CN115864621A

CN115864621A - Uninterrupted power source UPS and power supply system

Info

Publication number: CN115864621A
Application number: CN202111117254.8A
Authority: CN
Inventors: 胡智伦
Original assignee: Huawei Digital Power Technologies Co Ltd
Current assignee: Huawei Digital Power Technologies Co Ltd
Priority date: 2021-09-23
Filing date: 2021-09-23
Publication date: 2023-03-28

Abstract

The application provides an uninterrupted power source UPS and power supply system for when satisfying the demand of load to the electric energy, reduce UPS's cost, promote UPS's efficiency. The UPS comprises a Power Factor Correction (PFC) circuit, an inverter circuit, a battery pack, a positive bus and a negative bus; the input end of the PFC circuit is connected with the battery pack, the output end of the PFC circuit is respectively connected with the positive bus and the negative bus, and the PFC circuit is used for receiving the voltage output by the battery pack through the input end of the PFC circuit, converting the voltage output by the battery pack into a first voltage and outputting the first voltage to one or both of the positive bus and the negative bus; the input end of the inverter circuit is connected with the positive bus and the negative bus, and the inverter circuit is used for converting the voltages on the positive bus and the negative bus into a second voltage and outputting the second voltage through the output end of the inverter circuit; the battery pack is used for outputting the stored electric energy to the PFC circuit when the alternating current power supply fails.

Description

Uninterrupted power supply UPS and power supply system

Technical Field

The application relates to the technical field of power electronics, in particular to an Uninterruptible Power Supply (UPS) and a power supply system.

Background

An Uninterruptible Power Supply (UPS) is a system that can provide an uninterrupted power supply for electronic devices. The UPS is internally provided with a battery, and when the mains supply is normal, the UPS converts the mains supply voltage into the power supply voltage of the electric equipment and provides the power supply voltage for the electric equipment for use. When the mains supply fails, the voltage stored in the battery is converted into the power supply voltage, and the power supply voltage is provided for the electric equipment for use, so that the power supply reliability is ensured.

The UPS mainly comprises a power factor correction circuit, a positive bus, a negative bus, an inverter circuit and the like, wherein the power factor correction circuit performs power factor correction on received electric energy and converts received first alternating current into first direct current, and the first direct current is simultaneously output to the positive bus and the negative bus to charge the positive bus and the negative bus. The inverter circuit converts direct current on the positive bus and the negative bus into second alternating current, and outputs the second alternating current to the electric equipment to supply power to the electric equipment, so that the efficiency of the UPS is improved. During the in-service use, inverter circuit converts the electric energy of positive generating line storage into the positive half cycle signal of second alternating current, and inverter circuit converts the electric energy of negative generating line storage into the negative half cycle signal of alternating current, and above-mentioned UPS framework, the electric energy value of storing equals on positive generating line and the negative generating line, and when the consumer is different to alternating current positive half cycle electric energy and negative half cycle electric energy demand, the electric energy of the storage on positive generating line and the negative generating line can't satisfy the consumer demand to the electric energy. In order to enable the electric energy stored by the positive bus and the negative bus to meet the requirement of the electric equipment, a balance circuit needs to be arranged in the UPS, the balance circuit can realize electric energy adjustment between the positive bus and the negative bus, and the electric energy of the adjusted positive bus and the electric energy of the adjusted negative bus can meet the requirement of the electric equipment on the electric energy. Therefore, the UPS needs to additionally add a balancing circuit, and since the balancing circuit adjusts the electric energy after the power factor correction circuit finishes charging the positive bus and the negative bus, the electric energy on the positive bus and the negative bus needs a certain time to meet the demand of the electric energy by the electric equipment, and the demand of the electric energy by the electric equipment cannot be responded in time.

Disclosure of Invention

The utility model provides an uninterrupted power source UPS and power supply system can satisfy the demand of consumer to the electric energy, reduces the UPS cost, promotes UPS efficiency.

In a first aspect, the present application provides an Uninterruptible Power Supply (UPS), which may include: the power factor correction PFC circuit comprises a PFC circuit, an inverter circuit, a battery pack, a positive bus and a negative bus.

The input end of the PFC circuit is connected with the battery pack, the output end of the PFC circuit is respectively connected with the positive bus and the negative bus, and the PFC circuit is used for receiving the voltage output by the battery pack through the input end of the PFC circuit, converting the voltage output by the battery pack into a first voltage and outputting the first voltage to one or both of the positive bus and the negative bus; the input end of the inverter circuit is connected with the positive bus and the negative bus, and the inverter circuit is used for converting the voltages on the positive bus and the negative bus into a second voltage and outputting the second voltage through the output end of the inverter circuit; the battery pack is used for outputting stored electric energy to the PFC circuit when the alternating current power supply fails.

By adopting the UPS framework, the positive bus can meet the requirement of the electric equipment on the electric energy of the positive half period of the alternating current, and the negative bus can meet the requirement of the electric equipment on the electric energy of the negative half period of the alternating current. Because the PFC circuit can charge for positive bus or negative bus alone, also can charge for positive bus and negative bus together, when the electric energy that the consumer just bus and negative bus demand is the same, the PFC circuit can export first voltage for positive bus and negative bus to charge for positive bus and negative bus, until the electric energy of positive bus and the last storage of negative bus can satisfy the consumer demand to the electric energy. When the electric equipment has different requirements on the electric energy of the positive bus and the electric energy of the negative bus, the time length of the first voltage output to the positive bus by the PFC circuit can be controlled, the time length of the first voltage output to the negative bus by the PFC circuit is controlled, and the electric energy value stored by the positive bus and the electric energy value stored by the negative bus are controlled, so that the electric energy stored by the positive bus and the electric energy stored by the negative bus can meet the requirements of the electric equipment on the electric energy. Therefore, the UPS framework can quickly enable the electric energy stored on the positive bus and the negative bus to meet the requirements of electric equipment by adjusting the charging mode of the positive bus and the negative bus, the design is not required to be provided with a balancing circuit, the cost of the UPS is saved, and the loss of the electric energy on the balancing circuit is reduced due to the fact that the balancing circuit is not required to be arranged, and the efficiency of the UPS is improved.

In one possible implementation, the UPS further includes: and a controller.

The controller is coupled with the PFC circuit and is used for controlling the PFC circuit to convert the voltage output by the battery pack into the first voltage and output the first voltage to one or both of the positive bus and the negative bus.

By adopting the UPS framework, each circuit in the UPS realizes corresponding functions under the control of the controller.

In one possible implementation, the controller is specifically configured to: determining the electric energy required by the positive bus and the electric energy required by the negative bus; outputting the first voltage to the positive bus and the negative bus for storage; when the electric energy stored in a first bus meets the electric energy demand, stopping outputting the first voltage for the first bus, wherein the first bus is the bus with lower electric energy demand in the positive bus and the negative bus; and continuously outputting the first voltage to a second bus until the electric energy stored by the second bus meets the electric energy requirement, wherein the second bus is the bus with higher electric energy requirement in the positive bus and the negative bus.

Adopt above-mentioned UPS framework, can give positive generating line and negative bus with first voltage output, for positive generating line and negative bus simultaneous power supply, when the electric energy of the lower first busbar storage of electric energy demand satisfies the electric energy demand, can stop to charge for the higher first busbar of electric energy demand, and continue to charge to the higher second busbar of electric energy demand, the electric energy of storage satisfies the electric energy demand on the higher second busbar of electric energy demand, thereby when making the electric energy later stage output on positive generating line and the negative bus give the load, can satisfy the demand of load to the electric energy.

In one possible implementation, the controller is specifically configured to: determining the electric energy required by the positive bus and the electric energy required by the negative bus; outputting the first voltage to the third bus, the third bus being one of the positive bus and the negative bus; when the electric energy stored by the third bus meets the electric energy requirement, stopping outputting the first voltage for the third bus; outputting the first voltage to a fourth bus that is the other of the positive bus and the negative bus except for the third bus; and when the electric energy stored by the fourth bus meets the electric energy requirement, stopping outputting the first voltage for the fourth bus.

By adopting the UPS framework, the first voltage can be output to the third bus in the positive bus and the negative bus firstly to charge the third bus, when the electric energy stored by the third bus meets the electric energy requirement, the third bus stops charging, the first voltage is output to the fourth bus except the third bus in the positive bus and the negative bus, when the electric energy stored by the fourth bus meets the electric energy requirement, the fourth bus stops charging, so that the electric energy stored by the positive bus and the electric energy stored by the negative bus can both meet the electric energy requirement, and when the electric energy is output to a load by the positive bus and the negative bus, the stored electric energy meets the electric energy requirement of the load.

In one possible implementation, the PFC circuit includes: the first inductor, the first switch, the second switch, the third switch, the fourth switch and the fifth switch.

Wherein a first end of the first inductor is connected to the ac power source or the battery pack, and a second end of the first inductor is connected to a first electrode of the first switch and a second electrode of the second switch; the second electrode of the first switch is connected with the first end of the positive bus; the first electrode of the second switch is connected with the second end of the negative bus; a first electrode of the third switch is connected with a second end of the first inductor, and a second electrode of the third switch is respectively connected with a first electrode of the fourth switch, the battery pack and a second end of the negative bus; a second electrode of the fourth switch is connected with a second end of the positive bus and a first end of the negative bus; the first electrode of the fifth switch is connected with the second electrode of the third switch, and the second electrode of the fifth switch is connected with the second end of the negative bus.

In one possible implementation, the PFC circuit further includes: and a sixth switch.

Wherein the second electrode of the third switch is connected to the first electrode of the fifth switch and the battery pack through the sixth switch.

In a possible implementation manner, if the ac power source outputs three-phase ac power, the PFC circuit includes: and the single-phase PFC module corresponds to each phase of alternating current in the three-phase alternating current.

The input end of each single-phase PFC module is connected with the battery pack, the output end of each single-phase PFC module is connected with the positive bus and the negative bus, and each first single-phase PFC module is used for receiving corresponding one-phase alternating current or voltage output by the battery pack through the input end of the single-phase PFC circuit, converting the received voltage into the first voltage and outputting the first voltage to the positive bus and/or the negative bus.

In one possible implementation, each of the single-phase PFC modules includes: a second inductor, a seventh switch, an eighth switch, a ninth switch, a tenth switch, and an eleventh switch.

A first end of the second inductor is connected to the battery pack, a second end of the second inductor is connected to a first electrode of the seventh switch and a second electrode of the eighth switch, and the first end of the second inductor is configured to receive a corresponding one-phase alternating current; a second electrode of the seventh switch is connected with a first end of the positive bus; a first electrode of the eighth switch is connected with a second end of the negative bus; a first electrode of the ninth switch is connected with a second end of the second inductor, and a second electrode of the ninth switch is respectively connected with a first electrode of the tenth switch, a second end of the negative bus and the battery pack; a second electrode of the tenth switch is connected to a second end of the positive bus bar and a first end of the negative bus bar; a first electrode of the eleventh switch is connected to a second electrode of the ninth switch, and a second electrode of the eleventh switch is connected to the second end of the negative bus bar.

In one possible implementation, the single-phase PFC module further includes: and a twelfth switch.

The second electrode of the ninth switch is connected to the battery and the first electrode of the eleventh switch through the twelfth switch.

In a second aspect, embodiments of the present application provide a power supply system, which may include a powered device and a UPS provided in the first aspect of the embodiments of the present application and any possible design thereof.

The power utilization equipment is connected with the output end of an inverter circuit in the UPS.

Drawings

Fig. 1 is a first schematic structural diagram of a UPS according to an embodiment of the present disclosure;

fig. 2 is a second schematic structural diagram of a UPS according to an embodiment of the present disclosure;

fig. 3 is a schematic structural diagram of a UPS according to an embodiment of the present disclosure;

fig. 4 is a schematic structural diagram of a UPS according to an embodiment of the present disclosure;

fig. 5 is a first schematic structural diagram of a PFC circuit according to an embodiment of the present disclosure;

fig. 6 is a first schematic diagram illustrating power transmission of a PFC circuit according to an embodiment of the present disclosure;

fig. 7 is a schematic diagram illustrating power transmission of a PFC circuit according to an embodiment of the present disclosure;

fig. 8 is a schematic diagram illustrating power transmission of a PFC circuit according to a third embodiment of the present disclosure;

fig. 9 is a schematic diagram illustrating power transmission of a PFC circuit according to a fourth embodiment of the present disclosure;

fig. 10 is a second schematic structural diagram of a PFC circuit according to an embodiment of the present disclosure;

fig. 11 is a schematic diagram illustrating power transmission of a PFC circuit according to an embodiment of the present disclosure;

fig. 12 is a first schematic diagram of driving signals of a PFC circuit according to an embodiment of the present disclosure;

fig. 13 is a sixth schematic diagram of power transmission of a PFC circuit according to an embodiment of the present disclosure;

fig. 14 is a schematic diagram of a driving signal of a PFC circuit according to an embodiment of the present disclosure;

fig. 15 is a schematic structural diagram of a PFC circuit according to an embodiment of the present application;

fig. 16 is a schematic structural diagram of an inverter circuit according to an embodiment of the present disclosure;

fig. 17 is a schematic structural diagram of a charging circuit according to an embodiment of the present disclosure;

fig. 18 is a first schematic structural diagram of a switching circuit according to an embodiment of the present disclosure;

fig. 19 is a second schematic structural diagram of a switching circuit according to an embodiment of the present disclosure;

fig. 20 is a schematic structural diagram of a switching circuit according to an embodiment of the present application;

FIG. 21 is a schematic diagram of a bypass circuit according to an embodiment of the present disclosure;

fig. 22 is a schematic structural diagram of a UPS according to an embodiment of the present disclosure;

fig. 23 is a sixth schematic structural diagram of a UPS according to an embodiment of the present application;

fig. 24 is a seventh schematic structural diagram of a UPS according to an embodiment of the present disclosure;

fig. 25 is an eighth schematic structural diagram of a UPS according to an embodiment of the present application;

fig. 26 is a schematic structural diagram nine of a UPS according to an embodiment of the present application;

fig. 27 is a schematic structural diagram of a UPS according to an embodiment of the present application;

fig. 28 is an eleventh schematic structural diagram of a UPS according to an embodiment of the present application.

Detailed Description

The embodiments of the present application will be described in detail below with reference to the accompanying drawings.

The particular methods of operation in the method embodiments may also be applied to apparatus embodiments or system embodiments. It is to be noted that "at least one" in the description of the present application means one or more, where a plurality means two or more. In view of this, the "plurality" may also be understood as "at least two" in the embodiments of the present invention. "and/or" describes the association relationship of the associated object, indicating that there may be three relationships, for example, a and/or B, which may indicate: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" generally indicates that the preceding and succeeding related objects are in an "or" relationship, unless otherwise specified. In addition, it is to be understood that the terms first, second, etc. in the description of the present application are used for distinguishing between the descriptions and not necessarily for describing a sequential or chronological order.

It is to be noted that "connected" in the embodiments of the present application refers to an electrical connection, and the connection of two electrical components may be a direct or indirect connection between the two electrical components. For example, a and B may be directly connected, or a and B may be indirectly connected through one or more other electrical elements, for example, a and B are connected, or a and C are directly connected, or C and B are directly connected, and a and B are connected through C.

It should be noted that the switches in the embodiments of the present application are mainly divided into a half-controlled switch and a full-controlled switch, where the half-controlled switch may be a diode and a thyristor, and the full-controlled switch may be one or more of a relay, a Metal Oxide Semiconductor Field Effect Transistor (MOSFET), a Bipolar Junction Transistor (BJT), an Insulated Gate Bipolar Transistor (IGBT), a gallium nitride field effect transistor (GaN), a silicon carbide (SiC) power tube, and the like, and the embodiments of the present application are not listed here.

Specifically, each of the half-controlled switching devices may include a first electrode and a second electrode, and when the potential of the first electrode of the half-controlled switching device is higher than the potential of the second electrode, the half-controlled switching device is turned on, and a current may be transmitted between the first electrode and the second electrode of the half-controlled switching device. When the electric potential of the first electrode of the semi-controlled switch device is lower than the electric potential of the second electrode, the semi-controlled switch device is switched off, and current cannot be transmitted between the first electrode and the second electrode of the semi-controlled switch device.

In particular, each fully-controlled switching device may comprise a first electrode, a second electrode and a control electrode, wherein the control electrode is used for controlling the on or off of the fully-controlled switching device. When the full-control switching device is switched on, current can be transmitted between the first electrode and the second electrode of the full-control switching device, and when the full-control switching device is switched off, current cannot be transmitted between the first electrode and the second electrode of the full-control switching device. Taking a MOSFET as an example, the control electrode of the fully-controlled switching device is a gate, the first electrode of the fully-controlled switching device may be the source of the switching device, and the second electrode may be the drain of the switching device, or the first electrode may be the drain of the switching device and the second electrode may be the source of the switching device.

At present, most of large power supply equipment carries an Uninterruptible Power Supply (UPS) to supply power for the electric equipment uninterruptedly so as to meet the power demand of the electric equipment. When the alternating current power supply is normal, the UPS converts the voltage output by the alternating current power supply into the power supply voltage of the electric equipment and provides the power supply voltage for the electric equipment. When the alternating current power supply fails, the battery pack in the UPS converts the stored voltage into the power supply voltage of the electric equipment and provides the power supply voltage for the electric equipment, so that uninterrupted power supply for the electric equipment is realized.

Fig. 1 shows one possible circuit configuration of a UPS. Referring to fig. 1, the UPS mainly includes: PFC circuit, inverter circuit, group battery, positive BUS BUS + and negative BUS BUS-. The input end of the PFC circuit is connected with an alternating current power supply or a battery pack, the output end of the PFC circuit is connected with a positive BUS BUS + and a negative BUS BUS-, the PFC circuit converts alternating current output by the alternating current power supply into direct current and outputs the direct current to the positive BUS BUS + or the negative BUS BUS-, or converts the voltage of the direct current output by the battery pack and outputs the direct current to the positive BUS BUS + and the negative BUS BUS-. The input end of the inverter circuit is connected with the positive BUS BUS + and the negative BUS BUS-, the output end of the inverter circuit is connected with the electric equipment, the inverter circuit converts the voltage on the positive BUS BUS + and the negative BUS BUS-into alternating current, and the alternating current is output to the electric equipment, so that the electric equipment is powered. Wherein the alternating current is a supply voltage of the electrical equipment.

In actual use, the voltage stored on the positive BUS BUS + is the demand of the electrical equipment for the electrical energy of the positive half period of the supply voltage, and the voltage stored on the negative BUS BUS-is the demand of the electrical equipment for the electrical energy of the negative half period of the supply voltage. The requirements of the electric equipment on the electric energy of the positive half period and the negative half period of the power supply voltage may be equal or unequal, and when the voltages stored on the positive BUS BUS + and the negative BUS BUS-are unequal to the requirements of the electric equipment on the electric energy of the positive half period and the negative half period of the power supply voltage, the power supply effect of the UPS is directly influenced, and the electric equipment cannot normally run in severe cases. In order to guarantee the power supply effect of the UPS, a balancing circuit is generally arranged inside the UPS, and is shown in figure 2 and connected with a positive BUS BUS + and a negative BUS BUS respectively, when the voltage on the positive BUS BUS + and the negative BUS BUS is unequal to the requirements of electric equipment on the electric energy of the alternating current positive half cycle and the alternating current negative half cycle, the adjustment of the electric energy between the positive BUS BUS + and the negative BUS BUS-can be realized through the balancing circuit, and the adjusted voltage of the positive BUS BUS + and the negative BUS BUS-can meet the requirements of the electric equipment on the alternating current.

Although the mode of adjusting the voltage of the positive BUS BUS + and the negative BUS BUS-by adopting the balancing circuit can meet the requirement of the electric energy of the electric equipment, the adjustment mode is to adjust the voltage on the positive BUS BUS + and the negative BUS BUS-by the balancing circuit under the state that the PFC circuit is charged completely for the positive BUS BUS + and the negative BUS BUS-, the mode can not quickly respond to the requirement of the electric equipment on the electric energy of the positive BUS BUS + and the negative BUS BUS-, and due to the arrangement of the balancing circuit, when the electric energy stored on the positive BUS BUS + or the negative BUS BUS-is adjusted by the balancing circuit, the electric energy can also generate corresponding loss on the balancing circuit, the cost of the UPS is increased, and the efficiency of the UPS is also reduced.

In order to solve the above problem, an embodiment of the present application provides a UPS and a power supply system, which are used for quickly meeting the demand of an electrical device on electric energy, reducing the cost of the UPS, and improving the efficiency of the UPS.

As shown in fig. 3, a UPS is provided in accordance with an embodiment of the present invention. Referring to fig. 3, the UPS300 may include: PFC circuit 301, inverter circuit 302, battery pack 303, positive bus 304, and negative bus 305.

The input end of the PFC circuit 301 is connected to the battery pack 303, the output end of the PFC circuit 301 is connected to the positive bus 304 and the negative bus 305, respectively, the PFC circuit 301 is configured to receive the voltage output by the ac power through the input end of the PFC circuit 301, convert the voltage output by the ac power into a first voltage, and output the first voltage to the positive bus 304 or the negative bus 305, or receive the voltage output by the battery pack 303 through the input end of the PFC circuit 301, convert the voltage output by the battery pack 303 into the first voltage, and output the first voltage to one or both of the positive bus 304 and the negative bus 305; the input end of the inverter circuit 302 is connected with the positive bus 304 and the negative bus 305, and the inverter circuit 302 is used for converting the voltages on the positive bus 304 and the negative bus 305 into a second voltage and outputting the second voltage through the output end of the inverter circuit 302; the battery pack 303 is configured to output the stored electric energy to the PFC circuit 301 when the ac power fails.

The positive bus 304 and the negative bus 305 are connected in series, and each of the positive bus 304 and the negative bus 305 includes at least one bus capacitor. When the positive bus 304 or the negative bus 305 includes a plurality of bus capacitors, the plurality of bus capacitors may be connected in series or in parallel, and the present application is not limited thereto.

When the UPS300 provided by the embodiment of the present application is used to supply power to a power consumption device, when the PFC circuit 301 receives a voltage output by the battery pack 303, if the power required by the power consumption device for the positive bus 304 and the negative bus 305 is equal, the PFC circuit 301 may output a first voltage to the positive bus 304 and the negative bus 305, so as to charge the positive bus 304 and the negative bus 305 until the power stored on the positive bus 304 and the negative bus 305 meets the power requirement of the power consumption device. If the demand of the electrical equipment on the positive bus 304 is different from the demand of the electrical equipment on the negative bus 305, the electrical energy stored in the positive bus 304 and the electrical energy stored in the negative bus 305 can be controlled by controlling the time length for the PFC circuit 301 to output the first voltage to the positive bus 304 and controlling the time length for the PFC circuit 301 to output the first voltage to the negative bus 304, so that the electrical energy stored in the positive bus 304 and the electrical energy stored in the negative bus 305 can meet the demand of the electrical equipment. Therefore, by adopting the UPS300, in the charging process of the PFC circuit 301 for the positive bus 304 and the negative bus 305, the requirement of the electric equipment on the electric energy can be met, the requirement of the electric equipment on the electric energy can be quickly met, and an independent balancing circuit is not required to be arranged, so that the cost of the UPS300 is reduced, the loss of the electric energy on the balancing circuit is also reduced, and the efficiency of the UPS is improved.

The voltage value of the first voltage may be greater than or equal to the voltage value of the voltage received by the PFC circuit 301. Since the first voltage is obtained by converting the received voltage by the PFC circuit 301, the voltage value of the first voltage output by the PFC circuit 301 is greater than or equal to the effective value of the alternating current output by the alternating current power source received by the PFC circuit 301 or the voltage value of the direct current output by the battery pack 303, based on the characteristic of the PFC circuit 301 to improve the efficiency of the UPS 300. The output end of the PFC circuit 301 is connected to the positive bus 304 and the negative bus 305, the input end of the inverter circuit 302 is connected to the positive bus 304 and the negative bus 305, and the output end of the inverter circuit 302 can be connected to the electric device, that is, the PFC circuit 301 is connected to the inverter circuit 302 through the positive bus 304 and the negative bus 305 in series. Therefore, one end of the PFC circuit 301 outputting a high level is connected to the positive electrode of the positive bus bar 304, and one end of the PFC circuit 301 outputting a low level is connected to the negative electrode of the negative bus bar 305; similarly, the input terminal of the inverter circuit 302 that receives a high level is connected to the positive electrode of the positive bus 304, and the input terminal of the inverter circuit 302 that receives a low level is connected to the negative electrode of the negative bus 305.

In addition, in the embodiment of the present application, the input terminal of the PFC circuit 301 may be connected to an ac power supply, or may be connected to the battery pack 303. The alternating current power supply can output single-phase alternating current and also can output three-phase alternating current.

Specifically, when the PFC circuit 301 is connected to an ac power supply, the PFC circuit 301 may convert ac power output from the ac power supply into dc power, perform voltage conversion on the dc power, and output the converted dc power to the positive bus 304 or the negative bus 305. When the PFC circuit 301 is connected to the battery pack 303, the PFC circuit 301 may perform voltage conversion on the dc power output from the battery pack 303, and output the dc power after the voltage conversion to the positive bus bar 304 and/or the negative bus bar 305.

In a specific implementation, when the ac power supply is normal, the input end of the PFC circuit 301 receives the electric energy output by the ac power supply, and when the ac power supply fails, the PFC circuit 301 stops receiving the electric energy output by the ac power supply and receives the electric energy output by the battery pack 303. In order to control the power received by the PFC circuit 301, the UPS300 provided in this embodiment of the application may further include a switching circuit 306, as shown in fig. 4, the switching circuit 306 may be configured to control the PFC circuit 301 to receive the ac power output by the ac power source or receive the dc power output by the battery pack 303.

A first input end of the switching circuit 306 is connected to the ac power source and is configured to receive an ac voltage output by the ac power source, a second input end of the switching circuit 306 is connected to the battery pack 303, and an output end of the switching circuit 306 is connected to an input end of the PFC circuit 301. When the switching circuit 306 is in the first state, the PFC circuit 301 receives the ac voltage output by the ac power source, and when the switching circuit 306 is in the second state, the battery pack 303 is connected to the input terminal of the PFC circuit 303.

In actual use, in order to ensure that the UPS300 can uninterruptedly supply power to the electric equipment, sufficient electric energy needs to be stored in the battery pack 303 to supply power to the electric equipment when the ac power supply fails, therefore, the UPS300 provided in this embodiment of the present application further includes a charging circuit, an input end of the charging circuit is connected to the positive bus 304 and the negative bus 305, an output end of the charging circuit is connected to the battery pack 303, and the charging circuit is configured to convert voltages of the positive bus 304 and the negative bus 305 into a third voltage and output the third voltage to the battery pack 303 when the ac power supply is normal.

In a possible implementation, the charging circuit may also be connected between an external power source and the battery pack 303, i.e. the battery pack 303 is charged using the external power source.

Specifically, when the external power supply is a direct-current power supply, the charging circuit converts a voltage output from the direct-current power supply into a charging voltage of the battery pack 303. When the external power supply is an ac power supply, the charging circuit converts ac power output from the ac power supply into dc power and converts the voltage of the dc power into a charging voltage of the battery pack 303. Wherein, the alternating current power supply can be commercial power, a photovoltaic generator system or a wind power generation system.

It should be understood that the PFC circuit 301, the inverter circuit 302 and the switching circuit 306 may be composed of a half-controlled switch, a full-controlled switch, an inductor, a capacitor and the like, and the operating states of the PFC circuit 301, the inverter circuit 302 and the switching circuit 306 may be realized by adjusting the operating states of these devices (e.g., the half-controlled switch and the full-controlled switch).

In this application, the adjustment of the operation state of the above devices may be implemented by a controller, that is, the UPS300 may further include a controller, which may control the PFC circuit 301 to convert the received voltage into a first voltage and output the first voltage to one or both of the positive bus 304 and the negative bus 305, control the inverter circuit 302 to convert the voltages on the positive bus 304 and the negative bus 305 into a second voltage, and control the state of the switching circuit 306.

In one possible implementation, the controller is specifically configured to determine the electrical energy required by the positive bus 304 and the electrical energy required by the negative bus 305; outputting the first voltage to the positive bus 304 and the negative bus 305 for storage; when the electric energy stored in the first bus 304 meets the electric energy demand, the first voltage output to the first bus is stopped, and the first voltage is continuously output to the second bus until the electric energy stored in the second bus meets the electric energy demand. The first bus is a bus with lower electric energy demand in the positive bus 304 and the negative bus 305, and the second bus is a bus with higher electric energy demand in the positive bus 304 and the negative bus 305.

In one possible implementation, the controller is specifically configured to determine the electrical energy required for the positive bus 304 and the electrical energy required for the negative bus 305; outputting the first voltage to a third bus; when the electric energy stored in the third bus meets the electric energy requirement, stopping outputting the first voltage for the third bus; outputting the first voltage to a fourth bus; and when the electric energy stored in the fourth bus meets the electric energy demand, stopping outputting the first voltage for the fourth bus. The third bus bar is one of the positive bus bar 304 and the negative bus bar 305, and the fourth bus bar is the other of the positive bus bar 304 and the negative bus bar 305 except for the third bus bar.

Specifically, if the switches in each circuit of the UPS300 are MOS transistors, the controller may be connected to the gates of the MOS transistors, so as to control the on/off of the MOS transistors to enable the UPS300 to supply power to the electrical devices; if the switches in the circuits of the UPS300 are BJTs, the controller may be connected to bases of the BJTs, so as to control the BJTs to be turned on or off, so that the UPS300 can supply power to the electric devices.

In a specific implementation, the controller may be any one of a Micro Controller Unit (MCU), a Central Processing Unit (CPU), and a Digital Signal Processor (DSP). Of course, the specific form of the controller is not limited to the above example.

Next, specific configurations of the PFC circuit 301, the inverter circuit 302, the switching circuit 306, and the charging circuit in the UPS300 will be described.

1. PFC circuit 301

An input terminal of the PFC circuit 301 may be connected to an output terminal of the switching circuit 306, an output terminal of the PFC circuit 301 is connected to the positive bus bar 304 and the negative bus bar 305, and the PFC circuit 301 may receive a voltage output from the ac power supply through the input terminal of the PFC circuit 301, convert the voltage output from the ac power supply into a first voltage, and output the first voltage to the positive bus bar 304 or the negative bus bar 305, or receive a voltage output from the battery pack 303, convert the voltage output from the battery pack 303 into a first voltage, and output the first voltage to the positive bus bar 304 and/or the negative bus bar 305.

Specifically, when the ac power source outputs a single-phase ac power, the PFC circuit may include a single-phase PFC module. When the ac power source outputs three-phase ac power, the PFC circuit may include a single-phase PFC module corresponding to each of the three-phase ac power.

Wherein the input terminal of each single-phase PFC module can be connected to the battery pack 303 or the ac power source, and the output terminal of each single-phase PFC module is connected to the positive bus bar 304 and the negative bus bar 305 by controlling the state of the switching circuit 306.

Wherein, the effect of setting up single-phase PFC module is: the corresponding one-phase ac power is received through the input terminal of the single-phase PFC circuit or the voltage output from the battery pack 303 is received, the received voltage is converted into a first voltage, and the first voltage is output to the positive bus bar 304 and/or the negative bus bar 305.

For ease of understanding, two specific examples of the PFC circuit 201 will be described below when the ac power supply outputs single-phase ac power and three-phase ac power.

Fig. 5 is a schematic structural diagram of a PFC circuit according to an embodiment of the present disclosure. In fig. 5, the PFC circuit includes a first switch Q1, a second switch Q2, a third switch Q3, a fourth switch Q4, a fifth switch Q5, and a first inductor L1. Where Va and N may be regarded as ac input terminals of the PFC circuit 301, va and Vb may be regarded as dc input terminals of the PFC circuit 301, and Vc and Vd may be regarded as output terminals of the PFC circuit 301. Where C1 may be considered a positive bus 304 and C2 may be considered a negative bus 305. It should be understood that the PFC circuit 301 is a MOS transistor, and other types of switches may be used instead.

The connection relationship of each device in the PFC circuit 301 shown in fig. 5 may be: a first end of the L1 is connected with an alternating current power supply and the battery pack 303 through a switching circuit 306, and a second end of the L1 is connected with a first electrode of the switch Q1 and a second electrode of the switch Q2; the second electrode of Q1 is connected with the first end of the positive bus C1; the first electrode of Q2 is connected with the second end of the negative bus C2; the first electrode of Q3 is connected with the second end of L1, and the second electrode of Q3 is respectively connected with the first electrode of Q4, the battery pack 303 and the first end of the negative bus 305; the second electrode of Q4 is connected to the second end of the positive bus C1 and the first end of the negative bus C2; the first electrode of Q5 is connected to the second electrode of Q3, and the second electrode of Q5 is connected to the second end of the negative bus C2. The first end of the positive bus C1 is the positive electrode of the positive bus C1, the second end of the negative bus C2 is the negative electrode of the negative bus C2, and the second end of the positive bus C1 is connected with the first end of the negative bus C2.

When the PFC circuit 301 shown in fig. 5 is used to charge C1 and C2 through the ac power source, the switching circuit 306 is controlled to be in the first state, at this time, the terminal Va of the PFC circuit 301 is connected to the first terminal of the ac power source, and the terminal N of the PFC circuit 301 is connected to the second terminal of the ac power source.

For the positive half cycle of the ac power output from the ac power source, the operation of the PFC circuit 301 mainly includes two stages, i.e., energy storage and charging. When the PFC circuit 301 operates in the energy storage phase, the ac power output from the ac power supply returns to the ac power supply through L1, Q3, and Q4, and the electric energy output from the ac power supply is stored in L1. When the L1 stores energy, the PFC circuit 301 enters a charging stage, at this time, the electric energy output by the ac power supply returns to the ac power supply through the L1, Q1 output, and C1, the electric energy transmission direction is as shown in fig. 6, and the electric energy output by the ac power supply and the electric energy stored in the L1 are superimposed to charge the positive bus C1. Wherein, the energy stored by C1 can be controlled by controlling the energy storage time of L1.

Similarly, for the negative half cycle of the ac power output from the ac power source, the operation of the PFC circuit 301 includes two phases of energy storage and charging. When the PFC circuit 301 operates at the energy storage node, ac power output by the ac power supply returns to the ac power supply through L1, Q3, and Q4, and at this time, electric energy output by the ac power supply is stored in L1. When the energy storage of the L1 is completed, the PFC circuit 301 enters a charging stage, at this time, the electric energy output by the ac power supply returns to the ac power supply through the C2, the Q2, and the L1, the electric energy transmission direction of which is shown in fig. 7, and the electric energy output by the ac power supply and the electric energy stored in the L1 are superimposed to charge the negative bus C2. The energy stored in the negative bus C2 can be controlled by controlling the energy storage time of L1.

When the positive bus C1 and/or the negative bus C2 is charged by the battery pack 303 using the PFC circuit 301 shown in fig. 5, the switching circuit 306 is controlled to be in the second state, and at this time, the terminals Va and Vb of the PFC circuit 301 are connected to the positive electrode and the negative electrode of the battery pack 303 via the switching circuit 306.

Specifically, the PFC circuit 301 may charge the positive bus C1 and the negative bus C2, respectively, or may charge the positive bus C1 and the negative bus C2 at the same time.

When the PFC circuit 301 charges the positive bus C1, the working process of the PFC circuit 301 mainly includes two stages, i.e., energy storage and charging. When the PFC circuit 301 operates in the energy storage phase, the electric energy returns from the positive pole of the battery pack 303 to the negative pole of the battery pack 303 through the ports Va, L1, Q3 and the port Vb, and the electric energy output by the battery pack 303 is stored in the port L1. When L1 stores energy, the PFC circuit 301 enters the charging phase. At this time, the electric energy returns to the negative electrode of the battery pack 303 from the positive electrode of the battery pack 303 through the ports Va, L1, Q1, C1, Q4 and the port Vb, the electric energy transmission direction is as shown in fig. 8, and the direct current output by the battery pack 303 is overlapped with the electric energy stored in the L1 to charge the positive bus C1. Wherein, the energy stored by C1 can be controlled by controlling the energy storage time of L1.

In one possible implementation, when the PFC circuit 301 is in the energy storage phase, the electric energy may return from the positive pole of the battery pack 303 to the negative pole of the battery pack 303 through the ports Va, L1, Q2, Q5 and the port Vb.

When the PFC circuit 301 charges the negative bus C2, the working process of the PFC circuit 301 mainly includes two stages of energy storage and charging. When the PFC circuit operates in the energy storage phase, the electric energy returns from the positive pole of the battery pack 303 to the negative pole of the battery pack 303 through the ports Va, L1, Q3 and the port Vb, and the electric energy output by the battery pack 303 is stored in the port L1. When L1 stores energy, the PFC circuit 301 enters the charging phase. At this time, the electric energy returns to the negative electrode of the battery pack 303 from the positive electrode of the battery pack 303 through the ports Va, L1, Q3, Q4, and C2 and the charging circuit, the electric energy transmission direction is as shown in fig. 9, and the direct current output by the battery pack 303 is superimposed with the electric energy stored in L1 to charge the negative bus C2. Wherein, the energy stored by C2 can be controlled by controlling the energy storage time of L1.

In a possible implementation manner, in order to reduce the loss during the charging of the negative bus C2, the PFC circuit 301 may further include a sixth switch Q6. Referring to fig. 10, the second electrode of Q3 is connected to the first electrode of Q5 via Q6 and to battery 303.

When the PFC circuit 301 shown in fig. 10 is used to charge the negative bus C2, when the PFC circuit 301 works in the charging phase, the electric energy returns from the positive pole of the battery pack 303 to the negative pole of the battery pack 303 through the ports Va, L1, Q3, Q4, C2, Q5 and the port Vb, the electric energy transmission direction is as shown in fig. 11, and at this time, the direct current output by the battery pack 303 is superimposed with the electric energy stored in L1 to charge the negative bus C2. Wherein, the energy stored by C2 can be controlled by controlling the energy storage time of L1.

The PFC circuit 301 charges the positive bus C1 and the negative bus C2 respectively, and is mainly implemented by controlling on and off of a plurality of switches in the PFC circuit 301, as shown in fig. 12, which is a schematic diagram of states of the switches in the charging process of the PFC circuit 301 for C1 and C2 respectively. Wherein, when the state of the switch is high level, the switch is turned on. Similarly, when the state of the switch is low level, the switch is off.

When the PFC circuit 301 charges the positive bus C1 and the negative bus C2, the working process of the PFC circuit 301 mainly includes two stages of energy storage and charging. When the PFC circuit operates in the energy storage phase, the electric energy returns from the positive pole of the battery pack 303 to the negative pole of the battery pack 303 through the ports Va, L1, Q3, Q6 and the port Vb, and the electric energy output by the battery pack 303 is stored in the port L1. When the L1 stores energy, the PFC circuit 301 enters a charging stage, at this time, the electric energy starts from the positive electrode of the battery pack 303 and returns to the negative electrode of the battery pack 303 through L1, Q1, C2, and Q5, the electric energy transmission direction is as shown in fig. 13, and at this time, the direct current output by the battery pack 303 and the electric energy stored in the L1 are superimposed to charge the positive bus C1 and the negative bus C2. Wherein, the energy stored by C1 and C2 can be controlled by controlling the energy storage time of L1.

Specifically, when PFC circuit 301 charges positive bus C1 and negative bus C2 simultaneously through battery pack 303, respectively, the state of each switch can be seen in fig. 14.

Fig. 15 is a schematic structural diagram of a PFC circuit according to an embodiment of the present disclosure. In fig. 15, the PFC circuit 301 includes three single-phase PFC modules, each of which corresponds one-to-one to each of three-phase alternating currents output from the alternating-current power supply. Each PFC module includes a seventh switch Q7, an eighth switch Q8, a ninth switch Q9, a tenth switch Q10, an eleventh switch Q11, and a first inductor L2. VA, VB, and VC may be regarded as ac input terminals of the PFC circuit 301, VA, VB, VC, VD1, VD2, and VD3 may be regarded as dc input terminals of the PFC circuit 301, and CE and VF may be regarded as output terminals of the PFC circuit 301.

The connection relationship of the devices in each single-phase PFC module in the PFC circuit 301 shown in fig. 15 may be: a first end of the L2 is connected with an alternating current power supply or a battery pack 303 through a switching circuit 306, a second end of the L2 is connected with a first electrode of the Q7 and a second electrode of the Q8, and the first end of the L2 is used for receiving corresponding one-phase alternating current; the second electrode of Q7 is connected with a positive bus C1; the first electrode of Q8 is connected with a negative bus C2; the first electrode of Q9 is connected with the second end of L2, and the second electrode of Q9 is respectively connected with the first electrode of Q10 and the second end of the negative bus C2 and the battery pack 303; the second electrode of Q10 is connected to the second end of the positive bus bar C1 and the second end of the negative bus bar C2; the first electrode of Q11 is connected to the second electrode of Q9, and the second electrode of Q11 is connected to the second end of the negative bus C2.

When the PFC circuit 301 shown in fig. 15 is used to charge the positive bus C1 and the negative bus C2 through the ac power source, the switching circuit 306 is controlled to be in the first state, at this time, the endpoint VA of the PFC circuit 301 is connected to the first endpoint of the ac power source through the switching circuit 306, the endpoint VB is connected to the second endpoint of the ac power source through the switching circuit 306, and the endpoint VC is connected to the third endpoint of the ac power source through the switching circuit. The first end point of the alternating current power supply outputs first-phase alternating current in three-phase alternating current, the second end point of the alternating current power supply outputs second-phase alternating current in the three-phase alternating current, and the second end point of the alternating current power supply outputs third-phase alternating current in the three-phase alternating current. The first-phase alternating current may be an a-phase alternating current, the second-phase alternating current may be a B-phase alternating current, and the third-phase alternating current may be a C-phase alternating current.

Taking the first-phase ac power as an example for charging the positive bus C1, the working process of the PFC circuit 301 mainly includes two stages, i.e., energy storage and charging, for the positive half cycle of the first-phase ac power. When the PFC circuit 301 works in the energy storage phase, the first phase ac output by the ac power supply returns to the ac power supply through the ports VA, L2, Q9, Q10, and N, and at this time, the electric energy output by the ac power supply is stored in the port L2. When the energy storage of the L2 is finished, the PFC circuit enters a charging stage, and at the moment, the electric energy output by the alternating current power supply returns to the alternating current power supply through the ports VA, L2, Q7, C1 and N. At the moment, the electric energy output by the alternating current power supply and the electric energy stored in the L1 are superposed to charge the positive bus C1. Wherein, the energy stored by the C1 can be controlled by controlling the energy storage time of the L2.

For the negative half cycle of the first phase ac power, the operation of the PFC circuit 301 mainly includes two phases of energy storage and charging. When the PFC circuit 301 operates in the energy storage phase, the first phase ac output by the ac power supply returns to the ac power supply through the ports N, Q10, Q9, and L2 and the endpoint VA, and at this time, the electric energy output by the ac power supply is stored in the port L2. When the energy storage of the L2 is finished, the PFC circuit enters a charging stage, and at the moment, the electric energy output by the alternating current power supply returns to the alternating current power supply through the ports N, C2, Q11, Q9, L2 and the port VA. At the moment, the electric energy output by the alternating current power supply and the electric energy stored in the L1 are superposed to charge the negative bus C2. Wherein, the energy stored by C2 can be controlled by controlling the energy storage time of L2.

When the positive bus C1 and/or the negative bus C2 is charged by the battery pack 303 using the PFC circuit 301 shown in fig. 15, the switching circuit 306 is controlled to be in the second state, and at this time, the terminals VA, VB, VC, VD1, VD2, and VD3 of the PFC circuit 301 are connected to the positive electrode and the negative electrode of the battery pack 303 through the switching circuit 306.

When the PFC circuit 301 charges the positive bus C1, the working process of the PFC circuit 301 mainly includes two stages, i.e., energy storage and charging. When the PFC circuit 301 operates in the energy storage phase, the electric energy returns from the positive electrode of the battery pack 303 to the negative electrode of the battery pack 303 through the ports VA, L2, Q9 and the port VD1, and the electric energy output by the battery pack 303 is stored in the port L2. When L2 stores energy, the PFC circuit 301 enters the charging phase. At this time, power is returned from the positive pole of the battery pack 303 to the negative pole of the battery pack 303 through the ports VA, L2, Q7, C1, Q10 and the port VD 1. Wherein, the energy stored by C1 can be controlled by controlling the energy storage time of L2.

In one possible implementation, when the PFC circuit 301 is in the energy storage phase, the power may return from the positive pole of the battery pack 303 to the negative pole of the battery pack 303 through the ports VA, L2, Q8, Q11 and the port VD 1.

When the PFC circuit 301 charges the negative bus C2, the working process of the PFC circuit 301 mainly includes two stages, i.e., energy storage and charging. When the PFC circuit operates in the energy storage phase, the electric energy returns from the positive electrode of the battery pack 303 to the negative electrode of the battery pack 303 through the ports VA, L2, Q9 and the port VD1, and the electric energy output by the battery pack 303 is stored in the port L2. When L2 stores energy, the PFC circuit 301 enters the charging phase. At this time, the electric energy returns from the positive electrode of the battery pack 303 to the negative electrode of the battery pack 303 through the ports VA, L2, Q9, Q10, C2, Q11 and the port VD 1. Wherein, the energy stored by C2 can be controlled by controlling the energy storage time of L2.

In a possible implementation manner, in order to reduce the loss during the charging of the negative bus C2, the PFC circuit 301 may further include a twelfth switch Q12. Wherein the second electrode of Q9 is connected to the first electrode of Q11 and the battery 303 through Q12.

When the PFC circuit 301 charges the positive bus C1 and the negative bus C2, the working process of the PFC circuit 301 mainly includes two stages of energy storage and charging. When the PFC circuit operates in the energy storage phase, the electric energy returns from the positive pole of the battery pack 303 to the negative pole of the battery pack 303 through the ports VA, L2, Q9 and the port VD1, and the electric energy output by the battery pack 303 is stored in the port L2. When the energy storage of L1 is finished, the PFC circuit 301 enters a charging stage, and at this time, the electric energy starts from the positive electrode of the battery pack 303 and returns to the negative electrode of the battery pack 303 through the ports VA, L2, Q7, C1, C2, Q11 and the port VD1, and at this time, the direct current output by the battery pack 303 and the electric energy stored in L1 are superimposed to charge the positive bus C1. Wherein, the energy stored by C1 and C2 can be controlled by controlling the energy storage time of L2.

2. Inverter circuit 302

The input end of the inverter circuit 302 may be connected to the positive bus 304 and the negative bus 305, the output end of the inverter circuit 302 is connected to the electric device, and the inverter circuit 302 is configured to convert the voltages on the positive bus 304 and the negative bus 305 into a second voltage and output the second voltage to the electric device, so as to supply power to the electric device. The second voltage may be a rated operating voltage of the electric device.

Specifically, if the power supply voltage of the electrical equipment is single-phase alternating current, the inverter circuit includes a single-phase inverter module, and if the power supply voltage of the electrical equipment is three-phase alternating current, the inverter circuit includes a single-phase inverter module corresponding to each phase of alternating current in the three-phase alternating current one to one.

The first input end of the single-phase inversion module may be connected to the first end of the positive bus 304, the second end of the single-phase inversion module may be connected to the second end of the negative bus 305, the neutral point of the single-phase inversion module is connected to the second end of the positive bus 304 and the first end of the negative bus 305, and the output end of the single-phase inversion module is connected to the electrical equipment.

In the embodiment of the present application, the single-phase inverter module may have an existing structure, for example, the single-phase inverter module may be an I-type inverter circuit. Taking the power supply voltage of the electric device as a single-phase alternating current as an example, referring to fig. 16, the I-type inverter circuit may include four switches K1 to K4, a freewheeling inductor L3, and diodes D1 and D2. The K1 to K4 are connected in series in sequence, a first electrode of the K1 may serve as a first input end of the inverter circuit 302 and a first end of the positive bus 304, a second electrode of the K4 may serve as a second input end of the inverter circuit 302 and is connected to a second segment of the negative bus 305, and a second end of the inductor L3 serves as an output end of the inverter circuit 302 and is connected to the electric equipment (at this time, the output end of the inductor L3 outputs a second voltage).

By adopting the inverter circuit, the voltage of the direct current on the positive bus 304 and the negative bus 305 can be regulated and inverted.

3. Charging circuit

The input end of the charging circuit is connected with the positive bus 304 and the negative bus 305 respectively, the output end of the charging circuit is connected with the battery pack 303, and the charging circuit is used for converting the voltages on the positive bus 304 and the negative bus 305 into a third voltage and outputting the third voltage to the battery pack 303 when the alternating current power supply is normal. The third voltage is a charging voltage of the battery pack 303.

Wherein, the charging circuit can include: an inverter and an isolation transformer; the primary winding of the isolation transformer is coupled to the inverter, and the secondary winding of the isolation transformer is coupled to the battery pack 303.

The inverter is composed of switches, an input end of the inverter is connected with the positive bus 304 and the negative bus 305, an output end of the inverter is connected with a primary winding of the isolation transformer, and the inverter can convert a part of direct current stored on the positive bus 304 and the negative bus 305 into alternating current and output the alternating current to the primary winding of the isolation transformer. The secondary winding of the isolation transformer is connected to the battery pack 303, and the isolation transformer can regulate the received ac power to obtain a third voltage, and output the third voltage to the battery pack 303.

By adopting the charging circuit, the voltage on the positive bus 304 and the voltage on the negative bus 305 can be regulated and inverted, and the isolation between the positive bus and the negative bus and the battery pack 303 can be realized.

Illustratively, the structure of the charging circuit may be as shown in fig. 17. In fig. 17, the charging circuit may include a thirteenth switch Q13, a fourteenth switch Q14, a fifteenth switch Q15, a sixteenth switch Q16, a third inductor L4, and a fourth inductor L5. Wherein the inductor L4 and the inductor L5 are coupled.

In a possible implementation manner, in order to control the charging time of the battery pack 303 by the positive bus 304 and the negative bus 305, in this embodiment, the charging circuit may further include a switch Q17, and the switch Q17 may be connected between the inductor L4 and the positive electrode of the battery pack 303, and when Q17 is turned on, the switch Q17 is configured as a charging path of the battery pack 303, and when Q17 is turned off, the charging path is turned off, and the battery pack 303 cannot be charged.

The connection relationship between the devices in the charging circuit may be as follows: a first electrode of Q13 is connected to a first end of positive bus 304, and a second electrode of Q13 is connected to a first end of L4 and a first electrode of Q14; the second electrode of Q14 and the first electrode of Q15 are connected to the second end of the positive bus bar 304; a first electrode of Q15 is connected to a first end of negative bus 305, a second electrode of Q15 is connected to a first end of L5 and a first electrode of Q16; the second electrode of Q16 is connected to the second end of the negative bus 305; the second end of the L4 is connected with the first electrode of the Q17; the second end of L5 is connected to the negative pole of battery 303; the second electrode of Q17 is connected to the positive electrode of the battery 303.

When the positive bus 304 and the negative bus 305 charge the battery pack 303, the Q17 is controlled to be switched on, the inverter receives the voltage output by the positive bus 304 and the negative bus 305, the plurality of switches form a voltage regulating circuit to convert the voltage on the positive bus 304 and the negative bus 305 into the charging voltage of the battery pack, and the charging voltage is output to the battery pack 303 through the Q17 to charge the battery pack 303.

4. Switching circuit 306

A first input terminal of the switching circuit 306 is connected to the ac power source, a second input terminal of the switching circuit 306 is connected to the battery pack 303, an output terminal of the switching circuit 306 is connected to an input terminal of the PFC circuit, and the switching circuit 306 can control the devices connected to the input terminal of the PFC circuit 301 and the source of the received power.

Specifically, when the switching circuit 306 is in the first state, the input terminal of the PFC circuit 301 is connected to the ac power source and receives the ac power output from the ac power source. When the switching circuit 306 is in the second state, the input terminal of the PFC circuit 301 is connected to the battery pack 303 and receives the dc power output by the battery pack 303.

The specific structure of the switching circuit 306 is given below.

The switching circuit 306 may include a first switch module and a second switch module.

One end of the first switch module is connected with the alternating current power supply, and the other end of the first switch module is connected with the PFC circuit 301; one end of the second switch module is connected with the battery pack module, and the other end of the second switch module is connected with the battery module.

For ease of understanding, two specific examples of PFC circuit 301 are given below.

Fig. 18 is a schematic structural diagram of a PFC circuit 301 according to an embodiment of the present disclosure. In fig. 18, the switch A1 may be regarded as a first switch module, the switches A2 and A3 may be regarded as a second switch module, va may be regarded as a first port of the input terminal of the PFC circuit 301, and Vb may be regarded as a second port of the input terminal of the PFC circuit 301.

It should be noted that, in order to reduce the number of the power transmission lines of the switching circuit 306 and the input ports of the PFC circuit 301, the output terminals of the switches A1 and A2 are connected to the same input port of the PFC circuit 301, that is, the input port multiplexing of the PFC circuit 301 is realized. Certainly, in order to implement isolation between two power supplies, the input port in the PFC circuit 301 may also adopt an multiplexing-free manner, which is not limited herein.

Specifically, when the ac power source outputs power for the PFC circuit 301, in order to ensure that when the ac power source is initially connected, the start current is too large to cause damage to the device inside the UPS300, the first switch module may further include a start module, as shown in fig. 19, the start module may include a current limiting resistor R1 and a switch K4, when the ac power source fails, the switch A4 may be controlled to be turned on, and at this time, the current limiting resistor R1 performs current limiting processing on the current input to the PFC circuit 301, so as to ensure safety of the device inside the UPS300, and after the current output by the ac power source is stable, the switch A1 is controlled to be closed, and the connection of the switch A4 is disconnected, so that power loss of the switching circuit 306 is saved.

Fig. 20 is a schematic structural diagram of another PFC circuit 301 according to an embodiment of the present disclosure. In fig. 20, the switches A5, A6, and A7 may be regarded as the first switch module, and the switches A8, A9, a10, and a11 may be regarded as the second switch module. VA, VB, VC, and VD can be considered as input ports of the PFC circuit 301.

Specifically, when the ac power supply outputs power for the PFC circuit 301, in order to ensure that when the ac power supply is initially connected, the start current is too large, which may cause damage to devices inside the UPS300, the first switch module may further include three start modules, and the three start modules are respectively connected in parallel with the switches A8, A9, and a 10. When the ac power source is initially connected, the start module performs current limiting processing on the current input to the PFC circuit 301, so as to ensure the safety of the internal devices of the UPS300, and after the current output by the ac power source is stable, the control switches A8, A9, and a10 are closed, and the connection of the start module is disconnected, so that the power loss of the switching circuit 306 is saved.

It should be noted that, the structure of the starting module can be seen from fig. 19, and the description is not repeated here.

In practical use, the mode that the PFC circuit 301 and the inverter circuit 302 are connected in series is mainly for eliminating ripple signals of the ac power supply to ensure the quality of electric energy provided for the electric devices, when the ac power output by the ac power supply carries a small number of ripple signals, the quality of the ac power output by the ac power supply is good, and in order to ensure the power supply efficiency, the UPS300 provided in the embodiment of the present application may further include a bypass circuit.

Wherein, bypass circuit's output is connected with alternating current power supply, and bypass circuit's output is connected with inverter circuit 302's output, and when alternating current ripple signal that alternating current power supply output was less, the present alternating current quality of sign is better, can directly provide the consumer with alternating current that alternating current power supply output through bypass circuit.

In particular, when the supply voltage of the consumer is single-phase ac, the bypass circuit may include a single-phase bypass module, an input of which may be connected to the ac power source and the other end of which may be connected to the consumer. When the alternating current power supply outputs three-phase alternating current and the power supply voltage of the electric equipment is three-phase alternating current, the bypass circuit can comprise three single-phase bypass modules, the input end of each bypass module is connected with the alternating current power supply, receives one phase of alternating current of the three phases of electricity, and outputs the received one-phase alternating current to the electric equipment. It should be understood that the structure of each single phase bypass module can be seen in fig. 21.

In conjunction with the above description, an example of a UPS provided by the embodiments of the present application may be as shown in fig. 22.

The PFC circuit comprises MOS tubes Q1/Q2/Q3/Q4/Q5 and an inductor L1. The first end of the L1 is connected with the output end of the switching circuit, and the second end of the L1 is connected with the first electrode of the Q1 and the second electrode of the Q2; the second electrode of Q1 is connected with the first end of the positive bus C1; the first electrode of Q2 is connected with the second end of the negative bus C2; a first electrode of the Q3 is connected with a second end of the first inductor, and a second electrode of the Q3 is respectively connected with a first electrode of the Q4, the battery pack and a first electrode of the Q6; the second electrode of Q4 is connected with the second end of the positive bus C1 and the first end of the negative bus C2; the first electrode of Q5 is connected to the second electrode of Q3, and the second electrode of Q5 is connected to the second end of the negative bus C2.

In a possible implementation manner, the PFC circuit further includes a MOS transistor Q6, and a second electrode of the Q3 is connected to the battery through the first electrodes of Q6 and Q5.

Specifically, referring to fig. 23, the first electrode of Q6 is connected to the second electrode of Q3, and the second electrode of Q6 is connected to the first electrode of Q5.

In a possible implementation manner, because the switches Q1 and Q2 are turned on after the L1 finishes storing energy, the voltage of the L1 after storing energy is superposed with the electric energy output by the ac power supply or the battery pack is greater than the bus voltage, in order to reduce the control difficulty of the controller, the MOS transistor Q1 may be replaced by a diode D1, and the circuit structure thereof is shown in fig. 24. In actual use, the MOS transistor Q2 may also be replaced by a diode D2, and the circuit structure thereof can be seen in fig. 25.

The inverter circuit comprises MOS tubes Q7/Q8/Q/Q10, diodes D3/D4 and an inductor L2. Wherein, the first electrode of the switch Q7 is connected with the positive bus C1, and the second electrode of Q7 is connected with the cathode of D3 and the first electrode of Q8; the second electrode of Q8 is connected with the first electrode of Q9 and the second end of the positive bus C1; a first electrode of Q9 is connected with a first end of the negative bus bar C2, and a second electrode of Q9 is connected with a first electrode of Q10 and an anode of D4; the second end of Q10 is connected with the second end of the negative bus C2; the anode of the D3 is connected with the cathode of the D4 and the second end of the positive bus C1; the cathode of the D4 is connected with the first end of the negative bus C2; the first end of L2 is connected with the second electrode of Q8, and the second end of L2 is connected with the bypass circuit and the electric equipment.

In the charging circuit, MOS tubes Q11/Q12/Q13/Q14/Q15 and inductors L4 and L5 are included. Wherein, a first end of Q11 is connected with a first end of the positive bus C1, and a second end of Q11 is connected with a first end of L4 and a first electrode of Q12; the second electrode of Q12 is connected with the second end of the positive bus C1 and the first electrode of Q13; a first electrode of Q13 is connected with a first electrode of the negative bus C2, and a second electrode of Q13 is connected with a first electrode of Q14 and a first end of L5; the second electrode of Q14 is connected with the second end of the negative bus C2; a second end of the L4 is connected with a first electrode of the Q15; the second end of the L5 is connected with the negative electrode of the battery pack; the second electrode of Q15 is connected to the positive electrode of the battery. Wherein L4 and L5 are coupled.

In the switching circuit, relays A1/A2/A3/A4 and a resistor R1 are included. The first electrode of A1 is connected with an alternating current power supply, and the second electrode of A1 is connected with the first end of L1; the first electrode of A2 is connected with the positive electrode of the battery pack, and the second electrode of A2 is connected with the first end of L1; the first electrode of A3 is connected with the cathode of the battery pack, and the second electrode of A3 is connected with the second electrode of Q5; the first electrode of A4 is connected with an alternating current power supply, and the second electrode of A4 is connected with a resistor R1; the second end of R1 is connected to the first end of L1. Wherein A4 and R1 form a starting module.

In the bypass circuit, a control switch D5/D6/D7/D8 and a single-pole double-throw switch A5 are included. Wherein, the cathode of D5 is connected with an alternating current power supply, and the anode of D5 is connected with the input end of A5; the anode of D6 is connected with an alternating current power supply, and the cathode of D6 is connected with the input end of A5; the first output end of A5 is connected with an alternating current power supply, and the second output end of A5 is connected with the second end of L2; the anode of the D7 is connected with the input end of the A5, and the cathode of the D7 is connected with the second end of the L2; the anode of D8 is connected with the second end of L2; the cathode of the D8 is connected with the electric equipment.

When the UPS shown in fig. 22 is used to supply power to electric devices, a is used as an input of the UPS, and B and C are used as outputs of the UPS and connected to the electric devices.

By adopting the UPS, the switching circuit, the PFC circuit and the inverter circuit are sequentially connected behind the alternating current power supply. In the switching circuit, A1 is closed, and the ac power supply outputs the output single-phase ac power to the PFC circuit. In the PFC circuit, for a positive half-cycle signal of single-phase alternating current, when the voltage value of the single-phase alternating current is smaller than the potential of the positive terminal of C1, the single-phase alternating current output by an alternating current power supply is stored to L1 through Q3 and Q4, and when the sum of the voltage value of the single-phase alternating current and the voltage values at two ends of L1 is larger than the potential of the positive terminal of C1, the electric energy output by the alternating current power supply and the electric energy stored by L1 are rectified, and a first voltage is output to C1. Similarly, for the negative half-cycle signal of the single-phase alternating current, when the voltage value of the single-phase alternating current is smaller than the positive terminal potential of C2, the single-phase alternating current output by the alternating current power supply is stored to L1 through Q3 and Q4, and when the sum of the voltage value of the single-phase alternating current and the voltage values at two ends of L1 is larger than the positive terminal voltage of C2, the electric energy output by the alternating current power supply and the electric energy stored in L1 are rectified, and a first voltage is output to C2. The inverter circuit converts the electric energy on the C1 into a positive half-period signal of the alternating current, the inverter circuit converts the electric energy of the C2 into a negative half-period signal of the alternating current, and the positive half-period signal and the negative half-period signal form a second voltage and are output to the electric equipment.

When an alternating current power supply fails, the connection between the A1 and the first end of the L1 is disconnected, the A2 and the A3 are controlled to be conducted, the anode of the battery pack is connected with the first end of the L1, the cathode of the battery pack is connected with the second electrode of the Q6, the battery pack can charge the C1 through the L1, the Q1, the C1, the Q4 and the Q6, can charge the C2 through the L1, the Q3, the Q4, the C2 and the Q5, and can simultaneously charge the C1 and the C2 through the Q1, the C2 and the Q5.

It should be understood that when the UPS is used to supply power to a power consumer, if the ac power source supplies power to the PFC circuit, the charging amounts of C1 and C2 can be adjusted by adjusting the energy storage time of L1. If the battery pack provides electric energy for the PFC circuit, the PFC circuit can be adopted to respectively charge the C1 and the C2, and the charging quantity of the C1 and the C2 can be adjusted by adjusting the energy storage time of the L1. C1 and C2 can also be charged simultaneously through the PFC circuit until the minimum charging amount of C1 and C2 demands is charged, and then the capacitor which is respectively charged for C1 and C2 and does not meet the requirement of the charging amount at that time is additionally charged until the charging amounts of C1 and C2 both meet the requirement of the electric equipment on the electric quantity. Because when charging for C1 and C2, PFC circuit can be through adjusting on off state control charge mode, can realize C1 and C2 to the demand of charging amount, need not to set up extra device and carry out the electric energy adjustment, and its charge efficiency is high, and owing to need not to set up extra device, has reduced UPS's cost and has promoted UPS's efficiency.

It should be noted that, the above description of the structure of the UPS is only an example, and in actual use, the UPS provided by the present application may further include other structures according to different types of switching devices in the PFC circuit, the inverter circuit, the charging circuit, the switching circuit, and the bypass circuit, and since the operation principles of the other structures are compatible, the present application is not described herein.

In conjunction with the above description, another UPS provided in the embodiments of the present application may be shown in fig. 26, for example.

In the PFC circuit, three PFC modules can be included, and each PFC module comprises a MOS tube Q1/Q2/Q3/Q4/Q5 and an inductor L1. The first end of the L1 is connected with the output end of the switching circuit, and the second end of the L1 is connected with the first electrode of the Q1 and the second electrode of the Q2; the second electrode of Q1 is connected with the first end of the positive bus C1; the first electrode of Q2 is connected with the second end of the negative bus C2; a first electrode of the Q3 is connected with a second end of the first inductor, and a second electrode of the Q3 is respectively connected with a first electrode of the Q4, the battery pack and a first electrode of the Q6; the second electrode of Q4 is connected with the second end of the positive bus C1 and the first end of the negative bus C2; the first electrode of Q5 is connected to the second electrode of Q3, and the second electrode of Q5 is connected to the second end of the negative bus C2.

In a possible implementation manner, each PFC module further includes a MOS transistor Q6, and the second electrode of Q3 is connected to the battery pack through the first electrodes of Q6 and Q5. As shown in fig. 27, the first electrode of Q6 is connected to the second electrode of Q3, and the second electrode of Q6 is connected to the first electrode of Q5.

In a possible implementation manner, since three PFC modules are connected in parallel, in order to reduce the number of devices in the PFC circuit, in this embodiment, the switch Q5 may be multiplexed, as shown in fig. 28, where the first end of Q5 is connected to the second electrodes of all Q3, and the second electrode of Q5 is connected to the negative bus C2.

In a possible implementation manner, because the switches Q1 and Q2 are turned on after the L1 finishes storing energy, the L1 stores energy and then is superposed with electric energy output by an alternating current power supply or a battery pack and then is greater than bus voltage, and in order to reduce the control difficulty of the controller, the diode D1 can be used to replace the MOS transistor Q1. In actual use, the diode D2 can be used to replace the MOS transistor Q2.

The inverter circuit comprises MOS transistors Q7/Q8/Q/Q10, diodes D3/D4 and an inductor L2. Wherein, the first electrode of the switch Q7 is connected with the positive bus C1, and the second electrode of Q7 is connected with the cathode of D3 and the first electrode of Q8; the second electrode of Q8 is connected with the first electrode of Q9 and the second end of the positive bus C1; the first electrode of Q9 is connected with the first end of the negative bus C2, and the second electrode of Q9 is connected with the first electrode of Q10 and the anode of D4; the second end of Q10 is connected with the second end of the negative bus C2; the anode of the D3 is connected with the cathode of the D4 and the second end of the positive bus C1; the cathode of the D4 is connected with the first end of the negative bus C2; the first end of L2 is connected with the second electrode of Q8, and the second end of L2 is connected with the bypass circuit and the electric equipment.

In the charging circuit, MOS tubes Q11/Q12/Q13/Q14/Q15 and inductors L4 and L5 are included. Wherein, a first end of Q11 is connected with a first end of the positive bus C1, and a second end of Q11 is connected with a first end of L4 and a first electrode of Q12; the second electrode of Q12 is connected with the second end of the positive bus C1 and the first electrode of Q13; a first electrode of Q13 is connected with a first electrode of the negative bus C2, and a second electrode of Q13 is connected with a first electrode of Q14 and a first end of L5; the second electrode of Q14 is connected with the second end of the negative bus C2; the second end of L4 is connected with the first electrode of Q15; the second end of the L5 is connected with the negative electrode of the battery pack; the second electrode of Q15 is connected to the positive electrode of the battery. L4 and L5 are coupled.

The switching circuit comprises relays A1/A2/A3/A4/A5/A6/A7. Wherein, A1, A2 and A3 are respectively corresponding to the three L1 one by one. The first electrode of A1 is connected with the first output end of an alternating current power supply, and the second electrode of A1 is connected with the first end of the corresponding L1; the first electrode of A2 is connected with the second output end of the alternating current power supply, and the second electrode of A2 is connected with the first end of the corresponding L1; the first electrode of A3 is connected with the third output end of the alternating current power supply, and the second electrode of A3 is connected with the first end of the corresponding L1; the first electrode of A4 is connected with the positive electrode of the battery pack, and the second electrode of A4 is connected with the second electrode of A1; the first electrode of A5 is connected with the positive electrode of the battery pack, and the second electrode of A5 is connected with the second electrode of A2; the first electrode of A6 is connected with the positive electrode of the battery pack, and the second electrode of A6 is connected with the second electrode of A3; the first electrode of A7 is connected to the negative electrode of the battery, and the second electrode of A4 is connected to the second electrode of Q6.

In practical use, the two ends of A1, A2 and A3 may be provided with a start module to limit the input of the current value of the PFC when the ac power supply is initially started. It should be noted that the structure of the starting module can be seen from fig. 22, and the description is not repeated here.

In the bypass circuit, a control switch D5/D6/D7/D8 and a single-pole double-throw switch A8 are included. Wherein, the cathode of D5 is connected with an alternating current power supply, and the anode of D5 is connected with the input end of A8; the anode of D6 is connected with an alternating current power supply, and the cathode of D6 is connected with the input end of A8; the first output end of A8 is connected with an alternating current power supply, and the second output end of A8 is connected with the second end of L2; the anode of the D7 is connected with the input end of the A8, and the cathode of the D7 is connected with the second end of the L2; the anode of D8 is connected with the second end of L2; the cathode of the D8 is connected with the electric equipment.

When the UPS shown in fig. 22 is used to supply power to consumers, VA, VB, and VC are used as input terminals of the UPS, and VE and VF are used as output terminals of the UPS and connected to the consumers.

By adopting the UPS, the switching circuit, the PFC circuit and the inverter circuit are sequentially connected behind the alternating current power supply. In the switching circuit, A1, A2, and A3 are closed, and the ac power supply outputs the output three-phase ac power to the PFC circuit. Taking the first-phase alternating current in the single-phase alternating current received by the port VA as an example, for a positive half-cycle signal of the first-phase alternating current in the PFC circuit, when the voltage value of the first-phase alternating current is smaller than the positive terminal potential of C1, the first-phase alternating current output by the alternating current power supply is stored to L1 through Q3 and Q4, and when the sum of the voltage value of the first-phase alternating current and the voltage values at two ends of L1 is larger than the positive terminal potential of C1, the electric energy output by the alternating current power supply and the electric energy stored in L1 are rectified to output the first voltage to C1. Similarly, for the negative half-cycle signal of the first-phase alternating current, when the voltage value of the first-phase alternating current is smaller than the positive terminal potential of C2, the single-phase alternating current output by the alternating current power supply is stored to L1 through Q3 and Q4, and when the sum of the voltage value of the first-phase alternating current and the voltage values at two ends of L1 is larger than the positive terminal voltage of C2, the electric energy output by the alternating current power supply and the electric energy stored by L1 are rectified, and the first voltage is output to C2. The inverter circuit converts the electric energy on the C1 into a positive half-cycle signal of alternating current, the inverter circuit converts the electric energy on the C2 into a negative half-cycle signal of the alternating current, and the positive half-cycle signal and the negative half-cycle signal form a second voltage and are output to the electric equipment.

When the alternating current power supply fails, the controls A1, A2 and A3 are disconnected, the controls A4, A5, A6 and A7 are conducted, the positive electrode of the battery pack is connected with the first ends of the three L1, the negative electrode of the battery pack is connected with the second electrode of the Q6, the battery pack can charge the C1 through the L1, the Q1, the C1, the Q4 and the Q6, can charge the C2 through the L1, the Q3, the Q4, the C2 and the Q5, and can simultaneously charge the C1 and the C2 through the Q1, the C2 and the Q5.

It should be understood that when the UPS is used to supply power to the electric device, if the ac power source provides power to the PFC circuit, the charging amounts of C1 and C2 can be adjusted by adjusting the energy storage time of L1. If the battery pack provides electric energy for the PFC circuit, the PFC circuit can be adopted to respectively charge the C1 and the C2, and the charging quantity of the C1 and the C2 can be adjusted by adjusting the energy storage time of the L1. C1 and C2 can also be charged simultaneously through the PFC circuit until the minimum charging amount of C1 and C2 demands is charged, and then the capacitor which is respectively charged for C1 and C2 and does not meet the requirement of the charging amount at that time is additionally charged until the charging amounts of C1 and C2 both meet the requirement of the electric equipment on the electric quantity. Because when charging for C1 and C2, PFC circuit can be through adjusting on off state control charge mode, can realize C1 and C2 to the demand of charging amount, need not to set up extra device and carry out the electric energy adjustment, and its charge efficiency is high, and owing to need not to set up extra device, has reduced UPS's cost and has promoted UPS's efficiency.

Based on the same inventive concept, the embodiment of the present application further provides a power supply system, which includes the foregoing UPS300 and an electric device.

The power consumption device may be connected to an output terminal of an inverter circuit in the UPS 300.

Specifically, the power supply device is connected between an alternating current power supply and the electric equipment, and the power supply device is used for supplying power to the electric equipment through alternating current output by the alternating current power supply.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present application without departing from the scope of the application. Thus, if such modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is intended to include such modifications and variations as well.

Claims

1. An Uninterruptible Power Supply (UPS), comprising: the Power Factor Correction (PFC) circuit, the inverter circuit, the battery pack, the positive bus and the negative bus;

the input end of the PFC circuit is connected with the battery pack, the output end of the PFC circuit is respectively connected with the positive bus and the negative bus, and the PFC circuit is used for receiving the voltage output by the battery pack through the input end of the PFC circuit, converting the voltage output by the battery pack into a first voltage and outputting the first voltage to one or both of the positive bus and the negative bus;

the input end of the inverter circuit is connected with the positive bus and the negative bus, and the inverter circuit is used for converting the voltages on the positive bus and the negative bus into a second voltage and outputting the second voltage through the output end of the inverter circuit;

the battery pack is used for outputting stored electric energy to the PFC circuit when the alternating current power supply fails.

2. The UPS of claim 1, further comprising: a controller;

3. The UPS of claim 2, wherein the controller is specifically to:

determining the electric energy required by the positive bus and the electric energy required by the negative bus;

outputting the first voltage to the positive bus and the negative bus for storage;

when the electric energy stored in a first bus meets the electric energy demand, stopping outputting the first voltage for the first bus, wherein the first bus is the bus with lower electric energy demand in the positive bus and the negative bus;

and continuously outputting the first voltage to a second bus until the electric energy stored by the second bus meets the electric energy requirement, wherein the second bus is the bus with higher electric energy requirement in the positive bus and the negative bus.

4. The UPS of claim 2, wherein the controller is specifically to:

outputting the first voltage to the third bus, the third bus being one of the positive bus and the negative bus;

when the electric energy stored by the third bus meets the electric energy demand, stopping outputting the first voltage for the third bus;

outputting the first voltage to a fourth bus bar that is the other of the positive bus bar and the negative bus bar except for the third bus bar;

and when the electric energy stored by the fourth bus meets the electric energy requirement, stopping outputting the first voltage for the fourth bus.

5. The UPS of any one of claims 1-4, wherein the PFC circuit comprises: the first inductor, the first switch, the second switch, the third switch, the fourth switch and the fifth switch;

a first end of the first inductor is connected with the alternating current power supply or the battery pack, and a second end of the first inductor is connected with a first electrode of the first switch and a second electrode of the second switch;

the second electrode of the first switch is connected with the first end of the positive bus;

the first electrode of the second switch is connected with the second end of the negative bus;

a first electrode of the third switch is connected with a second end of the first inductor, and a second electrode of the third switch is respectively connected with a first electrode of the fourth switch, the battery pack and a second end of the negative bus;

a second electrode of the fourth switch is connected with a second end of the positive bus and a first end of the negative bus;

and a first electrode of the fifth switch is connected with a second electrode of the third switch, and a second electrode of the fifth switch is connected with a second end of the negative bus.

6. The UPS of claim 5, wherein the PFC circuit further comprises: a sixth switch;

the second electrode of the third switch is connected with the first electrode of the fifth switch and the battery pack through the sixth switch.

7. The UPS of any one of claims 1-4, wherein if the AC power source outputs three-phase AC power, the PFC circuit comprises: a single-phase PFC module corresponding to each phase of alternating current in the three-phase alternating current;

8. The UPS of claim 7, wherein each of the single-phase PFC modules comprises: a second inductor, a seventh switch, an eighth switch, a ninth switch, a tenth switch, and an eleventh switch;

a first end of the second inductor is connected with the battery pack, a second end of the second inductor is connected with a first electrode of the seventh switch and a second electrode of the eighth switch, and the first end of the second inductor is used for receiving corresponding one-phase alternating current;

a second electrode of the seventh switch is connected with a first end of the positive bus;

a first electrode of the eighth switch is connected with a second end of the negative bus;

a first electrode of the ninth switch is connected with a second end of the second inductor, and a second electrode of the ninth switch is respectively connected with a first electrode of the tenth switch, a second end of the negative bus and the battery pack;

a second electrode of the tenth switch is connected to a second end of the positive bus bar and a first end of the negative bus bar;

a first electrode of the eleventh switch is connected to a second electrode of the ninth switch, and a second electrode of the eleventh switch is connected to a second end of the negative bus bar.

9. The UPS of claim 8, wherein the single-phase PFC module further comprises: a twelfth switch;

the second electrode of the ninth switch is connected with the battery pack and the first electrode of the eleventh switch through the twelfth switch.

10. A power supply system, characterized in that the power supply system comprises a consumer and an uninterruptible power supply UPS according to any of claims 1 to 9;