Method and device for detecting backup battery, electronic equipment and readable storage medium

Abstract

The application provides a backup battery detection method and device, electronic equipment and a readable storage medium, wherein the method comprises: in the process of providing power to a smart meter by a main power supply based on commercial power, controlling a MOS switch to be closed, so as to control a sampling circuit to collect an open circuit voltage of the backup battery when the MOS switch is closed; the open circuit voltage is a potential difference between a positive electrode and a negative electrode of the backup battery; controlling the MOS switch to be turned on, so that the backup battery is discharged through a load resistor; controlling the sampling circuit to continuously sample an instantaneous voltage value between the load resistor for multiple times within a first preset time length when the MOS switch is turned on; the instantaneous voltage value is a load voltage of the backup battery at the sampling time; receiving the open circuit voltage and the instantaneous voltage value collected by the sampling circuit, and determining a health state of the backup battery according to the open circuit voltage and the instantaneous voltage value. Through the method, the health state of the backup battery is detected in advance when the commercial power is supplied.

Description

Technical Field

[0001] This application relates to the field of electricity meter technology, and in particular to a method, apparatus, electronic device, and readable storage medium for detecting a backup battery. Background Technology

[0002] Single-phase and three-phase smart meters are intelligent devices in the field of electricity metering. These meters typically include a backup battery. In the event of a mains power outage, this backup battery powers the meter for about three minutes, allowing it to upload power data. However, if the backup battery malfunctions (e.g., is damaged), it cannot supply power to the meter. Therefore, the health of the backup battery is crucial.

[0003] Currently, backup battery failure is only discovered after a mains power outage, which is too late. Therefore, there is a need in the existing technology for a method to diagnose battery damage online when mains power is available. Summary of the Invention

[0004] In view of this, the purpose of this application is to provide a method, apparatus, electronic device and readable storage medium for detecting the health status of a backup battery in advance when the mains power is on.

[0005] In a first aspect, embodiments of this application provide a method for detecting a backup battery, wherein the backup battery is an energy storage device in a smart energy meter, and the backup battery is used to provide temporary power to the smart energy meter when the main power supply of the smart energy meter is interrupted; the main power supply is used to provide power to the smart energy meter based on mains power; the smart energy meter further includes: a controller, a current-limiting resistor, a load resistor, a MOS switch, and a sampling circuit; the output terminal of the controller is connected to one end of the current-limiting resistor, and the input terminal is connected to the output terminal of the sampling circuit; the gate of the MOS switch is connected to the other end of the current-limiting resistor, the drain is connected to the positive terminal of the backup battery, and the source is connected to one end of the load resistor; the positive input terminal of the sampling circuit is connected to the end of the load resistor near the source; the negative input terminal of the sampling circuit, the negative terminal of the backup battery, and the other end of the load resistor are connected to a common ground; the method is applied to the controller, and the method includes:

[0006] During the process of the main power supply providing power to the smart energy meter based on the mains power, the MOS switch is controlled to be turned off, so that when the MOS switch is turned off, the sampling circuit is controlled to collect the open circuit voltage of the backup battery; the open circuit voltage is the potential difference between the positive and negative terminals of the backup battery;

[0007] The MOS switch is controlled to be turned on so that the backup battery discharges through the load resistor. During the first preset duration of the MOS switch being turned on, the sampling circuit is controlled to continuously sample the instantaneous voltage value across the load resistor multiple times. The instantaneous voltage value is the load voltage of the backup battery at the sampling time.

[0008] The system receives the open-circuit voltage and the instantaneous voltage value collected by the sampling circuit, and determines the health status of the backup battery based on the open-circuit voltage and the instantaneous voltage value.

[0009] In conjunction with the first aspect, this application provides a first possible implementation of the first aspect, wherein controlling the MOS switch to turn off, and controlling the sampling circuit to acquire the open-circuit voltage of the backup battery when the MOS switch is off, includes:

[0010] The output low level controls the MOS switch to turn off. When the MOS switch is off, the sampling circuit is controlled to collect the voltage between the source and the common ground, and this voltage is used as the open circuit voltage of the backup battery.

[0011] In conjunction with the first aspect, this application provides a second possible implementation of the first aspect, wherein the smart energy meter further includes a temperature sensor for collecting the ambient temperature of the backup battery; before controlling the MOS switch to turn on, the method further includes:

[0012] The ambient temperature collected by the temperature sensor is acquired, and the internal resistance alarm threshold and internal resistance fault threshold of the backup battery at the ambient temperature are dynamically determined based on the ambient temperature; wherein, the ambient temperature is negatively correlated with the internal resistance alarm threshold and the internal resistance fault threshold; the internal resistance fault threshold is greater than the internal resistance alarm threshold.

[0013] Determining the health status of the backup battery based on the open-circuit voltage and the instantaneous voltage value includes:

[0014] The multiple instantaneous voltage values ​​sampled continuously are filtered to eliminate random noise interference, resulting in filtered voltage values.

[0015] The load current is obtained by calculating the ratio between the filtered voltage value and the resistance value of the load resistor.

[0016] Calculate the difference between the open-circuit voltage and the filtered voltage value, and use the ratio of this difference to the load current as the internal resistance of the backup battery;

[0017] The health status of the backup battery is determined by comparing its internal resistance with the internal resistance alarm threshold and the internal resistance fault threshold.

[0018] In conjunction with the second possible implementation of the first aspect, this application provides a third possible implementation of the first aspect, wherein comparing the internal resistance of the backup battery with the internal resistance alarm threshold and the internal resistance fault threshold, and determining the health status of the backup battery based on the comparison result, includes:

[0019] If the internal resistance of the backup battery is greater than the internal resistance fault threshold, it indicates that the health status of the backup battery is a battery fault, and the fault status of the backup battery is reported to the main station system.

[0020] If the internal resistance of the backup battery is greater than the internal resistance alarm threshold and less than the internal resistance fault threshold, then the difference between the open circuit voltage and the filtered voltage value is calculated, and this difference is taken as the voltage drop amplitude of the backup battery.

[0021] When the voltage drop exceeds a preset drop threshold, it indicates that the backup battery is in a battery fault state, and the fault state of the backup battery is reported to the main station system.

[0022] When the voltage drop is less than or equal to the preset drop threshold, the open-circuit voltage is compared with the minimum effective voltage threshold of the backup battery. When the open-circuit voltage is less than the minimum effective voltage threshold, it indicates that the backup battery is in a state of capacity depletion, and the capacity depletion state of the backup battery is reported to the master station system. When the open-circuit voltage is greater than or equal to the minimum effective voltage threshold, it indicates that the backup battery is in a state of early aging, and the early aging state of the backup battery is reported to the master station system for battery early warning.

[0023] If the internal resistance of the backup battery is less than or equal to the internal resistance alarm threshold, then the backup battery is considered to be in a healthy state.

[0024] In conjunction with the second possible implementation of the first aspect, this application provides a fourth possible implementation of the first aspect, wherein, after calculating the difference between the open-circuit voltage and the filtered voltage value, and using the ratio of this difference to the load current as the internal resistance of the backup battery, the method further includes:

[0025] The internal resistance of the backup battery is stored each time it is detected, and the slope of the change of the internal resistance of the backup battery over time is analyzed based on the internal resistance of the backup battery each time it is detected; the slope is used to represent the growth trend of the internal resistance of the backup battery.

[0026] If the slope is greater than the preset slope, it indicates that the health status of the backup battery is in an accelerated degradation state, and the accelerated degradation state of the backup battery is reported to the main station system for battery warning.

[0027] In conjunction with the first aspect, this application provides a fifth possible implementation of the first aspect, wherein the main power supply includes a surge protection unit, an EMC filtering module, an AC-DC switching power supply module with an integrated isolation transformer, and a bus filter unit in the smart energy meter; the surge protection unit includes a varistor and a transient suppression diode; the EMC filtering module includes a common-mode inductor with two independent windings, an X capacitor, a first Y capacitor, and a second Y capacitor; and the bus filter unit in the smart energy meter includes an electrolytic capacitor and a multilayer ceramic capacitor.

[0028] The varistor is connected in parallel between the live and neutral wires of the mains power supply, and the transient suppression diode is connected in parallel after the varistor. The two independent windings of the common-mode inductor are connected in series with the live and neutral wires, respectively. The X capacitor is connected in parallel between the live and neutral wires, located at either the input or output terminal of the common-mode inductor. One end of the first Y capacitor is connected to the live wire at the input terminal of the common-mode inductor, and the other end is connected to the protective ground of the smart energy meter. One end of the second Y capacitor is connected to the neutral wire at the input terminal of the common-mode inductor, and the other end is connected to the protective ground of the smart energy meter. The output terminal of the common-mode inductor is connected to the input terminal of the AC-DC switching power supply module of the integrated isolation transformer. An electrolytic capacitor is connected in parallel to the output terminal of the AC-DC switching power supply module of the integrated isolation transformer, and the multilayer ceramic capacitor is connected in parallel after the electrolytic capacitor.

[0029] Wherein, the main power source supplies power to the smart energy meter based on mains power:

[0030] The surge protection unit is used to protect against surge interference superimposed on the mains power supply.

[0031] The EMC filtering module is used to filter out high-frequency interference in the mains power supply so as to input filtered high-voltage AC power to the AC-DC switching power supply module of the integrated isolation transformer; wherein, the high-frequency interference includes differential-mode interference and common-mode interference; the common-mode inductor is used to suppress common-mode interference, the X capacitor is used to suppress differential-mode interference, the first Y capacitor is used to discharge the common-mode interference on the live wire through protective ground, and the second Y capacitor is used to discharge the common-mode interference on the neutral wire through protective ground;

[0032] The AC-DC switching power supply module of the integrated isolation transformer is used to isolate and step down the high-voltage AC power output by the EMC filter module, and output low-voltage DC power.

[0033] The electrolytic capacitor is used to filter out low-frequency ripple in the low-voltage DC power, and the multilayer ceramic capacitor is used to filter out high-frequency ripple in the low-voltage DC power. The filtered low-voltage DC power is used as the final bus voltage of the smart energy meter, and the final bus voltage is used to provide power to the controller and the sampling circuit in the smart energy meter.

[0034] In conjunction with the first aspect, this application provides a sixth possible implementation of the first aspect, wherein controlling the MOS switch to turn off during the process of the main power source supplying power to the smart energy meter based on mains power includes:

[0035] During the process of the main power source supplying power to the smart energy meter based on mains power, the input voltage of the mains power is monitored in real time;

[0036] If the stability of the mains input voltage reaches a preset stability standard within a second preset time period, the battery detection mode is triggered, and the MOS switch is controlled to turn off.

[0037] Secondly, embodiments of this application also provide a backup battery detection device, wherein the backup battery is an energy storage device in a smart energy meter, and the backup battery is used to provide temporary power to the smart energy meter when the main power supply of the smart energy meter is interrupted; the main power supply is used to provide power to the smart energy meter based on mains power; the smart energy meter further includes: a controller, a current-limiting resistor, a load resistor, a MOS switch, and a sampling circuit; the output terminal of the controller is connected to one end of the current-limiting resistor, and the input terminal is connected to the output terminal of the sampling circuit; the gate of the MOS switch is connected to the other end of the current-limiting resistor, the drain is connected to the positive terminal of the backup battery, and the source is connected to one end of the load resistor; the positive input terminal of the sampling circuit is connected to the end of the load resistor near the source; the negative input terminal of the sampling circuit, the negative terminal of the backup battery, and the other end of the load resistor are connected to a common ground; the device is applied to the controller, and the device includes:

[0038] The first control module is used to control the MOS switch to turn off during the process of the main power supply providing power to the smart energy meter based on the mains power, so as to control the sampling circuit to collect the open circuit voltage of the backup battery when the MOS switch is off; the open circuit voltage is the potential difference between the positive and negative terminals of the backup battery.

[0039] The second control module is used to control the MOS switch to be turned on so that the backup battery can discharge through the load resistor. During the first preset duration of the MOS switch being turned on, the sampling circuit is controlled to continuously sample the instantaneous voltage value across the load resistor multiple times. The instantaneous voltage value is the load voltage of the backup battery at the sampling time.

[0040] The determination module is used to receive the open-circuit voltage and the instantaneous voltage value collected by the sampling circuit, and determine the health status of the backup battery based on the open-circuit voltage and the instantaneous voltage value.

[0041] Thirdly, embodiments of this application also provide an electronic device, including: a processor, a memory, and a bus, wherein the memory stores machine-readable instructions executable by the processor, and when the electronic device is running, the processor communicates with the memory via the bus, and when the machine-readable instructions are executed by the processor, the steps in any of the possible implementations of the first aspect described above are performed.

[0042] Fourthly, embodiments of this application also provide a computer-readable storage medium storing a computer program, which, when executed by a processor, performs the steps in any of the possible implementations of the first aspect described above.

[0043] This application provides a method, apparatus, electronic device, and readable storage medium for detecting a backup battery. The method involves creating an independent load circuit (also called a battery health detection circuit) powered solely by the backup battery. This load circuit consists of the backup battery, a MOS switch, and a load resistor. When using mains power, a sampling circuit periodically collects the open-circuit voltage of the backup battery and the load voltage (i.e., instantaneous voltage value) on the load circuit. Based on the collected open-circuit voltage and load voltage, the health status of the backup battery can be detected in advance. This helps avoid discovering backup battery failure only after a mains power outage.

[0044] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0045] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0046] Figure 1 This paper shows a schematic diagram of the internal circuit structure of a smart energy meter provided in an embodiment of this application;

[0047] Figure 2 A flowchart of a backup battery detection method provided in an embodiment of this application is shown;

[0048] Figure 3 This paper shows a schematic diagram of the internal circuit structure of a main power supply provided in an embodiment of this application;

[0049] Figure 4 A schematic diagram of the structure of a backup battery detection device provided in an embodiment of this application is shown;

[0050] Figure 5 A schematic diagram of the structure of an electronic device provided in an embodiment of this application is shown. Detailed Implementation

[0051] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0052] Currently, backup battery failures are often only discovered after a mains power outage, which is too late. Therefore, this application provides a backup battery detection method, apparatus, electronic device, and readable storage medium to detect the health status of the backup battery in advance when mains power is available. The following embodiments describe these embodiments.

[0053] To facilitate understanding of this embodiment, a method for detecting a backup battery disclosed in this application will first be described in detail. The backup battery is an energy storage device in a smart meter. The backup battery is used to provide temporary power to the smart meter when the main power supply is interrupted; the main power supply is used to provide power to the smart meter based on mains power; such as Figure 1 As shown, the smart energy meter also includes: a controller, a current-limiting resistor, a load resistor, a MOS switch, and a sampling circuit; the output terminal of the controller is connected to one end of the current-limiting resistor, and the input terminal is connected to the output terminal of the sampling circuit; the gate (G) of the MOS switch is connected to the other end of the current-limiting resistor, the drain (D) is connected to the positive terminal of the backup battery, and the source (S) is connected to one end of the load resistor; the positive input terminal of the sampling circuit is connected to the end of the load resistor closest to the source (S); the negative input terminal of the sampling circuit, the negative terminal of the backup battery, and the other end of the load resistor are connected to the common ground GND.

[0054] In this embodiment, the smart meter can be a single-phase smart meter or a three-phase smart meter. The backup battery is the energy storage device in the smart meter, typically a 3.6V lithium-ion battery.

[0055] Normally, smart meters are powered by mains electricity. However, when the mains power fails, the main power supply of the smart meter will be interrupted. At this time, a backup battery is needed as a temporary power source to provide temporary power to the smart meter so that it can upload power data.

[0056] like Figure 1 As shown, in this embodiment, an independent load circuit (also known as a battery health detection circuit) powered solely by the backup battery is created in the smart energy meter. Since the negative terminal of the backup battery and the negative terminal of the load resistor are connected to the same common ground GND, the load circuit is as follows: positive terminal of the backup battery, drain (D) of the MOS switch, source (S) of the MOS switch, positive terminal of the load resistor, negative terminal of the load resistor, and common ground GND.

[0057] In this embodiment, the MOS switch is specifically a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor). The load resistor value needs to be calculated to simulate a suitable discharge load. For example, a resistance value is chosen such that the discharge current is around 10mA (e.g., 36Ω), which is sufficient to generate a measurable voltage change without significantly depleting the backup battery. The current-limiting resistor mainly serves a protective function, preventing accidental short circuits. The controller (MCU) is the main controller of the energy meter. The sampling circuit is specifically a voltage sampling circuit, which can be a simple voltage divider circuit.

[0058] In this embodiment, the connection relationships between the components of the smart energy meter are as follows: Figure 1 As shown, the negative input terminal of the sampling circuit, the negative terminal of the backup battery, and the other end of the load resistor are connected to the same common ground GND. This can be understood as the negative input terminal of the sampling circuit, the negative terminal of the backup battery, and the other end of the load resistor being interconnected.

[0059] The backup battery detection method is applied to the controller and is part of the smart meter's self-test program. It can be executed periodically, for example, once every 24 hours.

[0060] like Figure 2 As shown, the testing method for the backup battery includes the following steps:

[0061] S101: During the process of the main power supply providing power to the smart energy meter based on the mains power, the MOS switch is controlled to turn off, so that when the MOS switch is turned off, the sampling circuit is controlled to collect the open circuit voltage of the backup battery; the open circuit voltage is the potential difference between the positive and negative terminals of the backup battery.

[0062] S102: Control the MOS switch to turn on so that the backup battery can discharge through the load resistor. Within the first preset duration of the MOS switch being turned on, control the sampling circuit to sample the instantaneous voltage value across the load resistor multiple times. The instantaneous voltage value is the load voltage of the backup battery at the sampling time.

[0063] S103: Receives the open-circuit voltage and instantaneous voltage values ​​collected by the sampling circuit, and determines the health status of the backup battery based on the open-circuit voltage and instantaneous voltage values.

[0064] In step S101, since the purpose of this embodiment is to detect the health status of the backup battery when the mains power supply is used to supply power to the smart energy meter, it is necessary to control the MOS switch during the process of the main power supply providing power to the smart energy meter based on the mains power to start detecting the health status of the backup battery.

[0065] In one possible implementation, when executing step S101 to control the MOS switch to turn off, and when the MOS switch is off, controlling the sampling circuit to collect the open-circuit voltage of the backup battery, the specific steps can be as follows:

[0066] The low-level output controls the MOS switch to turn off. When the MOS switch is off, the control sampling circuit collects the voltage between the source and the common ground, and uses this voltage as the open-circuit voltage of the backup battery.

[0067] In this embodiment, the controller outputs a low level (typically 0V), which completely shuts off the MOS switch, thus disconnecting the load circuit. At this time, the path from the positive terminal of the backup battery to the load resistor is cut off, no current flows through it, and the backup battery is in an unloaded state.

[0068] When the MOS switch is off, the resistance between the drain (D) and source (S) is extremely high (in the megaohm range), which is equivalent to an open circuit. Therefore, there is almost no current in the path from the positive terminal of the backup battery to the drain (D) of the MOS switch, and thus no voltage drop.

[0069] At this point, the drain (D) voltage is "mapped" to the positive terminal of the load resistor through the positive terminal of the backup battery, the drain (D) of the MOS switch, and the source (S). Therefore, the voltage between the source (S) and GND is approximately equal to the voltage between the drain (D) and GND, which is also approximately equal to the open-circuit voltage of the backup battery. In other words, the voltage measured at the source (S) of the MOS switch is equal to the voltage at the positive terminal of the backup battery. The common ground (GMD) is directly connected to the negative terminal of the backup battery. Therefore, the voltage between the source (S) and the common ground (GND) sampled by the sampling circuit is the potential difference between the positive and negative terminals of the backup battery, i.e., the open-circuit voltage.

[0070] In step S102, the controller outputs a high level to turn on the MOS switch, connect the load circuit, and allow the backup battery to start discharging through the load resistor.

[0071] The controller turns on the MOS switch and controls the sampling circuit to continuously sample the instantaneous voltage value across the load resistor at a high rate (e.g., once every 1 ms) for a short period of time (e.g., a first preset duration of 100 ms), thus controlling the sampling circuit to sample 100 times. The purpose of this is to capture the dynamic characteristics of the backup battery voltage during the instantaneous drop and stabilization process from no-load to load, rather than just a static value. The instantaneous voltage value is the load voltage of the backup battery at the sampling time, directly reflecting the output voltage that the backup battery can maintain when driving this known load resistor at the sampling time.

[0072] The sampling circuit acquires an analog signal used to represent instantaneous voltage values. The circuit transmits the analog signals acquired at each sampling moment to the controller. The ADC in the controller converts the analog signal into a digital signal and then performs subsequent processing on the digital signal used to represent the instantaneous voltage values.

[0073] In step S103, after receiving the open-circuit voltage and multiple consecutive instantaneous voltage values ​​collected by the sampling circuit, the controller outputs a low level, disconnects the load circuit, and stops the backup battery from discharging. Furthermore, the controller analyzes the received open-circuit voltage and instantaneous voltage values ​​to determine the health status of the backup battery.

[0074] In one possible implementation, considering that the lower the ambient temperature of the backup battery, the greater the internal resistance of a healthy backup battery will naturally be, a simple threshold method might be misjudged as a fault. Therefore, to address this issue, this embodiment uses temperature compensation to dynamically determine the internal resistance alarm threshold and the internal resistance fault threshold, thereby improving the accuracy of fault diagnosis.

[0075] Specifically, the smart energy meter also includes a temperature sensor, which is used to collect the ambient temperature of the backup battery; before executing step S102 to control the MOS switch to turn on, the following steps can also be performed:

[0076] The ambient temperature is acquired by a temperature sensor, and the internal resistance alarm threshold and internal resistance fault threshold of the backup battery at that ambient temperature are dynamically determined. The ambient temperature is negatively correlated with the internal resistance alarm threshold and the internal resistance fault threshold. The internal resistance fault threshold is greater than the internal resistance alarm threshold.

[0077] In this embodiment, the controller can pre-store a temperature-internal resistance threshold table, which records the internal resistance alarm threshold and internal resistance fault threshold of the backup battery at different ambient temperatures. For example, at an ambient temperature of -40°C, the internal resistance alarm threshold is 150Ω and the internal resistance fault threshold is 200Ω. At an ambient temperature of 0°C, the internal resistance alarm threshold is 100Ω and the internal resistance fault threshold is 130Ω. Generally, the lower the ambient temperature, the higher the internal resistance alarm threshold and internal resistance fault threshold.

[0078] After acquiring the ambient temperature from the temperature sensor, the controller determines the corresponding internal resistance alarm threshold and internal resistance fault threshold from the temperature-internal resistance threshold table based on the ambient temperature.

[0079] When performing step S103, the specific steps S1031-S1034 can be followed:

[0080] S1031: Filter multiple instantaneous voltage values ​​sampled continuously to eliminate random noise interference and obtain the filtered voltage value.

[0081] S1032: Calculate the ratio between the filtered voltage value and the load resistance value to obtain the load current.

[0082] S1033: Calculate the difference between the open-circuit voltage and the filtered voltage value, and use the ratio of this difference to the load current as the internal resistance of the backup battery.

[0083] S1034: Compare the internal resistance of the backup battery with the internal resistance alarm threshold and the internal resistance fault threshold, and determine the health status of the backup battery based on the comparison results.

[0084] In step S1031, when filtering multiple instantaneous voltage values ​​sampled continuously, specific methods such as averaging or median filtering can be used to eliminate random noise interference and obtain a stable and reliable filtered voltage value.

[0085] In step S1032, the load current I can be calculated using the following formula. load :

[0086]

[0087] Among them, V load R represents the filtered voltage value. load This indicates the resistance value of the load resistor.

[0088] In step S1033, the internal resistance R of the backup battery can be calculated using the following formula. Internal :

[0089]

[0090] Among them, V open This indicates the open-circuit voltage.

[0091] In one possible implementation, when performing step S1034, the specific steps S10341-S10344 can be performed as follows:

[0092] S10341: If the internal resistance of the backup battery is greater than the internal resistance fault threshold, it indicates that the health status of the backup battery is a battery fault, and the fault status of the backup battery is reported to the main station system.

[0093] S10342: If the internal resistance of the backup battery is greater than the internal resistance alarm threshold and less than the internal resistance fault threshold, calculate the difference between the open circuit voltage and the filtered voltage value, and use this difference as the voltage drop amplitude of the backup battery.

[0094] S10343: When the voltage drop exceeds the preset drop threshold, it indicates that the backup battery is in a battery fault state, and the fault state of the backup battery is reported to the main station system.

[0095] S10344: When the voltage drop is less than or equal to the preset drop threshold, compare the open circuit voltage with the minimum effective voltage threshold of the backup battery; when the open circuit voltage is less than the minimum effective voltage threshold, it indicates that the backup battery is in a state of capacity depletion, and the capacity depletion state of the backup battery is reported to the master station system; when the open circuit voltage is greater than or equal to the minimum effective voltage threshold, it indicates that the backup battery is in a state of early aging, and the early aging state of the backup battery is reported to the master station system for battery early warning.

[0096] S10345: If the internal resistance of the backup battery is less than or equal to the internal resistance alarm threshold, it indicates that the backup battery is in a healthy state.

[0097] In step S10341, if the internal resistance R of the backup battery Internal Internal resistance fault threshold R fault (T) indicates that the chemical substances inside the backup battery have severely aged or dried out, making it unable to deliver sufficient current. The health status of the backup battery can be directly identified as a battery fault, and the fault status of the backup battery can be immediately reported to the main station system to issue a battery fault alarm.

[0098] In step S10342, if the internal resistance R of the backup battery Internal Internal resistance alarm threshold R warn (T), and at the same time, the internal resistance R of the backup battery Internal Internal resistance fault threshold R fault(T) indicates that the internal resistance of the backup battery has significantly exceeded the healthy range. The backup battery may still be able to function with difficulty, but its lifespan is nearing its end. In this case, it is necessary to incorporate the voltage drop of the backup battery for auxiliary judgment to prevent misjudgment.

[0099] The voltage drop of the backup battery can be calculated using the following formula. :

[0100]

[0101] Among them, V open V represents the open-circuit voltage. load This represents the filtered voltage value.

[0102] In step S10343, if the internal resistance R of the backup battery Internal Internal resistance alarm threshold R warn (T), and at the same time, the internal resistance R of the backup battery Internal Internal resistance fault threshold R fault (T), and the voltage drop of the backup battery. When the preset drop threshold is reached, it indicates that the internal resistance of the backup battery is critical and the voltage drop is huge. At this time, the health status of the backup battery is determined to be a battery fault, and the fault status of the backup battery must be reported to the main station system immediately to issue a battery fault alarm.

[0103] In step S10345, if the internal resistance R of the backup battery Internal Internal resistance alarm threshold R warn (T), and at the same time, the internal resistance R of the backup battery Internal Internal resistance fault threshold R fault (T), and the voltage drop of the backup battery. When the voltage drop is less than or equal to the preset threshold value, continue to compare the open-circuit voltage V. open With the minimum effective voltage threshold V of the backup battery min The size between them.

[0104] In this embodiment, V min This indicates the minimum output voltage that the backup battery can maintain to ensure the smart meter can perform its critical functions (such as data upload and last communication) after a power outage. For example, for a 3.6V backup battery, V... min It can be set to 3.2V.

[0105] If the open circuit voltage V open Minimum effective voltage threshold V minThis indicates that the backup battery not only has excessively high internal resistance, but also cannot maintain even the most basic open-circuit voltage. This means the backup battery's capacity is severely depleted, and it is unusable even if the internal resistance has not reached the absolute fault value. In this case, the backup battery's health status is determined to be depleted, and this depletion status is immediately reported to the master station system.

[0106] If the open circuit voltage V open ≥Minimum effective voltage threshold V min If the internal resistance of the backup battery has indeed increased, but its current load-bearing capacity and capacity are still within an acceptable range, this is usually a sign of early aging of the backup battery. In this case, the health status of the backup battery is determined to be an early aging state, and the early aging state of the backup battery is immediately reported to the main station system for battery early warning.

[0107] In step S10345, if the internal resistance R of the backup battery Internal Internal resistance alarm threshold R warn (T) indicates that the backup battery's internal resistance is within the normal range and the backup battery is in good health. No operation or battery health status report is performed at this time.

[0108] In one possible implementation, after performing step S1033 to calculate the difference between the open-circuit voltage and the filtered voltage value, and using the ratio of this difference to the load current as the internal resistance of the backup battery, the following steps S1035-S1036 can also be performed:

[0109] S1035: Store the internal resistance of the backup battery each time it is detected, and analyze the slope of the internal resistance of the backup battery changing with time based on the internal resistance of the backup battery each time it is detected; the slope is used to represent the growth trend of the internal resistance of the backup battery.

[0110] S1036: If the slope is greater than the preset slope, it indicates that the health status of the backup battery is in an accelerated degradation state. The accelerated degradation state of the backup battery is reported to the main station system for battery warning.

[0111] In this embodiment, the slope of the internal resistance change over time is analyzed. Even if the current internal resistance does not exceed the internal resistance threshold (internal resistance alarm threshold, internal resistance fault threshold), if its growth trend is very fast, an early warning can be issued to indicate that the backup battery performance is deteriorating rapidly.

[0112] In one possible implementation, mains power cannot be directly supplied to the smart meter; based on this, such as Figure 3As shown, the main power supply includes a surge protection unit, an EMC filter module, an AC-DC switching power supply module with an integrated isolation transformer, and a bus filter unit in the smart energy meter; the surge protection unit includes a varistor and a transient suppression diode; the EMC filter module includes a common-mode inductor with two independent windings, an X capacitor, a first Y capacitor, and a second Y capacitor; the bus filter unit in the smart energy meter includes an electrolytic capacitor and a multilayer ceramic capacitor;

[0113] A varistor is connected in parallel between the live and neutral wires of the mains power supply, and a transient suppression diode is connected in parallel after the varistor. Two independent windings of the common-mode inductor are connected in series with the live and neutral wires, respectively. An X capacitor is connected in parallel between the live and neutral wires, located at either the input or output terminal of the common-mode inductor. One end of the first Y capacitor is connected to the live wire at the input terminal of the common-mode inductor, and the other end is connected to the protective ground (L-PE) of the smart energy meter. One end of the second Y capacitor is connected to the neutral wire at the input terminal of the common-mode inductor, and the other end is connected to the protective ground (N-PE) of the smart energy meter. The output terminal of the common-mode inductor is connected to the input terminal of the AC-DC switching power supply module with an integrated isolation transformer. An electrolytic capacitor is connected in parallel to the output terminal of the AC-DC switching power supply module with an integrated isolation transformer, and a multilayer ceramic capacitor is connected in parallel after the electrolytic capacitor.

[0114] Among them, when the main power source supplies power to the smart energy meter based on the mains power:

[0115] Surge protection units are used to protect against surge interference superimposed on the mains power supply;

[0116] The EMC filter module is used to filter out high-frequency interference in the mains power supply so that the filtered high-voltage AC power is input to the AC-DC switching power supply module with integrated isolation transformer. The high-frequency interference includes differential-mode interference and common-mode interference. The common-mode inductor is used to suppress common-mode interference, the X capacitor is used to suppress differential-mode interference, the first Y capacitor is used to discharge the common-mode interference on the live wire through the protective ground, and the second Y capacitor is used to discharge the common-mode interference on the neutral wire through the protective ground.

[0117] The AC-DC switching power supply module with integrated isolation transformer is used to isolate and step down the high-voltage AC power output from the EMC filter module, and output low-voltage DC power.

[0118] Electrolytic capacitors are used to filter out low-frequency ripple in low-voltage DC power, while multilayer ceramic capacitors are used to filter out high-frequency ripple in low-voltage DC power. The filtered low-voltage DC power is used as the final bus voltage of the smart energy meter, which then provides power to the controller and sampling circuit in the smart energy meter.

[0119] In this embodiment, the mains power usually refers to 220VAC high-voltage AC power. Mains power is subject to surges (lightning strikes, grid impacts) and electromagnetic interference (EMI), so pretreatment is required to avoid damaging subsequent circuits.

[0120] In this system, a varistor (MOV, with extremely high resistance, typically several MΩ) and a transient voltage suppressor diode (TVS diode) are connected in parallel between the live and neutral wires of the mains power supply. When the voltage suddenly rises (such as a kV surge caused by a lightning strike), the varistor quickly short-circuits and discharges current, while the TVS diode clamps the voltage, protecting the downstream circuit.

[0121] The EMC filter module uses a common-mode inductor, an X capacitor, a first Y capacitor, and a second Y capacitor to "filter interference and discharge noise," providing a clean input power supply (such as 220VAC high-voltage AC power) for the AC-DC switching power supply module with an integrated isolation transformer.

[0122] The AC-DC switching power supply module with integrated isolation transformer is based on purified mains power for isolation and voltage reduction, and outputs stable low-voltage DC power (such as 12V DC).

[0123] It is worth noting that the high voltage and low voltage mentioned in this embodiment can be distinguished according to the preset high voltage threshold range and low voltage threshold range, but this embodiment will not provide a specific explanation of this.

[0124] In this embodiment, considering that although the AC-DC switching power supply module with integrated isolation transformer has built-in preliminary filtering, high-frequency ripple may still exist at the output (interference from the switching frequency of the switching power supply, such as tens of kHz to several MHz), further smoothing is required through "secondary filtering" to ensure the stability of the bus voltage. Therefore, one or two electrolytic capacitors (specifically high-frequency, low-impedance electrolytic capacitors, such as 220μF / 25V) are connected in parallel at the output terminal (between the positive and negative terminals) of the AC-DC switching power supply module with integrated isolation transformer to filter out low-frequency ripple (such as below 1kHz) using their large capacitance characteristics. Multilayer ceramic capacitors (MLCCs) (such as 0.1μF / 25V) are connected in parallel next to the electrolytic capacitors to filter out high-frequency ripple (such as 100kHz to 10MHz) using their high-frequency, low-impedance characteristics. The filtered low-voltage DC (such as 12V DC) is then used as the final bus voltage of the smart energy meter, which provides power to the controller, sampling circuit, and other components in the smart energy meter.

[0125] In one possible implementation, when controlling the MOS switch to turn off during step S101, which involves the main power supply providing power to the smart energy meter based on mains power, the specific steps S1011-S1012 can be performed as follows:

[0126] S1011: During the process of the main power source supplying power to the smart energy meter based on the mains power, the input voltage of the mains power is monitored in real time.

[0127] S1012: If the stability of the mains input voltage reaches the preset stability standard within the second preset time period, the battery detection mode is triggered, and the MOS switch is turned off.

[0128] In this embodiment, by monitoring the input voltage of the mains power (220V±10%) in real time, when the input voltage of the mains power is stable (no power outage / fluctuation) for 5 consecutive seconds, the battery detection mode is triggered, and the MOS switch is turned off to perform battery detection, so as to avoid false detection when the mains power is unstable.

[0129] Based on the same technical concept, this application also provides a backup battery detection device. The backup battery is an energy storage device in a smart energy meter. The backup battery is used to provide temporary power to the smart energy meter when the main power supply of the smart energy meter is interrupted. The main power supply is used to provide power to the smart energy meter based on mains power. The smart energy meter further includes: a controller, a current-limiting resistor, a load resistor, a MOS switch, and a sampling circuit. The output terminal of the controller is connected to one end of the current-limiting resistor, and the input terminal is connected to the output terminal of the sampling circuit. The gate of the MOS switch is connected to the other end of the current-limiting resistor, the drain is connected to the positive terminal of the backup battery, and the source is connected to one end of the load resistor. The positive input terminal of the sampling circuit is connected to the end of the load resistor near the source. The negative input terminal of the sampling circuit, the negative terminal of the backup battery, and the other end of the load resistor are connected to a common ground. The device is applied to the controller, such as... Figure 4 As shown, the device includes:

[0130] The first control module 401 is used to control the MOS switch to turn off during the process of the main power supply providing power to the smart energy meter based on the mains power, so as to control the sampling circuit to collect the open circuit voltage of the backup battery when the MOS switch is off; the open circuit voltage is the potential difference between the positive and negative terminals of the backup battery.

[0131] The second control module 402 is used to control the MOS switch to be turned on so that the backup battery can discharge through the load resistor. During the first preset duration of the MOS switch being turned on, the sampling circuit is controlled to continuously sample the instantaneous voltage value across the load resistor multiple times. The instantaneous voltage value is the load voltage of the backup battery at the sampling time.

[0132] The determination module 403 is used to receive the open-circuit voltage and the instantaneous voltage value collected by the sampling circuit, and determine the health status of the backup battery based on the open-circuit voltage and the instantaneous voltage value.

[0133] Optionally, when the first control module 401 controls the MOS switch to turn off, so as to control the sampling circuit to collect the open-circuit voltage of the backup battery when the MOS switch is off, it is specifically used for:

[0134] The output low level controls the MOS switch to turn off. When the MOS switch is off, the sampling circuit is controlled to collect the voltage between the source and the common ground, and this voltage is used as the open circuit voltage of the backup battery.

[0135] Optionally, the smart energy meter further includes a temperature sensor for collecting the ambient temperature of the backup battery; the device further includes:

[0136] The acquisition module is used to acquire the ambient temperature collected by the temperature sensor before the second control module 402 controls the MOS switch to be turned on, and dynamically determine the internal resistance alarm threshold and internal resistance fault threshold of the backup battery at the ambient temperature; wherein, the ambient temperature is negatively correlated with the internal resistance alarm threshold and the internal resistance fault threshold; the internal resistance fault threshold is greater than the internal resistance alarm threshold.

[0137] When determining the health status of the backup battery based on the open-circuit voltage and the instantaneous voltage value, the determining module 403 is specifically used for:

[0138] The multiple instantaneous voltage values ​​sampled continuously are filtered to eliminate random noise interference, resulting in filtered voltage values.

[0139] The load current is obtained by calculating the ratio between the filtered voltage value and the resistance value of the load resistor.

[0140] Calculate the difference between the open-circuit voltage and the filtered voltage value, and use the ratio of this difference to the load current as the internal resistance of the backup battery;

[0141] The health status of the backup battery is determined by comparing its internal resistance with the internal resistance alarm threshold and the internal resistance fault threshold.

[0142] Optionally, when the determining module 403 compares the internal resistance of the backup battery with the internal resistance alarm threshold and the internal resistance fault threshold, and determines the health status of the backup battery based on the comparison result, it is specifically used for:

[0143] If the internal resistance of the backup battery is greater than the internal resistance fault threshold, it indicates that the health status of the backup battery is a battery fault, and the fault status of the backup battery is reported to the main station system.

[0144] If the internal resistance of the backup battery is greater than the internal resistance alarm threshold and less than the internal resistance fault threshold, then the difference between the open circuit voltage and the filtered voltage value is calculated, and this difference is taken as the voltage drop amplitude of the backup battery.

[0145] When the voltage drop exceeds a preset drop threshold, it indicates that the backup battery is in a battery fault state, and the fault state of the backup battery is reported to the main station system.

[0146] When the voltage drop is less than or equal to the preset drop threshold, the open-circuit voltage is compared with the minimum effective voltage threshold of the backup battery. When the open-circuit voltage is less than the minimum effective voltage threshold, it indicates that the backup battery is in a state of capacity depletion, and the capacity depletion state of the backup battery is reported to the master station system. When the open-circuit voltage is greater than or equal to the minimum effective voltage threshold, it indicates that the backup battery is in a state of early aging, and the early aging state of the backup battery is reported to the master station system for battery early warning.

[0147] If the internal resistance of the backup battery is less than or equal to the internal resistance alarm threshold, then the backup battery is considered to be in a healthy state.

[0148] Optionally, after calculating the difference between the open-circuit voltage and the filtered voltage value, and using the ratio of this difference to the load current as the internal resistance of the backup battery, the determining module 403 is further configured to:

[0149] The internal resistance of the backup battery is stored each time it is detected, and the slope of the change of the internal resistance of the backup battery over time is analyzed based on the internal resistance of the backup battery each time it is detected; the slope is used to represent the growth trend of the internal resistance of the backup battery.

[0150] If the slope is greater than the preset slope, it indicates that the health status of the backup battery is in an accelerated degradation state, and the accelerated degradation state of the backup battery is reported to the main station system for battery warning.

[0151] Optionally, the main power supply includes a surge protection unit, an EMC filtering module, an AC-DC switching power supply module with an integrated isolation transformer, and a bus filter unit in the smart energy meter; the surge protection unit includes a varistor and a transient suppression diode; the EMC filtering module includes a common-mode inductor with two independent windings, an X capacitor, a first Y capacitor, and a second Y capacitor; the bus filter unit in the smart energy meter includes an electrolytic capacitor and a multilayer ceramic capacitor;

[0152] The varistor is connected in parallel between the live and neutral wires of the mains power supply, and the transient suppression diode is connected in parallel after the varistor. The two independent windings of the common-mode inductor are connected in series with the live and neutral wires, respectively. The X capacitor is connected in parallel between the live and neutral wires, located at either the input or output terminal of the common-mode inductor. One end of the first Y capacitor is connected to the live wire at the input terminal of the common-mode inductor, and the other end is connected to the protective ground of the smart energy meter. One end of the second Y capacitor is connected to the neutral wire at the input terminal of the common-mode inductor, and the other end is connected to the protective ground of the smart energy meter. The output terminal of the common-mode inductor is connected to the input terminal of the AC-DC switching power supply module of the integrated isolation transformer. An electrolytic capacitor is connected in parallel to the output terminal of the AC-DC switching power supply module of the integrated isolation transformer, and the multilayer ceramic capacitor is connected in parallel after the electrolytic capacitor.

[0153] Wherein, the main power source supplies power to the smart energy meter based on mains power:

[0154] The surge protection unit is used to protect against surge interference superimposed on the mains power supply.

[0155] The EMC filtering module is used to filter out high-frequency interference in the mains power supply so as to input filtered high-voltage AC power to the AC-DC switching power supply module of the integrated isolation transformer; wherein, the high-frequency interference includes differential-mode interference and common-mode interference; the common-mode inductor is used to suppress common-mode interference, the X capacitor is used to suppress differential-mode interference, the first Y capacitor is used to discharge the common-mode interference on the live wire through protective ground, and the second Y capacitor is used to discharge the common-mode interference on the neutral wire through protective ground;

[0156] The AC-DC switching power supply module of the integrated isolation transformer is used to isolate and step down the high-voltage AC power output by the EMC filter module, and output low-voltage DC power.

[0157] The electrolytic capacitor is used to filter out low-frequency ripple in the low-voltage DC power, and the multilayer ceramic capacitor is used to filter out high-frequency ripple in the low-voltage DC power. The filtered low-voltage DC power is used as the final bus voltage of the smart energy meter, and the final bus voltage is used to provide power to the controller and the sampling circuit in the smart energy meter.

[0158] Optionally, when the first control module 401 controls the MOS switch to turn off during the process of the main power source supplying power to the smart energy meter based on mains power, it is specifically used for:

[0159] During the process of the main power source supplying power to the smart energy meter based on mains power, the input voltage of the mains power is monitored in real time;

[0160] If the stability of the mains input voltage reaches a preset stability standard within a second preset time period, the battery detection mode is triggered, and the MOS switch is controlled to turn off.

[0161] Figure 5 A schematic diagram of an electronic device provided in this application embodiment includes: a processor 501, a memory 502, and a bus 503. The memory 502 stores machine-readable instructions executable by the processor 501. When the electronic device runs the above-described information processing method, the processor 501 and the memory 502 communicate through the bus 503. The processor 501 executes the machine-readable instructions to perform the steps of the method described in Embodiment 1.

[0162] This application also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, performs the steps described in Embodiment 1.

[0163] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the devices, electronic devices, and computer-readable storage media described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0164] In the several embodiments provided in this application, it should be understood that the disclosed methods, apparatuses, electronic devices, and computer-readable storage media can be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the division of modules is only a logical functional division, and in actual implementation, there may be other division methods. Furthermore, multiple modules or components may be combined or integrated into another system, or some features may be ignored or not executed. Additionally, the displayed or discussed mutual couplings, direct couplings, or communication connections may be through some communication interfaces; indirect couplings or communication connections between devices or modules may be electrical, mechanical, or other forms.

[0165] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0166] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0167] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a processor-executable, non-volatile, computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0168] Finally, it should be noted that the above-described embodiments are merely specific implementations of this application, used to illustrate the technical solutions of this application, and not to limit them. The scope of protection of this application is not limited thereto. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features, within the scope of the technology disclosed in this application. Such modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of protection of the claims.

Claims

1. A method for testing a backup battery, characterized in that, The backup battery is an energy storage device in the smart energy meter, used to provide temporary power to the smart energy meter when the main power supply is interrupted; the main power supply is used to provide power to the smart energy meter based on mains power; the smart energy meter also includes: a controller, a current-limiting resistor, a load resistor, a MOS switch, a sampling circuit, and a temperature sensor; the output terminal of the controller is connected to one end of the current-limiting resistor, and the input terminal is connected to the output terminal of the sampling circuit; the gate of the MOS switch is connected to the other end of the current-limiting resistor, the drain is connected to the positive terminal of the backup battery, and the source is connected to one end of the load resistor; the positive input terminal of the sampling circuit is connected to the end of the load resistor closest to the source; the negative input terminal of the sampling circuit, the negative terminal of the backup battery, and the other end of the load resistor are connected to a common ground; the temperature sensor is used to collect the ambient temperature of the backup battery; the method is applied to the controller, and the method includes: During the process of the main power supply providing power to the smart energy meter based on the mains power, the MOS switch is controlled to be turned off, so that when the MOS switch is turned off, the sampling circuit is controlled to collect the open circuit voltage of the backup battery; the open circuit voltage is the potential difference between the positive and negative terminals of the backup battery; The ambient temperature collected by the temperature sensor is obtained, and the internal resistance alarm threshold and internal resistance fault threshold of the backup battery at the ambient temperature are dynamically determined based on the ambient temperature. The MOS switch is controlled to be turned on so that the backup battery discharges through the load resistor. During the first preset duration of the MOS switch being turned on, the sampling circuit is controlled to continuously sample the instantaneous voltage value across the load resistor multiple times. The instantaneous voltage value is the load voltage of the backup battery at the sampling time. The open-circuit voltage and instantaneous voltage value collected by the sampling circuit are received, and multiple consecutively sampled instantaneous voltage values ​​are filtered to eliminate random noise interference, thereby obtaining the filtered voltage value. The load current is obtained by calculating the ratio between the filtered voltage value and the resistance value of the load resistor. Calculate the difference between the open-circuit voltage and the filtered voltage value, and use the ratio of this difference to the load current as the internal resistance of the backup battery; If the internal resistance of the backup battery is greater than the internal resistance fault threshold, it indicates that the health status of the backup battery is a battery fault, and the fault status of the backup battery is reported to the main station system. If the internal resistance of the backup battery is greater than the internal resistance alarm threshold and less than the internal resistance fault threshold, then the difference between the open circuit voltage and the filtered voltage value is calculated, and this difference is taken as the voltage drop amplitude of the backup battery. When the voltage drop exceeds a preset drop threshold, it indicates that the backup battery is in a battery fault state, and the fault state of the backup battery is reported to the main station system. When the voltage drop is less than or equal to the preset drop threshold, the open-circuit voltage is compared with the minimum effective voltage threshold of the backup battery. When the open-circuit voltage is less than the minimum effective voltage threshold, it indicates that the backup battery is in a state of capacity depletion, and the capacity depletion state of the backup battery is reported to the master station system. When the open-circuit voltage is greater than or equal to the minimum effective voltage threshold, it indicates that the backup battery is in a state of early aging, and the early aging state of the backup battery is reported to the master station system for battery early warning. If the internal resistance of the backup battery is less than or equal to the internal resistance alarm threshold, then the backup battery is in a healthy state. The internal resistance of the backup battery is stored each time it is detected, and the slope of the change of the internal resistance of the backup battery over time is analyzed based on the internal resistance of the backup battery each time it is detected; the slope is used to represent the growth trend of the internal resistance of the backup battery. If the slope is greater than the preset slope, it indicates that the health status of the backup battery is in an accelerated degradation state, and the accelerated degradation state of the backup battery is reported to the main station system for battery warning.

2. The method according to claim 1, characterized in that, The control of the MOS switch to turn off, and the control of the sampling circuit to acquire the open-circuit voltage of the backup battery when the MOS switch is off, includes: The output low level controls the MOS switch to turn off. When the MOS switch is off, the sampling circuit is controlled to collect the voltage between the source and the common ground, and this voltage is used as the open circuit voltage of the backup battery.

3. The method according to claim 1, characterized in that, The ambient temperature is negatively correlated with the internal resistance alarm threshold and the internal resistance fault threshold; the internal resistance fault threshold is greater than the internal resistance alarm threshold.

4. The method according to claim 1, characterized in that, The main power supply includes a surge protection unit, an EMC filter module, an AC-DC switching power supply module with an integrated isolation transformer, and a bus filter unit in the smart energy meter; the surge protection unit includes a varistor and a transient suppression diode; The EMC filtering module includes: a common-mode inductor with two independent windings, an X capacitor, a first Y capacitor, and a second Y capacitor; the bus filtering unit in the smart energy meter includes an electrolytic capacitor and a multilayer ceramic capacitor. The varistor is connected in parallel between the live and neutral wires of the mains power supply, and the transient suppression diode is connected in parallel after the varistor. The two independent windings of the common-mode inductor are connected in series with the live and neutral wires, respectively. The X capacitor is connected in parallel between the live and neutral wires, located at either the input or output terminal of the common-mode inductor. One end of the first Y capacitor is connected to the live wire at the input terminal of the common-mode inductor, and the other end is connected to the protective ground of the smart energy meter. One end of the second Y capacitor is connected to the neutral wire at the input terminal of the common-mode inductor, and the other end is connected to the protective ground of the smart energy meter. The output terminal of the common-mode inductor is connected to the input terminal of the AC-DC switching power supply module of the integrated isolation transformer. An electrolytic capacitor is connected in parallel to the output terminal of the AC-DC switching power supply module of the integrated isolation transformer, and the multilayer ceramic capacitor is connected in parallel after the electrolytic capacitor. Wherein, the main power source supplies power to the smart energy meter based on mains power: The surge protection unit is used to protect against surge interference superimposed on the mains power supply. The EMC filtering module is used to filter out high-frequency interference in the mains power supply so as to input filtered high-voltage AC power to the AC-DC switching power supply module of the integrated isolation transformer; wherein, the high-frequency interference includes differential-mode interference and common-mode interference; the common-mode inductor is used to suppress common-mode interference, the X capacitor is used to suppress differential-mode interference, the first Y capacitor is used to discharge the common-mode interference on the live wire through protective ground, and the second Y capacitor is used to discharge the common-mode interference on the neutral wire through protective ground; The AC-DC switching power supply module of the integrated isolation transformer is used to isolate and step down the high-voltage AC power output by the EMC filter module, and output low-voltage DC power. The electrolytic capacitor is used to filter out low-frequency ripple in the low-voltage DC power, and the multilayer ceramic capacitor is used to filter out high-frequency ripple in the low-voltage DC power. The filtered low-voltage DC power is used as the final bus voltage of the smart energy meter, and the final bus voltage is used to provide power to the controller and the sampling circuit in the smart energy meter.

5. The method according to claim 1, characterized in that, During the process of the main power source supplying power to the smart energy meter based on mains power, controlling the MOS switch to turn off includes: During the process of the main power source supplying power to the smart energy meter based on mains power, the input voltage of the mains power is monitored in real time; If the stability of the mains input voltage reaches a preset stability standard within a second preset time period, the battery detection mode is triggered, and the MOS switch is controlled to turn off.

6. A backup battery detection device, characterized in that, The backup battery is an energy storage device in the smart energy meter, used to provide temporary power to the smart energy meter when the main power supply is interrupted; the main power supply is used to provide power to the smart energy meter based on mains power; the smart energy meter also includes: a controller, a current-limiting resistor, a load resistor, a MOS switch, a sampling circuit, and a temperature sensor; the output terminal of the controller is connected to one end of the current-limiting resistor, and the input terminal is connected to the output terminal of the sampling circuit; the gate of the MOS switch is connected to the other end of the current-limiting resistor, the drain is connected to the positive terminal of the backup battery, and the source is connected to one end of the load resistor; the positive input terminal of the sampling circuit is connected to the end of the load resistor closest to the source; the negative input terminal of the sampling circuit, the negative terminal of the backup battery, and the other end of the load resistor are connected to a common ground; the temperature sensor is used to collect the ambient temperature of the backup battery; the device is applied to the controller, and the device includes: The first control module is used to control the MOS switch to turn off during the process of the main power supply providing power to the smart energy meter based on the mains power, so as to control the sampling circuit to collect the open circuit voltage of the backup battery when the MOS switch is off; the open circuit voltage is the potential difference between the positive and negative terminals of the backup battery. The acquisition module is used to acquire the ambient temperature collected by the temperature sensor, and dynamically determine the internal resistance alarm threshold and internal resistance fault threshold of the backup battery at the ambient temperature based on the ambient temperature. The second control module is used to control the MOS switch to be turned on so that the backup battery can discharge through the load resistor. During the first preset duration of the MOS switch being turned on, the sampling circuit is controlled to continuously sample the instantaneous voltage value across the load resistor multiple times. The instantaneous voltage value is the load voltage of the backup battery at the sampling time. The determination module is used for: The open-circuit voltage and instantaneous voltage value collected by the sampling circuit are received, and multiple consecutively sampled instantaneous voltage values ​​are filtered to eliminate random noise interference, thereby obtaining the filtered voltage value. The load current is obtained by calculating the ratio between the filtered voltage value and the resistance value of the load resistor. Calculate the difference between the open-circuit voltage and the filtered voltage value, and use the ratio of this difference to the load current as the internal resistance of the backup battery; If the internal resistance of the backup battery is greater than the internal resistance fault threshold, it indicates that the health status of the backup battery is a battery fault, and the fault status of the backup battery is reported to the main station system. If the internal resistance of the backup battery is greater than the internal resistance alarm threshold and less than the internal resistance fault threshold, then the difference between the open circuit voltage and the filtered voltage value is calculated, and this difference is taken as the voltage drop amplitude of the backup battery. When the voltage drop exceeds a preset drop threshold, it indicates that the backup battery is in a battery fault state, and the fault state of the backup battery is reported to the main station system. When the voltage drop is less than or equal to the preset drop threshold, the open-circuit voltage is compared with the minimum effective voltage threshold of the backup battery. When the open-circuit voltage is less than the minimum effective voltage threshold, it indicates that the backup battery is in a state of capacity depletion, and the capacity depletion state of the backup battery is reported to the master station system. When the open-circuit voltage is greater than or equal to the minimum effective voltage threshold, it indicates that the backup battery is in a state of early aging, and the early aging state of the backup battery is reported to the master station system for battery early warning. If the internal resistance of the backup battery is less than or equal to the internal resistance alarm threshold, then the backup battery is in a healthy state. The internal resistance of the backup battery is stored each time it is detected, and the slope of the change of the internal resistance of the backup battery over time is analyzed based on the internal resistance of the backup battery each time it is detected; the slope is used to represent the growth trend of the internal resistance of the backup battery. If the slope is greater than the preset slope, it indicates that the health status of the backup battery is in an accelerated degradation state, and the accelerated degradation state of the backup battery is reported to the main station system for battery warning.

7. An electronic device, characterized in that, include: The device includes a processor, a memory, and a bus, wherein the memory stores machine-readable instructions executable by the processor, and when the electronic device is in operation, the processor communicates with the memory via the bus, and the machine-readable instructions, when executed by the processor, perform the steps of the method as described in any one of claims 1 to 5.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, performs the steps of the method as described in any one of claims 1 to 5.

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