Uninterruptible power supply, control method of uninterruptible power supply, related equipment and system

Abstract

The embodiment of the invention provides an uninterruptible power supply, a control method of the uninterruptible power supply, related equipment and a system, and relates to the technical field of electric power. Comprising a bypass switch and a DC / AC inverter, and the bypass switch is used for responding to the first control signal to be switched on, so that an alternating current power supply provides active power for a load through the bypass switch; the DC / AC inverter is in an inversion state in response to the second control signal, obtains energy from the DC energy storage equipment, and provides active power of the first set power for the load, so that the active power provided by the AC power supply for the load is smaller than the second set power. According to the uninterruptible power supply provided by the scheme, a rectifier part in a traditional uninterruptible power supply framework is omitted, only the inverter and the static bypass are included, the size of the uninterruptible power supply is reduced, and the equipment cost is reduced. Meanwhile, the direct-current energy storage equipment and the alternating-current power supply simultaneously provide active power for the load after passing through the DC / AC inverter, and peak load shifting of the power of the power grid side is achieved.

Description

Technical Field

[0001] This disclosure relates to the field of power technology, and more specifically, to an uninterruptible power supply and its control method, related equipment and systems. Background Technology

[0002] During the process of power supply system supplying power to load, power supply abnormalities often occur, causing the load to be unable to obtain stable and continuous power, thereby affecting the normal operation of the load.

[0003] To ensure the continuity and stability of power supply to loads, more and more power supply systems are equipped with UPS (uninterruptible power supply). However, with the surge in demand for AI (Artificial Intelligence) computing power, the single-point power capacity of data centers has increased dramatically, and the large size of traditional UPS cannot meet the deployment requirements of AI servers. Summary of the Invention

[0004] This disclosure provides an uninterruptible power supply and its control method, related equipment and system, which at least to some extent overcomes the technical problem that the large size of traditional UPS in related technologies cannot meet the deployment requirements of AI servers.

[0005] According to a first aspect of the present disclosure, an uninterruptible power supply (UPS) is provided, comprising: a bypass switch, a first terminal of which is connected to an AC power source, and a second terminal of which is connected to a load, for conducting in response to a first control signal; the AC power source provides active power to the load through the bypass switch; and a DC / AC (Direct Current / Alternating Current) inverter, a first terminal of which is connected to a DC energy storage device, and a second terminal of which is connected to the load, for engaging in an inversion state in response to a second control signal, acquiring energy from the DC energy storage device, and providing active power of a first set power to the load, such that the active power provided by the AC power source to the load is less than a second set power.

[0006] In some embodiments, the bypass switch is further configured to turn off in response to a third control signal; the DC / AC inverter is further configured to, in response to a fourth control signal, obtain energy from the DC energy storage device and provide all the required power to the load when the bypass switch is turned off; and the DC / AC inverter is further configured to, in response to a fifth control signal, provide reactive power to the load when the bypass switch is turned on.

[0007] In some embodiments, a DC / DC (Direct Current / Direct Current) converter is used to convert the output voltage of the DC energy storage device. The first terminal of the DC / DC converter is connected to the first terminal of the DC / AC inverter, and the second terminal of the DC / DC converter is connected to the DC energy storage device.

[0008] In some embodiments, the DC / AC inverter is a three-phase clamped inverter, and the phase difference of the PWM signals of any two phase clamped inverters is a first angle; each phase clamped inverter includes: a first transistor, a second transistor, a third transistor, a fourth transistor, a fifth transistor, a sixth transistor, a seventh transistor, an eighth transistor, a first inductor, a second inductor, and a first capacitor; the positive terminal of the DC energy storage device is connected to the first terminal of the first transistor and the first terminal of the second transistor, the second terminal of the first transistor is connected to the first terminal of the third transistor and the first terminal of the first inductor, the second terminal of the second transistor is connected to the first terminal of the fourth transistor and the first terminal of the second inductor, the negative terminal of the DC energy storage device is connected to the second terminal of the third transistor and the second terminal of the fourth transistor, the second terminal of the first inductor and the second terminal of the second inductor are connected to the load through a first connection point, and the second terminal of the first inductor and the second terminal of the second inductor are connected to the neutral line through the first capacitor; the second terminal of the first transistor is connected to the neutral line through the fifth transistor and the sixth transistor, and the second terminal of the second transistor is connected to the neutral line through the seventh transistor and the eighth transistor.

[0009] In some embodiments, it further includes: an equalization circuit; the equalization circuit includes a third inductor, a ninth transistor, and a tenth transistor; the positive terminal of the DC energy storage device is connected to the first terminal of the ninth transistor, and the negative terminal of the DC energy storage device is connected to the second terminal of the tenth transistor; the second terminal of the ninth transistor is connected to the first terminal of the tenth transistor and the first terminal of the seventh inductor, and the second terminal of the seventh inductor is connected to the neutral line.

[0010] In some embodiments, the DC / DC converter is a three-phase DC / DC converter, and the phase difference between the PWM signals of any two phases of the DC / DC converter is a first angle; wherein, each phase of the DC / DC converter includes: an eleventh transistor, a twelfth transistor, a thirteenth transistor, a fourteenth transistor, a fourth inductor, and a fifth inductor; the positive terminal of the DC energy storage device is connected to the first terminal of the fourth inductor, the second terminal of the fourth inductor is connected to the first terminals of the eleventh transistor and the twelfth transistor respectively, the second terminal of the eleventh transistor is connected to the first positive terminal of the DC / AC inverter, the second terminal of the twelfth transistor is connected to the neutral line, the negative terminal of the DC energy storage device is connected to the first terminal of the fifth inductor, the second terminal of the fifth inductor is connected to the first terminals of the thirteenth transistor and the fourteenth transistor respectively, the second terminal of the thirteenth transistor is connected to the first negative terminal of the DC / AC inverter, and the second terminal of the fourteenth transistor is connected to the neutral line.

[0011] In some embodiments, the system further includes: a controller connected to a bypass switch and a DC / AC inverter, respectively, configured to send a first control signal to the bypass switch and a second control signal to the DC / AC inverter when the AC power supply meets the power supply requirements and the combined power supply conditions are met; further configured to send a first control signal to the bypass switch and a fifth control signal to the DC / AC inverter when the AC power supply meets the power supply requirements but the uninterruptible power supply does not meet the combined power supply conditions; and further configured to send a third control signal to the bypass switch and a fourth control signal to the DC / AC inverter when the AC power supply does not meet the power supply requirements.

[0012] According to a second aspect of the present disclosure, a power system is provided, the power system including an uninterruptible power supply as described in any of the first aspects above.

[0013] According to a third aspect of the present disclosure, an uninterruptible power supply (UPS) control method is provided. The UPS includes: a bypass switch, a first terminal of which is connected to an AC power supply, and a second terminal of which is connected to a load; and a DC / AC inverter, a first terminal of which is connected to a DC energy storage device, and a second terminal of which is connected to the load. The method includes: detecting the power supply status of the AC power supply; if the detected AC power supply status meets the power supply requirements of the load, and the UPS meets the combined power supply conditions, sending a first control signal to the bypass switch and a second control signal to the DC / AC inverter; the first control signal is used to control the bypass switch to conduct, so that the AC power supply provides active power to the load through the bypass switch; the second control signal is used to control the DC / AC inverter to be in an inverter state, to obtain energy from the DC energy storage device, and to provide active power of a first set power to the load, such that the active power provided by the AC power supply to the load is less than a second set power.

[0014] In some embodiments, the method further includes: if the AC power supply status is detected as not meeting the power supply requirements of the load, sending a third control signal to the bypass switch and a fourth control signal to the DC / AC inverter; the third control signal is used to control the bypass switch to turn off; the fourth control signal is used to control the DC / AC inverter to obtain energy from the DC energy storage device and provide all the required power to the load; if the AC power supply is detected as meeting the power supply requirements, but the uninterruptible power supply does not meet the joint power supply conditions, sending a first control signal to the bypass switch and a fifth control signal to the DC / AC inverter; the fifth control signal is used to control the DC / AC inverter to provide reactive power to the load.

[0015] In some embodiments, the uninterruptible power supply (UPS) meets the combined power supply conditions including at least one of the following: the power demand of the load is greater than the power provided by the AC power supply, the state of charge (SOC) of the DC energy storage device is greater than the set SOC, the UPS operates within a set time period, and the estimated standby time of the DC energy storage device is greater than the set standby time.

[0016] In some embodiments, the first set power is determined based on a preset bypass percentage and the power requirements of the load.

[0017] According to a fourth aspect of the present disclosure, a controller for an uninterruptible power supply (UPS) is provided. The UPS includes: a bypass switch, a first terminal of which is connected to an AC power source, and a second terminal of which is connected to a load; a DC / AC inverter, a first terminal of which is connected to a DC energy storage device, and a second terminal of which is connected to the load; and a controller connected to the bypass switch and the DC / AC inverter. The controller includes: a status detection module for detecting the power supply status of the AC power source; and a signal transmission module for sending a first control signal to the bypass switch and a second control signal to the DC / AC inverter if the detected power supply status of the AC power source meets the power supply requirements of the load and the UPS meets the combined power supply conditions. The first control signal controls the bypass switch to be turned on so that the AC power source provides active power to the load through the bypass switch. The second control signal controls the DC / AC inverter to be in an inversion state, obtaining energy from the DC energy storage device and providing active power of a first set power to the load, such that the active power provided by the AC power source to the load is less than a second set power.

[0018] According to a fifth aspect of the present disclosure, an electronic device is provided, comprising: a processor; a memory for storing processor-executable instructions; wherein the processor is configured to execute the executable instructions to implement an uninterruptible power supply control method as described in any of the third aspects above.

[0019] According to a sixth aspect of the present disclosure, a computer-readable storage medium is provided, which, when the instructions in the computer-readable storage medium are executed by a processor of an electronic device, enables the electronic device to implement the uninterruptible power supply control method of any of the third aspects described above.

[0020] According to a seventh aspect of the present disclosure, a computer program product is provided, including a computer program that is executed by a processor using the uninterruptible power supply control method of any of the third aspects described above.

[0021] The uninterruptible power supply (UPS) provided in this embodiment includes a bypass switch and a DC / AC inverter. The bypass switch is activated in response to a first control signal, allowing the AC power supply to provide active power to the load through the bypass switch. The DC / AC inverter is in an inversion state in response to a second control signal, obtaining energy from a DC energy storage device and providing active power to the load at a first set power level, such that the active power provided by the AC power supply to the load is less than the second set power level. This UPS eliminates the rectifier section in traditional UPS architectures, including only an inverter and a static bypass, reducing the size of the UPS and lowering equipment costs. Simultaneously, the DC energy storage device, after passing through the DC / AC inverter, provides active power to the load simultaneously with the AC power supply, achieving peak shaving and valley filling of the grid-side power to avoid impacting the AC power supply due to AI load fluctuations.

[0022] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0023] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure. It is obvious that the drawings described below are merely some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0024] Figure 1 This is a schematic diagram of an uninterruptible power supply in a combined power supply mode, according to an exemplary embodiment.

[0025] Figure 2 This is a schematic diagram of an uninterruptible power supply in battery mode according to an exemplary embodiment.

[0026] Figure 3 This is a schematic diagram of an uninterruptible power supply in primary mode, according to an exemplary embodiment.

[0027] Figure 4This is a schematic diagram of the structure of another uninterruptible power supply according to an exemplary embodiment.

[0028] Figure 5 This is a schematic diagram of the structure of another uninterruptible power supply according to an exemplary embodiment.

[0029] Figure 6 This is a schematic diagram of the structure of another uninterruptible power supply according to an exemplary embodiment.

[0030] Figure 7 This is a circuit implementation diagram of an uninterruptible power supply according to an exemplary embodiment.

[0031] Figure 8 This is a circuit diagram illustrating another uninterruptible power supply according to an exemplary embodiment.

[0032] Figure 9 This is a circuit implementation diagram of another uninterruptible power supply according to an exemplary embodiment.

[0033] Figure 10 This is a circuit diagram of a Boost converter circuit according to an exemplary embodiment.

[0034] Figure 11 This is a circuit diagram of a Buck-Boost buck-boost circuit according to an exemplary embodiment.

[0035] Figure 12 This is a schematic diagram illustrating the structure of a lithium battery directly connected to a bus according to an exemplary embodiment.

[0036] Figure 13 The diagram illustrates the structure of an electric power system according to an exemplary embodiment.

[0037] Figure 14 This is a flowchart illustrating an uninterrupted control method according to an exemplary embodiment.

[0038] Figure 15 This is a schematic diagram of a settings page for combined power supply conditions, according to an exemplary embodiment.

[0039] Figure 16 This is a flowchart illustrating another uninterrupted control method according to an exemplary embodiment.

[0040] Figure 17 This is a block diagram illustrating a controller according to an exemplary embodiment.

[0041] Figure 18 This is a schematic diagram of the structure of an electronic device according to an exemplary embodiment. Detailed Implementation

[0042] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, they are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar parts, and therefore repeated descriptions of them will be omitted.

[0043] The features, structures, or characteristics described in this disclosure can be combined in any suitable manner in one or more embodiments. Numerous specific details are provided in the following description to give a thorough understanding of embodiments of this disclosure. However, those skilled in the art will recognize that the technical solutions of this disclosure can be practiced with one or more specific details omitted, or other methods, components, apparatuses, steps, etc., can be employed. In other instances, well-known methods, apparatuses, implementations, or operations are not shown or described in detail to avoid obscuring various aspects of this disclosure.

[0044] The accompanying drawings are merely illustrative of this disclosure, and the same reference numerals in the drawings denote the same or similar parts, thus omitting repeated descriptions of them. Some block diagrams shown in the drawings do not necessarily correspond to physically or logically independent entities. These functional entities may be implemented in software, in at least one hardware module or integrated circuit, or in different network and / or processor devices and / or microcontroller devices.

[0045] The flowchart shown in the accompanying drawings is merely illustrative and does not necessarily include all content and steps, nor does it require execution in the described order. For example, some steps may be broken down, while others may be combined or partially combined; therefore, the actual execution order may change depending on the specific circumstances.

[0046] In this specification, the terms “a,” “an,” “the,” “the,” and “at least one” are used to indicate the presence of at least one element / component / etc.; the terms “comprising,” “including,” and “having” are used to indicate an open-ended inclusion and to mean that there may be other elements / components / etc. in addition to the listed elements / components / etc.; the terms “first,” “second,” and “third,” etc., are used only as markings and are not a limitation on the number of objects.

[0047] Figure 1 A schematic diagram of an uninterruptible power supply (UPS) according to an embodiment of this disclosure is shown, such as... Figure 1As shown, the uninterruptible power supply 10 includes a bypass switch 110 and a DC / AC inverter 120. The first terminal of the bypass switch 110 is connected to the AC power supply 20, and the second terminal of the bypass switch 110 is connected to the load 30. The first terminal of the DC / AC inverter 120 is connected to the DC energy storage device 40, and the second terminal of the DC / AC inverter 120 is connected to the load 30.

[0048] In this configuration, the bypass switch 110 is turned on in response to the first control signal, and the AC power supply 20 provides active power to the load 30 through the bypass switch 110. The DC / AC inverter 120 is turned on in response to the second control signal, and the DC / AC inverter 120 is in the inverter state, obtaining energy from the DC energy storage device 40 and providing active power of the first set power to the load 30, so that the active power provided by the AC power supply 20 to the load 30 is less than the second set power.

[0049] An uninterruptible power supply (UPS) is a power electronic device that can switch the power supply to a DC energy storage device to maintain the continuous operation of the load when the AC input is abnormal. The biggest difference between the UPS 10 provided in this embodiment and a traditional UPS is that its architecture omits the rectifier and only includes a bypass switch 110 and a DC / AC inverter 120.

[0050] An AC power source refers to an external power supply device or system capable of providing sinusoidal alternating current (AC) energy to supply standard AC power to a load. For example, an AC power source can be the public power grid, also known as mains power or grid power. An AC power source can also be an AC generator driven by an internal combustion engine, or a renewable energy generation system. For example, a renewable energy generation system can include grid-connected photovoltaic inverters or wind power inverters.

[0051] A DC energy storage device is a DC source device used to store electrical energy. The DC energy storage device can be a battery or battery pack, or it can be a supercapacitor or other types of DC energy storage system. For example, a DC energy storage device is a lithium battery pack that outputs a DC voltage of 800-850V, allowing the DC bus voltage to reach 900V.

[0052] The bypass switch 110 can be understood as an electrical switching element connected between the AC power source and the load, used to establish or disconnect the path for the AC power source to directly supply power to the load. For example... Figure 1 As shown, the first terminal of the bypass switch 110 is electrically connected to the AC power supply 20, and the second terminal of the bypass switch 110 is electrically connected to the load 30. The bypass switch 110 can be a static switch or an electromechanical switch. For example, the bypass switch 110 is a static switch composed of thyristors to improve switching speed.

[0053] A DC / AC inverter is a power conversion device that converts direct current (DC) into alternating current (AC). For example... Figure 1 As shown, the first terminal of the DC / AC inverter 120 is connected to the DC energy storage device 40, and the second terminal of the DC / AC inverter 120 is connected to the load 30. The operating state of the DC / AC inverter 120 is controlled by a controller. In practical applications, depending on the specific circuit design, the DC / AC inverter 120 may include a full-bridge inverter, a half-bridge inverter, or a three-phase inverter, etc.

[0054] The uninterruptible power supply provided in this disclosure has three main power supply modes: combined power supply mode, main power supply mode, and battery mode.

[0055] The first control signal that controls the bypass switch 110 to turn on, and the second control signal that controls the DC / AC inverter 120, work together to control the uninterruptible power supply to operate in the combined power supply mode. In the combined power supply mode, the AC power supply and the DC / AC inverter 120 in the inverting state obtain energy from the DC energy storage device 40, and at the same time provide active power to the load 30.

[0056] The first control signal is a conduction signal, used to control the bypass switch 110 to close, so that the AC power supply 20 is directly connected to the load 30. The second control signal includes an inverter command and a power command. The inverter command is used to control the DC / AC inverter 120 to operate in inverter mode, and the power command is used to control the target active power value output by the DC / AC inverter 120, i.e., the first set power.

[0057] In the combined power supply mode, the bypass switch 110 turns on in response to the first control signal, establishing a power supply path from the AC power source 20 to the load 30. At the same time, the DC / AC inverter 120 responds to the second control signal, enters the inverter state, and obtains energy from the DC energy storage device 40 according to the power command, and stably outputs active power to the load 30, and the output active power is the first set power P1.

[0058] In the combined power supply mode, load 30 is powered by AC power supply 20 and DC / AC inverter 120 connected in parallel. The total power P of load 30 is shared by both power supplies, i.e., P = P1 + Pgrid, where Pgrid is the actual active power provided by the AC power. In this embodiment, the first active power P1 can be dynamically adjusted through a second control signal, thereby dynamically adjusting the active power Pgrid required by the AC power supply to be less than the second active power P2. In other words, the control objective is to make the active power Pgrid output by the AC power supply less than the second set power P2.

[0059] By using the first and second control signals, the uninterruptible power supply (UPS) is transformed from a passive electrical consumer into an active power dispatch manager. That is, regardless of load changes, the power drawn from the AC power source must not exceed a second set power P2. Any power demand exceeding the second set power P2 is dynamically supplemented by the DC energy storage device through a DC / AC inverter.

[0060] The uninterruptible power supply (UPS) provided by this solution eliminates the rectifier section in traditional UPS architectures, consisting only of an inverter and a static bypass, thus reducing the size of the UPS and lowering equipment costs. Simultaneously, the DC energy storage device, after passing through a DC / AC inverter, simultaneously provides active power to the load along with the AC power supply, achieving peak shaving and valley filling of grid-side power to prevent AI load fluctuations from impacting the AC power supply.

[0061] In some embodiments, the bypass switch 110 is further configured to turn off in response to a third control signal; the DC / AC inverter 120 is further configured to, in response to a fourth control signal, obtain energy from the DC energy storage device 40 and provide all the required power to the load 30 when the bypass switch 110 is turned off; the DC / AC inverter 120 is further configured to, in response to a fifth control signal, provide reactive power to the load when the bypass switch 110 is turned on.

[0062] In one implementation, such as Figure 2 As shown, the bypass switch 110 is also used to turn off in response to a third control signal; the DC / AC inverter 120 is also used to, in the case that the bypass switch 110 is turned off, in response to a fourth control signal to obtain energy from the DC energy storage device 40 and provide all the required power to the load 30.

[0063] When an AC power supply malfunctions, the system switches from combined power supply mode or primary mode to battery mode via the third and fourth control signals. Battery mode, also known as battery backup power supply mode, involves the DC energy storage device providing all power to the load via the DC / AC inverter 120, while the AC power supply ceases to provide active power. AC power supply malfunctions include, but are not limited to: power outages, voltage fluctuations exceeding a threshold, and frequency anomalies.

[0064] In response to the third control signal, the bypass switch 110 quickly switches from the on state to the off state, cutting off the connection between the AC power supply and the load 30. This effectively prevents the impact of a faulty power supply on the load and prevents the electrical energy generated by the DC / AC inverter 120 from flowing back into the grid, causing damage to grid equipment or safety accidents. In response to the fourth control signal, the DC / AC inverter 120 enters the inversion state and is ready to provide all the power required by the load. Its power control target is immediately updated from the first set power in the combined power supply mode or the reactive power in the primary mode to the real-time total power demand of the load.

[0065] The inverter dynamically adjusts its output according to the instructions of the fourth control signal so that the load can obtain stable and uninterrupted power under any power demand.

[0066] In this embodiment, when the AC power supply is abnormal, the third and fourth control signals enable the switch from the normal combined power supply mode or the main power supply mode to the battery mode. The DC energy storage device provides all the power requirements of the load through the DC / AC inverter 120, providing uninterrupted power to the load.

[0067] In one implementation, such as Figure 3 As shown, the DC / AC inverter 120 is also used to provide reactive power to the load in response to a fifth control signal when the bypass switch 110 is turned on.

[0068] In primary mode, the AC power supply provides all the active power required by the load, and the bypass switch 110 remains on in response to the first control signal. The AC power supply 20 is directly connected to the load 30 through the on-state bypass switch 110. The DC / AC inverter 120 enters reactive power compensation mode in response to the fifth control signal. In this mode, the DC / AC inverter 120 outputs a reactive current, meaning that all the active power required by the load 30 is provided by the AC power supply 20 through the bypass switch 110, while the reactive power required by the load 30 is generated and provided locally by the DC / AC inverter 120. At this time, from the grid side, the AC power supply 20 only needs to provide active current, and its output current is in phase with the voltage, making the overall power factor of the system approach 1. In this mode, the uninterruptible power supply operates in primary mode with an efficiency of 99%.

[0069] It should be noted that, Figure 1 , Figure 2 , Figure 3 A thick solid black line indicates that active power flows through the path, a thick dashed black line indicates that reactive power flows through the path, and a thin solid black line indicates that the path is broken.

[0070] In this embodiment, reactive power compensation by the DC / AC inverter 120 can significantly improve the power factor on the grid side, reduce transmission losses caused by reactive current in the line, and improve voltage stability. Furthermore, because the time between the DC / AC inverter 120 switching from reactive power compensation mode to inverter mode is extremely short, the load will not experience power loss.

[0071] Through various control signals, the uninterruptible power supply can switch between various modes in less than 2ms, and the load will not lose power.

[0072] Based on the aforementioned uninterruptible power supply, the structure of the uninterruptible power supply in this embodiment has been optimized, such as... Figure 4 As shown, the optimized uninterruptible power supply 10 also includes a DC / DC converter 130, wherein the first terminal of the DC / DC converter 130 is connected to the first terminal of the DC / AC inverter 120, and the second terminal of the DC / DC converter 130 is connected to the DC energy storage device 40; the DC / DC converter 130 is used to convert the output voltage of the DC energy storage device 40.

[0073] A DC / DC converter is a power electronic device that converts direct current (DC) at a first voltage level to DC at a second voltage level. In this embodiment, such as... Figure 4 As shown, the first terminal of the DC / DC converter 130 is connected to the DC side of the DC / AC inverter 120, and the second terminal of the DC / DC converter 130 is connected to the DC energy storage device 40. The DC / DC converter 120 may include, but is not limited to: a boost converter, a buck converter, a buck-boost converter, a non-isolated converter, and an isolated converter.

[0074] In the combined power supply mode, the bypass switch 110 is turned on in response to the first control signal, and the DC / AC inverter 120 is in inverter mode in response to the second control signal, providing active power of the first set power to the load. The DC / DC converter 130 starts working in response to the control command it receives. The DC / DC converter 130 obtains energy from the DC energy storage device 40 and converts and stabilizes its output voltage at the optimal DC bus voltage required by the DC / AC inverter 120. At the same time, the DC / DC converter 130 controls its output power to match the power demand of the DC / AC inverter 120. This allows the DC / AC inverter 120 to operate at the optimal DC voltage, thereby improving conversion efficiency.

[0075] In battery mode, bypass switch 110 is turned off in response to a third control signal. DC / AC inverter 120 responds to a fourth control signal to provide all the required power to the load. DC / DC converter 130 operates continuously, maintaining a stable DC bus voltage regardless of battery voltage drops, thereby ensuring that the amplitude and frequency of the AC voltage output by DC / AC inverter 120 remain stable, thus ensuring that power quality is unaffected by battery charge.

[0076] In primary mode, bypass switch 110 is turned on, and DC / AC inverter 120 responds to the fifth control signal to provide reactive power to the load. DC / DC converter 130 only needs to provide a small amount of power to cover the operating losses of the DC / AC inverter itself, and its operating state is in the light-load high-efficiency range.

[0077] In this embodiment, the DC bus voltage is stabilized by a DC / DC converter, so that the DC / AC inverter always operates in the region with the highest efficiency, ensuring high quality of the output AC power.

[0078] Based on the aforementioned uninterruptible power supply, the structure of the uninterruptible power supply in this embodiment has been optimized, such as... Figure 5 As shown, the optimized uninterruptible power supply 10 also includes a controller 140, such as... Figure 5 As shown, the controller 140 is connected to the bypass switch 110 and the DC / AC inverter 120 respectively. It is used to send a first control signal to the bypass switch 110 and a second control signal to the DC / AC inverter 120 when it detects that the AC power supply 20 meets the power supply requirements and the combined power supply conditions are met; it is also used to send a first control signal to the bypass switch 110 and a fifth control signal to the DC / AC inverter 120 when it detects that the AC power supply 20 meets the power supply requirements but the uninterruptible power supply does not meet the combined power supply conditions; it is also used to send a third control signal to the bypass switch 110 and a fourth control signal to the DC / AC inverter 120 when it detects that the AC power supply does not meet the power supply requirements.

[0079] The controller detects the AC power supply status. If the AC power supply status meets the load's power requirements and the uninterruptible power supply (UPS) meets the combined power supply conditions, it sends a first control signal to the bypass switch and a second control signal to the DC / AC inverter. The first control signal controls the bypass switch to turn on, allowing the AC power supply to provide active power to the load through the bypass switch. The second control signal controls the DC / AC inverter to be in inversion mode, obtaining energy from the DC energy storage device and providing active power to the load at a first set power level, ensuring that the active power provided by the AC power supply to the load is less than the second set power level. If the AC power supply status does not meet the load's power requirements, a third control signal is sent to the bypass switch and a fourth control signal is sent to the DC / AC inverter. The third control signal controls the bypass switch to turn off; the fourth control signal controls the DC / AC inverter to obtain energy from the DC energy storage device and provide all the required power to the load. If the AC power supply fails to meet the power demand and the uninterruptible power supply fails to meet the combined power supply conditions, a first control signal is sent to the bypass switch and a fifth control signal is sent to the DC / AC inverter. The fifth control signal is used to control the DC / AC inverter to provide reactive power to the load.

[0080] Based on the aforementioned uninterruptible power supply, the structure of the uninterruptible power supply in this embodiment has been optimized, such as... Figure 6 As shown, the optimized uninterruptible power supply 10 also includes a physical switch 150, the first terminal of which is connected to an AC power source, and the second terminal of which is connected to a load. The physical switch 150 is mounted on the casing of the uninterruptible power supply.

[0081] Physical switch 150, also known as an external bypass switch, is manually operated by the user for maintenance. When maintaining, repairing, or replacing the battery in the uninterruptible power supply (UPS), manually closing physical switch 150 completely disconnects the load from the UPS internal circuitry. AC power then directly supplies power to the load through physical switch 150, ensuring uninterrupted power supply during UPS maintenance. It should be noted that during normal UPS operation, physical switch 150 is normally open; the user manually closes physical switch 150 when performing maintenance, repairs, or battery replacement.

[0082] Based on the aforementioned uninterruptible power supply, the structure of the uninterruptible power supply in this embodiment has been optimized, such as... Figure 7 As shown, DC / AC inverter 120 is a three-phase clamped inverter, and the phase difference between the PWM signals of any two phases of the clamped inverter is the first angle.

[0083] In an ideal three-phase balanced system, the phase difference between the phase voltages is 120 degrees. To ensure that the three-phase current output by the DC / AC inverter 120 is symmetrical and sinusoidal, preferably, the first angle is 120 degrees. In other words, the phase difference between the PWM signals of any two phase clamped inverters is 120 degrees; that is, the phase difference between the PWM signals of phase A and phase B is 120 degrees, the phase difference between the PWM signals of phase B and phase C is 120 degrees, and the phase difference between the PWM signals of phase C and phase A is 120 degrees.

[0084] Furthermore, in certain scenarios, to compensate for the imbalance of the load voltage itself or to achieve specific control objectives, the phase of each phase clamp inverter is adjusted slightly and adaptively. In this case, the phase difference between the PWM signals of each phase clamp inverter is no longer strictly 120 degrees, but fluctuates within a very small range around 120 degrees.

[0085] Each phase clamped inverter includes: a first transistor M1, a second transistor M2, a third transistor M3, a fourth transistor M4, a fifth transistor M5, a sixth transistor M6, a seventh transistor M7, an eighth transistor M8, a first inductor L1, a second inductor L2, and a first capacitor C1.

[0086] The positive terminal BAT+ of the DC energy storage device is connected to the first terminal of the first transistor M1 and the first terminal of the second transistor M2. The second terminal of the first transistor M1 is connected to the first terminal of the third transistor M3 and the first terminal of the first inductor L1. The second terminal of the second transistor M2 is connected to the first terminal of the fourth transistor M4 and the first terminal of the second inductor L2. The negative terminal BAT- of the DC energy storage device is connected to the second terminal of the third transistor M3 and the second terminal of the fourth transistor M4. The second terminals of the first inductor L1 and the second terminals of the second inductor L2 are connected to the load through the first connection point. The second terminals of the first inductor L1 and the second terminals of the second inductor L2 are connected to the neutral line N through the first capacitor C1.

[0087] The second terminal of the first transistor M1 is connected to the neutral line N through the fifth transistor M5 and the sixth transistor M6, and the second terminal of the second transistor M2 is connected to the neutral line N through the seventh transistor M7 and the eighth transistor M8.

[0088] like Figure 7 As shown, the circuit topology of each phase clamping inverter is the same. Furthermore, the output terminal of the A-phase clamping inverter is connected to the first phase input terminal OUT-L1 of the load, the output terminal of the B-phase clamping inverter is connected to the second phase input terminal OUT-L2 of the load, and the output terminal of the C-phase clamping inverter is connected to the third phase input terminal OUT-L3 of the load.

[0089] like Figure 7 As shown, AC power supply 20 is a three-phase AC power supply. The first phase IN-L1 of AC power supply 20, after passing through bypass switch 110, is connected to the first phase input terminal OUT_L1 of the load through inductor L, fuse FU, and fuse PS in the first phase branch. The second phase IN-L2 of AC power supply 20, after passing through bypass switch 110, is connected to the second phase input terminal OUT_L2 of the load through inductor L, fuse FU, and fuse PS in the second phase branch. The third phase IN-L3 of AC power supply 20, after passing through bypass switch 110, is connected to the third phase input terminal OUT_L3 of the load through inductor L, fuse FU, and fuse PS in the third phase branch.

[0090] Furthermore, such as Figure 7 As shown, the positive terminal BAT+ of the DC energy storage device 40 is connected to the positive terminal of the DC / AC inverter 120 through the fuse FU and the fuse PS connected in series with it, and the negative terminal BAT- of the DC energy storage device 40 is connected to the negative terminal of the DC / AC inverter 120 through the fuse FU and the fuse PS connected in series with it.

[0091] Furthermore, such as Figure 7 As shown, the positive terminal BAT+ and the negative terminal BAT- of the DC energy storage device 40 are connected in parallel with a capacitor circuit. The capacitor circuit includes two capacitors C connected in series, and the connection point of the two capacitors C is connected to the neutral point.

[0092] The transistors described in this embodiment are all controlled semiconductor switching devices. In other words, the transistors respond to a control signal, rapidly turning on or off to cut the direct current into the desired alternating current waveform. Exemplary examples include, but are not limited to: IGBTs (Insulated Gate Bipolar Transistors), MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistors), and silicon carbide MOSFETs. Optionally, the transistors may include silicon carbide MOSFETs to improve the voltage withstand capability of the DC / AC inverter.

[0093] In this embodiment, the DC energy storage device 40 is directly connected to the bus to improve the withstand voltage capability of the bus capacitor and power components. Specifically, the positive terminal BAT+ of the DC energy storage device 40 is directly connected to the positive terminal of the internal DC bus of the DC / AC inverter 120 via the DC bus; similarly, the negative terminal BAT- of the DC energy storage device 40 is directly connected to the negative terminal of the internal DC bus of the DC / AC inverter 120 via the DC bus, without any intermediate power conversion stage.

[0094] In this embodiment, a three-phase AC load is used as an example for explanation. The aforementioned DC / AC inverter 120 is a three-phase T-type three-level inverter topology. The DC energy storage device 40 provides a DC voltage Vdc, with its positive terminal being BAT+ and its negative terminal being BAT-. The DC / AC inverter 120 is a three-phase inverter, with each phase consisting of four transistors forming a T-type bridge arm. Two inductors and one capacitor form a dual-inductor LC filter network to filter the output voltage of each phase.

[0095] Taking the first phase bridge arm, consisting of transistors M1, M2, M3, and M4, as an example, the working principle of the first phase is explained. By controlling the on / off combinations of the four transistors, the first phase bridge arm can generate three voltage levels at the output. First state: Transistor M1 is on, while transistors M2, M3, and M4 are off. The midpoint of the bridge arm is clamped to the positive DC potential (+Vdc / 2) through the on-state transistor M1. Current flows to the load through the LC filter, resulting in a positive output voltage of +Vdc / 2. Second state: Transistors M3 and M4 are on, while transistors M1 and M2 are off. The midpoint of the bridge arm is short-circuited to the neutral point through the on-state transistors M3 and M4, clamping the potential to 0V, thus outputting a zero voltage level. Third state: Switching state: Transistor M2 is on, while transistors M1, M3, and M4 are off. The midpoint of the bridge arm is clamped to the negative DC potential (-Vdc / 2) through the on-state transistor M2. The current flows through the LC filter to the load, and the output is a negative level -Vdc / 2.

[0096] The working principles of the second and third phases are the same as those of the first phase, except that they lag behind each other by 120 degrees in phase. In this embodiment, the working principles of the second and third phases will not be described in detail.

[0097] By using sinusoidal pulse width modulation (SPWM), the duty cycles of the three voltage levels mentioned above are controlled to change sinusoidally. After the PWM waveform is filtered, the high-frequency components are removed, and a smooth sinusoidal voltage is output to the load. The circuit structures of the first, second, and third phases are exactly the same, but the PWM waves controlling their switching transistors are sequentially delayed by 120 degrees in phase, thus synthesizing a symmetrical three-phase AC power.

[0098] In this embodiment, the low-voltage stress characteristics of the T-type three-level inverter can be directly adapted to battery packs with higher voltage levels, without the need to select expensive components with extremely high voltage resistance for the inverter.

[0099] In this embodiment, based on the three-phase T-type three-level inverter, two independent neutral line control branches are added to each phase. Taking the first phase as an example, the main power channel consists of a T-shaped bridge arm formed by the first transistor M1, the second transistor M2, the third transistor M3, and the fourth transistor M4. After filtering by the first inductor L1, the second inductor L2, and the first capacitor C1, the output is sent to the first input terminal of the load. The second terminal of the first transistor M1 (midpoint of the upper bridge arm) is connected to the neutral line N through the fifth transistor M5 and the sixth transistor M6, forming the first neutral line control branch. The second terminal of the second transistor M2 (midpoint of the lower bridge arm) is connected to the neutral line N through the seventh transistor M7 and the eighth transistor M8, forming the second neutral line control branch. The first, second, and third phases have identical structures, forming a completely symmetrical three-phase four-wire system.

[0100] When a three-phase T-type three-level inverter supplies power to an unbalanced load, it can cause asymmetry in the three-phase output voltage, with the voltage of the lightly loaded phase rising and the voltage of the heavily loaded phase dropping, severely affecting equipment operation. The neutral branch provides a controlled low-impedance loop for the zero-sequence component (i.e., neutral current) in the unbalanced current. Through active control, the neutral point potential can be stabilized, ensuring that the three-phase output voltage remains balanced and stable.

[0101] Taking phase A as an example, when the neutral line needs to be injected with positive current, the fifth transistor M5 and the sixth transistor M6 are turned on, applying the potential of the upper midpoint to the neutral line. When the neutral line needs to be injected with negative current, the seventh transistor M7 and the eighth transistor M8 are turned on, applying the potential of the lower midpoint to the neutral line. The working principle of the second and third phases is the same as that of the first phase, and can be referred to the above description, which will not be repeated in this embodiment.

[0102] It should be noted that the fifth transistor M5, the sixth transistor M6, the seventh transistor M7, and the eighth transistor M8 cannot be turned on simultaneously, otherwise it will cause a short circuit between the positive and negative DC bus.

[0103] Based on the aforementioned uninterruptible power supply, the structure of the uninterruptible power supply in this embodiment has been optimized, such as... Figure 8 As shown, an equalization circuit 160 is provided between the DC energy storage device 40 and the DC / AC inverter 120. The equalization circuit 160 includes: a third inductor L3, a ninth transistor M9, and a tenth transistor M10; the positive terminal of the DC energy storage device 40 is connected to the first terminal of the ninth transistor M9, and the negative terminal of the DC energy storage device 40 is connected to the second terminal of the tenth transistor M10; the second terminal of the ninth transistor M9 is connected to the first terminal of the tenth transistor M10 and the first terminal of the third inductor L3, and the second terminal of the third inductor L3 is connected to the neutral line.

[0104] When the inverter DC bus voltage becomes too high due to sudden load changes or other reasons, the balancing circuit operates in Buck mode. In the first stage, transistor M9 is turned on and transistor M10 is turned off. Current flows from the positive terminal of the DC energy storage device through transistor M9 and inductor L3 to the neutral line, where inductor L3 stores energy. In the second stage, transistor M9 is turned off, and the body diode or active conduction of transistor M10 provides a freewheeling path. The current in inductor L3 continues to flow through the neutral line and decreases linearly, releasing energy. The amount of current injected into the neutral line can be controlled by adjusting the duty cycle of transistor M9. In Buck mode, excess energy on the DC side is extracted and injected into the inverter's neutral line, thereby reducing the DC bus voltage.

[0105] When the DC bus voltage is low, the circuit operates in Boost mode. In the first stage, the tenth transistor M10 is turned on and the ninth transistor M9 is turned off. Current flows from the neutral line through the third inductor L3 and the tenth transistor M10 to the negative terminal of the DC energy storage device, where the inductor stores energy. In the second stage, the tenth transistor M10 is turned off, and the body diode or active conduction of the ninth transistor M9 provides an energy feedback path. The current in the third inductor L3 is fed back to the DC side through the DC positive terminal, drawing energy from the neutral line N and feeding it back to the DC side to replenish the DC bus and boost the DC voltage.

[0106] The balancing circuit maintains DC bus voltage stability through bidirectional energy transfer. When the DC bus voltage is detected to be too high, Buck mode is activated to release excess energy; when the DC bus voltage is too low, Boost mode is activated to replenish energy. This regulates the stability of the inverter voltage.

[0107] Based on the above embodiments, such as Figure 9 As shown, the DC / DC converter is a three-phase DC / DC converter, and the phase difference between any two phases of the PWM signal of the DC / DC converter is the first angle.

[0108] In an ideal three-phase balanced system, the phase difference between the phase voltages is 120 degrees. To ensure that the three-phase currents output by the DC / DC converter are symmetrical and sinusoidal, the first phase angle is preferably 120 degrees. In other words, the phase difference between the PWM signals of any two phases of the DC / DC converter is 120 degrees; that is, the phase difference between the PWM signals of phase A and phase B is 120 degrees, the phase difference between the PWM signals of phase B and phase C is 120 degrees, and the phase difference between the PWM signals of phase C and phase A is 120 degrees.

[0109] Each phase of the DC / DC converter includes: eleventh transistor M11, twelfth transistor M12, thirteenth transistor M13, fourteenth transistor M14, fourth inductor L4, and fifth inductor L5.

[0110] The positive terminal BAT+ of the DC energy storage device is connected to the first terminal of the fourth inductor L4. The second terminal of the fourth inductor L4 is connected to the first terminal of the eleventh transistor M11 and the first terminal of the twelfth transistor M12. The second terminal of the eleventh transistor M11 is connected to the first positive terminal of the DC / AC inverter. The second terminal of the twelfth transistor M12 is connected to the neutral line N. The negative terminal of the DC energy storage device is connected to the first terminal of the fifth inductor L5. The second terminal of the fifth inductor L5 is connected to the first terminal of the thirteenth transistor M13 and the first terminal of the fourteenth transistor M14. The second terminal of the thirteenth transistor M13 is connected to the first negative terminal of the DC / AC inverter. The second terminal of the fourteenth transistor M14 is connected to the neutral line N.

[0111] When the DC energy storage device supplies power to the DC / AC inverter (DC bus), the DC / DC converter 130 operates in buck mode. The operation of the first phase is as follows: First stage: The eleventh transistor M11 is turned on, and the twelfth transistor M12, thirteenth transistor M13, and fourteenth transistor M14 are turned off. The current path is: positive terminal of the DC energy storage device, fourth inductor L4, eleventh transistor M11, and the first positive terminal of the DC / AC converter. At this time, the fourth inductor L4 stores magnetic energy, and the current increases linearly. Second stage: The eleventh transistor M11 is turned off, the thirteenth transistor M13 is turned on, and the twelfth transistor M12 and fourteenth transistor M14 are turned off. After the eleventh transistor M11 is turned off, the fourth inductor L4 generates a reverse electromotive force because the current cannot change abruptly, forcing the current to freewheel through the thirteenth transistor M13. The current path is: fourth inductor L4, positive terminal of DC / AC inverter, inside DC / AC inverter, negative terminal of DC / AC inverter, thirteenth transistor M13, fifth inductor L5, negative terminal of DC energy storage device, inside DC energy storage device, positive terminal of DC energy storage device. In the second stage, the fourth inductor L4 releases magnetic energy and supplies power to the DC / AC side together with the DC energy storage device. The current in the fourth inductor L4 increases linearly, storing magnetic energy.

[0112] The switching timing of the second and third phases differs from that of the first phase by 120°. Through multi-phase interleaving, input / output current ripple is reduced, power quality is improved, and the power pressure of single-phase alternating is distributed, thereby improving the overall power density and efficiency.

[0113] In one possible implementation, the DC / DC converter 130 can be adopted as follows: Figure 10 The Boost converter circuit shown can also be used as follows: Figure 11The Buck-Boost buck-boost circuit shown is an example. Additionally, it can be used as follows... Figure 12 As shown, instead of using a DC / DC converter, a lithium battery is directly connected to the bus, which improves the voltage withstand capability of the bus capacitor and power components.

[0114] The uninterruptible power supply (UPS) provided in this embodiment has the following advantages: Low cost: The rectifier section is reduced, resulting in lower equipment cost. High efficiency: It mainly operates in bypass mode, achieving 99% efficiency. High reliability: Various mode switching can be achieved within 2ms, ensuring no power loss to the load. Small footprint: Fewer components allow for a smaller overall equipment size. Support for higher voltage lithium battery packs: The bus voltage can reach 900V, accommodating 850V battery packs.

[0115] Combined power supply function: Combined with a high-voltage lithium battery pack, it can better cope with load fluctuations, especially the fluctuations in different frequency bands brought by AI servers.

[0116] Adaptable to more application scenarios: Can be used as an 800V input inverter.

[0117] Compared to traditional UPS systems, the uninterruptible power supply provided in this embodiment has the following advantages: Efficiency can be improved by 1% to 2%, reducing OPEX operating costs; construction costs can be reduced by more than 25%, saving on electromechanical investment; floor space can be reduced by more than 15%, saving building area and civil engineering investment costs; it can connect to lithium battery packs of up to 850V, adopting a combined power supply mode, which can improve IT output (more IT servers can be installed with the same power capacity), thereby reducing monthly rental costs; combined with a lithium battery system, it can solve the problem of AI load fluctuation, reduce the power distribution capacity of upstream and downstream stages, and reduce CAPEX investment; it can be used as an 800V HVDC output inverter, solving the problem that power loads cannot use 800V DC power supply, and can share lithium batteries, eliminating the need to set up a separate lithium battery for power loads, reducing investment costs.

[0118] Based on the same inventive concept, this disclosure also provides a power system, which includes any of the above-mentioned uninterruptible power supplies.

[0119] In some embodiments, such as Figure 13As shown, the AC / DC hybrid power supply system includes: an AC power supply 1310, a transformer 1320, and the AC power output from the AC power supply 1310 is processed by the transformer 1320 to provide three-phase input power. An 800V HVDC system 1330 converts the input three-phase power into 800V DC power, which is directly supplied to the 800V DC load 1340 on one hand; on the other hand, it connects to a lithium battery pack 1350 for energy storage or replenishment, ensuring the stability of the DC power supply. After the 800V DC power is input to the uninterruptible power supply 10, it is converted into 380V AC power to supply the 380VAC load 30. Simultaneously, a 380VAC bypass line serves as a backup path for AC power supply, further improving the reliability of the AC power supply.

[0120] Based on the same inventive concept, this disclosure also provides an uninterruptible power supply (UPS) control method, which is used to control any of the UPSs described above. The circuit structure of the UPS is as shown above and will not be repeated in this embodiment.

[0121] like Figure 14 As shown, the uninterruptible power supply control method includes steps S1402-S1404.

[0122] S1402, Detect the power supply status of the AC power supply.

[0123] In one possible implementation, detecting the power supply status of the AC power supply includes at least one of the following: detecting whether the output voltage amplitude of the AC power supply is within the rated allowable range (e.g., ±10%); detecting whether the frequency of the AC power supply is near the standard frequency (e.g., 50Hz ± 0.5Hz); detecting whether the total harmonic distortion rate of the output voltage waveform of the AC power supply is lower than a set threshold; and detecting whether there is a momentary interruption or phase jump in the output voltage of the AC power supply.

[0124] S1404. If the AC power supply status is detected to meet the power supply requirements of the load, and the uninterruptible power supply meets the joint power supply conditions, a first control signal is sent to the bypass switch, and a second control signal is sent to the DC / AC inverter. The first control signal is used to control the bypass switch to be turned on, so that the AC power supply provides active power to the load through the bypass switch. The second control signal is used to control the DC / AC inverter to be in the inversion state, to obtain energy from the DC energy storage device, and to provide active power of a first set power to the load, so that the active power provided by the AC power supply to the load is less than the second set power.

[0125] When all the electrical parameters tested above are within the normal operating range allowed by the load equipment, the power supply requirements of the load are deemed met. This ensures that the combined power supply mode is only activated when the output power quality of the AC power supply is sufficiently good, thus avoiding the introduction of unstable power into the load.

[0126] In some embodiments, the uninterruptible power supply (UPS) meets the combined power supply conditions including at least one of the following: the power demand of the load is greater than the power provided by the AC power supply, the state of charge (SOC) of the DC energy storage device is greater than the set SOC, the UPS operates within a set time period, and the estimated standby time of the DC energy storage device is greater than the set standby time.

[0127] The uninterruptible power supply meets the joint power supply conditions, including but not limited to: the state of charge of the DC energy storage device is greater than the set charge threshold, which is sufficient to provide the planned power; the health status value of the DC energy storage device is less than or greater than the set health threshold; the DC / AC inverter is working normally and there are no fault alarms; the system temperature is within the safe range; the load power demand is within the total system capacity; and the current time is within a preset time period.

[0128] It should be noted that the conditions for the above power supply status, as well as the conditions for combined power supply, can be set by the user according to their actual situation. For example... Figure 15 As shown, a settings page for combined power supply conditions is provided; as Figure 15 As shown, this page allows you to set the charge threshold, health threshold, reserved normal backup power time, the working time period of the combined power supply mode, the power supply percentage of the DC energy storage device, and the usage cycle of the above conditions, etc.

[0129] In one implementation, the AC power supply is in a normal operating state, and the uninterruptible power supply (UPS) meets the combined power supply conditions. A first control signal is generated and sent to the bypass switch, controlling the bypass switch to conduct and establishing an AC power supply connection to the load via the bypass switch. Almost simultaneously, a second control signal is generated and sent to the DC / AC inverter, controlling the DC / AC inverter to enter inversion mode. The controller issues a composite command to the DC / AC inverter, including: a status command to control the DC / AC inverter to enter inversion mode, and a power command to control the DC / AC inverter to output a first set active power P1. The DC / AC inverter immediately obtains electrical energy from the DC energy storage device and converts it into AC power with the same frequency and phase as the AC power supply. It then outputs an active power P1 to the load, sharing some of the load power that would otherwise be provided by the AC power supply.

[0130] The first set active power P1 is calculated from the actual active power required by the load and the pre-set power supply percentage.

[0131] In some embodiments, the first set power is determined based on a preset power supply percentage and the power requirements of the load.

[0132] The power demand of a load refers to the total active power required by the load at any given time. It can be a real-time variable that is continuously monitored by the controller through sensors. The preset power supply percentage is a proportion value pre-set by the user or system strategy (e.g., set to 60%), which limits the upper limit of the proportion of load power expected to be handled by DC energy storage devices in the combined power supply mode.

[0133] In one possible implementation, the load power conservation equation is P = Pgrid + P1, where P is the actual active power required by the load, Pgrid is the active power actually provided by the AC power supply, and P1 is the active power provided by the DC / AC inverter. The control objective is to make Pgrid less than a second set power P2. The controller controls the DC / AC inverter to output active power equal to the first set active power P1, such that Pgrid = P – P1. This limits the active power provided by the AC power supply to below the second set power P2.

[0134] During peak electricity consumption periods, the peak power drawn from the grid is proactively limited to avoid high demand charges and reduce grid pressure.

[0135] Based on the above embodiments, the present disclosure optimizes the uninterruptible power supply control method, such as... Figure 16 As shown, the optimized uninterruptible power supply control method includes steps S1602-S1608.

[0136] S1602, Detect the power supply status of the AC power supply.

[0137] S1604. If the AC power supply status is detected to meet the power supply requirements of the load, and the uninterruptible power supply meets the joint power supply conditions, a first control signal is sent to the bypass switch, and a second control signal is sent to the DC / AC inverter. The first control signal is used to control the bypass switch to be turned on, so that the AC power supply provides active power to the load through the bypass switch. The second control signal is used to control the DC / AC inverter to be in the inversion state, to obtain energy from the DC energy storage device, and to provide active power of a first set power to the load, so that the active power provided by the AC power supply to the load is less than the second set power.

[0138] S1606. If the AC power supply status is detected as not meeting the power supply requirements of the load, a third control signal is sent to the bypass switch and a fourth control signal is sent to the DC / AC inverter. The third control signal is used to control the bypass switch to turn off. The fourth control signal is used to control the DC / AC inverter to obtain energy from the DC energy storage device and provide all the required power to the load.

[0139] If the AC power supply is detected to be insufficient to meet the load's power requirements, and the uninterruptible power supply (UPS) meets the independent power supply conditions, the controller generates and sends a third control signal to the bypass switch, causing the bypass switch to turn off and immediately isolating the unstable or faulty AC power supply from the system to prevent damage to the load and equipment. Simultaneously, the controller generates and sends a fourth control signal to the DC / AC inverter, controlling it to supply power at full power, with the output power target value being the real-time total power demand of the load. The DC / AC inverter immediately switches from auxiliary power supply or standby mode to main power supply mode, reducing switching time.

[0140] S1608. If the AC power supply is found to meet the power supply requirements, but the uninterruptible power supply does not meet the joint power supply conditions, a first control signal is sent to the bypass switch and a fifth control signal is sent to the DC / AC inverter. The fifth control signal is used to control the DC / AC inverter to provide reactive power to the load.

[0141] If the AC power supply meets the power demand, but the uninterruptible power supply (UPS) does not meet the combined power supply conditions (e.g., the current time is not within a preset time period), the controller sends a first control signal to the bypass switch, controlling the bypass switch 110 to conduct, establishing a path from the mains power to the load. All active power required by the load will be provided by the AC power supply. The controller sends a fifth control signal to the DC / AC inverter 120. The DC / AC inverter 120 responds to the fifth control signal and enters reactive power compensation mode or static var generator (SVG) mode. It no longer attempts to obtain a large amount of energy from the battery to output active power, but instead generates and provides the reactive power required by the load by controlling the phase of its AC side output voltage.

[0142] Since the reactive current required by the load is provided by the local inverter, the grid only needs to provide the active current that is in phase with the voltage, so that the power factor of the entire system is compensated to be close to 1, thereby reducing line losses and improving energy utilization efficiency.

[0143] The following are embodiments of the controller disclosed herein, which can be used to execute the embodiments of the method disclosed herein. For details not disclosed in the embodiments of the controller disclosed herein, please refer to the embodiments of the method disclosed herein.

[0144] Figure 17 This is a block diagram illustrating a controller according to an exemplary embodiment. (Refer to...) Figure 17 The controller may include a status detection module 1710 and a signal transmission module 1720.

[0145] The status detection module 1710 is used to detect the power supply status of the AC power supply; the signal sending module 1720 is used to send a first control signal to the bypass switch and a second control signal to the DC / AC inverter if the detected power supply status of the AC power supply meets the power supply requirements of the load and the uninterruptible power supply meets the joint power supply conditions; the first control signal is used to control the bypass switch to be turned on so that the AC power supply provides active power to the load through the bypass switch; the second control signal is used to control the DC / AC inverter to be in the inversion state, to obtain energy from the DC energy storage device, and to provide active power to the load at a first set power, so that the active power provided by the AC power supply to the load is less than the second set power.

[0146] In some embodiments, the signal transmitting module 1720 is further configured to send a third control signal to the bypass switch and a fourth control signal to the DC / AC inverter if the power supply status of the AC power supply is detected as not meeting the power supply requirements of the load; the third control signal is used to control the bypass switch to turn off; the fourth control signal is used to control the DC / AC inverter to obtain energy from the DC energy storage device and provide all the required power to the load; if the AC power supply is detected as not meeting the power supply requirements and the uninterruptible power supply does not meet the joint power supply conditions, a first control signal is sent to the bypass switch and a fifth control signal is sent to the DC / AC inverter; the fifth control signal is used to control the DC / AC inverter to provide reactive power to the load.

[0147] In some embodiments, the uninterruptible power supply (UPS) meets the combined power supply conditions including at least one of the following: the power demand of the load is greater than the power provided by the AC power supply, the state of charge (SOC) of the DC energy storage device is greater than the set SOC, the UPS operates within a set time period, and the estimated standby time of the DC energy storage device is greater than the set standby time.

[0148] In some embodiments, the first set power is determined based on a preset bypass power percentage and the power requirements of the load.

[0149] Regarding the controller in the above embodiments, the specific manner in which each module performs its operations has been described in detail in the embodiments related to the method, and will not be elaborated upon here.

[0150] The following reference Figure 18 To describe an electronic device 1800 according to such an embodiment of the present disclosure. Figure 18 The electronic device 1800 shown is merely an example and should not impose any limitation on the functionality and scope of use of the embodiments disclosed herein.

[0151] like Figure 18As shown, the electronic device 1800 is presented in the form of a general-purpose computing device. The components of the electronic device 1800 may include, but are not limited to: at least one processing unit 1810, at least one storage unit 1820, a bus 1830 connecting different system components (including storage unit 1820 and processing unit 1810), and a display unit 1840.

[0152] The storage unit stores program code, which can be executed by the processing unit 1810 to perform the steps described in the "Exemplary Methods" section of this specification according to various exemplary embodiments of this disclosure. For example, the processing unit 1810 can perform actions such as... Figure 3 The steps shown. For example, electronic devices can achieve, for instance, the following steps. Figure 3 The steps shown.

[0153] Storage unit 1820 may include readable media in the form of volatile storage units, such as random access memory (RAM) 1821 and / or cache memory 1822, and may further include read-only memory (ROM) 1823.

[0154] Storage unit 1820 may also include a program / utility 1824 having a set (at least one) program module 1825, such program module 1825 including but not limited to: operating system, one or more application programs, other program modules and program data, each or some combination of these examples may include an implementation of a network environment.

[0155] Bus 1830 can represent one or more of several types of bus structures, including memory cell bus or memory cell controller, peripheral bus, graphics acceleration port, processing unit, or local bus using any of the various bus structures.

[0156] Electronic device 1800 can also communicate with one or more external devices 1870 (e.g., keyboard, pointing device, Bluetooth device, etc.), and with one or more devices that enable a user to interact with electronic device 1800, and / or with any device that enables electronic device 1800 to communicate with one or more other computing devices (e.g., router, modem, etc.). This communication can be performed via input / output (I / O) interface 1850. Furthermore, electronic device 1800 can also communicate with one or more networks (e.g., local area network (LAN), wide area network (WAN), and / or public networks, such as the Internet) via network adapter 1860. As shown, network adapter 1860 communicates with other modules of electronic device 1800 via bus 1830. It should be understood that, although not shown in the figures, other hardware and / or software modules can be used in conjunction with electronic device 1800, including but not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data backup storage systems.

[0157] From the above description of the embodiments, those skilled in the art will readily understand that the exemplary embodiments described herein can be implemented by software or by combining software with necessary hardware. Therefore, the technical solutions according to the embodiments of this disclosure can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (such as a CD-ROM, USB flash drive, external hard drive, etc.) or on a network, including several instructions to cause a computing device (such as a personal computer, server, terminal device, or network device, etc.) to execute the methods according to the embodiments of this disclosure.

[0158] In an exemplary embodiment, a computer-readable storage medium including instructions is also provided, such as a memory including instructions that can be executed by a processor of the device to perform the described method. Optionally, the computer-readable storage medium may be a ROM, random access memory (RAM), CD-ROM, magnetic tape, floppy disk, and optical data storage device, etc.

[0159] In an exemplary embodiment, a computer program product is also provided, including a computer program that, when executed by a processor, implements the methods described above.

[0160] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the following claims.

[0161] It should be understood that this disclosure is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this disclosure is limited only by the appended claims.

Claims

1. An uninterruptible power supply, characterized in that, include: A bypass switch, wherein a first terminal of the bypass switch is connected to an AC power source and a second terminal of the bypass switch is connected to a load, for conducting in response to a first control signal; The AC power supply provides active power to the load through the bypass switch; A DC / AC inverter, wherein a first terminal of the DC / AC inverter is connected to a DC energy storage device, and a second terminal of the DC / AC inverter is connected to the load, for responding to a second control signal, wherein the DC / AC inverter is in an inversion state, obtains energy from the DC energy storage device, and provides active power of a first set power to the load, such that the active power provided by the AC power supply to the load is less than a second set power.

2. The uninterruptible power supply according to claim 1, characterized in that, The bypass switch is also used to turn off in response to a third control signal; the DC / AC inverter is also used to obtain energy from the DC energy storage device and provide all the required power to the load in response to a fourth control signal when the bypass switch is turned off. The DC / AC inverter is also used to provide reactive power to the load in response to a fifth control signal when the bypass switch is turned on.

3. The uninterruptible power supply according to claim 1, characterized in that, Also includes: DC / DC / DC converter; The first terminal of the DC / DC converter is connected to the first terminal of the DC / AC inverter, and the second terminal of the DC / DC converter is connected to the DC energy storage device. The DC / DC converter is used to convert the output voltage of the DC energy storage device.

4. The uninterruptible power supply according to any one of claims 1-3, characterized in that, The DC / AC inverter is a three-phase clamped inverter, and the phase difference between any two phases of the PWM signal of the clamped inverter is the first angle; Each phase of the clamped inverter includes: a first transistor, a second transistor, a third transistor, a fourth transistor, a fifth transistor, a sixth transistor, a seventh transistor, an eighth transistor, a first inductor, a second inductor, and a first capacitor; The positive terminal of the DC energy storage device is connected to the first terminal of the first transistor and the first terminal of the second transistor, respectively. The second terminal of the first transistor is connected to the first terminal of the third transistor and the first terminal of the first inductor, respectively. The second terminal of the second transistor is connected to the first terminal of the fourth transistor and the first terminal of the second inductor, respectively. The negative terminal of the DC energy storage device is connected to the second terminal of the third transistor and the second terminal of the fourth transistor, respectively. The second terminal of the first inductor and the second terminal of the second inductor are connected to the load through a first connection point. The second terminal of the first inductor and the second terminal of the second inductor are connected to the neutral line through the first capacitor. The second terminal of the first transistor is connected to the neutral line through the fifth and sixth transistors, and the second terminal of the second transistor is connected to the neutral line through the seventh and eighth transistors.

5. The uninterruptible power supply according to claim 4, characterized in that, Also includes: Equalization circuit; The equalization circuit includes: a third inductor, a ninth transistor, and a tenth transistor; The positive terminal of the DC energy storage device is connected to the first terminal of the ninth transistor, and the negative terminal of the DC energy storage device is connected to the second terminal of the tenth transistor. The second terminal of the ninth transistor is connected to the first terminal of the tenth transistor and the first terminal of the seventh inductor, respectively, and the second terminal of the seventh inductor is connected to the neutral line.

6. The uninterruptible power supply according to claim 3, characterized in that, The DC / DC converter is a three-phase DC / DC converter, and the phase difference between any two phases of the PWM signal of the DC / DC converter is a first angle; Each phase of the DC / DC converter includes: an eleventh transistor, a twelfth transistor, a thirteenth transistor, a fourteenth transistor, a fourth inductor, and a fifth inductor; The positive terminal of the DC energy storage device is connected to the first terminal of the fourth inductor. The second terminal of the fourth inductor is connected to the first terminal of the eleventh transistor and the first terminal of the twelfth transistor. The second terminal of the eleventh transistor is connected to the first positive terminal of the DC / AC inverter. The second terminal of the twelfth transistor is connected to the neutral line. The negative terminal of the DC energy storage device is connected to the first terminal of the fifth inductor. The second terminal of the fifth inductor is connected to the first terminal of the thirteenth transistor and the first terminal of the fourteenth transistor. The second terminal of the thirteenth transistor is connected to the first negative terminal of the DC / AC inverter. The second terminal of the fourteenth transistor is connected to the neutral line.

7. The uninterruptible power supply according to any one of claims 1 or 2, characterized in that, Also includes: The controller is connected to the bypass switch and the DC / AC inverter respectively. When it detects that the AC power supply meets the power supply requirements and the combined power supply conditions are met, it sends a first control signal to the bypass switch and a second control signal to the DC / AC inverter. It is also used to send a first control signal to the bypass switch and a fifth control signal to the DC / AC inverter when it is detected that the AC power supply meets the power supply requirements and the uninterruptible power supply does not meet the joint power supply conditions; It is also used to send a third control signal to the bypass switch and a fourth control signal to the DC / AC inverter when it is detected that the AC power supply does not meet the power supply requirements.

8. An electric power system, characterized in that, The power system includes an uninterruptible power supply as described in any one of claims 1 to 7.

9. An uninterruptible power supply control method, characterized in that, The uninterruptible power supply includes: a bypass switch, the first terminal of which is connected to an AC power source and the second terminal of which is connected to a load; and a DC / AC inverter, the first terminal of which is connected to a DC energy storage device and the second terminal of which is connected to the load. The method includes: Detect the power supply status of the AC power source; If it is detected that the power supply status of the AC power supply meets the power supply requirements of the load, and the uninterruptible power supply meets the joint power supply conditions, a first control signal is sent to the bypass switch and a second control signal is sent to the DC / AC inverter. The first control signal is used to control the bypass switch to be turned on, so that the AC power supply provides active power to the load through the bypass switch; The second control signal is used to control the DC / AC inverter to be in an inverter state, to obtain energy from the DC energy storage device, and to provide active power of a first set power to the load, so that the active power provided by the AC power supply to the load is less than the second set power.

10. The uninterruptible power supply control method according to claim 9, characterized in that, Also includes: If it is detected that the power supply status of the AC power supply does not meet the power supply requirements of the load, a third control signal is sent to the bypass switch and a fourth control signal is sent to the DC / AC inverter; the third control signal is used to control the bypass switch to turn off. The fourth control signal is used to control the DC / AC inverter to obtain energy from the DC energy storage device and provide all the required power to the load; If the AC power supply is detected to meet the power supply requirements, and the uninterruptible power supply does not meet the joint power supply conditions, a first control signal is sent to the bypass switch, and a fifth control signal is sent to the DC / AC inverter; the fifth control signal is used to control the DC / AC inverter to provide reactive power to the load.

11. The uninterruptible power supply control method according to claim 9 or 10, characterized in that, The uninterruptible power supply (UPS) meets the joint power supply conditions including at least one of the following: the power demand of the load is greater than the power provided by the AC power supply; the state of charge (SOC) of the DC energy storage device is greater than the set SOC; the UPS operates within a set time period; and the estimated standby time of the DC energy storage device is greater than the set standby time.

12. The uninterruptible power supply control method according to claim 9, characterized in that, The first set power is determined based on the preset power supply percentage and the power requirements of the load.

13. A controller for an uninterruptible power supply, characterized in that, The uninterruptible power supply includes: a bypass switch, the first terminal of which is connected to an AC power source and the second terminal of which is connected to a load; a DC / AC inverter, the first terminal of which is connected to a DC energy storage device and the second terminal of which is connected to the load; and a controller, which is connected to the bypass switch and the DC / AC inverter respectively. The controller includes: A status detection module is used to detect the power supply status of the AC power supply; The signal transmitting module is used to send a first control signal to the bypass switch and a second control signal to the DC / AC inverter if it is detected that the power supply status of the AC power supply meets the power supply requirements of the load and the uninterruptible power supply meets the joint power supply conditions. The first control signal is used to control the bypass switch to be turned on, so that the AC power supply provides active power to the load through the bypass switch; The second control signal is used to control the DC / AC inverter to be in an inverter state, to obtain energy from the DC energy storage device, and to provide active power of a first set power to the load, so that the active power provided by the AC power supply to the load is less than the second set power.

14. An electronic device, characterized in that, include: processor; Memory used to store the processor's executable instructions; The processor is configured to execute the executable instructions to implement the uninterruptible power supply control method as described in any one of claims 9 to 12.

15. A computer-readable storage medium, wherein instructions in the computer-readable storage medium, when executed by a processor of an electronic device, enable the electronic device to perform the uninterruptible power supply control method as described in any one of claims 9 to 12.

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