materials, including conductive oxides, thin metal coatings, conductive metal nitrides, and composite conductors. Typically,

conductive layers

1004 and 1014 are transparent at least in the wavelength range in which the electrochromic layer exhibits electrochromism. The transparent conductive oxide comprises a metal oxide and a metal oxide doped with one or more metals. Examples of such metal oxides and doped metal oxides include indium oxide, indium tin oxide, doped indium oxide, tin oxide, doped tin oxide, zinc aluminum oxide, doped zinc oxide, ruthenium oxide, doped ruthenium oxide, and the like. Since oxides are commonly used for these layers, they are sometimes referred to as "transparent conductive oxide" (TCO) layers. Substantially transparent thin metal coatings, and combinations of TCOs and metal coatings may also be used.

The function of the conductive layers is to spread the potential provided by the voltage source 1016 across the surface of the electrochromic stack 1020 to the interior regions of the stack with a relatively small ohmic potential drop. The potential is transferred to the conductive layer through an electrical connection with the conductive layer. In some aspects, at least one bus bar in contact with conductive layer 1004 and at least one bus bar in contact with conductive layer 1014 provides an electrical connection between voltage source 1016 and

conductive layers

1004 and 1014.

Conductive layers

1004 and 1014 can also be connected to voltage source 1016 by other conventional methods.

Overlying the illustrated conductive layer 1004 is an electrochromic layer 1006. In some aspects, the electrochromic layer 1006 is inorganic and/or solid. The electrochromic layer may comprise any one or more of a number of different electrochromic materials, including metal oxides. Some examples of suitable metal oxides include tungsten oxide (WO)₃) Molybdenum oxide (MoO)₃) Niobium oxide (Nb)₂O₅) Titanium oxide (TiO)₂) Copper oxide (CuO), iridium oxide (Ir)₂O₃) Chromium oxide (Cr)₂O₃) Manganese oxide (Mn)₂O₃) Vanadium oxide (V)₂O₅) Nickel oxide (Ni)₂O₃) Cobalt oxide (Co)₂O₃) And the like. During operation, the electrochromic layer 1006 transfers ions to the counter electrode layer 1010 and receives ions from the counter electrode layer 1010 to cause a reversible optical transition. Typically, the coloration (or any change in optical properties-e.g., absorbance, reflectance, and transmittance) of an electrochromic material is caused by reversible ion insertion (e.g., intercalation) into the material and corresponding charge-balanced electron injection. Typically, a portion of the ions responsible for the optical transition are irreversibly bound in the electrochromic material. Some or all of the irreversibly bound ions are used to compensate for "blind charges" in the material. In most electrochromic materials, suitable ions include lithium ions (Li)⁺) And hydrogen ion (H)⁺) (i.e., protons). However, in some cases, other ions will be suitable. In various embodiments, lithium ions are used to create the electrochromic phenomenon. Lithium ion intercalating tungsten oxide (WO)_3-y(0<y is less than or equal to 0.3)) to change the tungsten oxide from transparent (bleached state) to blue (colored state).

Referring again to fig. 10A, in electrochromic stack 1020, ion conducting layer 1008 is sandwiched between electrochromic layer 1006 and counter electrode layer 1010. In some embodiments, the counter electrode layer 1010 is inorganic and/or solid. The counter electrode layer may comprise one or more of a variety of different materials that serve as ion reservoirs when the electrochromic device is in a bleached state. During the electrochromic transition, which is initiated by, for example, applying an appropriate potential, the counter electrode layer transfers some or all of the ions it holds to the electrochromic layer, changing the electrochromic layer to a colored state. Meanwhile, in the case of NiWO, the counter electrode layer is colored with loss of ions. In some embodiments, for use in conjunction with WO₃Suitable materials for the complementary counter electrode include nickel oxide (NiO), nickel tungsten oxide (NiWO), nickel vanadium oxide, nickel chromium oxide, nickel aluminum oxide, nickel manganese oxide, nickel magnesium oxide, chromium oxide (Cr)₂O₃) Manganese oxide (MnO)₂) And prussian blue. When charge is removed from the counter electrode 1010 made of nickel tungsten oxide (i.e., ions are transported from the counter electrode 1010 to the electrochromic layer 1006), the counter electrode layer 1010 will transition from the transparent state to the colored state.

In the illustrated electrochromic device 1100, an ion conductive layer 1008 is present between the electrochromic layer 1006 and the counter electrode layer 1010. The ionically conductive layer 1008 serves as a medium through which ions (in the form of an electrolyte) are transported when the electrochromic device transitions between the bleached state and the colored state. Preferably, the ionically conductive layer 1008 has a high conductivity for the relevant ions of the electrochromic layer and the counter electrode layer, but a sufficiently low electronic conductivity such that negligible electron transfer occurs during normal operation. Thin ion-conducting layers with high ionic conductivity allow for fast ionic conduction and thus fast switching for achieving high performance electrochromic devices. In certain aspects, the ionically conductive layer 1008 is inorganic and/or solid.

Examples of suitable ion-conducting layers for the ion-conducting layer (i.e. for electrochromic devices with different IC layers) include silicates, silicon oxide, tungsten oxide, tantalum oxide, niobium oxide and borates. These materials may be doped with different dopants, including lithium. The lithium doped silica comprises lithium silicon-aluminum-oxide. In some embodiments, the ion-conducting layer comprises a silicate-based structure. In some embodiments, silicon-aluminum-oxide (SiAlO) is used for the ion conductive layer 1008.

In certain implementations, electrochromic device 1000 may include one or more additional layers (not shown), such as one or more passive layers. Passive layers for improving certain optical properties may be included in electrochromic device 1000. Passive layers for providing moisture or scratch resistance may also be included in the electrochromic device 1000. For example, the conductive layer may be treated with an antireflective or protective oxide or nitride layer. Other passive layers may be used to hermetically seal the electrochromic device 300.

Fig. 10B is a schematic cross-section of an electrochromic device in a bleached state (or transitioning to a bleached state). According to the illustrated embodiment, the electrochromic device 1100 includes a tungsten oxide electrochromic layer (EC)1106 and a nickel-tungsten oxide counter electrode layer (CE) 1110. Electrochromic device 1100 also includes substrate 1102, Conductive Layer (CL)11011, ion conductive layer (IC)1108, and Conductive Layer (CL) 1114.

Layers

1104, 1106, 1108, 1010, and 1114 are collectively referred to as an electrochromic stack 1120. The power supply 1116 is configured to apply a voltage potential and/or current to the electrochromic stack 1120 through suitable electrical connections (e.g., bus bars) to the

conductive layers

1104 and 1114. In one aspect, the voltage source is configured to apply a potential of about a few volts in order to drive a transition of the device from one optical state to another. The polarity of the potential as shown in fig. 10B is such that ions (lithium ions in this embodiment) are primarily present in the nickel-tungsten oxide counter electrode layer 1110 (as indicated by the dashed arrows).

Fig. 10C is a schematic cross-section of the electrochromic device 1100 shown in fig. 10B but in a colored state (or transitioning to a colored state). In fig. 10C, the polarity of the voltage source 1116 is reversed, making the electrochromic layer 1106 more negative to accept additional lithium ions to transition to the colored state. As indicated by the dashed arrows, lithium ions are transported across the ionically conductive layer 1108 to the tungsten oxide electrochromic layer 1106. The tungsten oxide electrochromic layer 1106 is shown in a colored state or transitioning to a colored state. The nickel-tungsten oxide counter electrode 1110 is also shown in a colored state or transitioning to a colored state. As explained, nickel-tungsten oxide gradually becomes more opaque as it gives up (deintercalates) lithium ions. In this embodiment, there is a synergistic effect in that the transition to the colored state of both

layers

1106 and 1110 helps to reduce the amount of light transmitted through the electrochromic stack and the substrate.

In certain implementations, an electrochromic device may include an Electrochromic (EC) electrode layer and a Counter Electrode (CE) layer separated by an ion-conducting (IC) layer having high conductivity to ions and high resistance to electrons. The ion conducting layer thus prevents a short circuit between the electrochromic layer and the counter electrode layer, as is conventionally understood. The ion-conducting layer allows the electrochromic electrode and the counter electrode to retain an electric charge, thereby maintaining their bleached or colored state. In electrochromic devices having different layers, the components form a stack comprising an ion conducting layer sandwiched between an electrochromic electrode layer and a counter electrode layer. The boundaries between these three stack components are defined by abrupt changes in composition and/or microstructure. Thus, these devices have three distinct layers with two abrupt interfaces.

According to certain implementations, the counter electrode and the electrochromic electrode are formed in close proximity to each other, sometimes in direct contact, without separately depositing the ion-conducting layer. In some implementations, electrochromic devices having an interface region rather than a different IC layer are used. These Devices and methods of making them are described in U.S. patent No. 8,300,298, U.S. patent No. 8,582,193, U.S. patent No. 8,764,950, U.S. patent No. 8,764,95, each entitled "electrochemical Devices," and each of which is incorporated by reference herein in its entirety.

In certain implementations, the electrochromic device may be integrated into an Insulated Glass Unit (IGU) of the electrochromic window, or may be in a single-pane electrochromic window. For example, an electrochromic window may have an IGU that includes a first electrochromic tool and a second tool. The IGU also includes a spacer separating the first electrochromic tool and the second tool. The second tool in the IGU may be a non-electrochromic tool or other tool. For example, the second tool may have an electrochromic device and/or one or more coatings thereon, such as a low E coating or the like. Any of the tools may be laminated glass. Between the spacer and the first TCO layer of the electrochromic lite is a primary sealing material. The primary sealing material is also located between the spacer and the second glass tool. Around the periphery of the spacer is a secondary seal. These seals help to keep moisture out of the interior space of the IGU. They also serve to prevent argon or other gases directed into the interior space of the IGU from escaping. The IGU also includes a bus bar for connection to a window controller. In some implementations, one or both of the bus bars are internal to the completed IGU, however in one implementation, one bus bar is external to the seal of the IGU and one bus bar is internal to the IGU. In the former embodiment, the area is used to form a seal with one face of the spacer used to form the IGU. Thus, wires or other connections to the bus bars extend between the spacer and the glass. Since many spacers are made of metal, such as conductive stainless steel, it is desirable to take measures to avoid short circuits due to electrical communication between the bus bar and the connector thereto and the metal spacer.

iii) logic for controlling electrochromic devices/windows

In some implementations, a controller (e.g., a local window controller, a network controller, a master controller, etc.) includes intelligent control logic for calculating, determining, selecting, or otherwise generating a tint state for one or more optically switchable windows (e.g., electrochromic windows) of a building. The control logic may be operable to determine a cloud cover condition based on sensor data from an infrared cloud detector system at the building and to use the determined cloud cover condition to determine a tint state of the optically switchable window. Such control logic may be used to implement a method for determining and controlling the level of tint required for one more electrochromic or other tintable window to take into account passenger comfort and/or energy savings considerations. In some cases, the control logic uses one or more logic modules. 11A-11C include schematic diagrams depicting some common inputs to each of the three logic modules A, B and C of the exemplary control logic of the disclosed implementations. Additional embodiments of modules A, B and C are described in International patent application PCT/US16/41344 entitled "CONTROL METHOD FOR TINTABLE WINDOWS" filed on 7/2016 and PCT/US15/29675 entitled "CONTROL METHOD FOR TINTABLE WINDOWS" filed on 5/2015, each of which is incorporated by reference in its entirety.

11A-11C include schematic diagrams depicting some common inputs to each of the three logic modules A, B and C of the exemplary control logic of the disclosed implementations. Each schematic drawing depicts a schematic side view of a room 1200 of a building having a table 1201 and an electrochromic window 1205 located between the exterior and interior of the building. The figure also depicts an infrared cloud detector system according to an example. In other implementations, another embodiment of the infrared cloud detector system described herein may be used. In the illustrated embodiment, the infrared cloud detector system includes an infrared cloud detector 1230 located on the roof of a building. The infrared cloud detector 1230 includes a housing 1232 having a cover made of a light diffusing material, an infrared sensor 1234 and a photosensor 1210 within the housing of the housing 1232, and an ambient temperature sensor 1236 located on the shadow surface of the housing 1232. The infrared sensor 1234 is configured to obtain a temperature reading T based on infrared radiation received from a region of the sky within its conical field of view 1235_IR. Ambient temperature sensor 1236 is configured to obtain an ambient temperature reading T of ambient air surrounding infrared cloud detector 1230_A. The infrared sensor 1234 includes an imaginary axis that is perpendicular to the sensing surface of the infrared sensor 1234 and passes through the center thereof. The infrared sensor 1234 is directed such that its sensing surface faces upward, and may receive infrared radiation from regions of the sky that are within its field of view 1235. Ambient temperature sensor 1236 is located on a shadow surface to avoid direct sunlight from striking itA sensing surface. Although not shown, infrared cloud detector 1230 also includes one or more structures that retain its components within housing 1232.

The infrared cloud detector system also includes a local window controller 1250 having a processor that can execute instructions stored in a memory (not shown) for implementing control logic for controlling the tint level of the electrochromic window 1205. The controller 1250 communicates with the electrochromic window 1205 to send control signals. The controller 1250 is also in communication (wirelessly or by wire) with the infrared sensor 1234 and the ambient temperature sensor 1236 to receive signals having temperature readings. Controller 1250 is also in communication (wirelessly or by wire) with photoreceptor 1210 to receive signals having visible light intensity readings.

According to certain aspects, the power/communication lines extend from the building or another structure to the infrared cloud detector 1230. In one implementation, the infrared cloud detector 1230 includes a network interface that can couple the infrared cloud detector 1230 to a suitable cable. The infrared cloud detector 1230 may communicate the data to the controller 1250 of the building or another controller (e.g., a network controller and/or a master controller) through a network interface. In some other implementations, the infrared cloud detector 1230 may additionally or alternatively include a wireless network interface capable of wireless communication with one or more external controllers. In some aspects, infrared cloud detector 1230 may also include a battery within or coupled with its housing to power the sensors and electronic components therein. The battery may provide such power instead of or in addition to power from a power source (e.g., from a building power source). In one aspect, infrared cloud detector 1230 further includes at least one photovoltaic cell, for example, on an outer surface of the housing. The at least one photovoltaic cell may provide power in place of or in addition to power provided by any other power source.

Fig. 11A shows the penetration depth of direct sunlight into a room 1200 through an electrochromic window 1205 between the exterior and the interior of a building that includes the room 1200. Penetration depth is a measure of the extent to which direct sunlight will penetrate into the room 1200. As shown, the penetration depth is measured in a horizontal direction away from the sill (bottom) of the window 1205. Typically, the window defines an aperture that provides an acceptance angle for direct sunlight. The penetration depth is calculated based on the geometry of the window (e.g., the size of the window), its position and orientation in the room, any fins or other external coverings outside the window, and the position of the sun (e.g., the sun angle of direct sunlight at a particular time of day and date). The outer shield of electrochromic window 1205 may be due to any type of structure that can shield the window, such as an overhang, a heat sink, and the like. In fig. 11A, there is a overhang 1220 above the electrochromic window 1205, the overhang 1220 blocking a portion of the direct sunlight entering the room 1200, thereby shortening the penetration depth.

Module a may be used to determine a tint level that takes into account the comfort of the occupants, avoiding direct sunlight through the electrochromic window 1205 onto the occupants or their active areas. The hue level is determined based on the calculated penetration depth of the direct sunlight into the room and the type of space in the room at a particular moment in time (e.g., a table, a lobby near a window, etc.). In some cases, the level of hue may also be based on sufficient natural light provided into the room. In some cases, the penetration depth is a value calculated at a future time to account for the transition time of the glass (the time required for window tinting, e.g., 80%, 90%, or 100% of the desired level of tint). The problem addressed in module a is that direct sunlight may penetrate deep into the room 1200 to shine directly on people working at the table or other active areas in the room. Publicly available programs can provide calculation of the sun's position and allow easy calculation of the penetration depth.

Fig. 11A-11C also show a table 1201 in a room 1200 as an example of the type of space associated with the activity area (i.e., the table) and the location of the activity area (i.e., the location of the table). Each space type is associated with a different level of hue for occupant comfort. For example, if the activity is a critical activity, such as an office work done at a desk or computer, and the desk is located near the window, the desired level of tint may be higher than if the desk was farther from the window. As another example, if the activity is non-critical, such as in a lobby, the desired hue level may be lower than the hue level of the same space with a table.

Fig. 11B illustrates direct sunlight and radiation entering the room 1200 through the electrochromic window 1205 under clear sky conditions, according to an implementation. The radiation may come from sunlight scattered by molecules and particles in the atmosphere. Module B determines the tone level based on the calculated value of irradiance flowing through the electrochromic window 1205 under clear sky conditions. Various software, such as the open source radar program, may be used to calculate a certain latitude, longitude, time of year, time of day, and directed clear sky irradiance for a given window.

Fig. 11C illustrates radiated light from the sky when it may be blocked or reflected by objects such as clouds and other buildings, according to an implementation. These obstacles and reflections are not considered in the clear sky radiation calculation. The radiated light from the sky is determined based on sensor data from sensors such as infrared cloud sensor 1234, photosensor 1210, and ambient temperature sensor 1236 of the infrared cloud detector system. The level of hue determined by module C is based on the sensor data. In many cases, the level of tint is based on the cloud cover condition determined using sensor data from the sensor. In general, operation of module B will determine the level of shade that causes the level of shade determined by module a to be dimmed (or unchanged), and operation of module C will determine the level of shade determined by module B to be dimmed (or unchanged).

Control logic may implement one or more of logic modules A, B and C separately for each electrochromic window 1205 in the building. Each electrochromic window 1205 may have a unique set of dimensions, orientation (e.g., vertical, horizontal, tilted at an angle), position, associated spatial type, etc. A profile with this and other information may be saved for each electrochromic window 1205. The configuration file may be stored in a computer readable medium of the local window controller 1250 of the electrochromic window 1205, or in a building management system ("BMS") described later in this disclosure. The profile may include information such as window configurations, occupancy look-up tables, information relating to the associated reference glass, and/or other data used by the control logic. The window configuration may include information such as the size of the electrochromic window 1205, the orientation of the electrochromic window 1205, the location of the electrochromic window 1205, and the like. A location description of the occupancy look-up table, the level of hue providing occupant comfort for certain types of spaces and penetration depths. That is, the color tone levels in the occupancy look-up table are designed to provide comfort to occupants who may be in the room 1200 from direct sunlight onto the occupants or their workspace. The type of space is a measure for determining how much coloration is needed to solve the occupant comfort issue for a given penetration depth and/or to provide comfortable natural lighting in the room. The spatial type parameter may take into account a number of factors. These factors include the type of work or other activity being performed within a particular room and location of the activity. The intensive work associated with detailed studies that require great attention may be of one type of space, while rest or conference rooms may be of a different type of space. Additionally, the position of a table or other work surface in the room relative to the window is a consideration in defining the type of space. For example, the space type may be associated with an individual occupant's office having a desk or other work space located near the electrochromic window 1205. As another example, the space type may be a lobby.

In certain embodiments, one or more modules of the control logic may determine a desired level of tint while accounting for energy savings other than occupant comfort. These modules can determine the energy savings associated with a particular tone level by comparing the performance of electrochromic window 1205 at that tone level to that of a reference glass or other standard reference window. The purpose of using this reference window may be to ensure that the control logic meets the requirements of municipal building codes or other requirements of the reference window used in the building site. Municipalities define reference windows using conventional low emissivity glass to control the amount of air conditioning load in a building. As an example of how the reference windows 1205 are suitable for the control logic, the logic may be designed such that the irradiance through a given electrochromic window 1205 is never greater than the maximum irradiance of the reference window specified by the respective municipality. In the disclosed embodiments, the control logic may use the solar thermal gain coefficient (SHGC) value of the electrochromic window 1205 at a particular tone level and the SHGC of the reference window to determine the energy savings using the tone level. Generally, the value of SHGC is the fraction of incident light of all wavelengths transmitted through the window. Although reference glass is described in many embodiments, other standard reference windows may be used. Typically, the SHGC of a reference window (e.g., a glass reference) is a variable that may be different for different geographic locations and window orientations and is based on regulatory requirements specified by the respective municipalities.

Typically, buildings are designed with heating, ventilation and air conditioning ("HVAC") systems that have the capacity to meet the maximum anticipated heating and/or air conditioning load required in any given situation. The calculation of the required capacity may take into account a datum glass or reference window required in the building at the particular location where the building is being constructed. Therefore, it is important that the control logic meet or exceed the functional requirements of the reference glass in order to allow the building designer to confidently determine how much HVAC capacity to place into a particular building. Because the control logic can be used to tint the window to provide additional energy savings to the reference glass, the control logic can be used to allow a building designer to have a lower HVAC capacity than is required using the reference glass specified by the specifications and standards.

Certain embodiments described herein assume energy savings by reducing air conditioning loads in a building. Thus, many implementations attempt to achieve the maximum coloration possible while taking into account the comfort level of occupants in the room with the window in question and the possible lighting load. However, in some climates, such as those with far north and south latitudes, heating may be more of a concern than air conditioning. Thus, the control logic can be modified, in particular the road surface can be changed in some circumstances, so that less coloring takes place, to ensure that the heating load of the building is reduced.

Fig. 12 depicts a flowchart 1400 showing general control logic for a method for controlling one or more electrochromic windows (e.g., electrochromic windows 1205) in a building, according to an embodiment. Control logic calculates the tint level of the window using one or more of modules A, B and C and sends instructions to transition the window to that tint level. At operation 1410, the calculations in the control logic are run 1 to n times at intervals timed by the timer. For example, the level of hue may be recalculated 1 to n times by one or more of modules A, B and C, and for time T_i＝T₁，T₂...T_nN is the number of recalculations performed, and n may be at least 1. In some cases, the logical calculations may be done at constant time intervals. In one case, the logical calculation is completed every 2 to 5 minutes. However, tone transitions of large pieces of electrochromic glass (e.g., up to 6 feet by 10 feet) can take as long as 30 minutes or more. For these large windows, the calculations may be performed on a less frequent basis, such as once every 30 minutes.

At operation 1420, the logic modules A, B and C perform calculations to determine that at a single time T_iOf each electrochromic window. These calculations may be performed by a processor of the controller. In certain embodiments, the control logic calculates how the window should transition before the actual transition. In these cases, the calculations in modules A, B and C are based on a future time, e.g., during or after completion of the conversion. For example, the future time used in the calculation may be a future time sufficient to allow the transition to complete after receiving the hue instruction. In these cases, the controller may send the tone instructions at the current time prior to the actual transition. By completing the transition, the window will transition to the level of tint required for that time.

At operation 1430, the control logic allows certain types of overrides of the algorithm to be disengaged at blocks A, B and C, and defines override tone levels at operation 1440 based on some other consideration. One type of overlay is a manual overlay. This is the coverage implemented by the end user occupying the room and determines the particular level of hue (coverage value) that may be needed. There may be instances where the user's manual coverage itself is covered. An example of coverage is high demand (or peak load) coverage, which is associated with the requirement of utilities in buildings where energy consumption is reduced. For example, on particularly hot days in a metropolitan area, it may be necessary to reduce the energy consumption of the entire municipality in order to avoid unduly imposing taxes on the energy production and delivery systems of the municipality. In this case, the building may be overlaid with tint levels from the control logic described herein to ensure that all windows have particularly high tint levels. Another example of an overlay may be whether there are no occupants on an example weekend of a room in a commercial office building. In these cases, the building may be detached from one or more modules related to occupant comfort, and all windows may have a low level of tinting in cold weather and a high level of tinting in warm weather.

At operation 1450, control signals for achieving the tint level are transmitted over the network to a power source in electrical communication with the electrochromic devices in one or more electrochromic windows in the building. In certain embodiments, the transfer of tint levels to all windows of a building may be accomplished with efficiency considerations. For example, if the recalculation of the tone level indicates that there is no need to change the tone from the current tone level, no instruction with an updated tone level is sent. As another example, a building may be divided into zones based on window size and/or location in the building. In one case, the control logic recalculates the tint level for the region with the smaller window more frequently than for the region with the larger window.

In some embodiments, the control logic in fig. 12 for implementing the control method for multiple electrochromic windows throughout a building may be on a single device, e.g., on a single master window controller. The device can perform calculations for each and every tintable window in a building and also provide an interface for communicating tint levels to one or more electrochromic devices in a single electrochromic window, for example in a multi-zone window or on multiple EC lite (lites) of an insulated glass unit. Some embodiments of a MULTI-ZONE window may be found in PCT application PCT/US14/71314 entitled "MULTI-ZONE EC WINDOWS," which is incorporated herein by reference in its entirety.

Also, there may be some adaptive components of the control logic of the embodiments. For example, the control logic may determine how an end user (e.g., an occupant) is attempting to override the algorithm at a particular time of day and utilize this information in a more predictive manner to determine the desired level of tint. In one case, the end user may be using a wall switch to override the level of tint provided by the control logic at a particular time of day to a coverage value. The control logic may receive information about these instances and change the control logic to change the level of tint to the override value at the time of day.

FIG. 13 is a schematic diagram illustrating block 1420 from the particular implementation of FIG. 12. The diagram shows that all three modules A, B and C are executed in sequence to calculate a single time T_iOf the final tint level of the particular electrochromic window. The final level of tint may be the maximum allowed transmittance of the window under consideration. Fig. 13 also shows some exemplary inputs and outputs of modules A, B and C. The calculations in blocks A, B and C are performed by a processor of a local window controller, a network controller, or a master controller. Although certain embodiments describe all three modules A, B and C used, other implementations may use one or more of modules A, B and C, or may use additional/different modules.

At operation 1470, the processor uses module a to determine a level of hue for occupant comfort to prevent direct glare from sunlight from penetrating the room. The processor uses module a to calculate the penetration depth of direct sunlight into the room from the position of the sun in the sky and the window configuration in the profile. The position of the sun is calculated from the latitude and longitude of the building and the time and date of the day. The occupancy lookup table and the space type are input from a configuration file for a particular window. Module a outputs the level of hue from module a to module B. The goal of module a is generally to ensure that direct sunlight or glare does not illuminate the occupant or his or her workspace. The level of hue from module a is determined to achieve this. Subsequent calculations of the level of hue in module B and module C may reduce energy consumption and may require even larger hues. However, if subsequent calculations based on the energy expenditure hue level indicate less hue than the coloration needed to avoid disturbing the occupant, the logic prevents the calculated higher level of transmittance from being performed to ensure occupant comfort.

At operation 1480, the tone level calculated in module A is input into module B. Typically, module B determines a level of shade that darkens (or does not change) the level of shade calculated in module B. The hue level is calculated based on the calculation of irradiance under clear sky conditions (irradiance of clear sky). The processor of the controller uses module B to calculate the irradiance of the clear sky of the electrochromic window based on the window orientation from the profile and based on the latitude and longitude of the building. These calculations are also based on the time and date of the day. Publicly available software, such as the radar program, is an open source program that may provide calculations for calculating irradiance of clear sky. The SHGC of the reference glass is also input to module B from the configuration file. The processor uses module B to determine a darker tint level than the tint level in a and delivers less heat than the reference glass calculated to deliver at maximum clear sky irradiance. The irradiance of the maximum clear sky is the highest irradiance level at all times calculated for clear sky conditions.

At operation 1490, the tone level from module B and the calculated clear sky irradiance are input to module C. Sensor readings are input to module C based on measurements made by infrared sensors, ambient temperature sensors, and/or photoreceptors. The processor uses module C to determine the cloud status based on the sensor readings and the actual irradiance. The processor also uses module C to calculate the irradiance delivered to the room if the window is tinted to a level of tint from module B in clear sky conditions. If the actual irradiance through the window with this level of hue is less than or equal to the irradiance through the window with the level of hue from module B based on the determined cloud cover condition from the sensor reading, the processor finds the appropriate level of hue using module C. Typically, the level of hue determined by operation of module C fades (or does not change) the level of hue determined by operation of module B. The level of hue determined in block C is the final level of hue in this embodiment.

Most of the information input to the control logic is determined by fixed information relating to latitude and longitude, time of day and date. This information describes the position of the sun relative to the building, and more specifically, relative to the window of the control logic being implemented. The position of the sun relative to the window provides information such as the penetration depth of direct sunlight into the room with the aid of the window. It also provides an indication of the maximum irradiance or solar radiant energy flux through the window. The calculated irradiance level may be based on sensor input that may indicate that there is a reduction based on the determined cloud cover condition or another obstacle between the window and the sun.

A program such as the open source program Radiance is used for window-based orientation and latitude and longitude coordinates of a building for a single time T_iAnd the maximum value at all times is used to determine the irradiance of a clear sky. The SHGC of the reference glass and the calculated irradiance of the largest clear sky are input into block B. Module B steps up the level of hue calculated in module a and selects a level of hue where the internal radiation is less than or equal to a reference internal irradiance, where: the internal irradiance is the hue level SHGC x clear sky irradiance, and the reference internal irradiance is the reference SHGC x maximum clear sky irradiance. However, when module a calculates the maximum tint of the glass, module B does not change tint to make it lighter. The level of hue calculated in block B is then input into block C. The calculated irradiance of the clear sky is also input into block C.

An embodiment of control logic for making a coloring decision using an infrared cloud detector system with a photoreceptor.

Fig. 14A is a flowchart 1500 depicting a particular implementation of the control logic of operation 1420 shown in fig. 13, in accordance with an embodiment. Although the control logic is described with respect to a single window, it should be understood that the control logic may be used to control multiple windows or regions of one or more windows.

At operation 1510, the control logic determines whether the time of day is during one of the following time periods: (i) a period beginning shortly before sunrise (e.g., beginning at a first time 45 minutes before sunrise, 30 minutes before sunrise, 20 minutes before sunrise, or other suitable period before sunrise) until slightly after sunrise (e.g., beginning at a second time 45 minutes after sunrise, 30 minutes after sunrise, 20 minutes after sunrise, or other suitable period) and (iii) a period beginning shortly before sunset (dusk) (e.g., beginning at a third time 45 minutes before sunset, 30 minutes before sunset, 20 minutes before sunset, or other suitable period before sunset) until sunset, or (ii) after (i) and before (iii). In one case, the sunrise time may be determined from measurements of the visible wavelength photoreceptor. For example, time period (i) may end at the point where the visible wavelength photoreceptor begins measuring direct sunlight, i.e., where the intensity reading of the visible light photoreceptor is at or above the minimum intensity value. Additionally or alternatively, the time period (iii) may be determined to end at a point where the intensity reading from the visible wavelength photoreceptor is at or below the minimum intensity value. In another embodiment, sunrise and/or sunset times may be calculated using a solar calculator, and the backlogs and time periods (i) and (iii) may be calculated by a defined time period (e.g., 45 minutes) before and after the calculated sunrise/sunset time. If it is determined at operation 1510 that the time of day is not during one of time periods (i), (ii), or (iii), the control logic determines that the time of day is in time period (iv), after time period (iii), and before time period (i), i.e., at night. In this case, the control logic passes through the night tone state (e.g., "clear") and proceeds to operation 1570 to determine if coverage is present, e.g., a coverage command is received in a signal from the operator. If it is determined that there is an override at operation 1560, the override value is the final tone level. If it is determined that there is no appropriate coverage, the level of hue from module C is the final level of hue. At operation 1570, control commands are sent over the network or to the electrochromic device of the window to transition the window to a final tint level, the time of day is updated, and the method returns to operation 1510. Conversely, if it is determined at operation 1510 that the time of day is during one of time periods (i), (ii), or (iii), then the time of day is between just before sunrise and sunset, and the control logic continues to determine at operation 1520 whether the solar azimuth angle is between the critical angles of the tintable window.

If it is determined by the control logic that the solar azimuth is outside the critical angle at operation 1520, then block A is bypassed, a "clear" hue level is passed to block B, and the calculation is performed using block B at operation 1540. If it is determined at operation 1520 that the solar azimuth is between the critical angles, then at operation 1530 the control logic in module A is used to calculate the penetration depth and appropriate tone level based on the penetration depth. The level of hue determined by module a is then input to module B and, at operation 1540, a calculation is made using module B.

At operation 1540, control logic from module B determines a tone level that darkens (or does not change) the tone level of module a. The hue level is calculated based on the calculation of irradiance under clear sky conditions (clear sky irradiance). Module B is used to calculate the irradiance of the clear sky of the window from the window orientations from the configuration file and based on the latitude and longitude of the building. These calculations are also based on the time and date of the day. Publicly available software, such as the radar program, is an open source program that may provide calculations for determining irradiance of clear sky. The SHGC of the reference glass is also input into module B from the configuration file. The processor uses the control logic of module B to determine a darker tone level than the tone level from module a and transmits less heat than the reference glass is calculated to transmit under irradiance of the largest clear sky. The irradiance of the maximum clear sky is the highest irradiance level at all times calculated for clear sky conditions.

At operation 1550, the hue level from module B, the calculated irradiance of clear sky, and sensor readings from the infrared sensor, the ambient temperature sensor, and the photoreceptor are input to module C. The control logic of module C determines the cloud cover condition from the sensor readings and determines the actual irradiance from the cloud cover condition. The control logic of module C also calculates the irradiance level that would be delivered into the room if the window were tinted to the tone level of module B in clear sky conditions. If the determined actual irradiance based on the cloud conditions through the window when coloring to the tone level from module B is less than or equal to the calculated irradiance through the window, the control logic in module C will decrease the tone level. In general, operation of module C will determine a level of tint that fades (or does not change) the level of tint determined by operation of module B.

At operation 1550, the control logic determines the level of tint from module C based on the sensor readings, and then proceeds to operation 1560 to determine if there is appropriate coverage, e.g., a coverage command received in a signal from the operator. If it is determined that there is coverage at operation 1560, the coverage value is the final tone level. If it is determined that there is no appropriate coverage, the level of hue from module C is the final level of hue. At operation 1570, control commands are sent over the network or to the electrochromic device of the window to transition the window to a final tint level, the time of day is updated, and the method returns to operation 1510.

FIG. 14B is a flowchart 1600 depicting a particular implementation of the control logic of operation 1550 shown in FIG. 14A. At operation 1610, one or more signals having temperature readings T obtained by an infrared sensor at particular sampling times are received at a processor_IRTemperature reading T obtained at sampling time by an ambient temperature sensor_AAnd the intensity readings obtained by the photoreceptor at the sampling time. Signals from the infrared sensor, the ambient temperature sensor, and the photoreceptor are received wirelessly and/or via a wired electrical connection. The infrared sensor obtains a temperature reading from infrared radiation received within its field of view. Infrared rayThe sensors are typically oriented toward an area of the sky of interest, such as an area above a building. The ambient temperature sensor is configured to be exposed to an external environment to measure an ambient temperature. The sensing surface of the photoreceptor is also generally directed towards the region of the sky of interest, and direct sunlight is blocked or diffused from illuminating the sensing surface.

If it is determined that the time of day is during any of time periods (i) or (iii) at operation 1620, the processor calculates a temperature reading T obtained by the infrared sensor_IRWith temperature readings T obtained at sample times by ambient temperature sensors_AThe difference delta (Δ) therebetween (operation 1630). Optionally (represented by the dashed line), a correction factor is applied to the calculated delta (Δ) (operation 1630). Some examples of correction factors that may be applied include humidity, sun angle/solar altitude angle, and field altitude.

In one embodiment, the processor also determines whether the infrared reading oscillates at a frequency greater than a second defined level at operation 1620. If the processor determines that the time of day is within time period (i) or (iii) and the infrared readings oscillate at a frequency greater than a second defined level at operation 1620, the processor applies operation 1690 to determine the cloud status using the photoreceptor readings. For example, if the photoreceptor reading is above some minimum intensity level, the processor may determine a "sunny" state, and if the photoreceptor reading is at or below the minimum intensity level, the processor may determine a "cloudy" state. If the system is still running, the method increments to the next sample time and returns to operation 1610.

At operation 1634, the processor determines whether the calculated delta (Δ) value is below a lower threshold (e.g., -5 degrees celsius, -2 degrees celsius, etc.). If it is determined that the calculated delta (Δ) value is below the lower threshold, the cloudiness condition is determined to be a "clear" state (operation 1636). During operation of the infrared cloud detector, the method then increments to the next sample time and returns to operation 1610.

If it is determined that the calculated delta (Δ) is above the lower threshold, the processor determines whether the calculated delta (Δ) is above an upper threshold (e.g., 0 degrees Celsius, 2 degrees Celsius, etc.) at operation 1640. If it is determined that the delta (Δ) calculated at operation 1640 is above the upper threshold, the processor determines the cloudiness condition as a "cloudy" condition (operation 1642).

At operation 1695, if the window is tinted to a level of tint from module B in clear sky conditions, the control logic determines the actual irradiance based on the cloud conditions and calculates an irradiance level to be delivered to the room. If the irradiance based on the cloud cover condition is less than or equal to the irradiance calculated through the window when coloring to the tone level from module B, then the control logic in module C will decrease the tone level from module B. The control logic then increments to the next sample time and returns to operation 1560.

If it is determined that the delta (Δ) calculated at operation 1640 is below the upper threshold, the processor determines the cloudiness condition as "intermittent cloudy day" or another intermediate state (operation 1650) and proceeds to operation 1695, which is described in detail above.

If it is determined at operation 1620 that the time of day is not during either of time periods (i) or (iii), then the time of day is during time period (ii) the day, and at operation 1670 the processor calculates a temperature reading T obtained by the infrared sensor_IRDifference from the intensity reading obtained by the photoreceptor. At operation 1680, the processor determines whether the calculated difference is within acceptable limits. If the processor determines at operation 1680 that the calculated difference is greater than the acceptable limit, the processor applies operation 1630 to calculate delta (Δ) and uses the calculated delta (Δ) to determine the cloud status as discussed above.

In one embodiment, the processor also determines whether the infrared readings oscillate at a frequency greater than a second defined level at operation 1660. If the processor determines at operation 1660 that the time of day is within the time period (ii) and the infrared readings oscillate at a frequency greater than a second defined level, the processor applies operation 1690 to determine a cloud status using the photoreceptor readings. For example, the processor may determine a "sunny" state if the photoreceptor reading is above some minimum intensity level, and a "cloudy" state if the photoreceptor reading is at or below the minimum intensity level. The control logic then proceeds to operation 1695, which is described in detail above.

If the processor determines at operation 1680 that the calculated difference is within acceptable limits, the photoreceptor reading is used to determine a cloud cover condition (operation 1690). For example, if the photoreceptor reading is above some minimum intensity level, the processor may determine a "sunny" state, and if the photoreceptor reading is at or below the minimum intensity level, the processor may determine a "cloudy" state. The control logic then proceeds to operation 1695, which is described in detail above.

In one embodiment, the processor also determines at operation 1670 whether the photoreceptor reading is oscillating at a frequency greater than a first defined level and whether the infrared reading is oscillating at a frequency greater than a second defined level. If the processor determines at operation 1680 that the calculated difference is within acceptable limits and the processor determines that the photoreceptor reading is oscillating at a frequency greater than the first defined level, the processor applies operation 1630 to calculate delta (Δ) and uses the calculated delta (Δ) to determine the cloud condition as discussed above. If the processor determines at operation 1680 that the calculated difference is not within acceptable limits and the processor determines that the infrared readings are oscillating at a frequency greater than a second defined level, the processor applies operation 1690 to determine a cloud status using the photoreceptor readings. For example, the processor may determine a "sunny" state if the photoreceptor reading is above some minimum intensity level, and a "cloudy" state if the photoreceptor reading is at or below the minimum intensity level. The control logic then proceeds to operation 1695, which is described in detail above.

Although a single infrared sensor is described as being included in the infrared cloud detector of certain implementations, according to another implementation, two or more infrared sensors may be used for redundancy in the event of one failure and/or obstruction by, for example, bird droppings or other environmental matter. In one aspect, two or more infrared sensors may be included that face different orientations to capture infrared radiation from different fields of view and/or different distances from a building/structure. If two or more infrared sensors are located within the housing of the infrared cloud detector, the infrared sensors are typically offset from each other by a sufficient distance to reduce the likelihood that a shield will affect all of the infrared sensors. For example, the infrared sensors may be separated by at least about one inch or at least about two inches.

It should be understood that the invention as described above may be implemented in the form of control logic using computer software in a modular or integrated manner. Based on the disclosure and teachings provided herein, a person of ordinary skill in the art will know and appreciate other ways and/or methods to implement the present invention using hardware and a combination of hardware and software.

Any of the software components or functions described herein may be implemented as software code executed by a processor using any suitable computer language, such as Java, C + + or Python, using, for example, conventional or object-oriented techniques. The software code may be stored as a series of instructions or commands on a computer readable medium, such as a Random Access Memory (RAM), a Read Only Memory (ROM), a magnetic medium such as a hard drive or floppy disk, a magnetic disk, or an optical medium such as a CD-ROM. Any such computer-readable medium may reside on or within a single computing device, and may exist on or within different computing devices within a system or network.

While the foregoing invention has been described in some detail for purposes of clarity of understanding, the described embodiments are to be considered as illustrative and not restrictive. It will be apparent to those of ordinary skill in the art that certain changes and modifications may be practiced within the scope of the appended claims.

One or more features from any embodiment may be combined with one or more features of any other embodiment without departing from the scope of this disclosure. Moreover, modifications, additions, or omissions may be made to any of the embodiments without departing from the scope of the disclosure. The components of any embodiment may be integrated or separated according to particular needs without departing from the scope of the present disclosure.

Claims

1. An infrared cloud detector system at a venue, the system comprising:

an infrared sensor configured to measure a sky temperature based on infrared radiation;

an ambient temperature sensor configured to measure an ambient temperature; and

logic configured to determine a cloud status using (I) a difference between a measured sky temperature from the infrared sensor and a measured ambient temperature from the ambient temperature sensor and (II) one or more correction factors, wherein the logic is configured to adjust the difference using the correction factors based on humidity, insolation angle/solar altitude, and/or altitude at the site.

2. The infrared cloud detector system of claim 1, wherein the determined cloud state is associated with a region of the sky within a field of view of the infrared sensor.

3. The infrared cloud detector system of claim 1, wherein the infrared sensor is one of an infrared thermometer, an infrared radiometer, an infrared atmospheric radiometer, and an infrared pyrometer.

4. The infrared cloud detector system of claim 1, wherein the infrared sensor is configured to detect infrared radiation having a radiation wavelength in a range of 8 microns to 14 microns.

5. The infrared cloud detector system of claim 1, wherein the infrared sensor is configured to detect infrared radiation having a radiation wavelength above 5 μ ι η.

6. The infrared cloud detector system of claim 1, further comprising a housing, wherein the infrared sensor is located within an enclosure of the housing.

7. The infrared cloud detector system of claim 6, wherein the ambient temperature sensor is located on an outer surface of the housing.

8. The infrared cloud detector system of claim 6, wherein the housing includes a light diffusing material between the infrared sensor and an external environment.

9. The infrared cloud detector system of claim 8, wherein the light-diffusing material has a thinned region between the infrared sensor and the external environment.

10. The infrared cloud detector system of claim 1, wherein the logic is further configured to determine a tint state of one or more electrochromic windows of a building based on the determined cloud state, and configured to send a control signal to transition the one or more electrochromic windows to the determined tint state.

11. The infrared cloud detector system of claim 10, wherein the infrared cloud detector system is located on a roof of the building.

12. The infrared cloud detector system of claim 1, wherein the logic is further configured to: determining the cloud status as "sunny" if the difference is below a lower threshold and as "cloudy" if the difference is above an upper threshold.

13. The infrared cloud detector system of claim 12, wherein the logic is further configured to determine the cloud state as an intermediate state if the difference is above the lower threshold and below the upper threshold.

14. An infrared cloud detector system at a venue, the system comprising:

an ambient temperature sensor for measuring an ambient temperature;

a photoreceptor configured to measure visible light intensity; and

logic configured to determine a cloud state, wherein:

(a) if the time of day is:

(i) a first time period between a first time before a sunrise time and a second time after said sunrise time, or

(ii) A second time period between a third time prior to the sunset time and the sunset time,

determining the cloud state using a difference between a measured sky temperature from the infrared sensor and a measured ambient temperature from the ambient temperature sensor, wherein the third time is after the second time; and

(b) if the time of day is:

(iii) a third time period between the second time and the third time,

the cloud status is determined based on the measured intensity of visible light from the photoreceptor.

15. The infrared cloud detector system of claim 14, wherein it is configured to (i) determine that the cloud status is "sunny" if the determined difference is below a lower threshold, and (ii) determine that the cloud status is "cloudy" if the determined difference is above an upper threshold.

16. The infrared cloud detector system of claim 15, wherein the logic is configured to adjust the difference between a measured sky temperature and a measured ambient temperature using one or more correction factors prior to determining the cloud state.

17. The infrared cloud detector system of claim 15, wherein the determined cloud state is associated with a region of the sky within a field of view of the infrared sensor.

18. The infrared cloud detector system of claim 14, wherein the logic configured to determine the cloud status based on a measured intensity of visible light from the photoreceptor comprises: determining that the cloud status is "sunny" if the measured intensity of visible light is above a minimum value, and determining that the cloud status is "cloudy" if the measured intensity of visible light is below the minimum value.

19. The infrared cloud detector system of claim 14, wherein the infrared sensor is one of an infrared thermometer, an infrared radiometer, an infrared atmospheric radiometer, and an infrared pyrometer.

20. The infrared cloud detector system of claim 14, wherein the infrared sensor is configured to detect infrared radiation having a wavelength ranging between 8 microns and 14 microns.

21. The infrared cloud detector system of claim 14, further comprising a housing, wherein the infrared sensor is located within an enclosure of the housing.

22. The infrared cloud detector system of claim 21, wherein the ambient temperature sensor is located on an outer surface of the enclosure.

23. The infrared cloud detector system of claim 21, wherein the housing includes a light diffusing material between the infrared sensor and an external environment.

24. The infrared cloud detector system of claim 23, wherein the light-diffusing material has a first thinned region between the infrared sensor and the external environment.

25. The infrared cloud detector system of claim 24, wherein

The photoreceptor is positioned in the shell of the shell; and

the light diffusing material has a second thinned region between the photoreceptor and the external environment.

26. The infrared cloud detector system of claim 14, wherein the logic is also configured to determine a tint state of one or more electrochromic windows of a building based on the determined cloud state, and configured to send instructions to transition the one or more electrochromic windows to the determined tint state.

27. The infrared cloud detector system of claim 26, wherein the infrared cloud detector system is located on a roof of the building.

28. An infrared cloud detector method, comprising:

receiving a sky temperature reading from an infrared sensor and an ambient temperature reading from an ambient temperature sensor;

calculating a difference between the sky temperature reading and the ambient temperature reading; and

determining a cloud state using (I) the difference between the sky temperature reading and the ambient temperature reading and (II) one or more correction factors, the difference adjusted using the one or more correction factors based on humidity, sun angle/solar altitude angle, and/or altitude at the venue.

29. The infrared cloud detector method of claim 28, further comprising:

determining that the cloud status is "clear" if the difference is below a lower threshold; and

determining that the cloud status is "cloudy" if the difference is above an upper threshold.

30. The infrared cloud detector method of claim 29, further comprising: determining that the cloud state is an intermediate state if the difference is above the lower threshold and below the upper threshold.

31. The infrared cloud detector method of claim 30, wherein said intermediate state is "intermittent cloudy".

32. The infrared cloud detector method of claim 29, wherein said lower threshold is in a range of-5 degrees celsius to-10 degrees celsius.

33. The infrared cloud detector method of claim 32, wherein said upper threshold is in the range of-5 degrees celsius to 0 degrees celsius.

34. The infrared cloud detector method of claim 28, further comprising:

determining a tint state of one or more electrochromic windows of a building based on the determined cloud state; and

instructions are sent to transition one or more electrochromic windows to a final tint state.

35. The infrared cloud detector method of claim 34, wherein said infrared sensor and said ambient temperature sensor are located on a roof of said building.

36. An infrared cloud detector method, comprising:

receiving a sky temperature reading from an infrared sensor, an ambient temperature reading from an ambient temperature sensor, and an intensity reading from a photoreceptor;

determining whether the time of day is:

(i) a first time period between a first time before sunrise and a second time after sunrise;

(ii) a second time period between a third time before a sunset time and the sunset time, wherein the third time is after the second time;

(iii) a third time period between the second time and the third time;

(iv) a fourth time period at night time after the sunset time and before the first time; and

determining a cloud status using the difference between the sky temperature reading and the ambient temperature reading if it is determined that the time of day will be at the first time period, the second time period, or the fourth time period; and

using the intensity readings to determine the cloud status if it is determined that the time of day will be in the third time period.

37. The infrared cloud detector method of claim 36, wherein using the difference between the sky temperature reading and the ambient temperature reading to determine a cloud state comprises:

38. The infrared cloud detector method of claim 37, further comprising: determining that the cloud state is an intermediate state if the difference between the sky temperature reading and the ambient temperature reading is above the lower threshold and below an upper threshold.

39. The infrared cloud detector method of claim 37, wherein said lower threshold is in a range of-5 degrees celsius to-10 degrees celsius.

40. The infrared cloud detector method of claim 39, wherein said upper threshold is in the range of-5 degrees Celsius to 0 degrees Celsius.

41. The infrared cloud detector method of claim 37, wherein determining the cloud state using the intensity readings comprises:

determining that the cloud status is "clear" if the intensity reading is above a minimum value; and

if the intensity reading is below a minimum value, the cloud status is determined to be "cloudy".

42. The infrared cloud detector method of claim 41, further comprising:

determining a tint state for one or more electrochromic windows of a building based on the determined cloud state; and

sending instructions to transition the one or more electrochromic windows to the determined hue state.

43. The infrared cloud detector method of claim 42, wherein determining the tint state of the one or more electrochromic windows comprises:

determining a first tonal state using one or more of the calculated irradiance of clear sky and the calculated penetration depth of direct sunlight into a room in which the one or more electrochromic windows are disposed;

determining that the tint state is a nighttime tint state if it is determined that the time of day will be at the fourth time period;

determining the tint state that is higher than the first tint state if it is determined that the time of day will be at the first time period, the second time period, or the third time period and the cloud state is determined to be "cloudy"; and

determining that the tint state is the first tint state if it is determined that the time of day is to be at the first time period, the second time period, or the third time period and the cloud state is determined to be "clear".

44. The infrared cloud detector method of claim 36, wherein the sky temperature reading from the infrared sensor and the ambient temperature reading from the ambient temperature sensor are received via a network.