Energy management for sensors

The present disclosure is directed to a method for reducing power consumption of a sensor. The method includes determining if a predetermined condition has been met to change at least one of a sensing rate or a sensor resolution, and changing at least one of the sensing rate or sensor resolution if it is determined that the predetermined condition has been met.

BACKGROUND

1. Technical Field

The present disclosure is directed to systems, apparatus, and methods for improving wireless HVAC components, and in particular, HVAC sensors and HVAC controllers having reduced power consumption, lower manufacturing costs, and increased reliability.

2. Background of Related Art

Heating, ventilation, and air conditioning systems (HVAC systems) typically utilize one or more sensors, thermostats, and/or HVAC controllers to monitor environmental conditions in a building and to operate HVAC equipment installed at the building. Traditional systems utilize components which are interconnected using traditional hard-wiring techniques using electrical conductors routed within the physical structure. Hard-wired systems are generally reliable, but the costs of cabling and installation are high. This is particularly true when installing devices in existing structures where cabling must be snaked through walls and ceilings.

More recently, the use of wireless HVAC devices has become popular since these devices are cheap and easy to install. Existing wireless devices may have drawbacks in that the batteries used in these devices have a limited lifespan and require periodic maintenance and replacement to ensure the HVAC system continues to function reliably. A wireless HVAC device which offers reduced power consumption, lower manufacturing costs, and increased reliability would be a welcome advance in the art.

For example, traditional CO2sensors consume quite a bit of power to accurately read levels of CO2in the local environment. The NDIR (non-dispersive infra-red) process that sensors presently use includes multiple factors that affect the power consumption. The technology of measuring the absorption of light due to the presence of CO2requires the generation of a specific light frequency at a known power level, which is energy intensive. In some instances, the received light intensity fluctuates, thereby making the individual measurements “noisy.” Sensors typically take multiple readings in succession and average or filter them together to reduce the effect of noise, and to present a more stable and accurate value as the output of the sensor. However, each sensor sample uses some discrete amount of total battery energy.

SUMMARY

In accordance with at least one aspect, the present disclosure is directed to a method for reducing power consumption of a sensor. The method includes determining if a predetermined condition has been met to change at least one of a sensing rate or a sensor resolution, and changing at least one of the sensing rate or sensor resolution if it is determined that the predetermined condition has been met.

In another aspect, the method may include sensing a monitored gas in a local atmosphere.

In another aspect, sensing the amount of the monitored gas may include sensing at least one of ethylene, CO, methane, O2, H2S, CO2, or other volatile organic compound gases.

In another aspect, determining if the predetermined condition has been met may include determining an amount or proportion of the monitored gas in the local atmosphere.

In another aspect, determining if the predetermined condition has been met may include determining a rate of change of the amount of the monitored gas over a time.

In another aspect, determining if the predetermined condition has been met may include comparing the rate of change of the amount of the monitored gas to a threshold rate of change to determine whether to change the sensing rate or sensor resolution.

In another aspect, determining if the predetermined condition has been met may include determining an occupancy state of a building.

In another aspect, determining the occupancy state may include referencing a predetermined schedule and comparing a local clock to the predetermined schedule to determine the occupancy state of the building.

In another aspect, changing the sensing rate or the sensor resolution may include reducing the sensing rate or the sensor resolution to a minimum safe sensing rate or minimum safe sensor resolution.

In another aspect, reducing the sensing rate may include reducing the sensing rate from about 1 sensing per minute to about 1 sensing per hour.

In another aspect, reducing the sensor resolution may include reducing an amount of samples per sensor reading.

In accordance with another aspect of this disclosure, a sensor for an HVAC system includes a processor and a memory, and an energy management module stored in the memory and configured to be executed by the processor. The energy management module is configured for determining if a predetermined condition has been met to change at least one of a sensing rate or a sensor resolution, and changing at least one of the sensing rate or sensor resolution if it is determined that the predetermined condition has been met.

In another aspect, determining if the predetermined condition has been met may include determining an amount or proportion of a monitored gas in a local atmosphere.

In another aspect, determining if the predetermined condition has been met may include determining a rate of change of the amount of the monitored gas over a time.

In another aspect, determining if the predetermined condition has been met may include comparing the rate of change of the amount of the monitored gas to a threshold rate of change to determine whether to change the sensing rate or sensor resolution.

In another aspect, determining if the predetermined condition has been met may include determining an occupancy state of a building.

In another aspect, determining the occupancy state may include referencing a predetermined schedule and comparing a local clock to the predetermined schedule to determine the occupancy state of the building.

In another aspect, changing the sensing rate or the sensor resolution may include reducing the sensing rate or the sensor resolution to a minimum safe sensing rate or minimum safe sensor resolution.

In another aspect, reducing the sensing rate may include reducing the sensing rate from about 1 sensing per minute to about 1 sensing per hour.

In another aspect, reducing the sensor resolution may include reducing an amount of samples per sensor reading.

In accordance with another aspect of this disclosure, a system for reducing power consumption of sensors includes at least one computer server configured to be in communication with at least one sensor, and a power management module stored on the server. The energy management module is configured for determining if a predetermined condition has been met to change at least one of a sensing rate or a sensor resolution of the at least one sensor, and changing at least one of the sensing rate or sensor resolution if it is determined that the predetermined condition has been met.

In another aspect, determining if the predetermined condition is met may include receiving condition data from the sensor.

In another aspect, changing at least one of the sensing rate or sensor resolution may include outputting a command to the sensor to change at least one of the sensing rate or the sensor resolution.

The various aspects of the present disclosure mentioned above are described in further detail with reference to the aforementioned figures and the following detailed description of exemplary embodiments.

DETAILED DESCRIPTION

Particular illustrative embodiments of the present disclosure are described hereinbelow with reference to the accompanying drawings; however, the disclosed embodiments are merely examples of the disclosure, which may be embodied in various forms. Well-known functions or constructions and repetitive matter are not described in detail to avoid obscuring the present disclosure in unnecessary or redundant detail. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present disclosure in virtually any appropriately detailed structure. In this description, as well as in the drawings, like-referenced numbers represent elements which may perform the same, similar, or equivalent functions. The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments. The word “example” may be used interchangeably with the term “exemplary.”

The present disclosure is described herein in terms of functional block components and various processing steps. It should be appreciated that such functional blocks and/or processing steps may be realized by any number of hardware and/or software components configured to perform the specified functions. For example, the present disclosure may employ various integrated circuit components, e.g., memory elements, processing elements, logic elements, look-up tables, and the like, which may carry out a variety of functions under the control of one or more microprocessors or other control devices.

Similarly, the software elements of the present disclosure may be implemented with any programming or scripting language such as C, C++, C#, Java, COBOL, assembler, PERL, Python, PHP, or the like, with the various algorithms being implemented with any combination of data structures, objects, processes, routines or other programming elements. The object code created may be executed by any device, on a variety of operating systems, including without limitation RTOS, Apple OSX®, Apple iOS®, Google Android®, HP WebOS®, Linux, UNIX®, Microsoft Windows®, and/or Microsoft Windows Mobile®.

It should be appreciated that the particular implementations described herein are illustrative of the disclosure and its best mode and are not intended to otherwise limit the scope of the present disclosure in any way. Examples are presented herein which may include data items which are intended as examples and are not to be construed as limiting. Indeed, for the sake of brevity, conventional data networking, application development and other functional aspects of the systems (and components of the individual operating components of the systems) may not be described in detail herein. It should be noted that many alternative or additional functional relationships or physical or virtual connections may be present in a practical electronic system or apparatus. In the discussion contained herein, the terms user interface element and/or button are understood to be non-limiting, and include other user interface elements such as, without limitation, pushbutton, a proximity sensor, a hyperlink, clickable image, and the like.

As will be appreciated by one of ordinary skill in the art, aspects of the present disclosure may be embodied as a method, a data processing system, a device for data processing, and/or a computer program product. Certain aspects of the present disclosure may take the form of a computer program product on a computer-readable storage medium having computer-readable program code means embodied in the storage medium. Any suitable computer-readable storage medium may be utilized, including hard disks, CD-ROM, DVD-ROM, optical storage devices, magnetic storage devices, semiconductor storage devices (e.g., EEPROM, mask ROM, flash memory, USB thumb drives) and/or the like.

One skilled in the art will also appreciate that, for security and/or any other suitable reason, any components, data structures, and communications links may include any of various suitable security features, such as firewalls, access codes, encryption, de-encryption, compression, decompression, and/or the like. In some instances, the steps recited herein may be executed in any order and are not limited to the order presented.

Certain embodiments are disclosed herein which operate in accordance with the ZigBee® wireless mesh networking standards, however, it should be understood that embodiments of the present disclosure are applicable to any wired or wireless network architecture, including without limitation Z-Wave®, in which the features and advantages discussed herein may be advantageously employed.

Referring toFIG. 1, in accordance with the present disclosure, a method100for reducing power consumption of a sensor (e.g., a CO2sensor or any other suitable sensor) includes determining (e.g., in block101) if a predetermined condition has been met to change at least one of a sensing rate or a sensor resolution, and changing (e.g., in block103) at least one of the sensing rate or sensor resolution if it is determined that the predetermined condition has been met.

The method100may include sensing a monitored gas in a local atmosphere (e.g., where the sensor is located). In certain embodiments, sensing the amount of the monitored gas may include sensing at least one of ethylene, CO, methane, O2, H2S, CO2, or other volatile organic compound gases.

Determining101if the predetermined condition has been met may include determining an amount or proportion of the monitored gas in the local atmosphere. Determining101if the predetermined condition has been met may include determining a rate of change of the amount of the monitored gas over a time. For example, determining101if the predetermined condition has been met may include comparing the rate of change of the amount of the monitored gas to a threshold rate of change to determine whether to change the sensing rate or sensor resolution.

In such a case, if a rate of change of the monitored gas is below the threshold rate of change, it can be determined that the predetermined condition has been met to reduce sensor resolution and/or sensing rate. This may allow less use of energy resources while ensuring that no unsafe conditions are created.

In certain embodiments, determining101if the predetermined condition has been met may include determining an occupancy state of a building. For example, determining the occupancy state may include referencing a predetermined schedule and comparing a local clock (e.g., on the sensor) to the predetermined schedule to determine the occupancy state of the building. In certain embodiments, determining101if the predetermined condition has been met may include determining if an HVAC system is in an off state such that a reading would go wasted (e.g., which can be a function of occupancy state).

In certain embodiments, e.g., after block101as described above, changing103the sensing rate or the sensor resolution may include reducing the sensing rate or the sensor resolution to a minimum safe sensing rate or minimum safe sensor resolution. In this case, a predetermined minimum safe time-lapse or error value can be calculated to estimate that the sensed condition (e.g., CO2levels) cannot rise above a threshold safety level in the time between sensing and/or accounting for error due to resolution. It is contemplated that such minimum safe rates or resolutions can be calculated to any suitable degree of certainty based on any suitable criteria (e.g., past CO2levels data for the location of the sensor such as maxima, minima, averages, date/time correlations, environmental correlations).

In certain embodiments, reducing the sensing rate may include reducing the sensing rate from about 1 sensing per minute to about 1 sensing per hour. Any other suitable sensing rate reduction is contemplated herein. It is also contemplated that changing101can include increasing the sensing rate (e.g., from about 1 hour to about 1 min) if the predetermined condition to reduce the sensing rate is lost at any suitable point after reducing the sensing rate.

In certain embodiments, reducing the sensor resolution may include reducing an amount of samples per sensor reading. For example, certain sensors may take a plurality of samples (e.g., simultaneously or successively) at a given reading to account for noise reduction of the reading. Reducing the amount of samples at each reading can reduce the accuracy/resolution of each reading due to less noise/error cancellation. Since each sample requires a discrete amount of energy for a powered sensor, a reduction in samples can reduce energy consumption. As is appreciated by those ordinarily skilled in the art, the sample amount can be reduced to a minimum safe resolution as described above.

In certain embodiments, the method100can include using a fixed schedule of sensing rate and/or sensor resolution to modify the performance of the sensor200. In other embodiments, it is contemplated that the new sensing rate and/or sensor resolution can be calculated (e.g., by the sensor200) in real time or in any suitable interval.

Referring toFIG. 2, in accordance with another aspect of this disclosure, a sensor200for an HVAC system (e.g., a CO2sensor) may include a processor201, a memory203, and an energy management module205stored in the memory203that is configured to be executed by the processor205. The energy management module205may include any suitable logic hardware and/or software to execute an energy management routine (e.g., method100). The energy management module205can be configured to perform any suitable portion or all of method100as described above. The sensor200may be battery powered or powered via any other suitable means.

For example, energy management module205may be configured for determining if a predetermined condition has been met to change at least one of a sensing rate or a sensor resolution. The energy management module205may also be configured to change at least one of the sensing rate or sensor resolution if it is determined that the predetermined condition has been met. Any and all other suitable portions of method100may or may not be performed by energy management module205.

Referring toFIG. 3, an embodiment of a sensor device300for an HVAC system is shown. The sensor device300includes a CO2sensor301and a radio module303that is connected to the CO2sensor301. The CO2sensor301may include any suitable portions or all of sensor200as described above (e.g., energy management module205), and/or any other suitable features. For example, the sensor device300may include an LCD display305(e.g., including a backlight) operatively connected to an LCD driver307to display images (e.g., numbers, letters) on the LCD display305. The sensor device300can also include a keypad and/or one or more switches309which allow a user to input commands into the sensor device300. The sensor device300can also include one or more batteries311as well as other suitable circuitry (e.g., sleep fail circuitry to prevent a sleep mode failure).

In certain embodiments, an input indication that the sensor301is in safe mode may be programmed and/or manually switched by a user before or after placing the sensor301into service. For example, if a user knows that the location or intended use of a particular sensor301requires full time maximum sensing for liability or safety reasons, then the user may operate a suitable control (e.g., the keypad and/or switches309, a touch screen display, a digital command from a remote device) to instruct the energy management module205to shut off and/or avoid changing the sensing rate and/or sensor resolution.

Referring toFIGS. 2 and 4, the sensor (e.g., sensor200as shown) can be part of a system400for managing energy usage of one or more sensors200(e.g., for reducing power consumption of sensors200). For example, the sensor200can be configured to be connected (wired or wireless) to remote server401. The energy management module200may alternatively and/or additionally be configured to receive energy management data (e.g., through transmitter/receiver (TX/RX)209) from a power management module407of a remote server401. In such a case, the energy management module205may or may not include one or more portions of method100, and power management module407may be configured to operate at least one suitable portion of method100. For example, the power management module407can perform the functions of the energy management module as described above to provide a sensor200with data/instruction to reduce sensing rate and or sensor resolution.

In this regard, primary sensor207can take readings and provide data to the memory203and/or energy management module205. The sensor200may also include a state sensor211for sensing one or more suitable conditions of the sensor200or environment around the sensor200(e.g., temperature, pressure, age of the sensor) in addition to the primary sensor207(e.g., CO2sensing element). Such data can be received by the energy management module205.

The energy management module205can then transmit one or more data points (e.g., a plurality of data points of a period of time) to the power management module407of the remote server401via the TX/RX209. The energy management module205may additionally or alternatively send a request for energy management to the server401in order to notify the power management module407that the sensor200requires power management instruction from the server401. The power management module407may include a subroutine to provide similar instructions to any other sensors200in a related group (e.g., all similar sensors in a given location), for example.

The power management module407may use the data received from the energy management module205of the sensor200and use it to determine if one or more predetermined conditions have been met (e.g., sensor variance below a threshold, building occupancy status) as described above with respect to method100. The power management module407may then output a command to the sensor200to cause the sensor200to change (e.g., reduce) the sensing rate and/or the sensor resolution if it is determined that the predetermined condition has been met.

For example, occupancy information can be sent to the sensor200either as a state variable (occupied or unoccupied) or as a time remaining until the mode changes to occupied. Similarly the desired level of resolution can be communicated to the sensor200to allow the sensor200to provide the proper level of significant digits in the reported value.

While embodiments of this disclosure are directed to sensors (e.g., battery powered CO2sensors) it is contemplated that the methods and systems described herein may be implemented on any suitable powered electronic device for energy usage management, whether battery powered or not.

Utilizing the hereinabove described systems, devices, and methods, limited power in the batteries can be conserved allowing for the operable life of sensors to increase substantially (e.g, by double). For example, readings can be taken only when needed (e.g., only when the HVAC control system is on) and/or the resolution of each reading can be reduced to avoid expending energy when it is unnecessary (e.g., when a building is in a steady state and/or unoccupied).

Aspects

It is noted that any of aspects described below can be combined with each other in any suitable combination as is appreciated by those having ordinary skill in the art.

Aspect 1. A method for reducing power consumption of a sensor. The method includes determining if a predetermined condition has been met to change at least one of a sensing rate or a sensor resolution, and changing at least one of the sensing rate or sensor resolution if it is determined that the predetermined condition has been met.

Aspect 2. The method may include sensing a monitored gas in a local atmosphere.

Aspect 3. Sensing the amount of the monitored gas may include sensing at least one of ethylene, CO, methane, O2, H2S, CO2, or other volatile organic compound gases.

Aspect 4. Determining if the predetermined condition has been met may include determining an amount or proportion of the monitored gas in the local atmosphere.

Aspect 5. Determining if the predetermined condition has been met may include determining a rate of change of the amount of the monitored gas over a time.

Aspect 6. Determining if the predetermined condition has been met may include comparing the rate of change of the amount of the monitored gas to a threshold rate of change to determine whether to change the sensing rate or sensor resolution.

Aspect 7. Determining if the predetermined condition has been met may include determining an occupancy state of a building.

Aspect 8. Determining the occupancy state may include referencing a predetermined schedule and comparing a local clock to the predetermined schedule to determine the occupancy state of the building.

Aspect 9. Changing the sensing rate or the sensor resolution may include reducing the sensing rate or the sensor resolution to a minimum safe sensing rate or minimum safe sensor resolution.

Aspect 10. Reducing the sensing rate may include reducing the sensing rate from about 1 sensing per minute to about 1 sensing per hour.

Aspect 11. Reducing the sensor resolution may include reducing an amount of samples per sensor reading.

Aspect 12. A sensor for an HVAC system includes a processor and a memory, and an energy management module stored in the memory and configured to be executed by the processor. The energy management module is configured for determining if a predetermined condition has been met to change at least one of a sensing rate or a sensor resolution, and changing at least one of the sensing rate or sensor resolution if it is determined that the predetermined condition has been met.

Aspect 13. Determining if the predetermined condition has been met may include determining an amount or proportion of a monitored gas in a local atmosphere.

Aspect 14. Determining if the predetermined condition has been met may include determining a rate of change of the amount of the monitored gas over a time.

Aspect 15. Determining if the predetermined condition has been met may include comparing the rate of change of the amount of the monitored gas to a threshold rate of change to determine whether to change the sensing rate or sensor resolution.

Aspect 16. Determining if the predetermined condition has been met may include determining an occupancy state of a building.

Aspect 17. Determining the occupancy state may include referencing a predetermined schedule and comparing a local clock to the predetermined schedule to determine the occupancy state of the building.

Aspect 18. Changing the sensing rate or the sensor resolution may include reducing the sensing rate or the sensor resolution to a minimum safe sensing rate or minimum safe sensor resolution.

Aspect 19. Reducing the sensing rate may include reducing the sensing rate from about 1 sensing per minute to about 1 sensing per hour.

Aspect 20. Reducing the sensor resolution may include reducing an amount of samples per sensor reading.

Aspect 21. A system for reducing power consumption of sensors includes at least one computer server configured to be in communication with at least one sensor, and a power management module stored on the server. The energy management module is configured for determining if a predetermined condition has been met to change at least one of a sensing rate or a sensor resolution of the at least one sensor, and changing at least one of the sensing rate or sensor resolution if it is determined that the predetermined condition has been met.

Aspect 22. Determining if the predetermined condition is met may include receiving condition data from the sensor.

Aspect 23. Changing at least one of the sensing rate or sensor resolution may include outputting a command to the sensor to change at least one of the sensing rate or the sensor resolution.