Backup power supply charging and diagnosis management system and method

Abstract

The invention provides a backup power supply charging and diagnosis management system and method, and relates to the field of wind driven generator control systems.The backup power supply charging and diagnosis management system comprises a rectifier, a backup power supply, a circuit control module and a controller, and the rectifier is used for rectifying alternating current into direct current and transmitting the direct current to the circuit control module; the circuit control module is used for acquiring the dispatching instruction and changing the control switch combination based on the control instruction so as to limit the charging current and the discharging current of the back-up power supply; the backup power supply is used for storing the current or outputting the stored current; and the controller is used for acquiring the control instruction, the state data of the back-up power supply and the state data of the circuit control module in real time, and performing abnormity diagnosis and charging control on the back-up power supply by generating a scheduling instruction of the circuit control module in combination with a preset charging trigger condition. The reliability of the backup power supply system can be improved, and the operation and maintenance difficulty is reduced.

Description

Technical Field

[0001] This invention relates to the field of wind turbine control systems, and more particularly to a backup power charging and diagnostic management system and method. Background Technology

[0002] A wind turbine is an electrical device that converts wind energy into mechanical work, which drives a rotor to rotate and ultimately outputs alternating current. A wind turbine typically consists of components such as a wind turbine, generator, tower, speed-limiting safety mechanism, and energy storage device.

[0003] Backup power for wind turbines based on lead-acid batteries and supercapacitors is a widely used solution in the industry. The pitch system, as a crucial control and protection device for wind turbines, plays a vital role in blade control and wind energy capture. When a wind turbine malfunctions, the pitch system must control the blades to retract to a safe position, achieving air braking, which is the most critical safety feature of the wind turbine. In the event of grid power anomalies, the pitch system needs to utilize the turbine's backup power supply to provide energy for the retraction function. With the rapid development of the wind power industry, the reliability and stability of the pitch system's backup power supply, as a crucial component of wind turbines, have received widespread attention.

[0004] Currently, to address the issues of backup power charging and circuit anomaly detection in wind turbine generators, battery management systems (BMS) have been introduced into the charging and discharging processes of lead-acid batteries. BMS can effectively control the charging and discharging processes of lead-acid batteries, preventing overcharging and over-discharging, and monitoring various parameters of the backup power supply in real time to ensure its safe operation.

[0005] The backup power system for wind turbines mainly consists of lead-acid batteries and supercapacitors. Backup power charging and anomaly detection are handled by battery chargers and supercapacitor chargers. Charging is achieved by controlling the charger's output voltage and current, such as constant current charging, constant voltage charging, or a combination of constant current and constant voltage charging. Anomaly detection is achieved by detecting the backup power supply terminal voltage and charging current, including circuit anomaly and functional anomaly detection. For example, in charging circuit open-circuit detection, when an open circuit occurs, current cannot flow, and the charger detects zero charging current, indicating an open circuit. This approach has the following main disadvantages: high cost and complex fault handling. It requires a high-power battery management system or charger, resulting in high economic costs. After charger or other equipment failures, there is a high dependence on spare parts, and fault handling is difficult and timely.

[0006] No effective solutions have yet been proposed to address the problems in the relevant technologies. Summary of the Invention

[0007] In view of this, the present invention provides a backup power charging and diagnostic management system and method to solve the aforementioned problems.

[0008] To solve the above problems, the specific technical solution adopted by the present invention is as follows:

[0009] According to one aspect of the present invention, a backup power charging and diagnostic management system is provided, comprising: a rectifier, a backup power supply, a circuit control module and a controller, wherein the rectifier, the circuit control module and the backup power supply are sequentially connected to the controller;

[0010] A rectifier is used to rectify alternating current into direct current and then deliver the direct current to the circuit control module.

[0011] The circuit control module is used to acquire scheduling instructions and change the control switch combination based on the control instructions to limit the charging current and discharging current of the backup power supply.

[0012] Backup power supply, used to store current or output the stored current;

[0013] The controller is used to acquire control commands, backup power status data, and circuit control module status data in real time. Combined with preset charging trigger conditions, it generates scheduling commands for the circuit control module to perform anomaly diagnosis and charging control for the backup power.

[0014] Preferably, the circuit control module includes: resistor R1, resistor R2, resistor R3, controllable switch K1, controllable switch K2, controllable switch K3 and controllable switch K4;

[0015] One end of the controllable switch K1 is connected to the rectifier, and the other end of the controllable switch K1 is connected in series with one end of the resistor R1 and in parallel with the controllable switch K2 and the resistor R2; the other end of the resistor R1 is connected in series with one end of the resistor R3, and the other end of the resistor R3 is connected to one end of the controllable switch K4. The controllable switch K3 is connected in parallel across the two ends of the resistor R3, and the two ends of the controllable switch K4 are connected to the positive and negative terminals of the backup power supply, respectively; the controllable switch K2 and the resistor R2 are connected in parallel across the two ends of the resistor R1.

[0016] Preferably, one end of the rectifier is connected to the three-phase AC power supply of the mains via a controllable switch Km.

[0017] Preferably, the limiting of the charging current and discharging current of the backup power supply includes: fast charging current, float charging current, fast discharging current, slow discharging current, and charging stop current.

[0018] The expression for fast charging current is:

[0019] ;

[0020] The expression for the float charge current is:

[0021] ;

[0022] The expression for the rapid discharge current is:

[0023] ;

[0024] The expression for slow discharge current is:

[0025] ;

[0026] The expression for the stopping charging current is:

[0027] ;

[0028] In the formula, i 快充 Indicates the fast charging current, i 慢充 Indicates the float charge current, i 快放 Indicates the rapid discharge current, i 慢放 Indicates the slow discharge current, i 停止 Indicates the stopping charging current, u DC U represents the rectifier output voltage. backup R represents the backup power supply terminal voltage. in R1 represents the internal resistance of the backup power supply, R2 represents the resistance value of resistor R2, and R3 represents the resistance value of resistor R3.

[0029] Preferably, real-time acquisition of control commands, backup power supply status data, and circuit control module status data, combined with preset charging trigger conditions, generates scheduling commands for the circuit control module to perform anomaly diagnosis and charging control for the backup power supply, including:

[0030] The system acquires control commands, backup power status data, and circuit control module status data in real time. Control commands include diagnostic commands and charging commands. Backup power status data includes voltage data and charging time. Circuit control module status data consists of feedback signals from controllable switches Km, K1, K2, K3, and K4.

[0031] When the control command is a diagnostic command, the voltage data of the backup power supply is denoised. Based on the denoised voltage data, combined with the charging time and circuit control module status data, the backup power supply is diagnosed as abnormal.

[0032] When the control command is a charging command, the voltage data of the backup power supply is denoised. Based on the denoised voltage data, it is determined whether the backup power supply meets the preset charging trigger conditions. If it does, a control command is generated from the circuit control module to control the controllable switch state.

[0033] Preferably, the noise reduction process for the backup power supply voltage data includes the following steps:

[0034] The voltage timing signal of the backup power supply voltage data is converted and processed, and polar coordinate encoding is used to convert the voltage timing signal into a two-dimensional image matrix;

[0035] Based on a pre-defined lightweight U-Net network, the two-dimensional image matrix is ​​encoded and decoded, and multi-scale feature maps are extracted.

[0036] Based on the characteristic that pixel values ​​in similar regions should be similar, noise reduction processing is performed on multi-scale feature maps to obtain a noise-reduced two-dimensional image;

[0037] One-dimensional voltage time-series inverse mapping is performed on the denoised two-dimensional image to obtain the denoised voltage data.

[0038] Preferably, the voltage timing signal of the backup power supply voltage data is converted and processed by polar coordinate encoding to convert the voltage timing signal into a two-dimensional image matrix, including the following steps:

[0039] The voltage timing signal of the backup power supply voltage data is normalized, and the voltage timing signal value is mapped to a preset angle range and radius range to obtain the mapping result;

[0040] Based on the mapping results, the image pixel values ​​are constructed using the Gramian angular field formula, and the temporal correlation between any two time points is encoded to obtain a two-dimensional image matrix.

[0041] Preferably, the denoised two-dimensional image is subjected to one-dimensional voltage time-series inverse mapping processing to obtain denoised voltage data including:

[0042] Extract the main diagonal elements from the denoised 2D image;

[0043] Based on the main diagonal elements, the reverse formula is used to map the denoised two-dimensional image to a voltage time series, thus obtaining the denoised voltage data.

[0044] Preferably, the abnormal diagnosis of the backup power supply includes: fast charging timeout abnormality, control signal execution abnormality, backup power supply voltage over-limit abnormality, and voltage curve abnormality;

[0045] Fast charging timeout error occurs when the fast charging time exceeds the preset charging time during the fast charging phase.

[0046] An abnormal control signal execution is diagnosed when the feedback signals of controllable switches Km, K1, K2, K3, and K4 are inconsistent with the control commands.

[0047] The backup power supply voltage exceeds the limit abnormality. This is diagnosed when the voltage data after noise reduction is higher than the upper limit of the backup power supply voltage.

[0048] If the voltage curve is abnormal, during the charging phase, a standard charging time-theoretical voltage curve for fast charging and float charging is established based on the voltage data after noise reduction. The charging voltage of the backup power supply is evaluated in real time. When the evaluation result is greater than the preset threshold, it is diagnosed as an abnormal voltage curve.

[0049] Preferably, during the charging phase, based on the voltage data after noise reduction and post-processing, a standard charging time-theoretical voltage curve for fast charging and float charging is established, and the charging voltage of the backup power supply is evaluated in real time. When the evaluation result exceeds a preset threshold, an abnormal voltage curve is diagnosed, including:

[0050] During the charging phase, standard charging time-theoretical voltage curves for fast charging and float charging are established based on the characteristics of the backup power supply.

[0051] Outlier identification and removal are performed on the denoised voltage data to obtain voltage data that conforms to the physical laws of charging.

[0052] Based on the standard charging time-theoretical voltage curves of fast charging and float charging, the root mean square error method is used to evaluate the voltage data that conforms to the physical laws of charging in real time, and the evaluation results are obtained.

[0053] The evaluation result is compared with a preset threshold. If the evaluation result is greater than the preset threshold, the voltage curve is judged to be abnormal.

[0054] Preferably, controlling the state of the controllable switch includes:

[0055] Under fast charging conditions, the controllable switch is controlled as follows: controllable switch Km is closed, controllable switch K1 is closed, controllable switch K2 is open, and controllable switch K3 is closed.

[0056] Under float charging conditions, the controllable switch is controlled as follows: controllable switch Km is closed, controllable switch K1 is closed, controllable switch K2 is open, and controllable switch K3 is open.

[0057] Under rapid discharge conditions, the controllable switch is controlled in the following ways: controllable switch Km is open, controllable switch K1 is open, controllable switch K2 is closed, and controllable switch K3 is closed.

[0058] Under slow discharge conditions, the controllable switch control modes are: controllable switch Km open, controllable switch K1 open, controllable switch K2 closed, and controllable switch K3 open.

[0059] When charging is stopped, the controllable switch is controlled as follows: controllable switch Km is closed, controllable switch K1 is open, controllable switch K2 is open, and controllable switch K3 is open.

[0060] According to another aspect of the present invention, a backup power charging and diagnostic management method is provided, the method comprising the following steps:

[0061] The alternating current is rectified into direct current using a rectifier, and the direct current is then delivered to the circuit control module.

[0062] The circuit control module obtains scheduling instructions and changes the control switch combination based on the control instructions to limit the charging current and discharging current of the backup power supply.

[0063] Utilize backup power to store current or output the stored current;

[0064] The controller acquires control commands, backup power status data, and circuit control module status data in real time. Combined with preset charging trigger conditions, it generates scheduling commands for the circuit control module to perform anomaly diagnosis and charging control for the backup power.

[0065] The beneficial effects of this invention are as follows:

[0066] 1. This invention adopts a variable electrical topology and uses series resistors to limit current to achieve charging, discharging, and detection of backup power. The main electrical components are resistors and contactors. The components have high reliability and are not prone to failure. The system is simple and fault handling is convenient, which can improve the reliability of the backup power system and reduce the difficulty of operation and maintenance.

[0067] 2. The solution proposed in this invention eliminates the need for chargers, battery management systems, and other such devices. The main electrical components are resistors and contactors, resulting in lower component costs. The system circuitry is intuitive and clear, leading to high maintenance efficiency and low operating costs. This improves the economics of backup power systems. Attached Figure Description

[0068] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings:

[0069] Figure 1 This is an electrical topology diagram of a backup power charging and diagnostic management system according to an embodiment of the present invention;

[0070] Figure 2 This is a standard charging time-theoretical voltage curve in a backup power charging and diagnostic management system according to an embodiment of the present invention;

[0071] Figure 3 This is a schematic diagram of the backup power charging control process in a backup power charging and diagnostic management system according to an embodiment of the present invention.

[0072] Figure 4 This is a schematic diagram of the backup power supply anomaly detection process in a backup power supply charging and diagnostic management system according to an embodiment of the present invention.

[0073] Figure 5 This is a system key state response curve diagram of the float charging to stop charging stage in a backup power charging and diagnostic management system according to an embodiment of the present invention.

[0074] Figure 6 This is a system critical state response curve diagram during system anomaly detection in a backup power charging and diagnostic management system according to an embodiment of the present invention. Detailed Implementation

[0075] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this application.

[0076] According to embodiments of the present invention, a backup power charging and diagnostic management system and method are provided.

[0077] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments, such as... Figure 1As shown, according to an embodiment of the present invention, a backup power charging and diagnostic management system is provided, including: a rectifier, a backup power supply, a circuit control module, and a controller, wherein the rectifier, the circuit control module, and the backup power supply are sequentially connected to the controller; the rectifier is used to rectify AC power into DC power and deliver the DC power to the circuit control module; one end of the rectifier is connected to the three-phase AC power of the mains through a controllable switch Km. The circuit control module is used to acquire scheduling instructions and change the control switch combination based on the control instructions to limit the charging current and discharging current of the backup power supply; the backup power supply is used to store current or output the stored current; the controller is used to acquire control instructions, backup power supply status data, and circuit control module status data in real time, and, in conjunction with preset charging trigger conditions, generate scheduling instructions from the circuit control module to perform abnormal diagnosis and charging control of the backup power supply.

[0078] In a preferred embodiment, the circuit control module includes: resistors R1, R2, and R3; controllable switches K1, K2, K3, and K4; controllable switch Km, rectifier, controllable switch K1, resistors R1, R3, and K4, and backup power supply are connected in series to form a circuit. Resistors R1 and R3 are in the positive DC circuit. Controllable switch K2 has two channels: one channel is connected in parallel between the front end of the positive DC resistor R1 and the negative DC terminal; the other channel is connected in series with resistor R2 and then in parallel between the rear end of the positive DC resistor R1 and the negative DC terminal. Controllable switch K3 is connected in parallel with resistor R3.

[0079] Specifically, one end of the controllable switch K1 is connected to the rectifier, and the other end of the controllable switch K1 is connected in series with one end of the resistor R1 and in parallel with the controllable switch K2 and the resistor R2; the other end of the resistor R1 is connected in series with one end of the resistor R3, and the other end of the resistor R3 is connected to one end of the controllable switch K4; the controllable switch K3 is connected in parallel across the two ends of the resistor R3; the two ends of the controllable switch K4 are connected to the positive and negative terminals of the backup power supply, respectively; the controllable switch K2 and the resistor R2 are connected in parallel across the two ends of the resistor R1.

[0080] Specifically, the AC power ABC is rectified into DC power by a rectifier. Controllable switch Km is the main power supply control switch, controlling the AC input of the entire system. Controllable switches K1, K2, and K3 are electrical topology conversion control switches. By changing the combination of these switches, along with resistors R1, R2, and R3, the resistance values ​​of the charging and discharging circuits are altered, limiting the charging and discharging currents of the backup power supply and enabling rapid charging, float charging, rapid discharging, slow discharging, and charging cessation. Controllable switch K4 is the backup power supply switch, controlling the on / off state of the backup power supply circuit. In case of an abnormality in the charging circuit, disconnecting controllable switch K4 prevents over-discharge damage to the backup power supply. The controller input is the backup power supply voltage u. backup The system outputs control commands and feedback signals from controllable switches Km, K1, K2, K3, and K4, and the outputs control commands for controllable switches Km, K1, K2, K3, and K4.

[0081] The controller is the core device for state monitoring, calculation, and control. It controls the controllable switches Km, K1, K2, and K3 by monitoring the DC voltage and control commands in real time.

[0082] For topology control of fast charging, float charging, fast discharging, slow discharging, and charging stop, the controllable switches Km, K1, K2, and K3 are shown in Table 1, where 0 represents an open controllable switch and 1 represents a closed controllable switch.

[0083] Table 1 Control commands for controllable switches under different operating conditions

[0084] As a preferred embodiment, limiting the charging current and discharging current of the backup power supply includes: fast charging current, float charging current, fast discharging current, slow discharging current, and stop charging current.

[0085] The expression for fast charging current is:

[0086] ;

[0087] The expression for the float charge current is:

[0088] ;

[0089] The expression for the rapid discharge current is:

[0090] ;

[0091] The expression for slow discharge current is:

[0092] ;

[0093] The expression for the stopping charging current is:

[0094] ;

[0095] In the formula, i 快充 Indicates the fast charging current, i 慢充 Indicates the float charge current, i 快放 Indicates the rapid discharge current, i 慢放 Indicates the slow discharge current, i 停止 Indicates the stopping charging current, u DC U represents the rectifier output voltage. backup R represents the backup power supply terminal voltage. in R1 represents the internal resistance of the backup power supply, R2 represents the resistance value of resistor R2, and R3 represents the resistance value of resistor R3.

[0096] It should be noted that the backup power system charging control process is as follows: Figure 3 As shown, after the system is powered on, the controller monitors the backup power supply voltage u in real time. backup , if u backup Below fast charging voltage u quickcharge The system enters the fast charging phase; otherwise, the system skips fast charging. Then, if u... backup Below the float charge voltage u floatcharge And higher than the low-speed charging voltage u slowcharge The system enters the float charging phase; otherwise, the system jumps to the stop charging phase. Then, if u... backup Higher than u floatcharge The system jumps to the stop charging phase. Finally, if u backup Below fast charging voltage u quickcharge And the system showed no abnormalities, so it entered a new charging process.

[0097] Among them, the float charging voltage u floatcharge Based on the ambient temperature and backup power characteristics, the float charge voltage temperature compensation value ΔV is:

[0098] ΔV = (T - 25) × k × n;

[0099] In the formula, T is the ambient temperature, k is the float charge voltage temperature compensation coefficient, and n is the number of battery cells in the backup power supply.

[0100] In a preferred embodiment, real-time acquisition of control commands, backup power supply status data, and circuit control module status data, combined with preset charging trigger conditions, and generating scheduling commands for the circuit control module to perform anomaly diagnosis and charging control of the backup power supply includes: real-time acquisition of control commands, backup power supply status data, and circuit control module status data; control commands include diagnostic commands and charging commands; backup power supply status data includes voltage data and charging time; and circuit control module status data consists of feedback signals from controllable switches Km, K1, K2, K3, and K4; when the control command is a diagnostic command, the backup power supply voltage data is denoised; based on the denoised voltage data, combined with the charging time and circuit control module status data, anomaly diagnosis of the backup power supply is performed; when the control command is a charging command, the backup power supply voltage data is denoised; based on the denoised voltage data, it is determined whether the backup power supply meets the preset charging trigger conditions; if so, a control command for the circuit control module is generated to control the state of the controllable switches.

[0101] It should be noted that under fault-free system operation, there are two conditions that can meet the charging trigger condition: one is when the backup power supply voltage u backup Below fast charging voltage u quickcharge When the charging trigger condition is met; another is when the backup power supply voltage u backup Below the float charge voltage u floatcharge And higher than the low-speed charging voltage u slowcharge At that time, the charging trigger condition is met.

[0102] As a preferred embodiment, the denoising process for the backup power supply voltage data includes the following steps: converting the voltage time-series signal of the backup power supply voltage data into a two-dimensional image matrix using polar coordinate encoding; encoding-decoding the two-dimensional image matrix based on a preset lightweight U-Net network and extracting multi-scale feature maps; denoising the multi-scale feature maps based on the characteristic that pixel values ​​in similar regions should be similar to obtain a denoised two-dimensional image; and performing one-dimensional voltage time-series inverse mapping on the denoised two-dimensional image to obtain the denoised voltage data.

[0103] As a preferred embodiment, the voltage timing signal of the backup power supply voltage data is converted and processed, and the voltage timing signal is converted into a two-dimensional image matrix using polar coordinate encoding. This includes the following steps: normalizing the voltage timing signal of the backup power supply voltage data, mapping the voltage timing signal value to a preset angle range and radius range to obtain the mapping result; based on the mapping result, constructing image pixel values ​​using the Gramian angle field formula, and encoding the temporal correlation between any two moments to obtain a two-dimensional image matrix.

[0104] As a preferred embodiment, performing one-dimensional voltage time-series inverse mapping processing on the denoised two-dimensional image to obtain denoised voltage data includes: extracting the main diagonal elements from the denoised two-dimensional image; and mapping the denoised two-dimensional image to a voltage time-series based on the main diagonal elements using a reverse calculation formula to obtain denoised voltage data.

[0105] During system operation, the controller monitors the charging time, backup power supply voltage, controllable switch Km feedback signal, controllable switch K1 feedback signal, controllable switch K2 feedback signal, and controllable switch K3 feedback signal in real time.

[0106] To address the noise in the backup power supply voltage data, a one-dimensional voltage time-series denoising method based on two-dimensional image transformation is first employed. The specific method is as follows:

[0107] (1) For the backup power supply voltage timing signal u backup (t) (t=1,2,…,N), is converted into a two-dimensional image matrix through polar coordinate encoding. (M≤N, take the sliding window size), preserve the amplitude and phase correlation of the timing sequence:

[0108] Normalization: Mapping voltage values ​​to intervals [0,π] (angle) and [0,1] (radius):

[0109] ;

[0110] Two-dimensional matrix generation: Image pixel values ​​are constructed using the Gramian angular field formula to encode the temporal correlation between any two time points.

[0111] ;

[0112] (The matrix element values ​​reflect the coordinated voltage changes at times t=i and t=j, and noise appears in the image as isolated noise points or disordered textures.)

[0113] In the formula, u max U represents the theoretical maximum voltage. min Let θ(t) represent the theoretical minimum of voltage, ensuring that the angle is positively correlated with the time sequence position. Let t represent time, θ(t) represent the angle (in radians) mapped from the voltage value at time t, θ(i) represent the angle mapped from the voltage value at time i, θ(j) represent the angle mapped from the voltage value at time j, r(t) represent the normalized radius corresponding to time t (the normalized value reflecting the time sequence position), r(i) represent the normalized radius corresponding to time i, r(j) represent the normalized radius corresponding to time j, and G(i,j) represent the two-dimensional image matrix.

[0114] (2) Image feature-based noise reduction: Reusing spatial feature extraction and context association modeling techniques from the image domain to specifically suppress noise.

[0115] 1) Multi-scale CNN feature extraction;

[0116] Design a lightweight U-Net network to encode and decode a two-dimensional image G:

[0117] Encoding end: Spatial features at different scales (such as local voltage fluctuation texture and global trend contour) are extracted through 3 layers of convolution (3×3 convolution kernel), and noise corresponds to high-frequency weak features;

[0118] Decoding end: Introduce a temporal attention mechanism (associating convolution kernel weights with time window positions) to enhance the preservation of features at real voltage abrupt changes (such as a sudden voltage drop at the beginning of discharge) and suppress activation responses to random noise.

[0119] 2) Non-local mean (NLM) spatial filtering;

[0120] Secondary noise reduction is performed on the feature maps output by the CNN, taking advantage of the property that "similar regions in an image should have similar pixel values":

[0121] ;

[0122] In the formula, G denoise (x,y) represents the feature image after secondary denoising, Ω represents the neighborhood centered at (x,y), h represents the adaptive bandwidth, which is dynamically adjusted according to the local variance to ensure that the pixel values ​​of the real temporally correlated region are preserved; G(i,j) represents the two-dimensional image matrix, G(x,y) represents the pixel value at coordinate (x,y) in the feature image, and Z(x,y) represents the normalization coefficient, which is used to ensure the rationality of the filtered pixel values ​​and is calculated by the weights of all pixels in the neighborhood.

[0123] (3) Inverse mapping from two-dimensional images to one-dimensional voltage time series;

[0124] From the noise-reduced image G denoise Recovering a pure voltage signal :

[0125] 1) The main diagonal elements of the feature image after noise reduction (corresponding to voltage features at a single time step) are represented as follows:

[0126] ;

[0127] 2) Reverse angle And map it back to the voltage value:

[0128] ;

[0129] If the system experiences a fast charging timeout, control signal execution error, backup power supply voltage over-limit error, or voltage curve error during the fast charging or float charging phases, the system will directly enter the stop charging phase.

[0130] As a preferred embodiment, abnormal diagnosis of the backup power supply includes: fast charging timeout abnormality, control signal execution abnormality, backup power supply voltage over-limit abnormality, and voltage curve abnormality.

[0131] Fast charging timeout error occurs when the fast charging time exceeds the preset charging time during the fast charging phase.

[0132] An abnormal control signal execution is diagnosed when the feedback signals of controllable switches Km, K1, K2, K3, and K4 are inconsistent with the control commands.

[0133] The backup power supply voltage exceeds the limit abnormality. This is diagnosed when the voltage data after noise reduction is higher than the upper limit of the backup power supply voltage.

[0134] If the voltage curve is abnormal, during the charging phase, a standard charging time-theoretical voltage curve for fast charging and float charging is established based on the voltage data after noise reduction. The charging voltage of the backup power supply is evaluated in real time. When the evaluation result is greater than the preset threshold, it is diagnosed as an abnormal voltage curve.

[0135] In a preferred embodiment, during the charging phase, a standard charging time-theoretical voltage curve for fast charging and float charging is established based on the voltage data after noise reduction and processing. The charging voltage of the backup power supply is evaluated in real time. When the evaluation result exceeds a preset threshold, the voltage curve is diagnosed as abnormal. This includes: establishing a standard charging time-theoretical voltage curve for fast charging and float charging based on the characteristics of the backup power supply; identifying and removing outliers from the noise-reduced voltage data to obtain voltage data that conforms to the physical laws of charging; using the root mean square error method to evaluate the voltage data conforming to the physical laws of charging in real time based on the standard charging time-theoretical voltage curve for fast charging and float charging, obtaining an evaluation result; comparing the evaluation result with a preset threshold, and determining that the voltage curve is abnormal when the evaluation result exceeds the preset threshold.

[0136] It should be noted that the methods for judging fast charging timeout, control signal execution abnormality, backup power supply voltage over-limit abnormality, or voltage curve abnormality are as follows:

[0137] (1) Fast charging timeout abnormality; During the fast charging phase, when the fast charging time is greater than 6 hours (21600 seconds), it is diagnosed as "fast charging timeout abnormality".

[0138] (2) Abnormal control signal execution; when the control commands and feedback signals of controllable switches Km, K1, K2, K3, and K4 are inconsistent, it is diagnosed as "abnormal control signal execution".

[0139] (3) Backup power supply voltage exceeds limit abnormality; when the backup power supply voltage u backup Higher than the upper limit of the backup power supply voltage u backup_uplimt , where u backup_uplimt =u floatcharge +10. Diagnosed as "backup power supply voltage exceeding limits";

[0140] (4) Abnormal voltage curve; During the charging phase, establish standard charging time-theoretical voltage curves for fast charging and float charging, and evaluate the charging voltage in real time, specifically:

[0141] 1) Establish a standard charging time-theoretical voltage curve. This curve is based on the characteristics of the backup power supply and can be obtained through actual measurement. That is, charge the backup power supply under fault-free conditions and record the charging time and battery voltage. Figure 2 shows the charging time versus theoretical voltage u. Backup_nom curve.

[0142] Identify and eliminate abnormal values ​​in the actual measurement of backup power supply voltage. Abnormalities include statistical anomalies and physical constraints.

[0143] For statistical anomalies: Calculate the voltage standard deviation for each data set. For those that satisfy: ( This represents the local mean of the k-th group around time t. Points representing the k-th group at time t are marked as potential anomalies;

[0144] Physical constraints: Considering the three-stage characteristics of backup power charging (taking lead-acid batteries as an example):

[0145] During fast charging: the voltage should increase monotonically, and the rate of change should be... Δu represents the voltage change, which is the change in voltage over a period of time, and Δt represents the time change, which is the time interval during which the voltage change occurs.

[0146] Float charging phase: The voltage slowly decreases to the float charging voltage. (e.g., 13.5V).

[0147] Points that do not meet the stage characteristics, such as a voltage drop of 0.5V during the fast charging stage, are directly removed to ensure that the remaining data conforms to the physical laws of charging.

[0148] 2) Real-time evaluation of charging voltage; using root mean square error (RMSE) to quantify the degree of agreement between the theoretical and actual backup power voltage values, specifically:

[0149] ;

[0150] In the formula, M represents the number of sampling points. When RMSE > 0.5V, it is determined to be an "abnormal voltage curve".

[0151] In addition, the backup power system anomaly detection process is as follows: Figure 4 As shown, after the process starts, the system enters the rapid discharge phase. When the rapid discharge time reaches the rapid discharge cutoff time t... quickdischarge At that time, the system outputs the backup power supply voltage value u. dc1 It then enters the slow discharge phase, and when the slow discharge time reaches the slow discharge cutoff time t... slowdischarge At that time, the system outputs the backup power supply voltage value u. dc2 And stop discharging, calculate the voltage difference Δu between the backup power supply at the time the fast discharge ends and the slow discharge ends. dc :

[0152] ;

[0153] If △u dc Greater than the backup power supply diagnostic confidence value u dcset To determine if the power supply system is normal, if Δu dc Not greater than u dcset To determine if the power supply system is abnormal.

[0154] In a preferred embodiment, controlling the state of the controllable switch includes: under fast charging conditions, the controllable switch is controlled as follows: controllable switch Km closed, controllable switch K1 closed, controllable switch K2 open, and controllable switch K3 closed; under float charging conditions, the controllable switch is controlled as follows: controllable switch Km closed, controllable switch K1 closed, controllable switch K2 open, and controllable switch K3 open; under fast discharging conditions, the controllable switch is controlled as follows: controllable switch Km open, controllable switch K1 open, controllable switch K2 closed, and controllable switch K3 closed; under stopped charging conditions, the controllable switch is controlled as follows: controllable switch Km closed, controllable switch K1 open, controllable switch K2 open, and controllable switch K3 open.

[0155] According to another embodiment of the present invention, a backup power supply charging and diagnostic management method is provided. The method includes the following steps: rectifying AC power into DC power using a rectifier and supplying the DC power to a circuit control module; obtaining scheduling instructions through the circuit control module and changing the control switch combination based on the control instructions to limit the charging current and discharging current of the backup power supply; storing current in the backup power supply or outputting the stored current; obtaining control instructions, backup power supply status data, and circuit control module status data in real time using a controller, and combining preset charging trigger conditions to generate scheduling instructions from the circuit control module to perform abnormal diagnosis and charging control of the backup power supply.

[0156] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments.

[0157] Example: To test the feasibility of this invention, it was tested and applied on a 1.5MW wind turbine in a wind farm in Inner Mongolia. The backup power supply uses lead-acid batteries, and the backup power supply system parameters are shown in Table 2 below. The backup power supply system control parameters are shown in Table 3 below.

[0158] Table 2 Backup Power System Parameter Table

[0159] Table 3 System Control Parameter Table

[0160] The system was used for charging tests at an ambient temperature of 5℃. Curve 1 shows the system's critical state response curves during the float charging to charging stop phase, and curve 2 shows the system's critical state response curves during system anomaly detection. The data includes the system backup power supply voltage, and the state values ​​of controllable switches Km, K1, K2, and K3, with a period of 20ms.

[0161] like Figure 5 As shown in operating curve 1, before time 1021, the system is in the float charging stage. Controllable switches Km, K1, K2, and K3 are closed and open, respectively, causing the backup power supply voltage to rise continuously. When the backup power supply voltage reaches 411.5V, the system enters the stop charging phase, with controllable switches Km, K1, K2, and K3 closing and opening again. The backup power supply voltage is now 395V, completing the charging process. The operating state is consistent with the theoretical design.

[0162] like Figure 6As shown in the operating curve 2, before time 930, the system is in a stopped charging state, with controllable switch Km closed, controllable switch K1 open, controllable switch K2 open, and controllable switch K3 open, and the backup power supply voltage is 384V. When time is 903, the system enters a rapid discharge state, with controllable switch Km open, controllable switch K1 open, controllable switch K2 closed, and controllable switch K3 closed, and the backup power supply voltage begins to decrease. When time is 955, the backup power supply voltage is 359V, and the system enters a slow discharge state, with controllable switch Km open, controllable switch K1 open, controllable switch K2 closed, and controllable switch K3 open. When time is 980, the backup power supply voltage is 378V; the system enters a stopped charging state, with controllable switch Km closed, controllable switch K1 open, controllable switch K2 open, and controllable switch K3 open, and the backup power supply voltage is 380V.

[0163] Since the circuit is normal, with no short circuits or open circuits, the backup power supply effectively performs the fast and slow discharge processes. The difference between the backup power supply voltage of 359V after fast charging and 378V after slow charging is 19V, which is greater than the set value of 5V, indicating the system is normal and the anomaly diagnosis is complete. If the circuit is abnormal, such as with a short circuit or open circuit, this detection process will not cause a change in the backup power supply voltage; the difference between the backup power supply voltage after fast charging and slow charging will not exceed the set value of 5V.

[0164] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, optical storage, etc.) containing computer-usable program code.

[0165] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A backup power supply charging and diagnostic management system, characterized by, The application relates to a power supply system, which comprises a rectifier, a backup power supply, a circuit control module and a controller, wherein the rectifier, the circuit control module and the backup power supply are sequentially connected with the controller. The rectifier is used for rectifying alternating current into direct current and delivering the direct current to the circuit control module. The circuit control module is used for obtaining a scheduling instruction and changing a control switch combination based on the control instruction to limit the charging current and the discharging current of the backup power supply. The backup power supply is used for storing current or outputting the stored current. The controller is used for obtaining the control instruction, the state data of the backup power supply and the state data of the circuit control module in real time, combining a preset charging trigger condition, generating a scheduling instruction of the circuit control module, and performing abnormal diagnosis and charging control on the backup power supply. The real-time obtaining of the control instruction, the state data of the backup power supply and the state data of the circuit control module, the combination of the preset charging trigger condition, the generation of the scheduling instruction of the circuit control module and the abnormal diagnosis and charging control on the backup power supply comprise the following steps.

2. The backup power supply charging and diagnostic management system of claim 1, wherein, The real-time obtaining of the control instruction, the state data of the backup power supply and the state data of the circuit control module, the control instruction comprising a diagnosis instruction and a charging instruction, the state data of the backup power supply comprising voltage data and charging time, and the state data of the circuit control module being feedback signals of controllable switches Km, K1, K2, K3 and K4. When the control instruction is the diagnosis instruction, the voltage data of the backup power supply is denoised, the abnormal diagnosis is performed on the backup power supply based on the denoised voltage data and in combination with the charging time and the state data of the circuit control module. When the control instruction is the charging instruction, the voltage data of the backup power supply is denoised, whether the backup power supply satisfies the preset charging trigger condition is judged based on the denoised voltage data, and if yes, the control instruction of the circuit control module is generated to control the state of the controllable switch. The denoising of the voltage data of the backup power supply comprises the following steps.

3. The backup power supply charging and diagnostic management system of claim 2, wherein, The voltage time sequence signal of the voltage data of the backup power supply is converted, and the voltage time sequence signal is converted into a two-dimensional image matrix by using polar coordinate coding. The two-dimensional image matrix is encoded and decoded based on a preset lightweight U-Net network, and multi-scale feature maps are extracted. The multi-scale feature maps are denoised based on the characteristic that the pixel values of similar regions should be similar, and a denoised two-dimensional image is obtained. The denoised two-dimensional image is one-dimensional voltage time sequence inverse mapping processed, and denoised voltage data is obtained. The conversion of the voltage time sequence signal of the voltage data of the backup power supply into a two-dimensional image matrix by using polar coordinate coding comprises the following steps.

4. The backup power supply charging and diagnostic management system of claim 3, wherein, The voltage time sequence signal of the voltage data of the backup power supply is normalized, the voltage time sequence signal value is mapped to a preset angle interval and a radius interval, and a mapping result is obtained. Based on the mapping result, an image pixel value is constructed by using a Gramian angle field formula, and the time sequence correlation of any two time points is coded, and a two-dimensional image matrix is obtained. ​ 5. The backup power supply charging and diagnostic management system of claim 3, wherein, The one-dimensional voltage time sequence inverse mapping processing is performed on the two-dimensional image after noise reduction to obtain voltage data after noise reduction processing, comprising: According to the two-dimensional image after noise reduction, the main diagonal elements are extracted; According to the main diagonal elements, the two-dimensional image after noise reduction is mapped into a voltage time sequence by using the inverse formula to obtain the voltage data after noise reduction processing.

6. The backup power supply charging and diagnostic management system of claim 2, wherein, The abnormal diagnosis of the backup power supply includes fast charging timeout exception, control signal execution exception, backup power supply voltage overrun exception and voltage curve exception. The fast charging timeout exception is diagnosed as a fast charging timeout exception when the fast charging time is greater than the preset charging time in the fast charging stage. The control signal execution exception is diagnosed as a control signal execution exception when the feedback signals of the controllable switches Km, K1, K2, K3 and K4 are inconsistent with the control commands. The backup power supply voltage overrun exception is diagnosed as a backup power supply voltage overrun exception when the voltage data after noise reduction processing is higher than the upper limit of the backup power supply voltage. The voltage curve exception is diagnosed as a voltage curve exception when the evaluation result is greater than the preset threshold value based on the voltage data after noise reduction processing in the charging stage.

7. The backup power supply charging and diagnostic management system of claim 6, wherein, The voltage curve exception is diagnosed as a voltage curve exception when the evaluation result is greater than the preset threshold value based on the voltage data after noise reduction processing in the charging stage. In the charging stage, the standard charging time-theoretical voltage curve of fast charging and floating charging is established based on the voltage data after noise reduction processing, and the charging voltage of the backup power supply is evaluated in real time. The voltage curve exception is diagnosed as a voltage curve exception when the evaluation result is greater than the preset threshold value based on the voltage data after noise reduction processing in the charging stage. In the charging stage, the standard charging time-theoretical voltage curve of fast charging and floating charging is established based on the backup power supply characteristics; The voltage data after noise reduction processing is subjected to outlier identification and elimination to obtain voltage data conforming to the charging physical law; 8. The backup power supply charging and diagnostic management system of claim 1, wherein, Based on the standard charging time-theoretical voltage curve of fast charging and floating charging, the voltage data conforming to the charging physical law is evaluated in real time by using the root mean square error method to obtain the evaluation result. The evaluation result is compared with the preset threshold value, and the evaluation result is greater than the preset threshold value, which is determined as a voltage curve exception. ； The limit of the charging current and discharging current of the backup power supply includes fast charging current, floating current, fast discharging current, slow discharging current and stop charging current. ； The expression of the fast charging current is: ； The expression of the floating current is: ； The expression of the fast discharging current is: ； where i 快充 represents a fast charging current, i 慢充 represents a float charging current, i 快放 represents a fast discharging current, i 慢放 represents a slow discharging current, i 停止 represents a stop charging current, u DC represents a rectifier output voltage, u backup represents a backup power terminal voltage, R in represents a backup power internal resistance, R1 represents a resistance value of the resistance R1, R2 represents a resistance value of the resistance R2, and R3 represents a resistance value of the resistance R3.

9. The backup power supply charging and diagnostic management system of claim 1, wherein, The expression of the slow discharging current is: The expression of the stop charging current is: The circuit control module includes resistors R1, R2, R3, controllable switches K1, K2, K3 and K4. One end of the controllable switch K1 is connected with the rectifier, the other end of the controllable switch K1 is connected with one end of the resistor R1 in series and connected with the controllable switch K2 and the resistor R2 in parallel; the other end of the resistor R1 is connected with one end of the resistor R3 in series, the other end of the resistor R3 is connected with one end of the controllable switch K4, the controllable switch K3 is connected in parallel across the resistor R3, the other ends of the controllable switch K4 are connected with the positive and negative poles of the backup power supply respectively; the controllable switch K2 and the resistor R2 are connected in parallel across the resistor R1 in parallel.

10. The backup power supply charging and diagnostic management system of claim 1, wherein, One end of the rectifier is connected with three-phase alternating current of commercial power through the controllable switch Km.

11. The backup power supply charging and diagnostic management system of claim 2, wherein, The control of the controllable switch state comprises: In the fast charging condition, the control mode of the controllable switch is that the controllable switch Km is closed, the controllable switch K1 is closed, the controllable switch K2 is disconnected, and the controllable switch K3 is closed; In the float charging condition, the control mode of the controllable switch is that the controllable switch Km is closed, the controllable switch K1 is closed, the controllable switch K2 is disconnected, and the controllable switch K3 is disconnected; In the fast discharging condition, the control mode of the controllable switch is that the controllable switch Km is disconnected, the controllable switch K1 is disconnected, the controllable switch K2 is closed, and the controllable switch K3 is closed; In the slow discharging condition, the control mode of the controllable switch is that the controllable switch Km is disconnected, the controllable switch K1 is disconnected, the controllable switch K2 is closed, and the controllable switch K3 is disconnected; In the stop charging condition, the control mode of the controllable switch is that the controllable switch Km is closed, the controllable switch K1 is disconnected, the controllable switch K2 is disconnected, and the controllable switch K3 is disconnected.

12. A backup power supply charging and diagnostic management method of operating the backup power supply charging and diagnostic management system according to any one of claims 1 to 11, characterized by, The method comprises the following steps: The alternating current is rectified into direct current by the rectifier, and the direct current is delivered to the circuit control module; The dispatching instruction is obtained by the circuit control module, and the control switch combination is changed based on the control instruction to limit the charging current and discharging current of the backup power supply; The current is stored by the backup power supply or the stored current is outputted; The controller obtains the control instruction, the state data of the backup power supply and the state data of the circuit control module in real time, and combines the preset charging trigger condition to generate the dispatching instruction of the circuit control module to diagnose and control the backup power supply abnormally.

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