Output control method of inverter, inverter, energy storage power supply and storage medium
By superimposing a load detection signal onto the inverter's modulation signal, the control parameters are identified and adjusted, solving the robustness and dynamic response problems of traditional inverters when facing complex loads, improving output stability and power quality, and reducing commissioning costs.
Patent Information
- Application Number
- CN202610198272.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-02-10
- Publication Date
- 2026-05-29
Smart Images
Figure CN122118816A_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the field of inverter control technology for energy storage power supplies, and particularly relates to an output control method for an inverter, an inverter, an energy storage power supply, and a computer-readable storage medium. Background Technology
[0002] The loads of inverters are highly diverse and uncertain: they may be purely resistive, inductive, capacitive, or nonlinear loads. The impedance values of different loads vary greatly, and the load may suddenly increase, decrease, or be completely disconnected during operation, which will affect the output stability.
[0003] Traditional inverter control strategies, especially PI (Proportional Gain-Integral Gain) controllers, typically have fixed parameters. This approach makes the inverter's output performance highly susceptible to fluctuations when faced with complex and variable real-world loads. Summary of the Invention
[0004] This application aims to address at least one of the technical problems existing in the prior art. To this end, this application proposes an inverter output control method, an inverter, an energy storage power supply, and a computer-readable storage medium, which can quickly detect the changed load parameters based on load changes and adaptively adjust the inverter control parameters, thereby ensuring the output performance of the inverter.
[0005] In a first aspect, this application provides an output control method for an inverter, the inverter being used to supply power to a connected load, the method comprising: When the load connected to the inverter changes, a load detection signal is superimposed on the modulation signal of the inverter, and the load detection signal can be distinguished from the modulation signal; The output electrical parameters of the inverter are collected to generate an output signal; Identify the fundamental frequency and load response signal in the output signal, wherein the fundamental frequency corresponds to the modulation signal and the load response signal corresponds to the load detection signal; Based on the load response signal, determine the changed load parameters; Adjust the control parameters of the inverter so that the output electrical parameters of the inverter match the changed load parameters.
[0006] Secondly, this application provides an inverter that includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, it implements the output control method of the inverter described above.
[0007] Thirdly, this application provides an energy storage power source, including a battery and an inverter, wherein the inverter is electrically connected to the battery.
[0008] Fourthly, this application provides a non-transitory computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the above-described inverter output control method.
[0009] The inverter output control method, inverter, energy storage power supply, and computer-readable storage medium provided in this application embodiment trigger impedance detection when the load connected to the inverter changes, thereby superimposing a load detection signal onto the modulation signal of the inverter. In order to facilitate subsequent differentiation of the load response signal corresponding to the superimposed load detection signal, the superimposed load detection signal is different from the modulation signal.
[0010] Then, the output electrical parameters of the inverter after the load detection signal is superimposed are collected to generate the output signal. Due to the change in load, the change in load impedance will cause the output electrical parameters of the inverter to change. Thus, by separating the fundamental wave in the output signal, the load response signal corresponding to the load detection signal (i.e. the voltage and current changes caused by the load change) can be identified in the output signal.
[0011] Finally, based on the load response signal generated by the voltage and current changes caused by load variations, the changed load parameters, such as the load impedance magnitude and type, can be identified. Based on these changed load parameters, the inverter's control parameters are adaptively adjusted to match the inverter's output electrical parameters with the changed load parameters, thus ensuring the inverter's output performance.
[0012] Additional aspects and advantages of embodiments of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of embodiments of this application. Attached Figure Description
[0013] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram illustrating an application scenario of the control method provided in some embodiments of this application; Figure 2 This is a first flowchart illustrating the control method provided in certain embodiments of this application; Figure 3 This is a second flowchart illustrating the control method provided in certain embodiments of this application; Figure 4 This is a third flowchart illustrating the control method provided in certain embodiments of this application; Figure 5 This is a fourth flowchart illustrating the control method provided in certain embodiments of this application; Figure 6This is a schematic diagram of a control device provided in some embodiments of this application. Detailed Implementation
[0014] The embodiments of this application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.
[0015] The technical background of this application will be introduced below: The loads of inverters are highly diverse and uncertain: they may be purely resistive, inductive, capacitive, or nonlinear loads. The impedance values of different loads vary greatly, and the load may suddenly increase, decrease, or be completely disconnected during operation, which will affect the output stability.
[0016] Traditional inverter control strategies, especially PI controllers, typically use fixed control parameters or are tuned offline for a single typical load. This approach suffers from poor robustness, slow dynamic response, low power quality, and high commissioning costs when facing complex and variable real-world loads. Furthermore, PI parameters optimized for a specific load can experience a sharp performance drop when subjected to light or heavy loads, or when the load type changes. When the load changes abruptly, controllers with fixed parameters cannot adapt quickly, potentially leading to significant overshoot, oscillations, or even instability in the output voltage and current. Under non-rated loads, fixed parameters cannot guarantee that the total distortion (THD) of the output voltage meets requirements, which may damage sensitive equipment. For different application scenarios and loads, engineers need to perform extensive on-site commissioning to determine suitable PI parameters, which is time-consuming and labor-intensive.
[0017] This application proposes an inverter output control method. When the load connected to the inverter changes, impedance detection is triggered, and a load detection signal is superimposed on the inverter's modulation signal. Based on the load response signal generated by the voltage and current changes caused by the load change, the changed load parameters can be identified, and the inverter's control parameters can be adjusted adaptively. This ensures that the inverter's output electrical parameters match the changed load parameters, guaranteeing the inverter's output performance and solving the shortcomings of poor robustness, slow dynamic response, low output power quality, and high debugging costs of inverter output after load changes.
[0018] Please see Figure 1 , Figure 1 This is an application scenario diagram of an inverter output control method provided in an embodiment of this application. The application scenario provided in this application includes an energy storage power supply 100 and an electronic device 200.
[0019] Among them, the energy storage power supply stores a large amount of power, and when needed, the energy stored in the battery is output for use. Energy storage power supply 200 refers to a device capable of storing power. It is generally equipped with a rechargeable battery, and the energy is stored within the battery of the energy storage power supply. There are many types of energy storage power supplies, which can be classified according to application scenarios: (1) Portable energy storage: It is generally a small energy storage power supply, using lithium-ion batteries, etc. It is easy to carry and used for outdoor camping, emergency charging and other scenarios. It can power mobile phones, computers, lighting equipment, etc.
[0020] (2) Home energy storage: Used in homes to store solar power or electricity generated during off-peak hours of the power grid for use by home electrical equipment, achieving the purpose of peak shaving and valley filling, saving electricity costs, etc.
[0021] (3) Industrial and commercial energy storage: Used in factories, data centers, shopping malls and other places, it can be used for load regulation, demand-side management, power quality improvement, etc., to help users reduce electricity costs and improve power supply reliability.
[0022] (4) Grid energy storage: It is widely used in power systems to regulate the peak-valley difference of the power grid, smooth the fluctuations of renewable energy generation, and improve the stability and reliability of the power grid. Common types include large lithium-ion battery energy storage power stations, flow battery energy storage power stations, and pumped storage power stations.
[0023] In order to adapt to the increasingly diverse power consumption scenarios, portable energy storage power supplies have emerged. Portable energy storage power supplies, also known as portable lithium-ion battery energy storage power supplies or outdoor power supplies, usually refer to backup or emergency power supplies weighing no more than 18 kg. They use lithium-ion batteries as energy storage components and have AC or DC input charging interfaces as well as AC or DC output interfaces.
[0024] In one alternative embodiment, the energy storage power supply 100 includes a battery 101, a main control board 102, a battery management system 103, an inverter 104, and a real-time clock module 105.
[0025] Among them, the battery is the energy core of the energy storage power supply and is the component that stores the power.
[0026] The main control board is the core of the energy storage power supply. The system's wake-up, shutdown, charging judgment, and power consumption management are all controlled by the main control board.
[0027] Among them, the Battery Management System (BMS) is an electronic system used to monitor, protect, optimize and manage batteries (such as lithium batteries, lead-acid batteries, etc.). Its core function is to ensure that the battery works efficiently within a safe range, extend its service life, and provide stable power output to the equipment.
[0028] For example, a battery management system can control the charging and discharging switches to achieve charging and discharging control; and it can achieve battery balancing by detecting the electrical parameters of each cell in the battery.
[0029] An inverter is a power electronic device that converts direct current (DC) to alternating current (AC). The inverter itself may be equipped with a PI controller, which includes a processor and a memory. The processor is used to execute the inverter output control method of this application.
[0030] Among them, the Real-Time Clock Module (RTC module) is an electronic module specifically designed to accurately record and maintain time information. It can continue to operate when the device is powered off or in a low-power state, providing a stable and accurate time reference for various electronic systems.
[0031] In one alternative embodiment, the energy storage power supply 100 is able to communicate with the electronic device 200 to cooperate with the electronic device 200 in implementing the inverter output control method of this application.
[0032] Optionally, the electronic device 200 includes at least one of a terminal and a server.
[0033] The terminal may include, but is not limited to: smartphones (such as Android phones, iOS phones, etc.), tablet computers, laptops, desktop computers, smart speakers, smartwatches, portable personal computers, mobile internet devices (MIDs), smart voice interaction devices, smart home appliances, vehicle terminals, aircraft, wearable devices, etc., but this application embodiment does not limit the scope of the terminal.
[0034] The server can be a standalone physical server, a server cluster or distributed system composed of multiple physical servers, or a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communication, middleware services, domain name services, security services, CDN (Content Delivery Network), and big data and artificial intelligence platforms. This application does not limit this.
[0035] The output control method of the inverter in this application can be implemented by the inverter alone, or the inverter can be implemented in conjunction with energy storage power supply and / or electronic equipment, without limitation.
[0036] It is understood that in the specific implementation of this application, user object data, context data and other related data are involved. When the embodiments of this application are applied to specific products or technologies, user permission or consent is required, and the collection, use and processing of related data must comply with the relevant laws, regulations and standards of the relevant countries and regions.
[0037] Based on the above technical background and application scenarios, this application provides an inverter output control method, which is described in detail below: Please see Figure 2 This application provides an inverter output control method, which is implemented by steps 011 to 015, and is described in detail below.
[0038] Step 011: When the load connected to the inverter changes, a load detection signal is superimposed on the modulation signal of the inverter. The load detection signal can be distinguished from the modulation signal.
[0039] The inverter can be connected to one or more loads. Users can adjust the loads connected to the inverter according to their needs, such as increasing or decreasing the number of loads, or replacing different loads.
[0040] In one optional embodiment, in response to receiving a first trigger command generated by a timer, the inverter's output current change rate being greater than a preset change rate threshold, or receiving a second trigger command, it is determined that the load connected to the inverter has changed.
[0041] It's understandable that the load will typically change at preset intervals depending on the power supply scenario. Therefore, the inverter's load impedance detection process can be triggered periodically, such as by setting a timer that triggers at preset intervals, generating a first trigger command. Upon receiving the first trigger command, the inverter can determine that the load connected to it has changed.
[0042] Alternatively, after the load connected to the inverter changes, the output current of the inverter will generally change. Therefore, by detecting whether the rate of change of the output current is greater than a preset rate of change threshold, it can be determined whether the load connected to the inverter has changed.
[0043] Alternatively, after manually changing the load, the user can also trigger the load impedance detection process. The user can issue a second trigger command through the host computer or an electronic device that communicates with the energy storage power supply to determine that the load connected to the inverter has changed.
[0044] Among them, the modulation signal of the inverter is the core control signal that drives the inverter power bridge (IGBT / MOSFET) to complete the DC-AC power conversion. In essence, it generates a PWM drive signal by comparing an electrical signal with a fixed frequency carrier wave (such as a triangular wave) through the amplitude / frequency / phase change of the electrical signal, and finally controls the on and off timing of the power transistors so that the inverter outputs an AC voltage that meets the requirements (such as a 50 / 60Hz sine wave at the power frequency).
[0045] The load detection signal is a low-amplitude, narrow-bandwidth sinusoidal signal, to distinguish it from a modulation signal. This is to avoid the load detection signal affecting the inverter output while implementing load detection.
[0046] For example, the amplitude of the load detection signal is smaller than the amplitude of the modulation signal, and the bandwidth of the load detection signal is smaller than the bandwidth of the modulation signal.
[0047] Specifically, in order to detect the changed load parameters when the inverter load changes, a load detection signal can be superimposed on the inverter's modulation signal.
[0048] For example, the inverter's modulation signal (such as PWM duty cycle, modulation amplitude / phase) is superimposed and modulated by the load detection signal, and then the load detection signal is coupled to the final AC output terminal through the inverter's power conversion stage.
[0049] Step 012: Collect the output electrical parameters of the inverter to generate an output signal.
[0050] After the load detection signal is superimposed on the modulation signal of the inverter, the output electrical parameters of the inverter change accordingly with the changes in the superimposed signal and the load.
[0051] Changes in load will cause changes in the inverter's output electrical parameters. Therefore, by collecting the inverter's output electrical parameters, an output signal can be generated.
[0052] Step 013: Identify the fundamental frequency and load response signal in the output signal. The fundamental frequency corresponds to the modulation signal, and the load response signal corresponds to the load detection signal.
[0053] It is understandable that the output signal includes the load response signal corresponding to the load detection signal. Changes in the load will cause changes in the load response signal, and there is a regular correlation between the changed load response signal and the changed load. For example, when the load impedance increases, the effective value of the current in the load response signal will decrease accordingly.
[0054] Therefore, by separating the fundamental wave and the load response signal in the output signal, the load response signal after the load change is obtained. The fundamental wave corresponds to the modulation signal, and the load response signal corresponds to the load detection signal.
[0055] Please see Figure 3 In an optional embodiment, the output electrical parameters include output voltage and output current, and the output signal includes output current signal and output voltage signal. Step 013, identifying the fundamental frequency and load response signal in the output signal, includes: Step 0131: Filter the output current signal and the output voltage signal to generate a voltage filter signal and a current filter signal, respectively. The filtering process includes at least one of smoothing filtering and Fourier transform. Step 0132: Decompose the first fundamental frequency and the voltage load response signal in the voltage filter signal; Step 0133: Decompose the second fundamental wave and the current load response signal in the current filter signal.
[0056] It is understandable that the impedance in the load parameters is generally related to both voltage and current. The output voltage signal is generated by collecting the output voltage, and the output current signal is generated by collecting the output current.
[0057] To improve the accuracy of load response signal identification, the output current signal and output voltage signal can be filtered first to generate voltage filtered signal and current filtered signal respectively.
[0058] In one alternative embodiment, the filtering process includes at least one of smoothing filtering and Fourier transform.
[0059] In inverter scenarios, smoothing filtering and Fast Fourier Transform (FFT) are used. The former is responsible for removing signal noise and smoothing the waveform, while the latter is responsible for converting the time-domain signal into the frequency domain and analyzing the frequency components of the signal (such as harmonics, small signals, and power frequency components).
[0060] Thus, noise in the output current and output voltage signals can be removed through filtering, improving the accuracy of the voltage and current filtered signals.
[0061] Then, the first fundamental wave and voltage load response signal in the voltage filter signal are decomposed; the second fundamental wave and current load response signal in the current filter signal are decomposed.
[0062] After obtaining the voltage load response signal and the current load response signal, subsequent load parameter calculations can be performed.
[0063] Step 014: Determine the changed load parameters based on the load response signal.
[0064] After obtaining the load response signal, the changed load parameters can be determined based on the load response signal associated with the load change.
[0065] In an optional embodiment, the load parameters include impedance magnitude and load type. Step 014, based on the load response signal, determines the changed load parameters, including: Step 0141: Determine the impedance amplitude based on the ratio of the effective voltage value corresponding to the voltage load response signal to the effective current value corresponding to the current load response signal; Step 0142: Determine the load type based on the phase difference between the voltage load response signal and the current load response signal.
[0066] For example, the effective voltage value corresponding to the voltage load response signal and the effective current value corresponding to the current load response signal can be calculated, and then the impedance amplitude can be determined based on the ratio of the effective voltage value to the effective current value.
[0067] The phase changes of voltage load response signals and current load response signals are different for different load types. Therefore, the load type can be determined based on the phase difference between the voltage load response signals and the current load response signals.
[0068] In one optional embodiment, the load type includes a purely resistive load, an inductive load, and a capacitive load. When the phase difference is 0, the load type is determined to be a purely resistive load; when the phase difference is greater than 0, the load type is determined to be an inductive load; and when the phase difference is less than 0, the load type is determined to be a capacitive load.
[0069] Thus, the load type can be quickly determined by the phase difference.
[0070] Step 015: Adjust the inverter's control parameters so that the inverter's output electrical parameters match the changed load parameters.
[0071] The control parameters may include those of the inverter's proportional-integral controller. Thus, by adjusting the inverter's proportional and integral coefficients, the inverter's output can be quickly adjusted.
[0072] By adjusting the inverter's control parameters, the inverter's output electrical parameters are adjusted to match the changed load parameters, thereby ensuring the inverter's output performance.
[0073] In an optional embodiment, step 015, adjusting the inverter's control parameters to match the inverter's output electrical parameters with the changed load parameters, includes: Step 0151: Determine the target control parameters based on the load parameters and the preset mapping table; Step 0152: Adjust the inverter's control parameters to the target control parameters.
[0074] The preset mapping table includes the mapping relationship between load parameters and control parameters, which can be obtained through pre-calibration. By controlling the inverter operation with control parameters that match the load parameters, it can be ensured that the inverter's output electrical parameters match the changed load parameters, thereby ensuring the inverter's output performance.
[0075] For example, ensuring inverter output performance can be achieved by ensuring inverter output stability, so that the inverter's output electrical parameters remain stable and close to the desired target electrical parameters. This can be done by calculating the variance between each output electrical parameter and the target electrical parameter, and using the variance to measure the inverter's output performance. Another example is ensuring inverter output performance by making the inverter's dynamic response time (i.e., from the start of a load change to the end of the inverter's output matching the changed load) less than a preset response time.
[0076] By querying the mapping table using the changed load parameters, the target control parameters corresponding to the changed load parameters can be quickly obtained. This allows the inverter's current control parameters to be changed to the target control parameters, and the inverter outputs the inverter based on the target control parameters.
[0077] In one alternative embodiment, if the inverter's output electrical parameters do not match the changed load parameters when the inverter's control parameters are adjusted to the target control parameters, the load parameters are recalculated, and the inverter's control parameters are adjusted again to match the recalculated load parameters.
[0078] It is understandable that, with the inverter's control parameters adjusted to the target control parameters, the inverter's output performance, such as output stability (e.g., whether the output electrical parameters consistently approach or equal the target electrical parameters), can be evaluated based on the inverter's output electrical parameters. If the inverter's output performance meets the requirements, it can be determined that the inverter's output electrical parameters match the changed load parameters. Conversely, if the inverter's output performance does not meet the requirements, it can be determined that the inverter's output electrical parameters do not match the changed load parameters. In this case, the load parameters need to be recalculated, and the inverter's control parameters need to be adjusted again to match the inverter's output electrical parameters with the recalculated load parameters. This process is repeated until the inverter's output electrical parameters match the recalculated load parameters, thus ensuring the inverter's output performance.
[0079] It is understandable that when recalculating load parameters, new load detection signals (with different amplitudes and bandwidths) can be superimposed to avoid the problem of low accuracy of load parameters corresponding to some load detection signals.
[0080] The inverter output control method provided in the embodiments of this application triggers impedance detection when the load connected to the inverter changes, thereby superimposing a load detection signal on the modulation signal of the inverter. In order to facilitate the subsequent differentiation of the load response signal corresponding to the superimposed load detection signal, the superimposed load detection signal is different from the modulation signal.
[0081] Then, the output electrical parameters of the inverter after the load detection signal is superimposed are collected to generate the output signal. Due to the change in load, the change in load impedance will cause the output electrical parameters of the inverter to change. Thus, by separating the fundamental wave in the output signal, the load response signal corresponding to the load detection signal (i.e. the voltage and current changes caused by the load change) can be identified in the output signal.
[0082] Finally, based on the load response signal generated by the voltage and current changes caused by load variations, the changed load parameters, such as the load impedance magnitude and type, can be identified. Based on these changed load parameters, the inverter's control parameters are adaptively adjusted to match the inverter's output electrical parameters with the changed load parameters, thus ensuring the inverter's output performance.
[0083] Please see Figure 4 In an optional embodiment, the changed load parameters include multiple parameters. Step 011 involves superimposing a load detection signal onto the inverter's modulation signal, including: Step 0111: Based on the variance of multiple changed load parameters, determine whether the load connected to the inverter includes nonlinear loads. Step 0112: When the load connected to the inverter includes a nonlinear load, load detection signals of different frequencies are sequentially superimposed on the modulation signal of the inverter. Step 014: Based on the load response signal, determine the changed load parameters, including: Step 0143: Based on the load response signals corresponding to the superimposed load detection signals, determine each load parameter respectively; Step 0144: Determine the changed load parameters based on the average or median of each load parameter.
[0084] It's understandable that loads can include linear and nonlinear loads. The impedance of a linear load remains essentially constant, while that of a nonlinear load changes with variations in operating electrical parameters. For linear loads, calculating the impedance amplitude once is sufficient to ensure accuracy. However, for nonlinear loads, multiple impedance amplitude calculations are required, and the average or median value is taken to maximize the accuracy of the impedance amplitude calculation.
[0085] Therefore, during the superposition of each impedance detection signal, multiple load parameters can be detected. The load type of these parameters is largely unaffected by whether the load is linear, while the impedance amplitude is affected by whether the load is linear. Thus, based on the variance of multiple changed impedance amplitudes, it can be determined whether the load connected to the inverter includes a nonlinear load. If the variance is greater than or equal to a preset variance, the load connected to the inverter is determined to be a nonlinear load; if the variance is less than the preset variance, the load connected to the inverter is determined to be a linear load.
[0086] When the load connected to the inverter includes a nonlinear load, load detection signals of different frequencies can be sequentially superimposed on the inverter's modulation signal. For example, the load detection signals of different frequencies may include a first load detection signal, a second load detection signal, and a third load detection signal.
[0087] Based on the load response signals corresponding to the superimposed load detection signals, each load parameter is determined. For example, by first superimposing the first load detection signal onto the modulation signal, the first impedance amplitude can be obtained; by superimposing the second load detection signal onto the modulation signal, the second impedance amplitude can be obtained; and by superimposing the third load detection signal onto the modulation signal, the third impedance amplitude can be obtained.
[0088] Finally, the changed load parameters are determined based on the average or median of each load parameter. For example, the impedance magnitude in the changed load parameters is determined based on the average or median of the first, second, and third impedance magnitudes.
[0089] Please see Figure 5 In some embodiments, the inverter output control method further includes: Step 016: Based on the inverter's output current, adjust the amplitude of the load detection signal so that the first amplitude of the load detection signal under the first load is less than the first amplitude under the second load, and the impedance of the first load is less than the impedance of the second load.
[0090] It is understandable that the impedance of the load may change. If the same load detection signal is superimposed on loads with different impedances, it may lead to problems such as low sampling signal-to-noise ratio under weak load and interference of the load detection signal with the inverter output under strong load.
[0091] Therefore, the approximate amplitude of the load can be evaluated based on the inverter's output current. This allows for adaptive adjustment of the load detection signal amplitude under different load conditions, ensuring that the adjusted amplitude does not affect the sampling signal-to-noise ratio or interfere with the inverter's output. This solves the problems of low sampling signal-to-noise ratio under weak loads and interference from the load detection signal with the inverter's output under strong loads, further improving the accuracy of load parameter detection.
[0092] In some embodiments, after the load detection signal superposition stops, the inverter's modulation signal can be processed by a first-order low-pass filter. This ensures a smooth transition of the inverter's modulation signal, avoids abrupt changes in the inverter's output, and guarantees the inverter's output performance.
[0093] In some embodiments, if the impedance amplitude is outside the preset impedance range, it is determined that the load parameter calculation is abnormal. A new load detection signal (such as a load detection signal with different amplitude and bandwidth) is then superimposed, and the load parameters are re-detected to improve the robustness of load parameter detection.
[0094] This application embodiment also provides a control device 300 for executing the steps in the above-described output control method for an inverter. See also... Figure 6 , Figure 6 This is a schematic diagram of a control device 300 provided in an embodiment of this application. The control device 300 includes: The superposition module 301 is used to superimpose a load detection signal onto the modulation signal of the inverter when the load connected to the inverter changes. The load detection signal can be distinguished from the modulation signal. The acquisition module 302 is used to acquire the output electrical parameters of the inverter in order to generate an output signal; The identification module 303 is used to identify the fundamental wave and the load response signal in the output signal. The fundamental wave corresponds to the modulation signal, and the load response signal corresponds to the load detection signal. The determination module 304 is used to determine the changed load parameters based on the load response signal; Adjustment module 305 adjusts the control parameters of the inverter so that the output electrical parameters of the inverter match the changed load parameters.
[0095] It should be noted that the specific details of each module unit in the control device 300 have been described in detail in the embodiments of the control method, and will not be repeated here.
[0096] In the embodiments of this application, the terms "module" or "unit" refer to a computer program or part of a computer program that has a predetermined function and works with other related parts to achieve a predetermined goal, and can be implemented wholly or partially using software, hardware (such as processing circuitry or memory), or a combination thereof. Similarly, a processor (or multiple processors or memory) can be used to implement one or more modules or units. Furthermore, each module or unit can be part of an overall module or unit that includes the functionality of that module or unit.
[0097] In some embodiments, the control device in this application can be implemented in hardware, such as an energy storage power supply or a component in the energy storage power supply, such as an integrated circuit or a chip; the control device can also be implemented in software, such as as a terminal or an application installed in the energy storage power supply.
[0098] In some embodiments, the energy storage power supply includes a main control board, a charging interface, and a battery. The main control board includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, it implements the various processes of the above-described embodiments of the output control method for the inverter and achieves the same technical effect. To avoid repetition, these will not be described again here.
[0099] In some embodiments, the electronic device includes a processor and a memory. The memory stores a computer program that can run on the processor. When executed by the processor, the program implements the various processes of the embodiments of the output control method for the inverter described above, and achieves the same technical effects. To avoid repetition, it will not be described again here.
[0100] This application also provides a non-transitory computer-readable storage medium storing a computer program. When the computer program is executed by a processor, it implements the various processes of the above-described inverter output control method embodiments and achieves the same technical effect. To avoid repetition, it will not be described again here.
[0101] The processor can be the processor in the energy storage power supply of the above embodiments. The computer-readable storage medium can be a computer read-only memory (ROM), random access memory (RAM), magnetic disk, or optical disk, etc.
[0102] Computer-readable media can include computer storage media and communication media. Computer storage media includes volatile and non-volatile, removable and non-removable media implemented using any method or technology for storing information such as computer-readable instructions, data structures, program modules, or other data. Computer storage media include RAM, ROM, erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other solid-state storage technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape cassettes, magnetic tape, disk storage, or other magnetic storage devices. Of course, those skilled in the art will recognize that computer storage media are not limited to the above-mentioned types.
[0103] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the above-described inverter output control method. The processor may be the processor in the energy storage power supply described in the above embodiments. When executed by the processor, this computer program implements various processes of the embodiments of the above-described inverter output control method and achieves the same technical effects; therefore, to avoid repetition, it will not be described again here.
[0104] It is understood that in the specific implementation of this application, data related to user identity or characteristics is involved. When the above embodiments of this application are applied to specific products or technologies, user permission or consent is required, and the collection, use and processing of related data must comply with the relevant laws, regulations and standards of the relevant countries and regions.
[0105] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.
Claims
1. An output control method for an inverter, characterized in that, The inverter is used to supply power to the connected load, and the method includes: When the load connected to the inverter changes, a load detection signal is superimposed on the modulation signal of the inverter, and the load detection signal can be distinguished from the modulation signal; The output electrical parameters of the inverter are collected to generate an output signal; Identify the fundamental frequency and load response signal in the output signal, wherein the fundamental frequency corresponds to the modulation signal and the load response signal corresponds to the load detection signal; Based on the load response signal, determine the changed load parameters; Adjust the control parameters of the inverter so that the output electrical parameters of the inverter match the changed load parameters.
2. The inverter output control method according to claim 1, characterized in that, Also includes: In response to receiving a first trigger command generated by a timer, the inverter's output current change rate being greater than a preset change rate threshold, or receiving a second trigger command, it is determined that the load connected to the inverter has changed.
3. The inverter output control method according to claim 1, characterized in that, The amplitude of the load detection signal is smaller than the amplitude of the modulation signal, and the bandwidth of the load detection signal is smaller than the bandwidth of the modulation signal.
4. The inverter output control method according to claim 1 or 3, characterized in that, Also includes: Based on the output current of the inverter, the amplitude of the load detection signal is adjusted so that the first amplitude of the load detection signal under the first load is less than the first amplitude under the second load, and the impedance of the first load is less than the impedance of the second load.
5. The inverter output control method according to claim 1, characterized in that, The output electrical parameters include output voltage and output current, the output signal includes output current signal and output voltage signal, and the identification of the fundamental frequency and load response signal in the output signal includes: The output current signal and the output voltage signal are filtered to generate a voltage filtered signal and a current filtered signal, respectively. The filtering process includes at least one of smoothing filtering and Fourier transform. Decompose the first fundamental frequency and the voltage load response signal in the voltage filtered signal; Decompose the second fundamental frequency and the current load response signal in the current filtered signal.
6. The inverter output control method according to claim 5, characterized in that, The load parameters include impedance amplitude and load type. Determining the changed load parameters based on the load response signal includes: The impedance amplitude is determined based on the ratio of the effective voltage value corresponding to the voltage load response signal to the effective current value corresponding to the current load response signal. The load type is determined based on the phase difference between the voltage load response signal and the current load response signal.
7. The inverter output control method according to claim 6, characterized in that, The load types include purely resistive loads, inductive loads, and capacitive loads. Determining the load type based on the phase difference between the voltage load response signal and the current load response signal includes: When the phase difference is 0, the load type is determined to be the purely resistive load; If the phase difference is greater than 0, the load type is determined to be the inductive load; If the phase difference is less than 0, the load type is determined to be the capacitive load.
8. The output control method for an inverter according to any one of claims 5-7, characterized in that, The control parameters include the control parameters of the inverter's proportional-integral controller. Adjusting the inverter's control parameters to match the inverter's output electrical parameters with the changed load parameters includes: Based on the load parameters and the preset mapping table, the target control parameters are determined; Adjust the control parameters of the inverter to the target control parameters.
9. The inverter output control method according to claim 8, characterized in that, Adjusting the control parameters of the inverter to match the output electrical parameters of the inverter with the changed load parameters includes: If the inverter's output electrical parameters do not match the changed load parameters when the inverter's control parameters are adjusted to the target control parameters, the load parameters are recalculated, and the inverter's control parameters are adjusted again to match the recalculated load parameters.
10. The inverter output control method according to claim 1, characterized in that, The changed load parameters include multiple parameters, and the superposition of the load detection signal into the modulation signal of the inverter includes: Based on the variance of the multiple changed load parameters, determine whether the load connected to the inverter includes a nonlinear load; When the load connected to the inverter includes a nonlinear load, load detection signals of different frequencies are sequentially superimposed on the modulation signal of the inverter. The step of determining the changed load parameters based on the load response signal includes: Based on the load response signals corresponding to the superimposed load detection signals, each load parameter is determined. The changed load parameters are determined based on the average or median of each load parameter.
11. An inverter, characterized in that, It includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the program, implements the method as described in any one of claims 1-10.
12. An energy storage power source, characterized in that, It includes a battery and an inverter as described in claim 11, wherein the inverter is electrically connected to the battery.
13. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the method as described in any one of claims 1-10.