Self-powered temperature sensing devices and methods of monitoring thermal performance

Abstract

A self-powered temperature measurement device monitors thermal performance of a pipe of a thermoelectric generator. The device includes a temperature sensor coupled to an external surface of the pipe; a thermoelectric generator (TEG) for harvesting power from a temperature gradient between heat on the external surface and an ambient temperature; a processor for determining a temperature measurement, based on an input from the temperature sensor; and a wireless transmitter for transmitting temperature data from the device to the processor.

Description

SELF-POWERED TEMPERATURE SENSING DEVICES AND METHODS OF MONITORING THERMAL PERFORMANCECROSS-REFERENCE TO RELATED APPLICATION

[0001] The present application claims the benefit of and priority to U.S. provisional patent application no. 63 / 697,257, filed September 20, 2024, the contents of which are incorporated herein by reference.FIELD

[0002] The present disclosure relates to temperature sensors, more specifically to temperature sensors for monitoring thermal performance in an industrial environment, and in particular to self-powered temperature sensors based on thermoelectric generators.BACKGROUND

[0003] Cycle isolation in an industrial environment, such as a power plant, is the process of evaluating thermal performance. The process captures lost power by monitoring valve system flows and identifying any leakage, for example, using temperature monitoring. For example, when using a steam turbine, steam flow through steam pipes in the power plant may be isolated by valves. By monitoring temperatures associated with a system flow immediately upstream and downstream of a valve, leaks can be identified based on temperature differentials. For example, detection of a rising or high temperatures downstream of a valve may indicate steam leakage. In this regard, steam leakage may reduce the thermal performance of the power plant, representing lost power generation and negatively impacting revenue.

[0004] Leakage may be caused by many factors, including aging equipment and / or infrastructure, excess differential pressure, foreign material in the valve,tank level control problems, valve setting parameters, temperature loss due to insulation in pipes, etc. Effective leakage detection helps to maximize efficiency of a power station by improving thermal performance and mitigating energy losses from leaks.

[0005] Accordingly, it would be useful to provide improved techniques for monitoring thermal performance in power plants.SUMMARY

[0006] In some aspects, the present disclosure describes a self-powered temperature measurement device for monitoring thermal performance of a pipe of a thermoelectric generator, comprising: a temperature sensor coupled to an external surface of the pipe; a thermoelectric generator (TEG) for harvesting power from a temperature gradient between heat on the external surface and an ambient temperature; a processor for determining a temperature measurement, based on an input from the temperature sensor; and a wireless transmitter for transmitting temperature data from the device to the processor.

[0007] In some embodiments, the power is used to run the temperature sensor and the wireless transmitter.

[0008] In some embodiments of the device, the temperature sensor is a resistance temperature detector (RTD), a negative temperature coefficient (NTC) thermistor or a thermocouple.

[0009] In some embodiments of the device, a thermal diffuser is disposed between the temperature sensor and the TEG.

[0010] In some embodiments of the device the thermal diffuser is a printed circuit board (PCB).

[0011] In some embodiments of the device, a heat dissipater iscoupled to an external side of the TEG.

[0012] In some embodiments of the device a vibration sensor is provided and the wireless transmitter transmits vibration data from the vibration sensor to the processor, and the processor correlates the vibration data with the temperature measurement.

[0013] In an embodiment of the devicethe vibration sensor is a three axis accelerometer.

[0014] In some embodiments of the device a lower extruded portion is in abutment with the external surface of the pipe, and the lower extruded portion houses the temperature sensor.

[0015] In an embodiment of the device, the lower extruded portion is shaped to conform with the curvature of the pipe.

[0016] In an embodiment of the device, the lower extruded portion comprises aluminum.

[0017] In and embodient of the device there is provided a wireless communications module for communicating with a gateway.

[0018] In an embodiment of the device, the communications module includes a Bluetooth interface for transmitting MQTT messages including temperature measurements to the gateway at fixed intervals.

[0019] In an embodiment of the device the communications module includes a Bluetooth interface for transmitting MQTT messages including temperature measurements to the gateway, responsive to a trigger condition.

[0020] In some aspects, the present disclosure describes a system for monitoring thermal performance of a pipe of a thermoelectric generator. The system includes: the device according to any of the previous example aspects of the device and a clamp securing the temperature measurement device to a pipe.

[0021] In an embodiment of the system the clamp is a hose clamp sized to fit around the circumference of the pipe and the temperature measurement device when the temperature measurement device is flush to the pipe.

[0022] In some embodiments, the present disclosure describes a system for monitoring thermal performance of a pipe of a thermoelectric generator. The system includes: the device according to any of the previous example aspects of the device and a vibration sensor transmitting data through the wireless transmitter.

[0023] In some aspects, the present disclosure describes a first method to monitor a temperature of a pipe of a thermoelectric generator. The first method includes a number of steps, including: coupling a temperature sensor and a thermoelectric generator (TEG) to an external surface of the pipe; harvesting power from a temperature gradient between heat on the external surface and an ambient temperature using the TEG; using said power to run the temperature sensor and a wireless transmitter; collecting temperature data using said temperature sensor; transmitting said temperature data to a processor through the wireless transmitter; and monitoring said temperature using said processor.

[0024] In an embodiment of the first method, the temperature sensor and TEG are part of the same device.

[0025] In any of the embodiments of the first method the temperature sensor is a resistance temperature detector (RTD), a negative temperature coefficient (NTC) thermistor or a thermocouple.

[0026] In any of the embodiments of the first method a thermal diffuser is disposed between the temperature sensor and the TEG.

[0027] In an embodiment of the first method the thermal diffuser is a printed circuit board (PCB).

[0028] In any of the embodiments of the first method a heat dissipater is coupled to an external side of the TEG.

[0029] In any of the embodiments of the first method, the method also provides for transmitting vibration data regarding a pipe of a thermoelectric generator from a vibration sensor to the processor and correlating the vibration data with the temperature data.

[0030] In any of the embodiments of the first method the method includes using a communications module which includes a Bluetooth interface for transmitting MQTT messages including temperature measurements to the gateway at fixed intervals.

[0031] In an embodiment of the first method the communications module includes a Bluetooth interface for transmitting MQTT messages including temperature measurements to the gateway, responsive to a trigger condition.

[0032] In some aspects, the present disclosure describes a second method. The second method includes a number of steps, including: transmitting vibration data regarding a pipe of a thermoelectric generator from a vibration sensor to the processor; transmitting temperature data regarding a pipe of a thermoelectric generator from a temperature sensor to the processor; and correlating the vibration data with the temperature data.BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Reference will now be made, by way of example, to the accompanying drawings which show example implementations of the present application, and in which:

[0034] FIG. 1 is a lengthwise cross-sectional view of a segment of instrumented pipe of a steam flow system, in accordance with examples of the present disclosure;

[0035] FIG. 2 shows an example thermal performance monitoring system for monitoring thermal performance in an industrial environment, in accordance with examples of the present disclosure;

[0036] FIG. 3A is a block diagram of an example hardware structure of the self-powered temperature sensing device suitable for implementation of examples described herein;

[0037] FIG. 3B is a schematic diagram of example components of the wireless module, in accordance with examples of the present disclosure;

[0038] FIG. 4 is an elevational and perspective cross-sectional diagram of an example temperature measurement device, in accordance with examples of the present disclosure;

[0039] FIG. 5 is a perspective diagram of an example thermoelectric generator (TEG) of the temperature sensing device of FIG. 4, in accordance with implementations of the present disclosure;

[0040] FIG. 6 is an elevational cross-sectional diagram of an example temperature measurement device securely installed on an insulated pipe using a fastener, in accordance with examples of the present disclosure;

[0041] FIG. 7 is a flowchart showing operations of a method for monitoring a temperature of a pipe of a thermoelectric generator, in accordance with examples of the present disclosure.

[0042] FIG. 8 is a block diagram of an example hardware structure of a server that is suitable for implementing example embodiments.

[0043] Similar reference numerals have been used in different figures to denote similar components.DESCRIPTION OF EXAMPLE IMPLEMENTATIONS

[0044] The following describes example technical solutions of this disclosure with reference to accompanying figures.

[0045] Current methods to diagnose leakage events typically rely on thermography measurement in critical locations in a power plant, which can be costly to implement. For example, instrumentation locations may require travel to pipe or valve locations by site workers, which is labor intensive and time consuming. In some examples, access to pipe or valve locations may be difficult, requiring scaffolding or a scissor lift to access, while some pipe or valve locationsmay be in inaccessible areas. Further, conventional thermography devices used for obtaining thermography measurements (e.g., using an infrared (IR.) thermometer or a laser thermometer, among other possibilities) are limited to obtaining a discrete temperature measurement at a point in time, rather than a continuous stream of temperature measurements for earlier detection of leaks or other issues. The accuracy of conventional thermography devices is also important to consider, as conventional thermography devices can perform with varying accuracy, where accuracy may be influenced by environmental factors such as ambient temperature, humidity and air movement, or operational factors such as the distance or angle of placement, etc. While the use of wireless devices for instrumentation in industrial environments has reduced the need for human intervention (e.g., associated with manually traveling to each instrument location for acquiring temperature or other measurements), many of these wireless devices are battery powered and still require physical access by maintenance staff, such as for replacing batteries.. For scenarios where hundreds of instruments are installed in a power plant, this represents considerable time and effort by maintenance staff.

[0046] In some embodiments, the present disclosure describes examples that address some or all of the above drawbacks of existing techniques for monitoring thermal performance and detecting leakage in a steam flow system.

[0047] FIG. 1 shows a cross-sectional view of a segment of instrumented pipe of a steam flow system, for example, where the pipe is instrumented with a self- powered temperature sensing device 100, in accordance with examples of the present disclosure. In some embodiments the self-powered temperature sensing device 100 may include a temperature sensing unit 400 and a wireless module 300. In examples, an internal cavity 110 of the pipe may convey steam or water vapor, among other possibilities. In this regard, depending on a temperature of the steam or water vapor flowing in the pipe, an exterior surface of a pipe wall 115 may vary in temperature, for example, ranging from -50°C to 260°C or greater. In examples, for minimizing heat loss through the pipe wall 115, the pipe may be surrounded by insulation 120.

[0048] In examples, in instrumenting the pipe, a section of the insulation 120 must be removed to accommodate the temperature sensing device unit 400 (as described with respect to FIG. 4). In examples, removing a section of the insulation 120 enables a temperature sensing surface of the temperature measurement unit 400 to contact the exterior surface of the pipe wall 115, for measuring a temperature of the pipe at a specific location within the steam flow system. In examples, the temperature sensing device unit 400 may be in communication with a wireless module 300 (as described with respect to FIG. 3 below) including an antenna 310, for transmitting data, such as the measured temperature of the pipe (among other data) to a central computing system. For example, wireless module 300 may include sensors, such as vibration monitoring sensors, for example, for measuring vibrations 130 associated with the pipe, or other sensors such as temperature sensors, humidity sensors etc.. The vibration monitoring sensor may be a 3-axis accelerometer. The vibration monitoring sensor in conjunction with a temperature sensor enables better interpretation of data regarding thermal performance of the pipes and identifying any problems with pipes. Although temperature sensing unit 400 and wireless module 300 are shown as separate components, it is understood that temperature sensing unit 400 and wireless module 300 could be integrated into a single component.

[0049] FIG. 2 shows an example thermal performance monitoring system 200 for monitoring thermal performance in an industrial environment, such as a power plant. The thermal performance monitoring system 200 is an illustrative example of a system to which the systems, methods, and processor-readable media described herein can be applied, in accordance with examples of the present disclosure. In examples, the thermal performance monitoring system 200 may include a number of loT devices distributed in an loT network. For example, a plurality of stations, each instrumented with respective self-powered temperature sensing devices (e.g., 100A, 100B ... 100N), including respective temperature sensing units (e.g., 400A, 400B ... 400N) and wireless modules (e.g., 300A, 300B ... 300N) may communicate with a central computing system via a wireless gateway 202. In some embodiments, for example, the plurality of stations may include hundreds ofremote stations in various locations of the power plant. In examples, the gateway 202 may be connected to loT or cloud-based services (e.g., a condition monitoring system, among other possibilities), for example, via a network 206 (such as a local area network (LAN), or a wireless network), for enabling data transmitted from each station to be processed and / or stored in a cloud platform (e.g., using server 208 and database 210), or for enabling a user 204 to interact with an electronic device for accessing the processed and / or stored data in the cloud platform, among other possibilities. In examples, the server 208 and database 210 may represent a distributed computing system including multiple devices (such as a cloud computing platform) or a virtual machine running on one or more devices in mutual communication over a network.

[0050] In some embodiments, for example, the processed and / or stored data may be accessed by the condition monitoring system, for example, via a query to the database 210, for determining an efficiency of the power plant. In other examples, the condition monitoring system may be configured to detect a status of the self-powered temperature sensing device 100, where the status of the self- powered temperature sensing device 100 may be related to a power status (e.g. low battery), a communications status (e.g. low signal) or a status of the self- powered temperature sensing device 100 (e.g. a damaged sensor). In some examples, the condition monitoring system can be configured to generate an alert, for example, based on a predetermined threshold value, among other possibilities. In some examples, the condition monitoring system may be integrated into a software- based Supervisory Control And Data Acquisition (SCADA) system or other cloud-based loT monitoring services (e.g., PI Historian™, Azure™, AWS™, etc.) for the power plant. For example, the condition monitoring system may incorporate a virtual representation of each physical asset or loT device (e.g., a digital twin) in the loT network. In examples, the condition monitoring system may receive data corresponding to the plurality of self-powered temperature sensing devices 100 and may update each respective digital twin with the received data, for monitoring the thermal performance of the power plant.

[0051] In some embodiments, for example, although only one gateway 202 is shown, it is understood that there may be more than one gateway 202 in a distributed thermal performance monitoring system 200 for receiving data from the plurality of self-powered temperature sensing devices 100. In examples, the gateway 202 may be a Message Queuing Telemetry Transport (MQTT) gateway, for example, for receiving MQTT transmissions from each self-powered temperature sensing device 100. In examples, the gateway 202 can include a communications module, a power module and a microprocessor for packaging the received data (among other data) from each self-powered temperature sensing devices 100, prior to sending the data to the server 208. In examples, the gateway 202 may include a Bluetooth™ interface for communicating with each of the plurality of self-powered temperature sensing devices 100, among other possibilities. Advantageously, using a Bluetooth™ interface for communicating with each of the plurality of self-powered temperature sensing devices 100 ensures that power consumption of the gateway 202 is minimal. In some embodiments, for example, the microprocessor may include an edge logic engine that can use edge computing to pre-process the temperature data, thereby reducing the amount of data being sent to the server 208, streamlining resources and reducing computing time and energy at the server 208.

[0052] FIG. 3A is a block diagram of an example hardware structure of the self-powered temperature sensing device 100, that is suitable for implementing example embodiments. The self-powered temperature sensing device 100 includes a temperature sensing unit 400 and a wireless module 300. The temperature sensing unit 400 (described with respect to FIG. 4 below) includes a temperature sensor 420 and a thermoelectric generator (TEG) 440. The wireless module 300 (described in further detail with respect to FIG. 3B below) includes a microprocessor unit (MCU) 302, a power supply 320 and one or more sensors 330. In examples, the MCU comprises at least one processor 304 and may include one or more memories 306 (individually or collectively referred to as "memory 306"), which may include a volatile or non-volatile memory storing instructions for execution by the processor 304, such as for implementing any of the methods ofthe examples and example embodiments. The MCU 302 may also include a wireless interface 308 (for wireless communication over a network). The wireless interface 308 can include wireless links (e.g., for cooperating with one or more antennas 310). In some examples, the wireless module 300 may also include one or more electronic storage units (not shown). In some examples, one or more data sets and / or modules may be provided by an external memory (e.g., an external drive in wired or wireless communication with the wireless module 300). Although FIG. 3A shows a single instance of each component, there can be multiple instances of each component.

[0053] FIG. 3B is a schematic diagram of example components of the wireless module 300, in accordance with examples of the present disclosure. In examples, the wireless module 300 may enable harvesting energy (e.g., thermal energy) from the TEG 440, for powering the temperature sensing unit 400 and wireless module 300 and may store the harvested thermal energy by charging a power supply 320 (e.g., battery, supercapacitor). In examples, the wireless module 300 may receive pipe temperature measurements from the temperature sensor 420, and may obtain other measurements using onboard sensors 330 (such as vibration sensors and / or ambient temperature or humidity sensors etc.), for monitoring system health, and transmitting the acquired data to a central computing system.

[0054] In examples, the wireless module 300 may include a number of components, including an input protection circuit 312 (e.g., including an electrostatic discharge (ESD) and reverse polarity protector and over voltage (OV) protection), a power supply 320 such as a battery 322 (e.g., a small 250-1000 mAh battery) or a supercapacitor, and a harvest boost converter 324 for charging the power source. The MCU 302 (e.g., an ARM®-type MCU) may control the operation of the wireless module 300, for example, facilitating communication (e.g., via Bluetooth™ low energy (BLE) communication, among other possibilities) with the temperature measurement unit 400, various sensors 330 of the wireless module 300 and the gateway 202. In examples, MCU 302 may receive data from the temperature sensor 420, a vibration sensor (e.g., a 3-axis accelerometer 332 fordetecting vibrations in the pipe) and / or an ambient temperature / humidity sensor 334 (e.g., for measuring an ambient temperature and / or a humidity of the environment surrounding the pipe). In examples, the wireless module 300 may also include an analog-to-digital converter (ADC) 332, for interfacing with the temperature sensor 420 and / or other sensors 330. In examples, the MCU 302 may detect an abnormality in the temperature of the pipe, in a vibration level in the pipe, or in the ambient temperature or the humidity of the surroundings and may report the abnormality to a condition monitoring system. Ambient temperatures outside of threshold operating temperature ranges (e.g., between 20°C and 45°C, among other possibilities) or ambient moisture / humidity can be detrimental to the performance of the wireless module 600, for example, where moisture may cause rusting or other corrosion. In examples, vibrations in the pipe may be detected based on frequency analysis of the accelerometer data, for example, using a FFT- based (Fast Fourier Transform) algorithm. Thus, a three-axis accelerometer 632 can be used to detect the vibration of the pipes, where the MCU 302 can monitor the scanning of the vibration levels of the pipe. In other examples, system health monitoring processes may trigger the MCU 302 to send alerts to the condition monitoring system in response to a number of conditions being met, for example, responsive to the pipe temperature exceeding a predefined threshold, vibration measurements exceeding predefined thresholds, communication and sensor faults, low battery, BLE communication failure with the gateway 202, or the ambient room temperature or humidity measurements exceeding predefined thresholds, among other possibilities. In examples, power-on reset circuitry 314 may be included to provide an appropriate reset signal for the MCU 302, and an input capacitor 316 may be used to provide stability for the harvest boost converter 324 as well as to harvest energy from the TEG 440. Further, the wireless module 300 may further include charger detect circuitry 626 for identifying or detecting the type of battery charger or charging port and enabling the MCU 302 to determine an amount of power that is available for charging, and a power supervision circuit 628 associated with the battery 622.

[0055] FIG. 4 is a schematic diagram of an example temperature measurement unit 400, in accordance with examples of the present disclosure.

[0056] In some embodiments, for example, the temperature measurement unit 400 includes a lower portion 410 configured to house the temperature sensor 420 for measuring the temperature of the pipe, and an upper portion 450 configured for heat dissipation. In examples, the lower portion 410 and the upper portion 450 may be extruded portions, for example, comprising a conductive material such as aluminum, among other possibilities. In examples, the temperature measurement unit 400 may include the thermoelectric generator (TEG) 440 for harvesting energy from a temperature differential.

[0057] The use of a high heat dissipating metal as the framework for holding the temperature sensor 420 and the TEG 440 is particularly beneficial. For example, incorporation of a heat dissipater (e.g., plurality of heat dissipaters 455) into the temperature measurement unit 400 may allow the TEG 440 to operate in environments that represent temperatures above an operating limit of the TEG 440. For example, when the temperature of the pipe (e.g., 275°C) being measured exceeds an operating limit of the TEG 440 (e.g., 230°C), the heat dissipaters 455 may effectively dissipate heat such that the TEG 440 may still operate within recommended temperature limits. It is understood that the operating temperatures provided are for exemplary purposes only, and that the operating limit for the TEG 440 may change over time with advancements in technology), While any high heat dissipating metal may be suitable, aluminum is particularly useful.

[0058] In examples, the temperature sensor 420 may be a resistance temperature detector (RTD) (such as a three-wire RTD), or other temperature sensors may be used, such as a negative temperature coefficient (NTC) thermistor or a thermocouple, among other possibilities. In exemplary embodiments where the temperature sensor 420 is an RTD, the RTD may be inserted into an aperture in the lower portion 410 of the temperature measurement unit 400. In examples, thermal grease 460 (e.g., paste) may be applied to the contact surface of the RTD and the aperture, for facilitating the thermal bonding between the RTD and the lowerportion 410. While the aperture is shown extending parallel to an axis of the pipe, it is understood that the aperture may be in other configurations. In examples, the RTD may be positioned in the center of the lower portion 410, for example, for improving the accuracy of temperature measurement for the pipe.

[0059] In examples, the temperature measurement unit 400 is configured to measure the temperature of the pipe when a contact surface of the lower portion 410 is in abutment with an external surface of the pipe (e.g., outer surface of pipe wall 115). In examples, the contact surface may be configured with a concave shape for seamlessly abutting the external surface of the pipe, for example, to accommodate for a bend radius of the steam pipe. In examples, the size and shape of the components of the temperature measurement unit 400 (e.g., including the lower portion 410) may be configured for any size pipe. In examples, thermal grease 460 (e.g., paste) may be applied to the contact surface of the lower portion 410 and the pipe wall 115, for facilitating the thermal bonding between the pipe and the temperature measurement unit 400.

[0060] In examples, when hot steam is flowing through the pipe, the pipe can become very hot, for example, reaching temperatures up to 260°C or higher, and heat from the pipe may be conducted through the temperature measurement unit 400, for example, from the lower portion 410 to the upper portion 450. In examples, heat conducted through the temperature measurement device 400 may be dissipated at the upper portion 450, for example, via a plurality of fins or other heat dissipaters 455. In this regard, a considerable heat differential may be created across the temperature measurement unit 400, for example, from the lower portion 410 to the upper portion 450.

[0061] In some embodiments, for example, the temperature measurement unit 400 may be a self-powered device, for example, the heat differential may be harvested for powering the temperature measurement unit 400. In examples, the TEG 440 may be integrated into the temperature measurement unit 400, for example, disposed between the lower portion 410 and the upper portion 450, as described with respect to FIG. 5.

[0062] FIG. 5 is a schematic diagram of an example TEG 440 of the temperature sensing unit 400 of FIG. 4, in accordance with implementations of the present disclosure. A TEG 440 is a device that converts heat into electrical energy, for example, generating a voltage in response to a temperature gradient, and enabling current to flow in a circuit. In examples, the TEG 440 may comprise thermoelectric materials, for example, having high electrical conductivity and low thermal conductivity, such that when one side of the TEG 440 is exposed to a high temperature (e.g., a hot side 442) and the opposite side of the TEG 440 remains cool (e.g., a cold side 444), a voltage is generated in response to and / or proportional to the temperature differential.

[0063] In examples, the TEG 440 may be configured in the temperature sensing unit 400 such that the hot side 442 faces the external surface of the pipe, and the cold side 444 faces away from the pipe (and towards the heat dissipating upper portion 450). In examples, the heat dissipation properties of the upper portion 450 may assist in improving the performance of the TEG 440, for example, by helping to keep the cold side 444 cool. The higher the temperature differential between the hot side 442 and the cold side 444, the greater the voltage generated by the TEG 440.

[0064] In examples, the TEG 440 may be used to power the temperature measurement unit 400 by charging a battery 322 in the wireless module 300 (as described previously with respect to FIG. 3), for example, where energy may be stored in the battery 322 during periods of high temperature differential, and where the temperature measurement unit 400 may draw current from the charged battery 322 during periods of low temperature differential (e.g., when the pipe temperature is cool, and no temperature gradient exists).

[0065] Returning to FIG. 4, the TEG 440 may typically be rated for maximum temperatures (e.g., operational limit of exposure on the hot side 442), for example, up to 230°C, among other possibilities. However, in some scenarios, steam pipe temperatures may exceed the temperature rating, for example, rising up to 275°C (e.g., when the steam flowing to through the pipe is saturated steam, among otherpossibilities). To avoid damaging the TEG 440, a thermal diffuser 430 may be integrated into the temperature measurement unit 400, for example, disposed between the lower portion 410 and the TEG 440, for creating a thermal resistance or insulation between the lower portion 410 and the hot side 442 of the TEG 440. In some embodiments, for example, the thermal diffuser 430 may be an ultra-thin PCB or a fiberglass, among other possibilities, for mitigating risk to the hot side 442 of the TEG 440 from temperatures higher than the rated temperatures, that could damage the TEG 440. In examples, a desired thickness of the thermal diffuser 430 may be determined by performing thermal analysis and modeling the projected temperature reduction to the hot side 442 of the TEG 440, caused by the thermal diffuser 430, based on factors such as pipe dimensions, pipe curvature, contact surface area between the pipe and the temperature measurement unit 400, thickness of the lower portion 410, thermal conductivity of various materials (e.g., lower portion, insulator etc.), maximum rated temperature for the TEG 440 etc. In examples, thermal grease 460 (e.g., paste) may be applied to the contact surfaces of the lower portion 410, the thermal diffuser 430, the TEG 440 and the upper portion 450, for facilitating the thermal bonding between the various components.

[0066] The use of an thermal diffuser or insulator between an upper framework holding the TEG 440 and a lower framework holding the temperature sensor 420 allows the TEG 440 to operate when the pipe being measured is at a temperature that exceeds the operating limits of the TEG 440.

[0067] FIG. 6 is a schematic diagram of an example temperature measurement unit 400 securely installed on an insulated pipe using a fastener 600, in accordance with examples of the present disclosure. In some embodiments, for example, the fastener 600 may be a hose clamp, or other fasteners may be used. In examples, a portion of the pipe insulation 120 may be removed to facilitate the mounting of the temperature sensing unit 400 on the exterior surface of the pipe wall 115, for example, as shown with respect to FIG. 4. In examples, the fastener 600 may encircle the pipe and may be coupled to the temperature sensing unit 400, such that when the fastener 600 is tightened, the fastener 600 may cause acompressive force to be exerted on the exterior surface of the pipe wall 115 by the temperature sensing unit 400, for example, for ensuring compressive contact between the lower portion 410 and the pipe. In examples, the wireless module 300 may be secured to the fastener 600, as shown, or the wireless module 300 may be secured to the pipe by other means. In examples, once the temperature sensing unit 400 is securely fixed to the pipe, a temperature of the pipe may be determined, among other data, such as a pipe vibration 130.

[0068] Fastener 600 provides several advantages over the prior art. For example, it is easier to remove and replace than fasteners of the prior art, which are typically a hardened epoxy resin. It is also less likely to fail (i.e. allow the temperature sensing unit 400 to come loose.

[0069] FIG. 7 is a flowchart showing operations of a method 700 for monitoring a temperature of a pipe of a thermoelectric generator, in accordance with examples of the present disclosure. The method 700 can be performed in the context of the components of the thermal performance monitoring system 200 shown in FIG. 2 in some embodiments.

[0070] Method 700 begins at step 702 in which a temperature sensor 420 and a TEG 440 are coupled to an external surface of a pipe (e.g., pipe wall 115). In some embodiments, for example, the pipe may be surrounded by an insulative material, and a portion of the insulation may be removed to facilitate the coupling of the temperature sensor 420 and the TEG 440 on the pipe wall 115.

[0071] At step 704, power is harvested from a temperature gradient between heat on the external surface and an ambient temperature in the environment surrounding the pipe, using the TEG 440. For example, when one side of the TEG 440 is exposed to a high temperature and the opposite side of the TEG 440 remains cool, a voltage may be generated in response to and / or proportional to the temperature differential. In examples, the energy may be stored, for example, in a rechargeable battery 322 during periods of high temperature differential, such that current may be drawn from the charged battery 322 during periods of low temperature differential.

[0072] At step 706, said power is used to run the temperature sensor 420 and a wireless transmitter. For example, during periods of high temperature differential, the TEG 440 may provide power to the temperature sensor 420 and a wireless transmitter, while in periods of low temperature differential, the temperature sensor 420 and wireless transmitter may be powered by rechargeable battery 322.

[0073] At step 708, temperature data is collected using said temperature sensor. For example, a temperature of the pipe may be measured using the temperature sensor 420. In examples, the temperature sensor 420 may be a RTD (such as a three-wire RTD), a NTC thermistor or a thermocouple, among other possibilities.

[0074] At step 710, said temperature data is transmitted to a processor through the wireless transmitter. In examples, a wireless transmitter may transmit the temperature data to a central computing system (e.g., a cloud platform) via a gateway 202 that may be connected to loT or cloud-based services (e.g., a condition monitoring system, among other possibilities), for example, via a network 206.

[0075] At step 712, said temperature data is monitored using said processor. For example, the temperature data may be processed and / or stored in the cloud platform (e.g., using server 208 and database 210) and monitored by a condition monitoring system (e.g., operating in the cloud platform). In some examples, the condition monitoring system can be configured to generate an alert, for example, based on a predetermined temperature threshold value, among other possibilities.

[0076] FIG. 8 is a block diagram of an example hardware structure of a server 208 that is suitable for implementing example embodiments. For example, the server 208 may represent a single electronic device or the server 208 may be a component of a distributed computing system (such as a cloud computing platform), for operating a cloud-based loT network, including the condition monitoring system. Other examples suitable for implementations described in the present disclosure can be used, which can include components different from thosediscussed below. Although FIG. 8 shows a single instance of each component, there can be multiple instances of each component in the server 208.

[0077] The server 208 includes at least one processor 802, such as a central processing unit, a microprocessor, a digital signal processor, an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), a dedicated logic circuitry, a dedicated artificial intelligence processor unit, a graphics processing unit (GPU), a tensor processing unit (TPU), a neural processing unit (NPU), a hardware accelerator, or combinations thereof.

[0078] The server 208 can include one or more network interfaces (collectively referred to as network interface 806) for wired or wireless communication over a network. The network interface 806 can include wired links (e.g., Ethernet cable) and / or wireless links (e.g., one or more antennas). The computing system 300 can communicate with one or more user devices (such as user workstation computers) via the network interface 806.

[0079] The server 208 may include an input / output (I / O) interface 808, which may enable interfacing with an optional input device (e.g., a keyboard, a mouse, a microphone, a camera, a scanner, a touchscreen, and / or a keypad) and / or an optional output device (e.g., a display, a speaker and / or a printer). In other example embodiments, there may not be any input device and output device, in which case the I / O interface 808 may not be needed.

[0080] The server 208 may include one or more memories 804 (individually or collectively referred to as "memory 804"), which may include a volatile or nonvolatile memory (e.g., a flash memory, a random-access memory (RAM), and / or a read-only memory (ROM)). The non-transitory memory 804 may store instructions for execution by the processor 802, such as to carry out example embodiments. For example, the memory 804 may store instructions for implementing any of the methods of the examples and example embodiments. The memory 804 may include other software instructions, such as for implementing an operating system (OS) and other applications / functions.

[0081] In some examples, the server 208 may also include one or more electronic storage units (not shown), such as a solidstate drive, a hard disk drive, a magnetic disk drive and / or an optical disk drive. In some examples, one or more data sets and / or modules may be provided by an external memory (e.g., an external drive in wired or wireless communication with the server 208) or may be provided by a transitory or non-transitory computer-readable medium. Examples of non-transitory computer readable media include a RAM, a ROM, an erasable programmable ROM (EPROM), an electrically erasable programmable ROM (EEPROM), a flash memory, a CD-ROM, or other portable memory storage. The components of the server 208 may communicate with each other via a bus, for example.General

[0082] Although the present disclosure describes functions performed by certain components and physical entities, it should be understood that, in a distributed system, some or all of the processes can be distributed among multiple components and entities, and multiple instances of the processes can be carried out over the distributed system.

[0083] Although the present disclosure describes methods and processes with steps in a certain order, one or more steps of the methods and processes can be omitted or altered as appropriate. One or more steps can take place in an order other than that in which they are described, as appropriate.

[0084] Although the present disclosure is described, at least in part, in terms of methods, a person of ordinary skill in the art will understand that the present disclosure is also directed to the various components for performing at least some of the aspects and features of the described methods, either by way of hardware components, software or any combination of the two. Accordingly, the technical solution of the present disclosure can be embodied in the form of a software product. A suitable software product can be stored in a pre-recorded storagedevice, for example. The software product includes instructions tangibly stored thereon that enable a processing device (e.g., a personal computer, a server, or a network device) to execute examples of the methods disclosed herein. In general, the software improves the operation of the hardware in one or more ways.

[0085] The present disclosure can be embodied in other specific forms without departing from the subject matter of the claims. The described example implementations are to be considered in all respects as being only illustrative and not restrictive. Selected features from one or more of the above-described implementations can be combined to create alternative implementations not explicitly described, features suitable for such combinations being understood within the scope of this disclosure.

[0086] All values and sub-ranges within disclosed ranges are also disclosed. Also, although the systems, devices and processes disclosed and shown herein can include a specific number of elements / components, the systems, devices and assemblies could be modified to include additional or fewer of such elements / components. For example, although any of the elements / components disclosed can be referenced as being singular (e.g., a well), the implementations disclosed herein could be modified to include a plurality of such elements / components (e.g., an array of wells). The subject matter described herein intends to cover and embrace all suitable changes in technology.

Claims

WE CLAIM:

1. A self-powered temperature measurement device for monitoring thermal performance of a pipe of a thermoelectric generator, comprising: a temperature sensor coupled to an external surface of the pipe; a thermoelectric generator (TEG) for harvesting power from a temperature gradient between heat on the external surface and an ambient temperature; a processor for determining a temperature measurement, based on an input from the temperature sensor; and a wireless transmitter for transmitting temperature data from the device to the processor.

2. The device of claim 1, wherein the power is used to run the temperature sensor and the wireless transmitter.

3. The device of claim 1 or 2, wherein the temperature sensor is a resistance temperature detector (RTD), a negative temperature coefficient (NTC) thermistor or a thermocouple.

4. The device of claims 1 to 3, further comprising a thermal diffuser disposed between the temperature sensor and the TEG.

5. The device of claim 4 wherein the thermal diffuser is a printed circuit board (PCB).

6. The device of claims 1 to 5, further comprising a heat dissipater coupled to an external side of the TEG.

7. The device of claims 1 to 6, further comprising: a vibration sensor, wherein the wireless transmitter transmits vibration data from the vibration sensor to the processor,wherein the processor correlates the vibration data with the temperature measurement.

8. The device of claim 7, wherein the vibration sensor is a three axis accelerometer.

9. The device of claims 1 to 8, further comprising: a lower extruded portion in abutment with the external surface of the pipe, the lower extruded portion housing the temperature sensor.

10. The device of claim 9 wherein the lower extruded portion is shaped to conform with the curvature of the pipe.

11. The device of claims 9 to 10, wherein the lower extruded portion comprises aluminum.

14. The device of claims 1 to 13, further comprising: a wireless communications module, for communicating with a gateway.

15. The device of claim 14, wherein the communications module includes a Bluetooth interface for transmitting MQTT messages including temperature measurements to the gateway at fixed intervals.

16. The device of claim 14 or 15, wherein the communications module includes a Bluetooth interface for transmitting MQTT messages including temperature measurements to the gateway, responsive to a trigger condition.

17. A temperature measurement system for monitoring thermal performance of a pipe of a thermoelectric generator comprising: the device of any of claims 1 to 16 and a clamp securing the temperature measurement device to a pipe.

18. The temperature measurement system of claim 17 wherein the clamp is a hose clamp sized to fit around the circumference of the pipe and the temperature measurement device when the temperature measurement device is flush to the pipe.

19. A temperature measurement system for monitoring thermal performance of a pipe of a thermoelectric generator comprising: the device of claims 1 to 16; and a vibration sensor transmitting data through the wireless transmitter.

20. A method of monitoring a temperature of a pipe of a thermoelectric generator comprising: coupling a temperature sensor and a thermoelectric generator (TEG) to an external surface of the pipe; harvesting power from a temperature gradient between heat on the external surface and an ambient temperature using the TEG; using said power to run the temperature sensor and a wireless transmitter; collecting temperature data using said temperature sensor; transmitting said temperature data to a processor through the wireless transmitter; and monitoring said temperature using said processor.

21. The method of claim 20 wherein said temperature sensor and TEG are part of the same device.

22. The method of claim 20 or 21, wherein the temperature sensor is a resistance temperature detector (RTD), a negative temperature coefficient (NTC) thermistor or a thermocouple.

23. The method of claims 21 to 22, wherein a thermal diffuser is disposed between the temperature sensor and the TEG.

24. The method of claim 23 wherein the thermal diffuser is a printed circuit board (PCB).

25. The method of claims 20 to 24, further comprising a heat dissipater coupled to an external side of the TEG.

26. The method of claims 20 to 25, further comprising: transmitting vibration data regarding a pipe of a thermoelectric generator from a vibration sensor to the processor; and correlating the vibration data with the temperature data.

27. The method of claims 20 to 26, further comprising using a communications module which includes a Bluetooth interface for transmitting MQTT messages including temperature measurements to the gateway at fixed intervals.

28. The method of claim 27, wherein the communications module includes a Bluetooth interface for transmitting MQTT messages including temperature measurements to the gateway, responsive to a trigger condition.

29. A method comprising: transmitting vibration data regarding a pipe of a thermoelectric generator from a vibration sensor to the processor; transmitting temperature data regarding the pipe of the thermoelectric generator from a temperature sensor to the processor; and correlating the vibration data with the temperature data.

Images