System and method for detecting battery state of uninterruptible power supply

Abstract

The invention discloses a system and a method for detecting the battery state of an uninterruptible power supply. The detection method comprises the steps of obtaining a current sampling signal detected by the current sampling module; acquiring a voltage sampling signal detected by a voltage sampling module; and judging a battery missing state according to the current sampling signal and the voltage sampling signal. According to the invention, the charging circuit does not need to be started or stopped, the system interference and stability problems caused by the detection process are avoided, the difference between the normal saturation of the battery and the lack of the battery can be effectively distinguished, the misjudgment risk generated at the last stage of battery charging is avoided, and the accuracy of the judgment result is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power supply, in particular to a detection system and method for battery state of uninterruptible power supply. BACKGROUND

[0002] As a key power guarantee device, uninterruptible power supply (UPS) has been widely used in important fields such as communication, power, mining and emergency management. Its core function is to provide stable and uninterrupted power for various power electronic devices, greatly improving the operation reliability of load-bearing devices in industrial systems. A typical modern UPS power supply system mainly consists of a switching power supply, a backup battery and a battery charge and discharge management circuit. When the power grid is normal, the UPS power supply system converts AC power into DC power, which is used to power the load and charge the backup battery. When the AC power is interrupted, the system can seamlessly switch to battery power mode to ensure continuous operation of the load. In this system, the online state of the battery is a key indicator for evaluating whether the UPS power supply system can perform its backup function when the power is cut off.

[0003] Currently, some solutions detect the battery state by detecting the output voltage of the charger. However, many chargers will periodically perform a pre-charge program when there is no battery connected, resulting in a constant voltage at the output end, making the voltage threshold-based judgment method often ineffective. To solve this problem, existing technologies (such as patent CN111999662B) propose to identify the absence of a battery by monitoring the charging current: when the charging current is below a threshold, the charger is actively disconnected and the battery voltage is detected to determine whether it has dropped. This solution can detect the absence of a battery, but when the battery is almost full, the charging current will also naturally drop to a very low level, which will frequently trigger the detection mechanism. This will cause the system to repeatedly start and stop the charger at the end of the normal charging of the battery. This frequent operation not only interferes with the normal maintenance of the battery, but also impacts the charging circuit, reducing the long-term stability and reliability of the entire system.

[0004] Therefore, there is an urgent need for a solution that can accurately detect the absence of a battery while effectively avoiding unnecessary frequent operations on the charging circuit during normal battery charging. SUMMARY

[0005] The present application provides a detection system and method for battery state of uninterruptible power supply, which does not require any start-stop operation on the charging circuit, avoiding interference with the charging circuit and improving the stability of the system and the accuracy of the judgment result.

[0006] In a first aspect, the present application provides a method for detecting the state of a battery of an uninterruptible power supply, which is executed by a detection system for the state of a battery of an uninterruptible power supply, the detection system comprising an uninterruptible power supply module, a voltage sampling module and a current sampling module; the first end of the voltage sampling module is connected to the uninterruptible power supply module, and the first end of the current sampling module is connected to the uninterruptible power supply module.

[0007] The detection method comprises:

[0008] obtaining a current sampling signal detected by the current sampling module;

[0009] obtaining a voltage sampling signal detected by the voltage sampling module;

[0010] judging a battery missing state according to the current sampling signal and the voltage sampling signal.

[0011] Optionally, judging a battery missing state according to the current sampling signal and the voltage sampling signal comprises:

[0012] when the current sampling signal is less than or equal to a preset current threshold, finding a minimum value of the voltage sampling signal in a preset time interval as a period to obtain a sampling voltage minimum value;

[0013] when the sampling voltage minimum values found in a first preset number of times successively are all less than or equal to a preset voltage threshold, determining that the battery is missing.

[0014] Optionally, when the sampling voltage minimum values found in a first preset number of times successively are all less than or equal to a preset voltage threshold, determining that the battery is missing comprises:

[0015] when the sampling voltage minimum value is less than or equal to the preset voltage threshold, increasing a first cumulative number by one, when the sampling voltage minimum value is greater than the preset voltage threshold, resetting the first cumulative number to zero, and when the first cumulative number is equal to the first preset number, determining that the battery is missing.

[0016] Optionally, when the current sampling signal is less than or equal to a preset current threshold, finding a minimum value of the voltage sampling signal in a preset time interval as a period to obtain a sampling voltage minimum value, and simultaneously comprises:

[0017] when the current sampling signals collected in a second preset number of times successively are all greater than the preset current threshold, determining that the battery is not missing, and stopping obtaining the voltage sampling signal.

[0018] Optionally, when the current sampling signals collected in a continuous second preset number of times are all greater than the preset current threshold, it is determined that the battery is not missing, comprising:

[0019] When the current sampling signal is greater than the preset current threshold, the second cumulative number is increased by one, and when the current sampling signal is less than or equal to the preset current threshold, the second cumulative number is cleared, until the second cumulative number is equal to the second preset number, it is determined that the battery is not missing.

[0020] Optionally, according to the current sampling signal and the voltage sampling signal, the battery missing state is determined, comprising:

[0021] According to the current sampling signal and the voltage sampling signal, the instantaneous charging power is calculated;

[0022] The absolute value of the difference between the previous instantaneous charging power and the subsequent instantaneous charging power is calculated;

[0023] The sum of all the absolute values in the preset time interval is calculated to obtain the instantaneous power change value;

[0024] When the instantaneous power change values calculated in a continuous third preset number of times are all greater than or equal to a preset power change threshold, it is determined that the battery is missing.

[0025] Optionally, when the instantaneous power change values calculated in a continuous third preset number of times are all greater than or equal to a preset power change threshold, it is determined that the battery is missing, comprising:

[0026] When the instantaneous power change value is greater than or equal to the preset power change threshold, the third cumulative number is increased by one, and when the instantaneous power change value is less than the preset power change threshold, the third cumulative number is cleared, until the third cumulative number is equal to the third preset number, it is determined that the battery is missing.

[0027] Optionally, before obtaining the current sampling signal detected by the current sampling module, it further comprises:

[0028] The uninterruptible power supply module is actively controlled to be in a battery missing state;

[0029] Obtain the voltage sampling signal detected by the voltage sampling module;

[0030] According to the voltage sampling signal, the preset time interval is determined.

[0031] Optionally, before determining the battery missing state according to the current sampling signal and the voltage sampling signal, it further comprises:

[0032] analog-to-digital converting the current sampling signal and the voltage sampling signal;

[0033] filtering the current sampling signal and the voltage sampling signal.

[0034] In a second aspect, the present application further provides a detection system for battery state of an uninterruptible power supply, which is used to execute the detection method for battery state of an uninterruptible power supply as any one of the first aspect; the detection system comprises an uninterruptible power supply module, a voltage sampling module, a current sampling module and a processor;

[0035] The first end of the voltage sampling module is connected with the uninterruptible power supply module, which is used to detect the charging voltage of the uninterruptible power supply module and obtain a voltage sampling signal; the second end of the voltage sampling module is connected with the processor;

[0036] The first end of the current sampling module is connected with the uninterruptible power supply module, which is used to detect the charging current of the uninterruptible power supply module and obtain a current sampling signal; the second end of the current sampling module is connected with the processor;

[0037] The processor is used to determine the state of the uninterruptible power supply module according to the voltage sampling signal and the current sampling signal.

[0038] The detection system and method for battery state of an uninterruptible power supply provided by the present application can detect the charging voltage and charging current in the uninterruptible power supply module respectively by setting the voltage sampling module and the current sampling module between the uninterruptible power supply module and the processor, and obtain the voltage sampling signal and the current sampling signal; the processor can determine the missing state of the battery based on the difference between the voltage sampling signal and the current sampling signal in the battery missing and non-missing states, without any start-stop operation on the charging circuit, which avoids the system interference and stability problems caused by the detection process, and can effectively distinguish the difference between the normal saturation of the battery and the missing of the battery, avoiding the misjudgment risk at the end of the battery charging period, and improving the accuracy of the judgment result. BRIEF DESCRIPTION OF DRAWINGS

[0039] Figure 1 The structure schematic diagram of the detection system for battery state of an uninterruptible power supply provided by the embodiment of the present application;

[0040] Figure 2 The structure schematic diagram of another detection system for battery state of an uninterruptible power supply provided by the embodiment of the present application;

[0041] Figure 3 The waveform schematic diagram of the charging voltage and the charging current provided by the embodiment of the present application;

[0042] Figure 4A flowchart of a method for detecting the state of a battery of an uninterruptible power supply according to an embodiment of the present application is shown in FIG. 1.

[0043] Figure 5 A flowchart of a method for detecting the state of a battery of an uninterruptible power supply according to another embodiment of the present application is shown in FIG. 2.

[0044] Figure 6 A flowchart of a method for detecting the state of a battery of an uninterruptible power supply according to yet another embodiment of the present application is shown in FIG. 3.

[0045] Figure 7 A flowchart of a method for detecting the state of a battery of an uninterruptible power supply according to yet another embodiment of the present application is shown in FIG. 4.

[0046] Figure 8 A waveform diagram of a transient charging power according to an embodiment of the present application is shown in FIG. 5.

[0047] Figure 9 A flowchart of a method for detecting the state of a battery of an uninterruptible power supply according to yet another embodiment of the present application is shown in FIG. 6. DETAILED DESCRIPTION

[0048] The present application will be further described below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are intended to be merely illustrative of the present application and not in limitation thereof. It should also be noted that, for the purpose of description, only the parts related to the present application are shown in the drawings rather than all the parts.

[0049] The terms used in the embodiments of the present application are merely intended for the purpose of describing specific embodiments and are not intended to limit the present application. It should be noted that the terms "upper", "lower", "left", "right", and the like described in the embodiments of the present application are described in the angle shown in the drawings and should not be construed as limiting the embodiments of the present application. In addition, it should be understood in the context that when one element is mentioned to be formed "on" or "under" another element, it can be directly formed "on" or "under" another element or indirectly formed "on" or "under" another element through an intermediate element. The terms "first", "second", and the like are merely for the purpose of description and do not represent any order, quantity, or importance, but are merely used to distinguish different components. The specific meanings of the above terms in the present application can be understood by those skilled in the art according to the specific circumstances.

[0050] The term "comprising" and its variations used in the present application are open and inclusive, i.e., "including but not limited to". The term "based on" is "at least partially based on". The term "one embodiment" means "at least one embodiment".

[0051] It should be noted that the "first", "second" and the like mentioned in the present application are only used to distinguish the corresponding content, and are not used to limit the order or mutual dependence.

[0052] It should be noted that the "one", "multiple" modification mentioned in the present application is illustrative and not restrictive, and those skilled in the art should understand that unless the context clearly indicates otherwise, it should be understood as "one or more".

[0053] Figure 1 A structure diagram of a battery state detection system of an uninterruptible power supply provided by an embodiment of the present application is shown in Figure 1 The detection system includes an uninterruptible power supply module 10, a voltage sampling module 20, a current sampling module 30 and a processor 40. The first end of the voltage sampling module 20 is connected with the uninterruptible power supply module 10, for detecting the charging voltage of the uninterruptible power supply module 10, obtaining a voltage sampling signal, and the second end of the voltage sampling module 20 is connected with the processor 40. The first end of the current sampling module 30 is connected with the uninterruptible power supply module 10, for detecting the charging current of the uninterruptible power supply module 10, obtaining a current sampling signal, and the second end of the current sampling module 30 is connected with the processor 40. The processor 40 is used to determine the state of the uninterruptible power supply module 10 according to the voltage sampling signal and the current sampling signal.

[0054] Specifically, Figure 2 A structure diagram of another battery state detection system of an uninterruptible power supply provided by an embodiment of the present application is shown in Figure 2 The uninterruptible power supply module 10 includes a battery management unit 101, a charger circuit 102, an output capacitor 103 and a battery 104. The battery management unit 101 contains a switching power supply, which can convert alternating current into direct current input into the charger circuit 102 in the alternating current input mode. The charger circuit 102 includes two switching tubes Q1, Q2 and an inductor L1. Further, the charger circuit 102 converts the direct current into a charging voltage and a charging current matched with the battery 104, realizing the charging of the battery 104. Referring to Figure 2 The uninterruptible power supply module 10 further includes an output capacitor 103 connected in parallel with the battery 104, which can smooth and filter the voltage and current output by the charger circuit 102, ensuring the charging quality of the battery 104.

[0055] Furthermore, for most existing charger circuits 102, the charging process for battery 104 involves four stages: a pre-charge stage, a constant current stage, a constant voltage stage, and a termination stage. First, when charging begins, the charger circuit 102 pre-charges battery 104 with a small current. When the charging voltage of battery 104 rises to a certain threshold voltage V1, the charger circuit 102 enters the constant current stage, charging battery 104 with a constant current value. When the charging voltage of battery 104 rises again to a certain threshold voltage V2, the charger circuit 102 enters the constant voltage stage, charging battery 104 with a constant voltage value. It is understandable that when the charger circuit 102 enters the constant voltage stage to charge battery 104, the charging current decreases as battery 104 gradually approaches full charge. Therefore, when the charging current falls below a certain current threshold, the charger circuit 102 determines that battery 104 is fully charged and enters the termination stage, stopping charging battery 104. Furthermore, after battery 104 is fully charged, charger circuit 102 will continuously monitor the voltage of battery 104 to determine whether battery 104 is low on power. When the voltage of battery 104 drops to a certain threshold voltage V3, charger circuit 102 will restart charging battery 104 until the charging voltage rises to a certain threshold voltage V4, at which point charger circuit 102 will stop charging battery 104 again. <V3<V2<V4。

[0056] Based on this Figure 3 A waveform diagram of charging voltage and charging current provided for an embodiment of the present invention, as shown below. Figure 2 and Figure 3 As shown, when battery 104 is not missing, i.e., during the period between t0 and t1, charger circuit 102 charges battery 104 in a constant current manner. At time t1, charger circuit 102 enters the constant voltage stage. During the period between t1 and t2, due to the characteristics of battery 104 itself, the charging voltage has a small ripple. During the switching phase between starting and stopping charging, the charging voltage will have a noticeable fluctuation, but the duration is short, and misjudgment can be avoided by multiple samplings. At time t2, when battery 104 is missing, charger circuit 102 will continue to provide charging voltage, but due to the absence of battery 104, the charging voltage will quickly rise to the threshold voltage V4 for stopping charging. At the same time, due to the presence of output capacitor 103, the charging voltage will slowly drop to the threshold voltage V3. Then charger circuit 102 will start charging again, and the charging voltage will quickly rise to the threshold voltage V4 again. This cycle repeats, resulting in large fluctuations in the charging voltage when battery 104 is missing. Therefore, the state of battery 104 can be determined by detecting the changes in charging voltage and charging current at the output of charger circuit 102.

[0057] Further, referring to Figure 1 and Figure 2 , the detection system comprises a voltage sampling module 20 for detecting the charging voltage of the uninterruptible power supply module 10 to obtain a voltage sampling signal. The voltage sampling module 20 comprises a voltage dividing circuit composed of a resistor R2 and a resistor R4, a filter circuit composed of a capacitor C1 and the resistor R4, and a voltage follower U3A.

[0058] In particular, referring to Figure 2 , the resistor R2 and the resistor R4 are connected in series and then connected in parallel with the battery 104 for collecting the charging voltage. The capacitor C1 is connected in parallel with the resistor R4 to form a filter circuit with the resistor R4 for filtering out high-frequency noise in the charging voltage and reducing the influence of noise on the voltage sampling signal. Further, the voltage follower U3A is arranged between the voltage dividing circuit and the processor 40 to isolate the voltage dividing circuit from the processor 40, and the voltage follower U3A inputs the voltage sampling signal obtained by the voltage dividing circuit into the processor 40 to ensure the reliability of signal transmission.

[0059] Further, referring to Figure 1 and Figure 2 , the detection system comprises a current sampling module 30 for detecting the charging current of the uninterruptible power supply module 10 to obtain a current sampling signal. The current sampling module 30 comprises a sampling resistor R1 and an amplifier U2.

[0060] In particular, the sampling resistor R1 is connected in series between the charger circuit 102 and the battery 104 for detecting the charging current to obtain the current sampling signal. Further, the amplifier U2 is connected in parallel with the sampling resistor R1 to input the current sampling signal obtained by the sampling resistor R1 into the processor 40 after amplification, wherein the amplifier U2 has a high input impedance and a low output impedance, so as to reduce the interference of noise signals in the circuit during signal transmission.

[0061] Further, after the processor 40 obtains the voltage sampling signal and the current sampling signal, it can determine whether the battery 104 is missing according to the voltage sampling signal and the current sampling signal.

[0062] Further, the detection system further comprises a display unit, which will send the state information to the display unit after the processor 40 determines the state of the uninterruptible power supply module 10, so as to remind whether the battery 104 is missing. In addition, the processor 40 further comprises a memory, which can be used to store the missing result of the battery 104 for subsequent review and use.

[0063] The embodiment of the present application sets voltage sampling module and current sampling module between uninterruptible power supply module and processor, respectively detects charging voltage and charging current in the uninterruptible power supply module, obtains voltage sampling signal and current sampling signal, and further, processor can judge the missing state of the battery based on the difference of voltage sampling signal and current sampling signal under the state of battery missing and not missing, which reduces the complexity of the detection system and makes the detection method more simple and reliable.

[0064] Figure 4 A flowchart of the detection method of the battery state of the uninterruptible power supply provided by the embodiment of the present application is shown in the figure, the detection method is executed by the detection system of the battery state of the uninterruptible power supply described above, as shown in the figure, the detection method comprises the following steps. Figure 4

[0065] S101, obtaining the current sampling signal detected by the current sampling module.

[0066] Specifically, referring to the figures, Figure 1 and Figure 2 , the first end of the current sampling module 30 is connected with the uninterruptible power supply module 10, which is used for detecting the charging current in the uninterruptible power supply module 10 and obtaining the current sampling signal, and the second end of the current sampling module 30 is connected with the processor 40, so as to input the current sampling signal into the processor 40. Referring to the figure, Figure 3 , during the charging process of the battery 104 by the charger circuit 102 in the uninterruptible power supply module 10, the current sampling module 30 can detect a large and continuous charging current, as shown in the period between t0 and t1 in the figure. Figure 3 When the battery 104 is full or missing, the current sampling module 30 will detect a small charging current.

[0067] S102, obtaining the voltage sampling signal detected by the voltage sampling module.

[0068] Specifically, referring to the figures, Figure 1 and Figure 2 , the first end of the voltage sampling module 20 is connected with the uninterruptible power supply module 10, which is used for detecting the charging voltage in the uninterruptible power supply module 10 and obtaining the voltage sampling signal, and the second end of the voltage sampling module 20 is connected with the processor 40, so as to input the voltage sampling signal into the processor 40. Referring to the figure, Figure 3 , during the charging process of the battery 104 by the charger circuit 102 in the uninterruptible power supply module 10, due to the characteristics of the battery 104 itself, the charging voltage detected by the voltage sampling module 20 will have a small ripple, as shown in the period between t1 and t2 in the figure. Figure 3 When the battery 104 is missing, the charging voltage detected by the voltage sampling module 20 will have obvious up and down processes, as shown in the figure. Figure 3 ​The time period between t2 and t4 is shown.

[0069] S103, judging the battery missing state according to the current sampling signal and the voltage sampling signal.

[0070] Specifically, referring to Figure 3 Since the waveforms corresponding to the current sampling signal and the voltage sampling signal are obviously different when the battery 104 is missing and not missing, after the processor 40 receives the current sampling signal and the voltage sampling signal, the missing state of the battery 104 can be judged accordingly.

[0071] The embodiment of the application sets voltage sampling modules and current sampling modules between the uninterruptible power supply module and the processor, respectively detects the charging voltage and the charging current in the uninterruptible power supply module, obtains the voltage sampling signal and the current sampling signal, and further judges the missing state of the battery based on the difference between the voltage sampling signal and the current sampling signal when the battery is missing and not missing. Without any start-stop operation of the charging circuit, the system interference and stability problems caused by the detection process are avoided, the difference between the normal saturation of the battery and the missing of the battery can be effectively distinguished, the misjudgment risk generated at the end of the battery charging is avoided, and the accuracy of the judgment result is improved.

[0072] Optionally, Figure 5 Another flowchart of the detection method of the battery state of the uninterruptible power supply provided by the embodiment of the application is provided, and the embodiment is a refinement based on the above embodiment. Specifically, for step S103: judging the battery missing state according to the current sampling signal and the voltage sampling signal, it can be refined as:

[0073] When the current sampling signal is less than or equal to the preset current threshold, the minimum value of the voltage sampling signal in the preset time interval is found at a preset time interval as a period to obtain the sampling voltage minimum value.

[0074] When the sampling voltage minimum values found continuously for the first preset number of times are all less than or equal to the preset voltage threshold, it is determined that the battery is missing.

[0075] The parts of the embodiment not yet described are referred to the foregoing embodiments. As Figure 5 The detection method provided by the embodiment includes:

[0076] S201, obtaining the current sampling signal detected by the current sampling module.

[0077] S202, obtaining the voltage sampling signal detected by the voltage sampling module

[0078] S203. When the current sampling signal is less than or equal to the preset current threshold, find the minimum value of the voltage sampling signal within the preset time interval using a preset time interval as the period, and obtain the minimum value of the sampled voltage.

[0079] Specifically, refer to Figure 2 and Figure 3 When battery 104 is not missing, during the charging process of charger circuit 102 to battery 104, such as Figure 3 During the period between t0 and t1, the charger circuit 102 is in the constant current stage, during which the current sampling module 30 will detect a large and continuous charging current. At time t1, the charger circuit 102 enters the constant voltage stage, and the battery 104 gradually approaches a fully charged state, with the charging current gradually decreasing. It is understood that if the battery 104 is missing, the current sampling module 30 will also detect a small charging current. Therefore, when the current sampling signal obtained by the current sampling module 30 is less than or equal to a preset current threshold, it indicates that the battery 104 is either not missing and fully charged or missing. The slow charging current after the battery 104 is fully charged can be used as the preset current threshold. For example, for a 20Ah battery pack, the preset current threshold can be 0.5A.

[0080] To further determine the condition of battery 104, continue to refer to... Figure 2 and Figure 3 If battery 104 is missing at time t2, the charging voltage detected by voltage sampling module 20 will experience undershoot and overshoot due to the presence of output capacitor 103. Figure 3 The time interval between t2 and t3 is used as a preset time interval to find the minimum value of the voltage sampling signal within that preset time interval, thus obtaining the minimum value of the sampled voltage. The preset time interval needs to cover the process where the charging voltage drops to its minimum value due to the output capacitor 103 after the battery 104 is missing, and then charging resumes. Figure 3 During the period between t2 and t3, the cycle of the charging voltage down-stroke and up-stroke depends on the size of the output capacitor 103.

[0081] In an optional embodiment, before detecting the battery status of an uninterruptible power supply (UPS) module using the UPS battery status detection method provided in this embodiment of the invention, a preset time interval needs to be tested first to improve the accuracy of the detection method. That is, before acquiring the current sampling signal detected by the current sampling module, the method further includes actively controlling the UPS module to be in a battery-deficient state; acquiring the voltage sampling signal detected by the voltage sampling module; and determining the preset time interval based on the voltage sampling signal.

[0082] Specifically, refer to Figure 2 and Figure 3Because when battery 104 is missing, the charging voltage in uninterruptible power supply module 10 will exhibit the following characteristics: Figure 3 The waveform shown between t2 and t3 indicates that the active control uninterruptible power supply module 10 is in a state where the battery 104 is missing. Then, the voltage sampling module 20 detects the charging voltage and obtains the voltage sampling signal. Furthermore, the processor 40 can determine the time interval between t2 and t3 based on the voltage sampling signal, and then determine the preset time interval.

[0083] S204. When the minimum value of the sampled voltage found in the first preset number of consecutive searches is less than or equal to the preset voltage threshold, it is determined that the battery is missing.

[0084] Specifically, refer to Figure 3 When battery 104 is not missing, the charging voltage has a small ripple voltage. Therefore, battery 104 may only be missing if the minimum value of the sampled voltage is less than or equal to the preset voltage threshold. Furthermore, to avoid misjudgment caused by fluctuations in charging current and charging voltage due to normal switching during charging, battery 101 is determined to be missing only if the minimum value of the sampled voltage found in the first preset number of consecutive searches is less than or equal to the preset voltage threshold.

[0085] For example, refer to Figure 3 If the preset time interval is the time interval between t2 and t3, then when searching for the minimum value of the voltage sampling signal within the preset time interval with the preset time interval as the period, during the period when the battery is missing between t2 and t4, two consecutive cases can be found where the minimum value of the sampled voltage is less than the preset voltage threshold. However, at the time after t4, since battery 104 is not missing, the minimum value of the sampled voltage found within the preset time interval will be greater than the preset voltage threshold.

[0086] Based on this, in order to achieve the condition that the minimum value of the sampled voltage found in a consecutive first preset number of times is less than or equal to the preset voltage threshold, in an optional embodiment, when the minimum value of the sampled voltage is less than or equal to the preset voltage threshold, the first cumulative number is incremented by one; when the minimum value of the sampled voltage is greater than the preset voltage threshold, the first cumulative number is cleared to zero, until the first cumulative number is equal to the first preset number, at which point the battery is determined to be missing.

[0087] Specifically, refer to Figure 3When the charging current is less than the preset current threshold, the minimum value of the voltage sampling signal in the preset time interval is found periodically at preset time intervals, and the sampling voltage minimum value is obtained. Before the t2 moment, the sampling voltage minimum value is greater than the preset voltage threshold. At the t2 moment, the battery 104 is missing, so the sampling voltage minimum value found between t2 and t3 will be less than or equal to the preset voltage threshold, at which time the first cumulative number can be incremented by one. Further, between t3 and t4, the sampling voltage minimum value found will also be less than or equal to the preset voltage threshold, at which time the first cumulative number is incremented by one again. At the t4 moment, the battery 104 is connected, and the sampling voltage minimum value found will be greater than the preset voltage threshold, at which time the first cumulative number is cleared, and when the first cumulative number is equal to the first preset number, the battery 104 is determined to be missing. The first preset number is a number that can avoid misjudgment caused by the jitter of the charging current and the charging voltage due to the normal switching of the charging process, and the specific value can be set according to the actual situation.

[0088] The embodiment of the application improves the reliability of the judgment result by using the composite judgment method of the charging current and the charging voltage, and reduces the misjudgment caused by the jitter of the charging current and the charging voltage due to the normal switching of the charging process by comparing the sampling voltage minimum value with the preset voltage threshold multiple times and then determining the battery state, thereby improving the accuracy of the judgment result.

[0089] Optionally, Figure 6 A flowchart of another uninterrupted power supply battery state detection method provided by the embodiment of the application is provided, and the embodiment is a refinement based on the above embodiment. Specifically, in step S203, when the current sampling signal is less than or equal to the preset current threshold, the minimum value of the voltage sampling signal in the preset time interval is found periodically at preset time intervals, and the following steps are added while obtaining the sampling voltage minimum value:

[0090] When the current sampling signal collected continuously for the second preset number of times is greater than the preset current threshold, it is determined that the battery is not missing, and the voltage sampling signal is stopped.

[0091] The parts of the embodiment that have not been described in detail refer to the foregoing embodiments. As shown in the foregoing embodiments, Figure 6 The detection method provided by the embodiment includes:

[0092] S301, obtaining the current sampling signal detected by the current sampling module.

[0093] S302, obtaining the voltage sampling signal detected by the voltage sampling module.

[0094] S303, when the current sampling signal is less than or equal to the preset current threshold, periodically searching for the minimum value of the voltage sampling signal in the preset time interval to obtain the sampling voltage minimum value.

[0095] S304, when the sampling voltage minimum values searched for in the first preset number of times continuously are all less than or equal to the preset voltage threshold, determining that the battery is missing.

[0096] S305, when the current sampling signals collected in the second preset number of times continuously are all greater than the preset current threshold, determining that the battery is not missing, and stopping obtaining the voltage sampling signal.

[0097] Specifically, referring to Figure 2 and Figure 3 , since the current sampling module 30 can only detect the large and continuous charging current, i.e. Figure 3 the current between t0 and t1 in the period when the charger circuit 102 is charging the battery 104, further, since the charging current will also have the process of overshoot and undershoot when the battery 104 is missing, in order to improve the accuracy of the judgment result, when the processor 40 periodically searches for the minimum value of the voltage sampling signal in the preset time interval to judge the state of the battery 104, only when the current sampling signals collected in the second preset number of times continuously are all greater than the preset current threshold, it can be determined that the battery 104 is not missing, and the voltage sampling signal is stopped.

[0098] In an optional embodiment, when the current sampling signal is greater than the preset current threshold, the second cumulative number is increased by one, when the current sampling signal is less than or equal to the preset current threshold, the second cumulative number is cleared, and when the second cumulative number is equal to the second preset number, it is determined that the battery is not missing.

[0099] Specifically, since the charging current will also have the process of overshoot when the battery 104 is missing, so that the current sampling signal is greater than the preset current threshold at a certain moment, in order to improve the accuracy of the result of judging that the battery 104 is not missing, when the current sampling signal is greater than the preset current threshold, the second cumulative number is increased by one, when the current sampling signal is less than or equal to the preset current threshold, the second cumulative number is cleared, and when the second cumulative number is equal to the second preset number, it is determined that the battery 104 is not missing. In this way, false judgment caused by the overshoot of the charging current when the battery 104 is missing is avoided.

[0100] The embodiment of the present application further combines the current sampling signal and the voltage sampling signal, continuously detects the charging current while the processor judges the battery state according to the voltage sampling signal, and determines that the battery is in the non-loss state and stops acquiring the voltage sampling signal when the charging current continuously exceeds the preset current threshold, thereby reducing the calculation consumption of the processor, ensuring the timeliness and reliability of the judgment, and improving the accuracy of the judgment result.

[0101] Optionally, Figure 7 A flowchart of another uninterrupted power supply battery state detection method provided by the embodiment of the present application is shown, and the embodiment is a refinement based on the above embodiment. Specifically, step S103, judging the battery loss state according to the current sampling signal and the voltage sampling signal, can be further refined as follows.

[0102] According to the current sampling signal and the voltage sampling signal, the instantaneous charging power is calculated.

[0103] The absolute value of the difference between the previous instantaneous charging power and the next instantaneous charging power is calculated.

[0104] The sum of all absolute values in the preset time interval is calculated to obtain the instantaneous power change value.

[0105] When the instantaneous power change values calculated for the third preset number of times are all greater than or equal to the preset power change threshold, it is determined that the battery is lost.

[0106] The parts not yet described in the embodiment can be referred to the foregoing embodiments. As shown in the foregoing embodiments, Figure 7 The detection method provided by the embodiment includes:

[0107] S401, acquiring the current sampling signal detected by the current sampling module.

[0108] S402, acquiring the voltage sampling signal detected by the voltage sampling module.

[0109] S403, calculating the instantaneous charging power according to the current sampling signal and the voltage sampling signal.

[0110] Specifically, after the current sampling signal detected by the current sampling module 30 and the voltage sampling signal detected by the voltage sampling module 20 are acquired, the instantaneous charging power of the uninterrupted power supply module 10 can be calculated. Figure 8 A waveform diagram of the instantaneous charging power provided by the embodiment of the present application is shown. Figure 8As shown, before the time t2, the battery 104 is not missing, and after the time t2, the battery 104 is missing. It can be seen that the instantaneous charging power has different rates of change in the battery 104 missing and not missing states, that is, when the battery 104 is not missing, the instantaneous charging power changes more gently, and when the battery 104 is missing, the instantaneous charging power changes more quickly.

[0111] S404, calculate the absolute value of the difference between the previous and the next instantaneous charging power.

[0112] Specifically, after the processor 40 acquires the voltage sampling signal and the current sampling signal at the same sampling frequency and calculates the instantaneous charging power, the absolute value of the difference between the instantaneous charging power of the previous sampling point and the next sampling point can be further calculated. It can be understood that when the battery 104 is not missing, the instantaneous charging power changes slowly, and at this time the absolute value of the difference between the instantaneous charging power obtained is small, and when the battery 104 is missing, the instantaneous charging power changes quickly, and at this time the absolute value of the difference between the instantaneous charging power obtained is large.

[0113] S405, calculate the sum of all absolute values in a preset time interval as a cycle to obtain an instantaneous power change value.

[0114] Specifically, in order to improve the accuracy of the judgment result, the sum of all absolute values in a preset time interval is calculated as a cycle to obtain an instantaneous power change value. The preset time interval needs to cover the process of the charging voltage dropping to a minimum value due to the output capacitor 103 and then starting to charge again after the battery 104 is missing, that is, Figure 3 The period of the charging voltage drop and the charging voltage rise between t2 and t3 depends on the size of the output capacitor 103.

[0115] It can be understood that the preset time interval contains multiple sampling points of the charging current and the charging voltage, and therefore contains multiple calculated absolute values of the difference between the instantaneous charging power. Since the absolute value of the difference calculated when the battery is missing is greater than the absolute value of the difference obtained when the battery is not missing, the instantaneous power change value obtained by adding all the absolute values in the preset time interval will have a more obvious difference.

[0116] S406, when the instantaneous power change values calculated for a continuous third preset number of times are all greater than or equal to a preset power change threshold, it is determined that the battery is missing.

[0117] Specifically, an instantaneous power change value is obtained in each preset time interval, and when the instantaneous power change value is greater than or equal to a preset power change threshold, it indicates that the change range of the instantaneous charging power at this time is large. In order to avoid misjudgment caused by the jitter of the charging current and the charging voltage due to the normal switching in the charging process, only when the instantaneous power change values calculated for a continuous third preset number of times are all greater than or equal to the preset power change threshold, it is determined that the battery is missing.

[0118] In an optional embodiment, when the instantaneous power change value is greater than or equal to the preset power change threshold, the third cumulative number is incremented by one, and when the instantaneous power change value is less than the preset power change threshold, the third cumulative number is cleared, until the third cumulative number is equal to the third preset number, the battery is determined to be missing.

[0119] Specifically, referring to Figure 8 At t0, start to calculate the sum of all absolute values in a preset time interval periodically, and obtain an instantaneous power change value. Before t2, since the battery 104 is not missing, the instantaneous charging power changes slowly, so the obtained instantaneous power change value will be less than the preset power change threshold. At t2, since the battery 104 is missing, the instantaneous charging power changes rapidly, so the instantaneous power change value obtained between t2 and t3 will be greater than or equal to the preset power change threshold, and the third cumulative number is incremented by one at this time. Further, the instantaneous power change value obtained between t3 and t4 will also be greater than or equal to the preset power change threshold, and the third cumulative number is incremented by one again at this time. At t4, since the battery 104 is connected, the obtained instantaneous power change value will be less than the preset power change threshold, and the third cumulative number is cleared at this time, until the third cumulative number is equal to the third preset number, the battery 104 is determined to be missing. The third preset number is a number that can avoid misjudgment caused by the jitter of the charging current and the charging voltage due to the normal switching in the charging process, and the specific value can be set according to the actual situation.

[0120] The embodiment of the application integrates the instantaneous charging power calculated by the charging voltage and the charging current, avoids misjudgment caused by a single parameter, improves the accuracy of the judgment result, and is suitable for battery online state detection of most charging circuits. At the same time, it does not need to start and stop the charging circuit, and avoids interference to the charging circuit.

[0121] Optionally, Figure 9 A flowchart of another battery state detection method of an uninterruptible power supply provided by the embodiment of the application is provided, and the embodiment is a refinement based on the above-mentioned embodiment. Specifically, before step S103, the following steps are added before judging the battery missing state according to the current sampling signal and the voltage sampling signal:

[0122] analog-to-digital conversion is performed on the current sampling signal and the voltage sampling signal.

[0123] filtering is performed on the current sampling signal and the voltage sampling signal.

[0124] The parts of the present embodiment not described in detail can refer to the foregoing embodiments. Figure 9 As shown in the present embodiment, the detection method provided by the present embodiment comprises:

[0125] S501, obtaining a current sampling signal detected by a current sampling module.

[0126] S502, obtaining a voltage sampling signal detected by a voltage sampling module.

[0127] S503, performing analog-to-digital conversion on the current sampling signal and the voltage sampling signal.

[0128] Specifically, the processor 40 comprises an analog-to-digital converter, after the processor 40 obtains the current sampling signal and the voltage sampling signal, the analog-to-digital converter first performs analog-to-digital conversion on the current sampling signal and the voltage sampling signal, so that the processor 40 can make a judgment based on the current sampling signal and the voltage sampling signal.

[0129] S504, filtering is performed on the current sampling signal and the voltage sampling signal.

[0130] Specifically, the processor 40 further comprises a filter, after the filter receives the current sampling signal and the voltage sampling signal after analog-to-digital conversion, it further filters them to remove high-frequency noise and improve the accuracy of data. Exemplarily, it can be median filtering.

[0131] S505, judging a battery missing state according to the current sampling signal and the voltage sampling signal.

[0132] The present embodiment further improves the accuracy of the judgment result by pre-processing the current sampling signal and the voltage sampling signal.

[0133] Note that the above are only preferred embodiments of the present application and the technical principles applied. Those skilled in the art will understand that the present application is not limited to the specific embodiments described herein, and those skilled in the art can make various obvious changes, re-adjustments, mutual combinations and substitutions without departing from the scope of the present application. Therefore, although the present application has been described in more detail through the above embodiments, the present application is not limited to the above embodiments, and can include more other equivalent embodiments without departing from the concept of the present application, and the scope of the present application is determined by the scope of the appended claims.

Claims

1. A method for detecting the state of an uninterruptible power supply battery, characterized in that, The detection is performed using an uninterruptible power supply (UPS) battery status detection system, which includes a UPS module, a voltage sampling module, and a current sampling module; the first terminal of the voltage sampling module is connected to the UPS module, and the first terminal of the current sampling module is also connected to the UPS module. The detection method includes: Obtain the current sampling signal detected by the current sampling module; The voltage sampling signal detected by the voltage sampling module is acquired; The battery missing status is determined based on the current sampling signal and the voltage sampling signal.

2. The method according to claim 1, characterized in that, Determining the battery missing state based on the current sampling signal and the voltage sampling signal includes: When the current sampling signal is less than or equal to a preset current threshold, the minimum value of the voltage sampling signal within the preset time interval is found to obtain the minimum value of the sampled voltage. If the minimum value of the sampled voltage found in a first preset number of consecutive searches is less than or equal to a preset voltage threshold, the battery is determined to be missing.

3. The method according to claim 2, characterized in that, When the minimum value of the sampled voltage found in a first preset number of consecutive searches is less than or equal to a preset voltage threshold, it is determined that the battery is missing, including: When the minimum value of the sampled voltage is less than or equal to the preset voltage threshold, the first cumulative count is incremented by one; when the minimum value of the sampled voltage is greater than the preset voltage threshold, the first cumulative count is reset to zero, until the first cumulative count equals the first preset count, at which point the battery is determined to be missing.

4. The method according to claim 2, characterized in that, When the current sampling signal is less than or equal to a preset current threshold, the minimum value of the voltage sampling signal within the preset time interval is searched at a preset time interval. In addition to obtaining the minimum value of the sampled voltage, the method also includes: If the current sampling signal collected for a second consecutive preset number of times is greater than the preset current threshold, it is determined that the battery is not missing, and the acquisition of the voltage sampling signal is stopped.

5. The method according to claim 4, characterized in that, When the current sampling signal collected for a second consecutive preset number of times is greater than the preset current threshold, it is determined that the battery is not missing, including: When the current sampling signal is greater than the preset current threshold, the second cumulative count is incremented by one; when the current sampling signal is less than or equal to the preset current threshold, the second cumulative count is cleared to zero, until the second cumulative count equals the second preset count, at which point it is determined that the battery is not missing.

6. The method according to claim 1, characterized in that, Determining the battery missing state based on the current sampling signal and the voltage sampling signal includes: The instantaneous charging power is calculated based on the current sampling signal and the voltage sampling signal; Calculate the absolute value of the difference between the instantaneous charging power described in the previous step and the instantaneous charging power described in the next step; Using a preset time interval as the period, calculate the sum of all the absolute values ​​within the preset time interval to obtain the instantaneous power change value; If the instantaneous power change value calculated for a third consecutive preset number of times is greater than or equal to a preset power change threshold, the battery is determined to be missing.

7. The method according to claim 6, characterized in that, When the instantaneous power change value calculated for a third consecutive preset number of times is greater than or equal to a preset power change threshold, the battery is determined to be missing, including: When the instantaneous power change value is greater than or equal to the preset power change threshold, the third cumulative count is incremented by one; when the instantaneous power change value is less than the preset power change threshold, the third cumulative count is reset to zero, until the third cumulative count equals the third preset count, thus determining that the battery is missing.

8. The method according to claim 2 or 6, characterized in that, Before acquiring the current sampling signal detected by the current sampling module, the method further includes: Actively control the uninterruptible power supply module to a battery-deficient state; The voltage sampling signal detected by the voltage sampling module is acquired; The preset time interval is determined based on the voltage sampling signal.

9. The method according to claim 1, characterized in that, Before determining the battery missing state based on the current sampling signal and the voltage sampling signal, the process further includes: The current sampling signal and the voltage sampling signal are subjected to analog-to-digital conversion; The current sampling signal and the voltage sampling signal are filtered.

10. A system for detecting the state of an uninterruptible power supply (UPS) battery, used to perform the method for detecting the state of a UPS battery as described in any one of claims 1-9; the detection system includes a UPS module, a voltage sampling module, a current sampling module, and a processor; The first terminal of the voltage sampling module is connected to the uninterruptible power supply module and is used to detect the charging voltage of the uninterruptible power supply module and obtain a voltage sampling signal. The second terminal of the voltage sampling module is connected to the processor. The first terminal of the current sampling module is connected to the uninterruptible power supply module and is used to detect the charging current of the uninterruptible power supply module and obtain a current sampling signal. The second terminal of the current sampling module is connected to the processor. The processor is used to determine the state of the uninterruptible power supply module based on the voltage sampling signal and the current sampling signal.

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