A combined power supply circuit

Abstract

The embodiment of the application discloses a kind of joint power supply circuit, for power supply technical field.The joint power supply circuit includes: DC power supply branch and multiple power supply branches;One end of power supply branch includes: DC control module and AC control module, and the DC control module of power supply branch is connected with battery;The AC control module of power supply branch is connected with AC power supply module;Wherein, AC power supply module includes: mains and generator, when mains is in abnormal state, through DC control module, sequentially reduce the power supply branch of the power supply of battery, and through AC control module, sequentially increase the power supply branch of the AC power supply of generator, by sequentially increasing the power supply branch of AC power supply, avoid cutting into load at one time, effectively avoid to cause relatively big dynamic problem to generator.

Description

Technical Field

[0001] This application relates to the field of power supply technology, and in particular to a combined power supply circuit. Background Technology

[0002] An uninterruptible power supply (UPS) provides uninterrupted power to a load. Existing UPS systems combine AC and DC power supplies. The DC power supply primarily uses batteries, while the AC power supply consists of mains power and a generator, which can be a fuel-powered or gas-powered generator. During AC power supply, mains power is used preferentially; if the mains power fails, the system switches to generator power.

[0003] When switching from mains power to generator power, the generator's power supply may fluctuate under unstable load conditions, potentially causing power outages. In such cases, battery power supplementation is necessary until the generator's power supply stabilizes. Generator startup typically involves starting under load, requiring a significant current. Without supplementary power, a larger capacity generator would be necessary; furthermore, switching to a single load during supplementary power supply can cause substantial dynamic problems for the generator. Summary of the Invention

[0004] This application provides a combined power supply circuit that effectively avoids causing significant dynamic problems to the generator.

[0005] This application provides a combined power supply circuit, including: a DC power supply branch and multiple power supply branches;

[0006] One end of the power supply branch includes a DC control module and an AC control module. The DC control module of the power supply branch is connected to the battery and is used to turn the battery on or off. The AC control module of the power supply branch is connected to the AC power supply module and is used to turn the AC power supply module on or off. The AC power supply module includes a mains power supply and a generator. When the mains power supply is in an abnormal state, the power supply switches from the mains power supply to the generator for AC power supply, and the AC control module adds power supply branches that use the generator for AC power supply one by one.

[0007] One end of the DC power supply branch includes a DC control module, which is connected to the battery.

[0008] The other end of each of the multiple power supply branches and the other end of the DC power supply branch are connected to the busbar.

[0009] Furthermore, the AC control module includes: a first rectifier and a second rectifier;

[0010] The positive terminal of the first rectifier is connected to the negative terminal of the second rectifier and the preset connection of the AC power supply module; the negative terminal of the first rectifier is connected to the positive terminal of the power supply branch, and the positive terminal of the second rectifier is connected to the negative terminal of the power supply branch.

[0011] The first rectifier and the second rectifier also include a conduction control terminal, through which the first rectifier and the second rectifier are turned on or off.

[0012] Furthermore, the power supply branch includes: a first inductor, a second inductor, a first switching transistor, a second switching transistor, a first diode, a second diode, a first capacitor, and a second capacitor;

[0013] One end of the first inductor is connected to the positive terminal of the power supply branch, the other end of the first inductor is connected to one end of the first switching transistor and the anode of the first diode, and the cathode of the first diode is connected to one end of the first capacitor and the positive busbar of the busbar.

[0014] The other end of the first switching transistor is connected to one end of the second switching transistor, the other end of the first capacitor, one end of the second capacitor, and the neutral wire of the busbar.

[0015] One end of the second inductor is connected to the negative terminal of the power supply branch, the other end of the second inductor is connected to the other end of the second switching transistor and the cathode of the second diode, and the anode of the second diode is connected to the other end of the second capacitor and the negative busbar of the busbar.

[0016] Furthermore, the DC power supply branch includes: a third inductor, a third switching transistor, a fourth switching transistor, a fifth switching transistor, a sixth switching transistor, a third capacitor, and a fourth capacitor;

[0017] One end of the third inductor is connected to the positive terminal of the DC power supply branch, and the other end of the third inductor is connected to one end of the third switch and one end of the fifth switch. The other end of the fifth switch is connected to one end of the third capacitor and the positive busbar of the bus.

[0018] The other end of the third switch is connected to one end of the fourth switch, the other end of the third capacitor, one end of the fourth capacitor, and the neutral wire of the busbar.

[0019] The other end of the fourth switch is connected to the negative terminal of the DC power supply branch and one end of the sixth switch, and the other end of the sixth switch is connected to the other end of the fourth capacitor and the negative bus of the bus.

[0020] Furthermore, it also includes: a status detection module;

[0021] The status detection module is connected to the generator and is used to collect the generator's operating parameters and determine the generator's operating status based on the operating parameters.

[0022] When the mains power is in an abnormal state, the status detection module determines whether the generator's operating status is stable;

[0023] If so, the AC control module will sequentially connect the generator to each of the multiple power supply branches, and the status detection module will determine whether the generator’s operating status is stable each time the generator is connected.

[0024] If not, the generator is controlled to remain in the previous conduction state via the AC control module.

[0025] Furthermore, the operating parameters of the generator include: voltage envelope and current envelope;

[0026] The state detection module is specifically used to determine whether the voltage difference of the voltage envelope is greater than a preset voltage threshold within a preset duration, and / or to determine whether the current difference of the current envelope is greater than a preset current threshold within a preset duration, thereby determining whether the operating state of the generator is stable.

[0027] Furthermore, the DC power supply branch includes: a charging and discharging control unit;

[0028] When multiple power supply branches are connected to the generator and the combined power supply circuit is in a stable state, the charging and discharging control unit controls the DC power supply branches to charge the battery.

[0029] Furthermore, when the combined power supply circuit is in battery mode, the DC control module is used to conduct the battery corresponding to the preset branch from the DC power supply branch and multiple power supply branches based on the load of the bus connection, so that the preset branch operates at a preset load rate.

[0030] Furthermore, when the combined power supply circuit is in the mains power state, the AC control module is used to conduct the mains power corresponding to the preset branch from multiple power supply branches when the load connected to the bus is less than the preset load threshold, so that the preset branch works at the preset load rate, and to use the target branch that is not connected to the mains power from multiple power supply branches, as well as the DC power supply branch, to charge the battery through multiple channels.

[0031] Furthermore, the target branch includes: a first inductor, a second inductor, a first switching transistor, a second switching transistor, a third switching transistor, a fourth switching transistor, a first capacitor, and a second capacitor;

[0032] One end of the first inductor is connected to the positive terminal of the power supply branch, and the other end of the first inductor is connected to one end of the first switching transistor and one end of the third switching transistor. The other end of the third switching transistor is connected to one end of the first capacitor and the positive busbar of the busbar.

[0033] The other end of the first switching transistor is connected to one end of the second switching transistor, the other end of the first capacitor, one end of the second capacitor, and the neutral wire of the busbar.

[0034] One end of the second inductor is connected to the negative terminal of the power supply branch, and the other end of the second inductor is connected to the other end of the second switching transistor and one end of the fourth switching transistor. The other end of the fourth switching transistor is connected to the other end of the second capacitor and the negative busbar of the busbar.

[0035] As can be seen from the above technical solutions, the embodiments of this application have the following advantages:

[0036] The combined power supply circuit of this application embodiment includes: a DC power supply branch and multiple power supply branches; one end of each power supply branch includes: a DC control module and an AC control module, the DC control module of the power supply branch being connected to a battery; the AC control module of the power supply branch being connected to the AC power supply module; wherein, the AC power supply module includes: mains power and a generator. When the mains power is in an abnormal state, the DC control module gradually reduces the power supply branches that provide supplementary power through the battery, and the AC control module gradually increases the power supply branches that provide AC power through the generator. By increasing the AC power supply branches sequentially, the load is not switched on all at once, effectively avoiding significant dynamic problems to the generator. Attached Figure Description

[0037] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings.

[0038] Figure 1 This is a block diagram of a conventional power supply circuit disclosed in an embodiment of this application;

[0039] Figure 2 This is a block diagram of a combined power supply circuit disclosed in an embodiment of this application;

[0040] Figure 3 This is a circuit diagram of a combined power supply circuit disclosed in an embodiment of this application. Detailed Implementation

[0041] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0042] In the description of the embodiments of this application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0043] In the description of the embodiments of this application, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application based on the specific circumstances.

[0044] Existing power supply circuits such as Figure 1 As shown, the DC power supply (DC power supply) mainly uses batteries, while the AC power supply (AC power supply) consists of mains power and a generator. During AC power supply, mains power is used first; if the mains power fails, it switches to generator power. L1, L2, and L3 are the three-phase AC power inputs. When the rectifier module operates in AC power supply mode, it supplies power to the bus via both AC and DC power, and then outputs it to the load after passing through the inverter. This power supply circuit is a three-and-a-half-way multiplexed circuit. The DC power supply (DC power to the negative bus circuit) is a bidirectional circuit, allowing charging of the battery during AC power supply.

[0045] When switching from mains power to generator power, battery power is required to compensate. However, the battery's power compensation is limited. When the load requires a large amount of power, a larger capacity generator is needed to meet the load's power demand. This necessitates a significant investment in a large-capacity generator, increasing the cost of combined power supply. Therefore, this application provides a combined power supply circuit that eliminates the need for a large-capacity generator, reducing the overall cost of combined power supply. Figure 2 As shown, the details are as follows:

[0046] The combined power supply circuit of this application embodiment includes a DC power supply branch and multiple power supply branches (power supply branch 1, power supply branch 2, and power supply branch 3); wherein, one end of the power supply branch includes a DC control module and an AC control module, the DC control module of the power supply branch is connected to the battery and is used to turn the battery on or off, the battery is used to provide DC power, that is, the DC control module is used to turn the DC power supply on or off; the DC control module can be a unidirectional switching transistor or a MOSFET, which is not limited here.

[0047] The AC control module of the power supply branch is connected to the AC power supply module and is used to turn the AC power supply module on or off. The AC power supply module includes mains power and a generator. Normally, the AC power supply module is powered by the mains power. When the mains power is in an abnormal state, the power supply switches from the mains power to the generator. An abnormal mains power state can be a mains power outage or a mains power fluctuation frequency exceeding a preset frequency threshold; the specifics are not limited here. It is understood that each power supply branch only operates in either DC or AC power supply mode. Specifically, in each power supply branch, when the DC control module is on the battery, the AC control module of that branch disconnects the AC power supply module, allowing the branch to operate with DC power; when the AC control module is on the AC power supply module, the DC control module disconnects the battery, allowing the branch to operate with AC power. The rated AC voltage of the mains power can be 220Vac, the rated DC voltage of the battery can be 192Vdc, and the load power can be 10kW. The generator can be a fuel-powered generator or a gas-powered generator. The fuel-powered generator can be a diesel generator, a gasoline generator, a heavy oil generator, etc., and the specific type is not limited here.

[0048] Understandably, these multiple power supply branches are used to provide DC or AC power to the busbar. When the mains power is abnormal, the DC control module gradually reduces the power supply branches that rely on batteries for supplementary power, while the AC control module gradually adds power supply branches that rely on generators for AC power. In other words, when the mains power is abnormal, the batteries first provide DC power to most or all of the power supply branches for supplementary power. Then, the AC control module gradually adds power supply branches to the generator. When a preset power supply branch connects to the generator, the DC control module of that preset branch disconnects the battery connected to that preset branch. By gradually adding the load to the generator, a one-time load switching can be avoided.

[0049] One end of the DC power supply branch includes a DC control module, which is connected to the battery and is used to turn the DC power supply on or off. The other ends of the multiple power supply branches and the other end of the DC power supply branch are all connected to a bus. This bus is connected to the load, providing it with power. Therefore, this combined power supply circuit is a fully multiplexed circuit, further improving the utilization rate of power devices.

[0050] It is understandable that when the combined power supply circuit is in mains power mode, the power supply for each path is 1 / 3 * Pout, where Pout is the output power of the circuit. When the combined power supply circuit is in battery power mode, all power supply branches and the DC control modules of the DC power supply branches are connected to the battery. When there are multiple power supply branches, there are 3 power supply branches. The input power of the battery in each power supply branch is 1 / 4 of the output power of the combined power supply circuit, and the input power of the battery in the DC power supply circuit is also 1 / 4 of the output power of the combined power supply circuit. That is, in battery power mode, the power supply for each path is 1 / 4 * Pout. The current of each device is basically the same in mains power mode and battery power mode, resulting in high utilization. When the combined power supply circuit is in mains power mode, the AC control modules of all power supply branches are connected to the mains power, and the DC control modules of the DC power supply branches are disconnected from the battery. When the mains power in the AC power supply module is in an abnormal state, the AC control modules of some power supply branches in the combined power supply circuit are connected to the generator, and the DC control modules of other power supply branches are connected to the battery, so that the output power of the combined power supply circuit does not need to be entirely provided by the generator, thus reducing the generator capacity.

[0051] As can be seen, the combined power supply circuit of this application embodiment includes: a DC power supply branch and multiple power supply branches; one end of the power supply branch includes: a DC control module and an AC control module, the DC control module of the power supply branch is connected to the battery; the AC control module of the power supply branch is connected to the AC power supply module; wherein, the AC power supply module includes: mains power and a generator, when the mains power is in an abnormal state, the DC control module reduces the power supply branches that provide supplementary power through the battery one by one, and the AC control module adds the power supply branches that provide AC power through the generator one by one, by adding the AC power supply branches in sequence, avoiding a one-time load cut-off, effectively avoiding causing relatively large dynamic problems to the generator.

[0052] In one feasible approach, the battery is reused to provide DC power to multiple power supply branches, reducing the AC power supply from the generator to the power supply branches. This allows the combined power supply circuit to support smaller capacity generators without the need for large-capacity generators, thus reducing the cost of combined power supply.

[0053] Furthermore, the combined power supply process will be described in detail below through the circuit structure of the combined power supply circuit. The circuit structure of the combined power supply circuit is as follows: Figure 3 As shown, there are three power supply branches: branch 1, branch 2, and branch 3; the DC power supply branch is branch 4; L represents the preset phase AC power in the three-phase AC power supply; S represents the DC control module; BAT+ is the positive terminal of the battery; and BAT- is the negative terminal of the battery. In this case, when the combined power supply circuit is in battery mode, it can reuse the three power supply branches from the AC power mode. Therefore, in battery mode, the combined power supply circuit only needs to select components based on 1 / 4 of the rated output power, effectively improving component reuse rate and reducing circuit size.

[0054] The AC control modules (S1, S2, and S3) of the power supply branch include a first rectifier and a second rectifier, which convert the input AC power into DC power. The first and second rectifiers can be silicon controlled rectifiers (SCRs). The positive terminal of the first rectifier is connected to the negative terminal of the second rectifier and a preset connection of the AC power supply module. The negative terminal of the first rectifier is connected to the positive terminal of the power supply branch, and the positive terminal of the second rectifier is connected to the negative terminal of the power supply branch. The positive terminal of the power supply branch is the DC positive terminal, and the negative terminal is the DC negative terminal. The first and second rectifiers also include a conduction control terminal, which turns the first and second rectifiers on or off. For example, with a silicon controlled rectifier (SCR), applying a positive voltage between the gate and cathode turns the anode-gate connection on. The SCR begins to conduct when forward biased, i.e., the cathode is under negative voltage and the anode is under positive voltage. The first and second rectifiers can be used to turn on or off the AC power input to the AC power supply module and to rectify the AC power.

[0055] Furthermore, this power supply branch includes: a first inductor, a second inductor, a first switching transistor, a second switching transistor, a first diode, a second diode, a first capacitor, and a second capacitor; the first switching transistor and the second switching transistor can be MOSFETs or transistors connected in parallel with diodes, and the specifics are not limited here. For example, branch 1 includes: a first inductor L 1-1 Second inductor L 1-2 First switching transistor Q 1-1 Second switching transistor Q 1-2 First and second stage pipes D 1-1 Secondary tube D 1-2 First capacitor C 1-1 and the second capacitor C 1-2 First inductor L 1-1 One end of the first inductor L is connected to the positive terminal of the power supply branch. 1-1 The other end is connected to the first switching transistor Q 1-1 One end and the first and second diodes D1-1 Anode connection, first and second diodes D 1-1 The cathode and the first capacitor C 1-1 One end of the busbar and the positive busbar +BUS connection; the first switch Q 1-1 The other end is connected to the second switch Q. 1-2 One end, the first capacitor C 1-1 The other end, the second capacitor C 1-2 One end is connected to the neutral line N of the busbar; the second inductor L 1-2 One end of the second inductor L is connected to the negative terminal of the power supply branch. 1-2 The other end is connected to the second switch Q. 1-2 The other end and the second diode D 1-2 Cathode connection, second diode D 1-2 The anode and the second capacitor C 1-2 The other end is connected to the negative busbar - BUS. Through the series connection of the first switch and the second switch, signal distortion in the power supply branch can be effectively avoided. It is understood that the circuit structures of branch 2 and branch 3 are similar, and will not be elaborated upon here.

[0056] Furthermore, the DC power supply branch (branch 4) includes: a third inductor L3, a third switch Q3, a fourth switch Q4, a fifth switch Q5, a sixth switch Q6, a third capacitor C3, and a fourth capacitor C4; one end of the third inductor L3 is connected to the positive terminal of the DC power supply branch, and the other end of the third inductor L3 is connected to one end of the third switch Q3 and one end of the fifth switch Q5; the other end of the fifth switch Q5 is connected to one end of the third capacitor C3 and the positive busbar +BUS of the busbar; the other end of the third switch Q3 is connected to one end of the fourth switch Q4, the other end of the third capacitor C3, one end of the fourth capacitor C4, and the neutral line N of the busbar; the other end of the fourth switch Q4 is connected to the negative terminal of the DC power supply branch and one end of the sixth switch Q6; the other end of the sixth switch Q6 is connected to the other end of the fourth capacitor C4 and the negative busbar -BUS of the busbar. It is understandable that the fifth switch Q5 and the sixth switch Q6 have bidirectional functions, enabling the battery connected to the DC power supply branch to charge and discharge. During battery discharge, the third switch Q3 and the fourth switch Q4 are controlled by the duty cycle, while the fifth switch Q5 and the sixth switch Q6 are normally open, and the battery discharges to the bus. During battery charging, the third switch Q3 and the fourth switch Q4 are normally open, while the fifth switch Q5 and the sixth switch Q6 are controlled by the duty cycle, and the battery is charged through the bus.

[0057] Furthermore, when the mains power is in an abnormal state and switching to the generator for AC power supply is required, the generator and battery power supply can be time-sharingly controlled across each branch, improving the power flexibility of the combined power supply. The combined power supply circuit also includes a status detection module. This module is connected to the generator and is used to collect the generator's operating parameters and determine its operating status based on these parameters. The generator's operating parameters can be current, voltage, or frequency parameters, and are not specifically limited here. Preferably, the generator's operating parameters include a voltage envelope and a current envelope; the envelope refers to the waveform output after the signal passes through a detector, i.e., the outer edge of the signal. When the mains power is in an abnormal state, the status detection module is specifically used to determine whether the voltage difference of the voltage envelope is greater than a preset voltage threshold within a preset duration; and / or, to determine whether the current difference of the current envelope is greater than a preset current threshold within a preset duration, thereby determining whether the generator's operating status is stable.

[0058] The preset voltage threshold can be 10% or 15% of the generator input detector voltage Uin, which is not specifically limited here; the preset duration can be 200ms or 300ms, which is not specifically limited here. Preferably, the preset duration can be adjusted based on the power frequency period of the detector. The preset current threshold can be 10% or 15% of the generator input detector current Iin, which is not specifically limited here. If the voltage difference of the voltage envelope is greater than the preset voltage threshold within the preset duration, and / or the current difference of the current envelope is greater than the preset current threshold within the preset duration, then the generator's operating state is determined to be unstable; otherwise, the generator's operating state is determined to be stable.

[0059] If the generator's operating status is stable, the AC control module sequentially activates the generator on multiple power supply branches. Each time the generator is activated, the status detection module determines whether its operating status is stable. If the generator's operating status is unstable, the AC control module controls the generator to return to the previous activation state. In other words, the time-sharing process of generator and battery power supply is as follows: when it is determined that switching to AC power supply from the generator is necessary, the generator's output power continuously increases. The AC control module controls one power supply branch to provide AC power to the generator and determines whether the generator's operating status is stable. If stable, it controls the next power supply branch to provide AC power to the generator; if unstable, it reduces the number of power supply branches providing AC power to the generator by one.

[0060] As shown in Table 1 below, for multiple power supply branches (branch 1, branch 2, and branch 3) and a DC power supply branch (branch 4), when the mains power is in an abnormal state, the process of switching to the generator for AC power supply is as follows: Step 1: Branches 1-4 are all powered by batteries. At this time, the generator has just started, and the generator's output power is relatively small. The output power Pout of the bus is provided by the battery. Step 2: Branch 1 is powered by the generator, and branches 2-4 are all powered by batteries. 25% of the output power of the bus is provided by the generator, and 75% is provided by the battery. At this time, it is possible to... To determine if the generator's operating status is stable, if yes, proceed to step 3; otherwise, maintain the power supply mode of step 1. Step 3: Branches 1-2 are powered by the generator, and branches 3-4 are powered by the battery. 50% of the bus's output power is provided by the generator and 50% by the battery. At this point, it can be determined again whether the generator's operating status is stable. If stable, proceed to step 4. Step 4: Branches 1-3 are powered by the generator, and branch 4 is powered by the battery. 75% of the bus's output power is provided by the generator and 25% by the battery.

[0061] The DC power supply branch includes a charge / discharge control unit (i.e., the fifth and sixth switching transistors). When multiple power supply branches are all powered on by the generator and the combined power supply circuit is in a stable state, the charge / discharge control unit controls the DC power supply branch to charge the battery. Specifically, in step 5: branches 1-3 are powered by the generator, branch 4 charges the battery, and the output power of the bus is provided by the generator. 25% of the output power is used to charge the battery to maintain its backup capacity.

[0062] Table 1

[0063]

[0064] It is understood that the combined power supply circuit in this embodiment is compatible with single and three-phase power. When it has four branches, it can be compatible with a minimum generator capacity of 0.25 * Pout. Furthermore, the more branches there are, the smaller the backward-compatible generator capacity, resulting in better generator adaptability. It is suitable not only for combined power supply of large-capacity generators but also for small-capacity generators. Because generator power is supplied in stages through multiple branches, the power supply is smooth and flexible, avoiding generator power supply failures, ensuring high reliability and good flexibility in combined power supply. In one feasible implementation, it is not only applicable to four branches but also to various parallel power supply forms. It is understood that the three power supply branches and one DC power supply branch in this embodiment are for three-phase AC power. The number of power supply branches can be expanded based on the power, cost, and size of the product used in the combined power supply circuit. Without considering the power, cost, and size of the product, it can be infinitely backward compatible with generator capacities. However, under the premise of meeting the requirements of volume, power or cost, a comprehensive consideration is required. That is, the optimal number of power supply branches should be selected based on the power, cost and volume of the product. The more power supply branches there are, the smaller the capacity of the generator that can be compatible. The optimal number of power supply branches can determine the generator with the smallest backward compatibility.

[0065] Furthermore, when the combined power supply circuit is in battery mode, the number of electromagnetic power supply branches can be adjusted to improve battery mode efficiency. In battery mode, branches 1-4 are all powered by batteries via the DC control module, and branches 1-4 are connected in parallel. After the battery mode operation stabilizes, the load on the bus connection can be calculated. The battery discharge curve can be measured to determine battery stability. The DC control module is used to activate the batteries corresponding to preset branches from the DC power supply branches and multiple power supply branches based on the load on the bus connection, so that the preset branches operate at a preset load rate. This preset load rate can be 50%-75% of the branch's full load (0.25*Pout) to improve battery mode efficiency. For example, when the load is 10kW, and the full load of each branch is also 10kW, only the batteries of two branches can be activated, and these two branches operate at 50% of full load.

[0066] Furthermore, when the combined power supply circuit is in mains mode, branches 1-3 are powered by mains, while branch 4 is not powered. Due to losses generated by the rectifiers in branches 1-3, the number of branches participating in the power supply can be controlled by the load, thereby improving mains efficiency. That is, the number of branches participating in the power supply is controlled from branches 1-3 based on the load, so that the branches operate at a preset load rate, improving mains efficiency. It is understandable that in the case of three-phase mains power supply, if the branches participating in the power supply are not three-phase, it can easily lead to power imbalance. If the load and generator allow a wide degree of imbalance, one or two phase power supply branches can be selectively shut down. When the load is light and the mains power supply is single-phase, the number of branches participating in the power supply is reduced to avoid power imbalance caused by a single phase not operating.

[0067] Furthermore, when the combined power supply circuit is in mains power mode, the DC power supply branch is used to charge the battery. At this time, the idle power supply branch can be used to further improve the battery charging efficiency. When the combined power supply circuit is in mains power mode, the AC control module is used to conduct mains power from multiple power supply branches to the corresponding preset branch when the load connected to the bus is less than a preset load threshold, that is, when the load connected in mains power mode is light load, so that the preset branch works at a preset load rate. After the mains power system stabilizes, the target branch that is not connected to mains power from multiple power supply branches, as well as the DC power supply branch, can be used to charge the battery through multiple channels. For example, when the load corresponding to mains power mode is light load, and branch 3 is not connected to mains power and is idle, branch 3 and the DC power supply branch can be used simultaneously to charge the battery, speeding up the charging efficiency and improving the utilization rate of the device.

[0068] The circuit structure of the target branch (branch 3) that is not connected to the mains power includes: a first inductor L3-1, a second inductor L3-2, a first switch Q3-1, a second switch Q3-2, a third switch Q3-3, a fourth switch Q3-4, a first capacitor C3-1, and a second capacitor C3-2; one end of the first inductor L3-1 is connected to the positive terminal of the power supply branch, the other end of the first inductor L3-1 is connected to one end of the first switch Q3-1 and one end of the third switch Q3-3, and the other end of the third switch Q3-3 is connected to the first capacitor C3-4. -1 is connected to one end of the busbar and the positive busbar +BUS; the other end of the first switch Q3-1 is connected to one end of the second switch Q3-2, the other end of the first capacitor C3-1, one end of the second capacitor C3-2, and the neutral line N of the busbar; one end of the second inductor L3-2 is connected to the negative terminal of the power supply branch, the other end of the second inductor L3-2 is connected to the other end of the second switch Q3-2 and one end of the fourth switch Q3-4, and the other end of the fourth switch Q3-4 is connected to the other end of the second capacitor C3-2 and the negative busbar +BUS of the busbar.

[0069] As can be seen, in branch 3, the diode is replaced with a switching transistor, and the third and fourth switching transistors in branch 3 are 650V transistors with a switching frequency of 36kHz. They have bidirectional function, that is, branch 3 and branch 4 form two BOOSTs (switching DC boost circuits). In the mains power state, the two BOOSTs charge the battery, which improves the battery charging efficiency.

[0070] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0071] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0072] In the embodiments provided in this application, it should be understood that the disclosed devices / controllers and methods can be implemented in other ways. For example, the device / controller embodiments described above are merely illustrative. For instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0073] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0074] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0075] If integrated modules / units are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the methods of the above embodiments can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the control methods of the various energy storage UPS embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc.

[0076] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A combined power supply circuit, characterized in that, include: DC power supply branch, and multiple power supply branches; One end of the power supply branch includes a DC control module and an AC control module. The DC control module of the power supply branch is connected to the battery and is used to turn the battery on or off. When the combined power supply circuit is in battery mode, the DC control module is used to turn on the battery corresponding to the preset branch from the DC power supply branch and multiple power supply branches based on the load of the bus connection, so that the preset branch works at a preset load rate. The AC control module of the power supply branch is connected to the AC power supply module and is used to turn the AC power supply module on or off. The AC power supply module includes a mains power supply and a generator. When the mains power supply is in an abnormal state, the power supply is switched from the mains power supply to the generator for AC power supply. First, the battery provides DC power supply to most or all of the power supply branches for supplementary power supply. Then, the AC control module adds power supply branches that are supplied AC power through the generator one by one. When a power supply branch is supplied AC power through the generator, the DC control module of the power supply branch disconnects the battery connected to the power supply branch. One end of the DC power supply branch includes a DC control module, which is connected to the battery. The other end of each of the multiple power supply branches and the other end of the DC power supply branch are connected to the busbar.

2. The combined power supply circuit according to claim 1, characterized in that, The AC control module includes: a first rectifier and a second rectifier; The positive terminal of the first rectifier is connected to the negative terminal of the second rectifier and the preset connection of the AC power supply module; the negative terminal of the first rectifier is connected to the positive terminal of the power supply branch, and the positive terminal of the second rectifier is connected to the negative terminal of the power supply branch. The first rectifier and the second rectifier also include a conduction control terminal, through which the first rectifier and the second rectifier are turned on or off.

3. The combined power supply circuit according to claim 1, characterized in that, The power supply branch includes: a first inductor, a second inductor, a first switching transistor, a second switching transistor, a first diode, a second diode, a first capacitor, and a second capacitor; One end of the first inductor is connected to the positive terminal of the power supply branch, the other end of the first inductor is connected to one end of the first switching transistor and the anode of the first diode, and the cathode of the first diode is connected to one end of the first capacitor and the positive busbar of the busbar. The other end of the first switching transistor is connected to one end of the second switching transistor, the other end of the first capacitor, one end of the second capacitor, and the neutral wire of the busbar. One end of the second inductor is connected to the negative terminal of the power supply branch, the other end of the second inductor is connected to the other end of the second switching transistor and the cathode of the second diode, and the anode of the second diode is connected to the other end of the second capacitor and the negative busbar of the busbar.

4. The combined power supply circuit according to claim 1, characterized in that, The DC power supply branch includes: a third inductor, a third switch, a fourth switch, a fifth switch, a sixth switch, a third capacitor, and a fourth capacitor; One end of the third inductor is connected to the positive terminal of the DC power supply branch, and the other end of the third inductor is connected to one end of the third switch and one end of the fifth switch. The other end of the fifth switch is connected to one end of the third capacitor and the positive busbar of the bus. The other end of the third switch is connected to one end of the fourth switch, the other end of the third capacitor, one end of the fourth capacitor, and the neutral wire of the busbar. The other end of the fourth switch is connected to the negative terminal of the DC power supply branch and one end of the sixth switch, and the other end of the sixth switch is connected to the other end of the fourth capacitor and the negative bus of the bus.

5. The combined power supply circuit according to claim 1, characterized in that, It also includes: a status detection module; The status detection module is connected to the generator and is used to collect the generator's operating parameters and determine the generator's operating status based on the operating parameters. When the mains power is in an abnormal state, the status detection module determines whether the generator's operating status is stable; If so, the AC control module will sequentially connect the generator to each of the multiple power supply branches, and the status detection module will determine whether the generator’s operating status is stable each time the generator is connected. If not, the generator is controlled to remain in the previous conduction state via the AC control module.

6. The combined power supply circuit according to claim 5, characterized in that, The operating parameters of the generator include: voltage envelope and current envelope; The state detection module is specifically used to determine whether the voltage difference of the voltage envelope is greater than a preset voltage threshold within a preset duration, and / or to determine whether the current difference of the current envelope is greater than a preset current threshold within a preset duration, thereby determining whether the operating state of the generator is stable.

7. The combined power supply circuit according to claim 5, characterized in that, The DC power supply branch includes: a charging and discharging control unit; When multiple power supply branches are connected to the generator and the combined power supply circuit is in a stable state, the charging and discharging control unit controls the DC power supply branches to charge the battery.

8. The combined power supply circuit according to claim 1, characterized in that, When the combined power supply circuit is in the mains power state, the AC control module is used to conduct the mains power corresponding to the preset branch from multiple power supply branches when the load connected to the bus is less than the preset load threshold, so that the preset branch works at the preset load rate, and use the target branch of the multiple power supply branches that is not connected to the mains power, as well as the DC power supply branch, to charge the battery through multiple channels.

9. The combined power supply circuit according to claim 8, characterized in that, The target branch includes: a first inductor, a second inductor, a first switching transistor, a second switching transistor, a third switching transistor, a fourth switching transistor, a first capacitor, and a second capacitor; One end of the first inductor is connected to the positive terminal of the power supply branch, and the other end of the first inductor is connected to one end of the first switching transistor and one end of the third switching transistor. The other end of the third switching transistor is connected to one end of the first capacitor and the positive busbar of the busbar. The other end of the first switching transistor is connected to one end of the second switching transistor, the other end of the first capacitor, one end of the second capacitor, and the neutral wire of the busbar. One end of the second inductor is connected to the negative terminal of the power supply branch, and the other end of the second inductor is connected to the other end of the second switching transistor and one end of the fourth switching transistor. The other end of the fourth switching transistor is connected to the other end of the second capacitor and the negative busbar of the busbar.

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