Power consumption measurement endpoint

Abstract

A power consumption measurement endpoint comprising a local clock and a clock compensation module, wherein the clock compensation module is configured to receive a plurality of reference clock time updates output by a reference clock, record the time of the local clock at which the plurality of reference clock time updates were received, and determine an approximation function of the error progression between the local clock and the reference clock, and further configured to acquire the time of the local clock, determine the error between the local clock and the reference clock using the time of the local clock and the approximation function, calculate a compensated time using (i) the time of the local clock and (ii) the error between the local clock and the reference clock, and send at least one clock configuration message to the local clock based on the compensated time, and the local clock outputs a time update based on the clock configuration message.

Description

[Technical Field]

[0001] Disclosure technology This disclosure relates to power consumption measurement endpoints (e.g., electric meters) for measuring power consumption in residential and commercial facilities. In particular, this disclosure relates to power consumption measurement endpoints having a clock compensation module. [Background technology]

[0002] background A power consumption measurement endpoint (for example, an electric meter, also known in the art as a power meter, motor meter, or electric meter) is a device that measures the amount of electricity consumed by one or more electrically driven devices over a period of time, such as in a residential or commercial building.

[0003] Electricity meters are typically installed in facilities for billing and monitoring consumption. In some cases, electricity meters may be manually read periodically to determine the level of electricity consumption. In other cases, advanced electricity meters, known in the art as “smart meters,” may be configured to communicate with utilities (e.g., wirelessly) to provide electricity consumption information and / or receive billing information and / or control signals.

[0004] Electricity meters use time for monitoring usage and for timestamping diagnostic and billing-related events. The accuracy of the clock maintained by the clock source within the meter is susceptible to drift over time because the clock source is typically a crystal or crystal oscillator, which, in addition to its inherent error from the nominal value, is also subject to errors due to temperature changes and component aging.

[0005] Previously, electric meters used the power grid frequency as a time source to periodically calculate and compensate for errors in their local clock. This method has been widely abandoned as power grid operators have ceased to adhere to the practice of strictly synchronizing the power grid frequency with an accurate reference time source. [Overview of the project] [Means for solving the problem]

[0006] overview The inventors identified the need for a power consumption measurement endpoint that can maintain a more accurate clock over time relative to a reference clock.

[0007] When a time adjustment occurs, the electric meter corrects the time, marking the load profile section as longer or shorter based on the direction of the time adjustment, ending the current demand section and starting a new one, ensuring that the artificially long section does not cause a peak demand; however, this operation may prevent the recording of a true new peak. Since marking load profile sections and potentially missed peak demand values ​​affect utilities, there is merit in minimizing the frequency of these occurrences. Furthermore, if the accuracy of timestamps associated with diagnostic data and other event data becomes more stringent, there is also merit in the usefulness of that data.

[0008] According to a first aspect of the present disclosure, a power consumption measurement endpoint is provided, the power consumption measurement endpoint comprising a local clock and a clock compensation module, the clock compensation module configured to receive a plurality of reference clock time updates output by an external reference clock of the power consumption measurement endpoint, each of the plurality of reference clock time updates records the time of the local clock that has been received, and to use the plurality of reference clock time updates and the time of the local clock to determine an approximation function of the progression of the error over time between the local clock and the reference clock, the clock compensation module further configured to perform a local clock update process, the clock compensation module further configured to obtain the time of the local clock, to use the time of the local clock and the approximation function to determine the error between the local clock and the reference clock, to (i) use the time of the local clock and (ii) use the error between the local clock and the reference clock to calculate a compensated time, and to send at least one clock configuration message to the local clock based on the compensated time, the local clock configured to output a time update based on at least one clock configuration message.

[0009] Advantageously, power consumption measurement endpoints can maintain a more accurate local clock.

[0010] Periodic updates of the local clock, performed by applying adjustments based on calculated errors, can lead to zero error between the local clock and the reference clock. This minimizes the amount of clock drift in the meter between reference clock updates and reduces the frequency of reference clock time updates. This directly reduces the amount of network traffic that needs to be consumed by transmitting reference clock time updates. It also reduces the number of network devices that require a reference clock (e.g., GPS modules).

[0011] At least one clock configuration message may contain only a single clock configuration message, and a single clock configuration message may contain compensated time.

[0012] At least one clock configuration message contains only a single clock configuration message, and this single clock configuration message contains an instruction to the local clock to accelerate or decelerate by a time value corresponding to the error between the local clock and the reference clock.

[0013] At least one clock configuration message includes multiple clock configuration messages, and the clock compensation module is configured to send multiple clock configuration messages sequentially, each of which includes an instruction to the local clock to accelerate or decelerate by a time value, and the sum of the time values ​​of each of the multiple clock configuration messages is equal to the error between the local clock and the reference clock.

[0014] A clock compensation module may be configured to receive one or more further reference clock time updates output by a reference clock and to adapt an approximation function using the multiple reference clock time updates and one or more further reference clock time updates.

[0015] A power consumption measurement endpoint may comprise a communication unit configured to receive multiple reference clock time updates and a measurement unit, the measurement unit including a measurement application configured to generate time-based power-related data by (i) relating power-related data associated with power consumed in a power distribution system and (ii) relating it with time updates, and the communication unit may be further configured to communicate the time-based power-related data to one or more external devices.

[0016] The measurement unit may include a local clock and a clock compensation module.

[0017] Alternatively, the communication unit may include a local clock and a clock compensation module.

[0018] The measurement unit is an interface to the power distribution system, where the analog power-related data is associated with the power consumed in the power distribution system, an analog / digital conversion circuit for converting the analog power-related data into digital power-related data, and a processor configured to process the digital power-related data to generate power-related data and supply the power-related data to a measurement application.

[0019] The communication unit may be configured to communicate time-based power-related data to one or more external devices via a mesh-based communication network.

[0020] The clock compensation module may be configured to periodically receive updates to a reference clock time.

[0021] The clock compensation module may be configured to periodically execute a local clock update process.

[0022] According to another aspect of the present disclosure, a mesh-based communication network is provided, the mesh-based communication network comprising the power consumption measurement endpoint described herein and at least one network device, wherein one of the at least one network devices includes a reference clock.

[0023] The network device including the reference clock may be a further power consumption measurement endpoint. Alternatively, the network device including the reference clock may be a server.

[0024] In another aspect of the present disclosure, a method is provided for updating a local clock on a power consumption measurement endpoint, the method being performed by a clock compensation module on the power consumption measurement endpoint, and comprising: receiving a plurality of reference clock time updates output by an external reference clock on the power consumption measurement endpoint; recording the time of the local clock received for each of the plurality of reference clock time updates; determining an approximation function of the time-dependent error between the local clock and the reference clock using the plurality of reference clock time updates and the time of the local clock; and performing a local clock update process, which is performed by: obtaining the time of the local clock; determining the error between the local clock and the reference clock using the time of the local clock and the approximation function; calculating a compensated time using (i) the time of the local clock and (ii) the error between the local clock and the reference clock; and sending at least one clock configuration message to the local clock based on the compensated time.

[0025] According to another aspect of the present disclosure, at least one non-temporary computer-readable storage medium is provided, which includes instructions that, when executed by at least one processor, cause at least one processor to execute one of the methods performed by the clock compensation module described herein.

[0026] Instructions may be provided on one or more carriers. For example, there may be one or more non-temporary memories, such as program memory, such as EEPROM (e.g., flash memory), disk, CD or DVD-ROM, read-only memory (e.g., for firmware), one or more temporary memories (e.g., RAM), and / or data carriers, such as optical or electrical signal carriers. One or more memories may be integrated into the corresponding processing chip and / or separate from the chip. Code (and / or data) for implementing embodiments of the present disclosure may include source, object or executable code, assembly code, code for setting up or controlling an ASIC (Application-Specific Integrated Circuit) or FPGA (Field-Programmable Gate Array), or code in a hardware description language, such as C.

[0027] The above summary is illustrative and intended to be non-limiting. This disclosure includes one or more corresponding aspects, embodiments, or features, either individually or in various combinations, whether they are specifically described (including claimed) in combination or individually. Features defined above in accordance with any aspect of this disclosure, or defined below in relation to any particular embodiment of this disclosure, should be understood as being usable in any other aspect or embodiment, either individually or in combination with any other defined feature, to form further aspects or embodiments of this disclosure.

[0028] Brief explanation of the drawing These and other aspects of the present disclosure are described here merely as examples with reference to the accompanying drawings. [Brief explanation of the drawing]

[0029] [Figure 1] This shows a mesh network. [Figure 2a] A schematic block diagram of a clock compensation module and local clock in one exemplary configuration is shown. [Figure 2b] A schematic block diagram of the clock compensation module and local clock in another exemplary configuration is shown. [Figure 3] A schematic block diagram of a power consumption measurement endpoint according to one embodiment of the present disclosure is shown. [Figure 4] A schematic block diagram of a power consumption measurement endpoint according to another embodiment of the present disclosure is shown. [Figure 5] This flowchart shows the methods that can be performed by the power consumption measurement endpoint. [Figure 6] The waveform of an exemplary linear equation that approximates the error between the local clock and the reference clock is shown. [Figure 7] This is a flowchart of the local clock update process. [Figure 8] This section demonstrates how the use of the local clock's time and approximation functions can be employed to determine the error between the local clock and the reference clock. [Modes for carrying out the invention]

[0030] Detailed description of the drawing Figure 1 shows a mesh network 102 containing multiple power consumption measurement endpoints 106. It should be understood that the number of power consumption measurement endpoints 106 shown in the mesh network 102 is merely an example. The mesh network 102 may be an Advanced Measurement Infrastructure (AMI), a radio frequency (RF) network. Other embodiments can also be implemented outside of the AMI system.

[0031] In one example, a mesh network 102 is associated with a power distribution network to deliver measurements or other data acquired from the distribution network. In this example, multiple power consumption measurement endpoints 106 include electric meters, which are implemented to measure various operating characteristics of the power distribution network and transmit the collected data to a server 104 through the mesh network 102.

[0032] Server 104 receives streams of data or messages from multiple power consumption measurement endpoints 106. Server 104 can process the collected data for various applications, or have the collected data processed by other servers.

[0033] Each power consumption measurement endpoint 106 within the mesh network 102 can communicate with other devices within the mesh network 102 (e.g., server 104 and other power consumption measurement endpoints) via wired and / or wireless communication channels. Similarly, server 104 can communicate with one or more power consumption measurement endpoints 106 via wired and / or wireless communication channels.

[0034] One or more of the multiple power consumption measurement endpoints 106 may include a reference clock 108. This is shown in Figure 1 by a power consumption measurement endpoint 106a that includes a reference clock 108. Alternatively or additionally, a server 104 may include a reference clock 108. The reference clock 108 is configured to provide multiple reference clock time updates in an accurate and stable manner (e.g., periodically).

[0035] According to embodiments of this disclosure, the clock compensation module 206 of the power consumption measurement endpoints 106b to e determines an approximate function of the time-dependent error between the local clock and the reference clock using (i) a plurality of reference clock time updates output by the reference clock 108, and (ii) the time of the local clock 204 at which each of the plurality of reference clock time updates is received. This will be described in more detail below with reference to Figures 5 and 6.

[0036] Next, the clock compensation module 206 of the power consumption measurement endpoints 106b~e performs a local clock update process based on the local clock time and approximation function, and based on the compensated time, it can send at least one clock configuration message to the local clock 204. The at least one clock configuration message configures the local clock 204 to output a time update based on the at least one clock configuration message.

[0037] Figure 2a shows a schematic block diagram of a local clock 204 and a clock compensation module 206 in one exemplary configuration, where the local clock 204 and the clock compensation module 206 are components of a single processor 202, which may be, for example, a microprocessor or microcontroller.

[0038] Figure 2b shows a schematic block diagram of a local clock 204 and a clock compensation module 206 in another exemplary configuration, where the local clock 204 is located outside the processor 222, which also includes the clock compensation module 206. In this exemplary configuration, the local clock 204 may be provided on a dedicated integrated circuit (IC). In this exemplary configuration, the local clock 204 and the clock compensation module 206 may communicate via an I2C or SPI bus, or via a UART.

[0039] In both exemplary configurations, the clock compensation module 206 is configured to receive a reference clock time update output by the reference clock 108. The clock compensation module 206 is also configured to receive a local clock time update from the local clock 204. The clock compensation module 206 is configured to send at least one clock configuration message to the local clock 204. The local clock 204 is configured to receive at least one clock configuration message and output a time update based on at least one clock configuration message.

[0040] The functions of the clock compensation module 206 described herein may be implemented in code (software), which is stored in the memory of a power consumption measurement endpoint having one or more storage media and is configured to run on processors 202, 222 having one or more processing units. Alternatively, some or all of the functions of the clock compensation module 206 may be implemented in dedicated hardware circuitry (e.g., configurable hardware circuitry such as ASICs, simple circuits, gates, logic, and / or FPGAs).

[0041] Figures 3 and 4 are schematic block diagrams of a power consumption measurement endpoint (e.g., one of the power consumption measurement endpoints 106b to e) that does not include the reference clock 108.

[0042] As shown in both Figures 3 and 4, the power consumption measurement endpoint 106 includes a communication unit 302 and a measurement unit 304.

[0043] The communication unit 302 enables wired and / or wireless communication between the power consumption measurement endpoint and other power consumption measurement endpoints and / or the server 104. In particular, the communication unit 302 is configured to receive reference clock time updates output by the reference clock 108 (located outside the power consumption measurement endpoint 106).

[0044] The communication unit 302 may enable receiving radio frequency transmissions from other power consumption measurement endpoints and / or server 104. The communication unit 302 may enable sending radio frequency transmissions to other power consumption measurement endpoints and / or server 104.

[0045] Alternatively or additionally, the communication unit 302 may enable communication with other power consumption measurement endpoints and / or the server 104 via power line communication (PLC) over the power lines of the power distribution network.

[0046] Alternatively or additionally, the communication unit 302 may enable communication with other power consumption measurement endpoints and / or the server 104 by point-to-point wireless (e.g., cellular) communication.

[0047] The measurement unit 304 is configured to receive analog power-related data associated with the power consumed in the distribution network. The power-related data may include measured voltage, current, and / or power signals. In particular, the power-related data may include one or more of the following: (i) a load-side voltage signal indicating the voltage of a load (which may be a residential load such as a house), (ii) a "C phase" current flowing through the load, and (iii) an "A phase" current flowing through the load. The power-related data may also include RMS voltage and / or current signals.

[0048] The measurement unit 304 includes an analog-to-digital converter (ADC) 308 that converts analog power-related data into digital power-related data. The digital power-related data is output by the ADC 308 to a processor (e.g., a digital signal processor) 308, which processes the digital power-related data and is configured to output processed digital power-related data (indicated as "calculated value").

[0049] The measurement unit 304 may further include a serial port 310 for enabling optical communication between the power consumption measurement endpoint and a portable computing device during installation or maintenance procedures (for example, to read billing data, read and change time of use (TOU), reset billing periods, reset registers and profiles, read and change parameters, etc.).

[0050] The measurement unit 304 may further include an input device 312 (e.g., a button) for receiving user input, for example, from a customer or maintenance technician of a public utility.

[0051] The measurement unit 304 may further include a display device (e.g., an LCD display device) 314 for outputting data (e.g., power consumption information).

[0052] As shown in Figures 3 and 4, the measurement unit 304 includes a measurement application 306.

[0053] The measurement application 306 is configured to receive processed digital power-related data and time information from the processor 308 and to generate time-based power-related data using the processed digital power-related data and time information. The time-based power-related data may include one or more of the following: (i) usage time information, (ii) load profile information, (iii) event log information, and (iv) demand information.

[0054] Usage time information may include a calendar set by the utility operator that defines the daily schedule, and energy and demand values ​​are structured for each set time period of the day, so that different charges or penalties are imposed for usage depending on the time.

[0055] Load profile information may include a set of configured metrics accumulated over a set interval length. At the end of the interval, the resulting value for each metric is stored in memory. Memory is allocated to store a series of these interval values. The data is then periodically retrieved and used to verify the consistency of total billing readings (by summing the interval values ​​for the same time period), to present trends in a given metric over time for internal use within the utility, or to provide information to end customers.

[0056] Power consumption measurement endpoints (e.g., electric meters) may be capable of recognizing a variety of events. These events may relate to electrical services (e.g., power loss and recovery, momentary voltage drops, momentary voltage rises, current overloads, etc.), measurement / communication infrastructure (e.g., time set on the meter, time when the meter configuration was changed), and / or internal meter diagnostic information (e.g., detected memory errors). Any of these types of events can be configured to be logged when they occur. Event log information typically records what type of event occurred, the date / time of the event, and optionally, some additional parameters that better describe the case (e.g., which phase of a three-phase meter experienced a momentary voltage drop).

[0057] Demand information may include one or more energy quantities (active, inactive, and / or apparent) accumulated over a set interval length. At the end of the interval length, the accumulated energy is divided by the interval length to obtain the average power over that interval, which is called the demand. This demand value can then be compared to a list of maximum demand values ​​for that metric held by the meter. If this new value is one of the new maximum values, it can be added to the list along with the date / time of this interval.

[0058] The functionality of the measurement application 306 described herein may be implemented in code (software), which is stored in the memory of a power consumption measurement endpoint having one or more storage media and is configured to run on a processor having one or more processing units. The processor may be, for example, a microprocessor or a microcontroller. Alternatively, some or all of the functionality of the measurement application 306 may be implemented in dedicated hardware circuitry (e.g., configurable hardware circuitry such as ASICs, simple circuits, gates, logic, and / or FPGAs).

[0059] As shown in Figures 3 and 4, the measurement application 306 is coupled to the serial port 310, thereby enabling communication of parameters and data between the measurement application 306 and the serial port 310. The measurement application 306 is coupled to the input device 312, thereby enabling the measurement application 306 to receive inputs (e.g., button presses). The measurement application 306 is coupled to the display device 314, thereby allowing visual data (e.g., display values) to be output to the display device 314.

[0060] It will be understood that the measurement application 306 requires accurate time information in order to accurately generate the time-based power-related data mentioned above.

[0061] Figure 3 shows a schematic block diagram of a power consumption measurement endpoint 106 according to several embodiments of the present disclosure. In particular, Figure 3 shows how a local clock 204 and a clock compensation module 206 may be implemented on a measurement unit 304. That is, the local clock 204 and the clock compensation module 206 may be components of the measurement unit 304. In these embodiments, processors 202, 222 may also implement the functions of the measurement application 306. Alternatively, in addition to processors 202, 222, a separate processor may be provided to perform the functions of the measurement application 306. In the embodiment of Figure 3, the communication unit 302 is configured to receive a reference clock time update output by the reference clock 108 and to supply the reference clock time update to the clock compensation module 206 on the measurement unit 304. The local clock 204 on the measurement unit 304 is configured to transmit a compensated time update to the measurement application 306 (based on at least one clock configuration message received from the clock compensation module 206).

[0062] Figure 4 shows a schematic block diagram of a power consumption measurement endpoint 106 according to another embodiment of the present disclosure. In particular, Figure 4 shows how a local clock 204 and a clock compensation module 206 may be implemented on a communication unit 302. That is, the local clock 204 and the clock compensation module 206 may be components of the communication unit 302. In these embodiments, the communication unit 302 is configured to receive a reference clock time update output by a reference clock 108, and the local clock 204 on the communication unit 302 is configured to transmit a compensated time update to a measurement application 306 (based on at least one clock configuration message received from the clock compensation module 206).

[0063] Figure 5 is a flowchart showing a method 500 that can be performed by the clock compensation module 206.

[0064] In step S502, the clock compensation module 206 initializes an integer value such that i = 1.

[0065] In step S504, the clock compensation module 206 receives the reference clock time update Clock_Ref i output by the reference clock 108. The clock compensation module 206 associates the reference clock time update received in step S504 with the current value of the integer value i maintained by the clock compensation module 206 in the memory of the power consumption measurement endpoint. It will be understood that the first reference clock time update received by the clock compensation module 206 is denoted as Clock_Ref1, and the subsequent received reference clock time updates are Clock_Ref2, Clock_Ref3, etc.

[0066] In step S506, when the clock compensation module 206 receives the reference clock time update Clock_Ref i in step S504, it records the time Clock_Local i of the local clock 204. 。 As described above, the clock compensation module 206 is configured to receive local clock time updates from the local clock 204.

[0067] In step S508, the clock compensation module 206 calculates the error Error i between the reference clock time update Clock_Ref i received in step S504 and the time of the local clock 204 recorded in step S506 (for example, in seconds). Specifically, the error can be calculated as Error i = Clock_Local i - Clock_Ref i and can be calculated as such.

[0068] In step S510, the clock compensation module 206 uses the error Errori and time for local clock 204 Clock_Local i This is stored in the memory of the power consumption measurement endpoint.

[0069] In step S512, the clock compensation module 206 determines whether a reference clock time update has been previously received (i.e., whether i ≥ 2). If the clock compensation module 206 determines that a reference clock time update has not been previously received (i.e., i = 1), the clock compensation module 206 increments the integer value i in step S514, and method 500 loops back to step S504, where a second reference clock time update Clock_Ref2 is received.

[0070] If the clock compensation module 206 determines that a reference clock time update has been previously received (i.e., i ≥ 2), the method 500 proceeds to step S516, where the clock compensation module 206 determines or modifies an approximation function of the error progression over time.

[0071] Once two reference clock time updates are received and two points are stored (each point is an error), i and time for local clock 204 Clock_Local i Using these points (corresponding to ), a linear equation can be formed to approximate the error at any given point in the future, for example, using linear approximation or curve fitting techniques. In particular, when i=2 in step S512, the clock compensation module 206 determines the approximation function.

[0072] When three or more reference clock time updates are received and three or more points are stored (each point is an error), i and time for local clock 204 Clock_Local i(corresponding to), for example, a higher-order equation can be created for the error using linear approximation or curve fitting techniques. That is, if i≧3 in step S512, the clock compensation module 206 modifies the previously established approximation function. With each new (e.g., periodic) update from the reference clock 108, the equation used can be recalculated using either the newly updated data points or the stored data point history.

[0073] Figure 6 shows the error at any given future point in time. i The waveform of an exemplary linear equation approximating the error is shown. The exemplary linear equation is calculated by the clock compensation module 206 based on (i) Error1 when the reference clock time update Clock_Ref1 is received at the time of Clock_Local1, (ii) Error2 when the reference clock time update Clock_Ref2 is received at the time of Clock_Local2, and (iii) calculation of the duration between Clock_Local1 and Clock_Local2. In this example, both Error1 and Error2 are positive, and Error i Error is increasing. i It will be understood that the value of can be negative in some scenarios.

[0074] Figure 7 is a flowchart showing the local clock update process 700 that can be performed by the clock compensation module 206.

[0075] In step S702, the clock compensation module 206 obtains the time (Clock_Local) of the local clock 204. As described above, the clock compensation module 206 is configured to receive local clock time updates from the local clock 204.

[0076] In step S704, the clock compensation module 206 determines the error between the local clock 204 and the reference clock 108 using the local clock time (Clock_Local) and a previously established approximation function. Figure 8 graphically shows how the data point 802 corresponding to the error in the local clock 204 time (Clock_Local) can be obtained using Clock_Local and the previously determined approximation function (a linear equation in this example).

[0077] In step S706, the clock compensation module 206 uses (i) the time of the local clock, Clock_Local, and (ii) the error between the local clock and the reference clock to compensate for the time (t comp ) is calculated. In particular, the compensated time is t comp =Clock_Local-Error It can be calculated as follows. In particular, the compensated time at any given point in time can be calculated by taking the local time and subtracting the approximate error calculation at that point in time using the most recently generated equation to approximate the error.

[0078] In step S706, the clock compensation module 206 sends at least one clock configuration message to the local clock 204 based on the compensated time in order to configure the local clock 204.

[0079] The clock compensation module 206 may send only a single clock configuration message to the local clock 204. The single clock configuration message is a compensated time t compThis may include: Alternatively, a single clock configuration message may include an instruction to the local clock 204 to accelerate or decelerate by a time value (e.g., in seconds) corresponding to the Error in order to correct for errors. The local clock 204 can be used to provide a precise timestamp associated with anomalies observed in the voltage or current waveform being measured. In these implementations, these events may be sent to a headend system (e.g., server 104) that collects such events for a number of devices. It is desirable that the timestamps of these events be as accurate as possible in order to correlate whether events sent by two temporally close devices correspond to the same event. In these implementations, it is preferable that the clock compensation module 206 immediately adjusts the local clock 204 to the most approximate time (by sending a single clock configuration message) so that the local clock 204 is tightly synchronized with the reference clock 108. In other embodiments, a single clock configuration message may include a rate at which the local clock 204 should adjust the time maintained by the local clock 204. For example, the rate can be in units of seconds / second, seconds / hour, or milliseconds / hour, so that the local clock 206 adjusts the amount in the numerator for each interval of the denominator measured by the local clock 204. The clock compensation module 206 can send multiple clock configuration messages to the local clock 204. The local clock 204 may also be used to measure a set interval length for integrating the measured values, and then the local clock 204 calculates values ​​associated with this integrated data and records them along with a timestamp at the end of the interval (for example, for demand and load profiles). A minute-based upper limit is used by the local clock 204 to terminate these intervals. If a change in time occurs within an interval, the duration of the interval may be longer or shorter than it actually is. If the change is sufficiently large, the interval value should be discarded or marked as short or long.In these implementations, it is preferable to extend the adjustments over several time intervals so that each interval is close enough to the correct duration without the need to discard or flag data. Therefore, the clock compensation module 206 can send multiple clock configuration messages to the local clock 204, each of which contains an instruction to the local clock 204 to accelerate or decelerate by a time value, and the sum of the time values ​​of each of the multiple clock configuration messages is equal to the error between the local clock 204 and the reference clock 108.

[0080] The clock compensation module 206 can operate according to both of these methods (i.e., by sending one or more clock configuration messages to the local clock 204) and can select the appropriate operating method depending on the specific measurement function being performed by the power consumption measurement endpoint 106.

[0081] At least one clock configuration message configures the local clock 204 to correct for any error between the local clock 204 and the reference clock 108. That is, the local clock 204 outputs a compensated time update based on at least one clock configuration message. In this specification, the time update output by the local clock 204 based on at least one clock configuration message is referred to as a compensated time update (a time update output by the local clock 204 after clock correction has been applied).

[0082] The local clock update process 700 can be executed at any time (not synchronized with the reception of reference clock time updates output by the reference clock 108).

[0083] The local clock update process 700 may be performed periodically by the clock compensation module 206. The frequency at which the local clock update process 700 is performed may be determined by the magnitude of the drift between the local clock 204 and the reference clock 108, and the accuracy that can be achieved by approximating the error. For example, if the reference clock time update is transmitted once every hour, the compensation algorithm may perform adjustments every 5 minutes. For the first few days, the error observed during the reference clock update may still be close to that of the uncompensated time, but as the number of data points increases, the error estimation algorithm is expected to improve, and performance improvements are anticipated. Conversely, even if the reference clock update rate is reduced to once a day, the same error as initially observed with an hourly update can be achieved.

[0084] By applying adjustments based on the calculated error and periodically updating the local clock, the error between the reference clock 108 and the local clock 204 can be brought to zero. This minimizes the amount of clock drift at the power consumption measurement endpoint between reference clock updates and reduces the frequency of reference clock updates. This results in a favorable reduction in network traffic on the mesh network 102.

[0085] Additionally or alternatively, the local clock update process 700, performed by the clock compensation module 206, may be triggered by an event. For example, the local clock update process 700 may be triggered when the approximation error exceeds a threshold. Clock drift is typically affected by temperature, which means that updates tend to be more frequent during the day when temperatures are high and less frequent at night.

[0086] From the above, it will be understood that embodiments of the present disclosure enable the accuracy of the local clock of a power consumption measurement endpoint relative to a reference clock to be maintained over time. This reduces the number of devices in the mesh network 102 that require a reference clock 108, as it is possible to rely on other devices (having a reference clock 108) to maintain accurate time. Furthermore, this prevents the power consumption measurement endpoint from logging and reporting erroneous time-related power consumption data.

[0087] In general, any of the functions described herein can be implemented using software, firmware, hardware (e.g., fixed logic circuits), or a combination of these implementations. The terms “module,” “function,” “component,” and “application” as used herein generally refer to software, firmware, hardware, or a combination thereof. In the case of a software implementation, a module, function, or logic represents program code that performs a specified task when executed on a processor (e.g., one or more CPUs). The program code may be stored in one or more computer-readable memory devices. The features of the techniques described below are platform-independent, meaning that these techniques can be implemented on a variety of commercial computing platforms with different processors.

[0088] While this disclosure has been described in terms of the specific embodiments described above, it should be understood that these embodiments are illustrative only and the claims are not limited to those embodiments. Those skilled in the art will be able to construct, taking this disclosure into consideration, modifications and alternative forms that are likely to be included in the appended claims. Each feature disclosed or illustrated herein may be incorporated into any embodiment, either alone or in any appropriate combination with any other feature disclosed or illustrated herein.

Claims

1. Power consumption measurement endpoint, Local clock and Clock compensation module and The clock compensation module is equipped with, The power consumption measurement endpoint receives multiple reference clock time updates output by an external reference clock, Each of the aforementioned multiple reference clock time updates records the time of the local clock that was received, Using the aforementioned multiple reference clock time updates and the time of the local clock, an approximate function of the change in the error over time between the local clock and the reference clock is determined. It is configured to do the following: The clock compensation module is further configured to perform a local clock update process, and the clock compensation module, To obtain the time of the aforementioned local clock, The error between the local clock and the reference clock is determined using the time of the local clock and the approximation function. (i) using the time of the local clock, and (ii) using the error between the local clock and the reference clock, calculate the compensated time, Based on the compensated time, at least one clock configuration message is sent to the local clock. It is further configured to do the following: A power consumption measurement endpoint in which the local clock is configured to output a time update based on the at least one clock configuration message.

2. The power consumption measurement endpoint according to claim 1, wherein the at least one clock configuration message comprises only a single clock configuration message, and the single clock configuration message includes the compensated time.

3. The power consumption measurement endpoint according to claim 1, wherein the at least one clock configuration message comprises only a single clock configuration message, and the single clock configuration message comprises an instruction to the local clock to accelerate or decelerate by a time value corresponding to the error between the local clock and the reference clock.

4. The power consumption measurement endpoint according to claim 1, wherein the at least one clock configuration message comprises a plurality of clock configuration messages, the clock compensation module is configured to transmit the plurality of clock configuration messages sequentially, each of the plurality of clock configuration messages comprises an instruction to the local clock to accelerate or decelerate by a time value, and the sum of the time values ​​of each of the plurality of clock configuration messages is equal to the error between the local clock and the reference clock.

5. The power consumption measurement endpoint according to any one of claims 1 to 4, wherein the clock compensation module is configured to receive one or more further reference clock time updates output by the reference clock, and to adapt the approximation function using the multiple reference clock time updates and the one or more further reference clock time updates.

6. A communication unit configured to receive the aforementioned multiple reference clock time updates, Measurement unit and A power consumption measurement endpoint comprising a measurement unit comprising a measurement application configured to generate time-based power-related data by associating (i) power-related data associated with power consumed in a power distribution system with the time update, The power consumption measurement endpoint according to any one of claims 1 to 5, wherein the communication unit is further configured to communicate the time-based power-related data to one or more external devices.

7. The power consumption measurement endpoint according to claim 6, wherein the measurement unit comprises the local clock and the clock compensation module.

8. The power consumption measurement endpoint according to claim 6, wherein the communication unit comprises the local clock and the clock compensation module.

9. The aforementioned measurement unit An interface to the power distribution system, wherein the analog power-related data is associated with the power consumed in the power distribution system; An analog / digital conversion circuit that converts the aforementioned analog power-related data into digital power-related data, A processor configured to process the aforementioned digital power-related data to generate the aforementioned power-related data and to supply the aforementioned power-related data to the measurement application, A power consumption measurement endpoint according to any one of claims 6 to 8, comprising:

10. The power consumption measurement endpoint according to any one of claims 6 to 9, wherein the communication unit is configured to communicate the time-based power-related data to one or more external devices via a mesh-based communication network.

11. The power consumption measurement endpoint according to any one of claims 1 to 10, wherein the clock compensation module is configured to periodically receive the reference clock time update.

12. The power consumption measurement endpoint according to any one of claims 1 to 11, wherein the clock compensation module is configured to periodically perform the local clock update process.

13. A power consumption measurement endpoint according to any one of claims 1 to 12, at least one network device and A mesh-based communication network comprising, wherein one of the at least one network device includes the reference clock.

14. The mesh-based communication network according to claim 13, wherein the network device including the reference clock is a further power consumption measurement endpoint.

15. The mesh-based communication network according to claim 13, wherein the network device including the reference clock is a server.

16. A method for updating the local clock on a power consumption measurement endpoint, the method being performed by a clock compensation module on the power consumption measurement endpoint, The power consumption measurement endpoint receives multiple reference clock time updates output by an external reference clock, Each of the aforementioned multiple reference clock time updates records the time of the local clock that was received, Using the aforementioned multiple reference clock time updates and the time of the local clock, an approximate function of the change in error over time between the local clock and the reference clock is determined. This involves performing a local clock update process. To obtain the time of the aforementioned local clock, The error between the local clock and the reference clock is determined using the time of the local clock and the approximation function. (i) using the time of the local clock, and (ii) using the error between the local clock and the reference clock, calculate the compensated time, Based on the compensated time, at least one clock configuration message is sent to the local clock. This involves performing the local clock update process and Methods that include...

17. At least one non-temporary computer-readable storage medium, which, when executed by at least one processor, includes instructions causing the at least one processor to perform the method according to claim 16.

Images