Uninterruptible power supplying method and uninterruptible power supply

An uninterruptible power supplying method and an uninterruptible power supply. The method includes switching an uninterruptible power supply to a bypass working mode from a main loop working mode, so as to provide mains power for a load through a bypass; determining the working mode of the uninterruptible power supply; and when the uninterruptible power supply is in the bypass working mode, adjusting a working frequency of at least one switch tube in a main loop of the uninterruptible power supply to a second frequency from a first frequency, where the second frequency is less than the first frequency, so as to reduce power loss when the uninterruptible power supply is in the bypass working mode.

TECHNICAL FIELD

The present invention relates to the field of power supply technologies, and in particular, to an uninterruptible power supplying method and an uninterruptible power supply (UPS).

BACKGROUND

In addition to a function of uninterruptedly supplying power to a user, a UPS also has functions of improving power quality and providing high power quality. The UPS generally uses a double-conversion working mode. When the UPS works, the UPS needs to consume electric energy, and greater output power of the UPS indicates more consumed electric energy. For the purpose of energy saving, when the quality of a power grid is good, a concept of working in an economical operation mode (ECO-mode) is proposed, that is, the power grid provides mains power for a load of a user directly through a bypass line (also referred to as a static bypass) of the UPS, while a main part of the UPS is in a standby state, its output power is zero, consumed electric energy is low, and therefore the efficiency of the entire system is high.

In the ECO mode, although the main part of the UPS is in the standby state, certain energy is still consumed, which hinders an effective improvement on the efficiency of the entire system in the ECO mode.

SUMMARY

Embodiments of the present invention provide an uninterruptible power supplying method and an uninterruptible power supply, which can effectively improve efficiency when the uninterruptible power supply provides power for a load directly through a bypass of the UPS at a power grid.

A first aspect provides an uninterruptible power supplying method, including switching an uninterruptible power supply to a bypass working mode from a main loop working mode, so as to provide mains power for a load through a bypass; determining the working mode of the uninterruptible power supply; and when the uninterruptible power supply is in the bypass working mode, adjusting a working frequency of at least one switch tube in a main loop of the uninterruptible power supply to a second frequency from a first frequency, where the second frequency is less than the first frequency, so as to reduce power loss when the uninterruptible power supply is in the bypass working mode.

With reference to the first aspect, in a first possible implementation manner, the adjusting a working frequency of at least one switch tube in a main loop of the uninterruptible power supply to a second frequency from a first frequency includes adjusting the working frequency of any one or more switch tubes in one or more circuits of a rectifier circuit, a discharging circuit, an auxiliary power supply, a charging circuit, and an inverter circuit in the main loop to the second frequency from the first frequency.

With reference to the first possible implementation manner, in a second possible implementation manner, the method according to the first aspect further includes, when the uninterruptible power supply is switched to the bypass working mode from the main loop working mode and a voltage of a bus bar of the uninterruptible power supply is higher than a first threshold, stopping the rectifier circuit from working, and when the voltage of the bus bar is lower than a second threshold, enabling the rectifier circuit to work, where the rectifier circuit provides electric energy for the bus bar of the uninterruptible power supply, the inverter circuit extracts the electric energy from the bus bar (BUS), the first threshold is greater than the second threshold, and the first threshold and the second threshold are respectively an upper limit value and a lower limit value of a working voltage of the bus bar, or the first threshold and the second threshold are within a range of the working voltage of the bus bar; or, when the uninterruptible power supply is switched to the bypass working mode from the main loop working mode and a voltage of a bus bar of the uninterruptible power supply is higher than a first threshold, stopping the discharging circuit from working, and when the voltage of the bus bar is lower than a second threshold, enabling the discharging circuit to work, where the discharging circuit provides electric energy for the bus bar of the uninterruptible power supply, the inverter circuit extracts the electric energy from the bus bar, the first threshold is greater than the second threshold, and the first threshold and the second threshold are respectively, an upper limit value and a lower limit value of a working voltage of the bus bar, or the first threshold and the second threshold are within a range of the working voltage of the bus bar.

With reference to the first or second possible implementation manner, in a third possible implementation manner, the method according to the first aspect further includes determining an output voltage of a charger in the main loop; and when the uninterruptible power supply is switched to the bypass working mode from the main loop working mode and the output voltage of the charger in the main loop is higher than a third threshold, stopping the charger from providing power for the auxiliary power supply, and when the output voltage of the charger is lower than a fourth threshold, providing power for the auxiliary power supply again, where the charger provides power for the auxiliary power supply, the third threshold is greater than the fourth threshold, and the third threshold and the fourth threshold are respectively an upper limit value and a lower limit value of a working voltage of the auxiliary power supply, or the third threshold and the fourth threshold are within a range of the working voltage of the auxiliary power supply.

With reference to any one of the foregoing possible implementation manners, in a fourth possible implementation manner, the method according to the first aspect further includes, when the uninterruptible power supply is switched to the bypass working mode from the main loop working mode, stopping at least one rectifier branch of multiple rectifier branches in the main loop from working, or stopping at least one discharging branch of multiple discharging branches in the main loop from working.

With reference to the first aspect or any one of the foregoing possible implementation manners, in a fifth possible implementation manner, the method according to the first aspect further includes, when the uninterruptible power supply is switched to the bypass working mode from the main loop working mode, stopping applying a drive signal to a switch tube of the inverter circuit, so as to stop the inverter circuit from working; and when the bypass is abnormal, providing the drive signal for the switch tube of the inverter circuit, so as to enable the inverter circuit to work.

A second aspect provides an uninterruptible power supplying method, including switching an uninterruptible power supply to a bypass working mode from a main loop working mode, so as to provide mains power for a load through a bypass; determining the working mode of the uninterruptible power supply; and when the uninterruptible power supply is switched to the bypass working mode from the main loop working mode and a voltage of a bus bar of the uninterruptible power supply is higher than a first threshold, stopping a rectifier circuit and/or a discharging circuit in a main loop from working, and when it is determined that the voltage of the bus bar in the main loop is lower than a second threshold, enabling the rectifier circuit and/or the discharging circuit to work, where the first threshold is greater than the second threshold, and the first threshold and the second threshold are respectively an upper limit value and a lower limit value of a working voltage of the bus bar, or the first threshold and the second threshold are within a range of the working voltage of the bus bar.

In a first possible implementation manner, the method according to the second aspect further includes determining an output voltage of a charger in the main loop; and when the uninterruptible power supply is switched to the bypass working mode from the main loop working mode and the output voltage of the charger in the main loop is higher than a third threshold, stopping the charger from providing power for an auxiliary power supply, and when the output voltage of the charger is lower than a fourth threshold, providing power for the auxiliary power supply again, where the charger provides power for the auxiliary power supply, the third threshold is greater than the fourth threshold, and the third threshold and the fourth threshold are respectively an upper limit value and a lower limit value of a working voltage of the auxiliary power supply, or the third threshold and the fourth threshold are within a range of the working voltage of the auxiliary power supply.

A third aspect provides an uninterruptible power supplying method, including switching an uninterruptible power supply to a bypass working mode from a main loop working mode, so as to provide mains power for a load through a bypass; determining the working mode of the uninterruptible power supply; and when the uninterruptible power supply is switched to the bypass working mode from the main loop working mode, stopping at least one rectifier branch of multiple rectifier branches in a main loop from working, or stopping at least one discharging branch of multiple discharging branches in a main loop from working.

In a first possible implementation manner, the method according to the third aspect further includes, when the uninterruptible power supply is switched to the bypass working mode from the main loop working mode, stopping applying a drive signal to a switch tube of an inverter circuit, so as to stop the inverter circuit from working; and when the bypass is abnormal, providing the drive signal for the switch tube of the inverter circuit, so as to enable the inverter circuit to work.

A fourth aspect provides an uninterruptible power supply, including a main loop, including a rectifier circuit, an inverter circuit, an auxiliary power supply, and a charging circuit; a bypass configured to directly provide mains power for a load; and a control module configured to switch the uninterruptible power supply to a bypass working mode from a main loop working mode so as to provide the mains power for the load through the bypass, determine the working mode of the uninterruptible power supply, and when the uninterruptible power supply is in the bypass working mode, adjust a working frequency of at least one switch tube in the main loop of the uninterruptible power supply to a second frequency from a first frequency, where the second frequency is less than the first frequency, so as to reduce power loss when the uninterruptible power supply is in the bypass working mode.

With reference to the fourth aspect, in a first possible implementation manner, the control module adjusts the working frequency of any one or more switch tubes in one or more circuits of the rectifier circuit, a discharging circuit, the auxiliary power supply, the charging circuit, and the inverter circuit to the second frequency from the first frequency.

With reference to the first possible implementation manner, in a second possible implementation manner, the main loop further includes a bus bar. When the uninterruptible power supply is switched to the bypass working mode from the main loop working mode and a voltage of the bus bar of the uninterruptible power supply is higher than a first threshold, the control module stops the rectifier circuit from working, and when the voltage of the bus bar is lower than a second threshold, the control module enables the rectifier circuit to work, where the rectifier circuit provides electric energy for the bus bar of the uninterruptible power supply, the inverter circuit extracts the electric energy from the bus bar, the first threshold is greater than the second threshold, and the first threshold and the second threshold are respectively an upper limit value and a lower limit value of a working voltage of the bus bar, or the first threshold and the second threshold are within a range of the working voltage of the bus bar; or, when the uninterruptible power supply is switched to the bypass working mode from the main loop working mode and a voltage of the bus bar of the uninterruptible power supply is higher than a first threshold, the control module stops the discharging circuit from working, and when the voltage of the bus bar is lower than a second threshold, the control module enables the discharging circuit to work, where the discharging circuit provides electric energy for the bus bar of the uninterruptible power supply, the inverter circuit extracts the electric energy from the bus bar, the first threshold is greater than the second threshold, and the first threshold and the second threshold are respectively an upper limit value and a lower limit value of a working voltage of the bus bar, or the first threshold and the second threshold are within a range of the working voltage of the bus bar.

With reference to the first or second possible implementation manner, in a third first possible implementation manner, the main loop further includes a charger. The control module determines an output voltage of the charger in the main loop; when the uninterruptible power supply is switched to the bypass working mode from the main loop working mode and the output voltage of the charger in the main loop is higher than a third threshold, the control module stops the charger from providing power for the auxiliary power supply, and when the output voltage of the charger is lower than a fourth threshold, the control module enables the charger to provide power for the auxiliary power supply again, where the charger provides power for the auxiliary power supply, the third threshold is greater than the fourth threshold, and the third threshold and the fourth threshold are respectively an upper limit value and a lower limit value of a working voltage of the auxiliary power supply, or the third threshold and the fourth threshold are within a range of the working voltage of the auxiliary power supply.

With reference to any one of the foregoing possible implementation manners of the fourth aspect, in a fourth possible implementation manner, the main loop includes multiple rectifier branches and multiple discharging branches; when the uninterruptible power supply is switched to the bypass working mode from the main loop working mode, the control module further stops at least one rectifier branch of the multiple rectifier branches in the main loop from working, or stops at least one discharging branch of the multiple discharging branches in the main loop from working.

With reference to any one of the foregoing possible implementation manners of the fourth aspect, in a fifth possible implementation manner, when the uninterruptible power supply is switched to the bypass working mode from the main loop working mode, the control module further stops applying a drive signal to a switch tube of the inverter circuit, so as to stop the inverter circuit from working; when the bypass is abnormal, the control module provides the drive signal for the switch tube of the inverter circuit, so as to enable the inverter circuit to work.

A fifth aspect provides an uninterruptible power supply, including a main loop, including a rectifier circuit, a discharging circuit, a bus bar, and an inverter circuit, where the rectifier circuit provides electric energy for the bus bar, and the inverter circuit extracts the electric energy from the bus bar; a bypass configured to directly provide mains power for a load; and a control module configured to switch the uninterruptible power supply to a bypass working mode from a main loop working mode so as to provide the mains power for the load through the bypass, determine the working mode of the uninterruptible power supply, and when the uninterruptible power supply is switched to the bypass working mode from the main loop working mode and a voltage of the bus bar of the uninterruptible power supply is higher than a first threshold, stop the rectifier circuit and/or the discharging circuit in the main loop from working, and when it is determined that the voltage of the bus bar in the main loop is lower than a second threshold, enable the rectifier circuit and/or the discharging circuit to work, where the first threshold is greater than the second threshold, and the first threshold and the second threshold are respectively an upper limit value and a lower limit value of a working voltage of the bus bar, or the first threshold and the second threshold are within a range of the working voltage of the bus bar.

With reference to the fifth aspect, in a first possible implementation manner, the main loop further includes a charger and an auxiliary power supply, where the charger of the uninterruptible power supply provides power for the auxiliary power supply of the uninterruptible power supply. The control module is further configured to determine an output voltage of the charger in the main loop; and when the uninterruptible power supply is switched to the bypass working mode from the main loop working mode and the output voltage of the charger in the main loop is higher than a third threshold, stop the charger from providing power for the auxiliary power supply, and when the output voltage of the charger is lower than a fourth threshold, provide power for the auxiliary power supply again, where the charger provides power for the auxiliary power supply, the third threshold is greater than the fourth threshold, and the third threshold and the fourth threshold are respectively an upper limit value and a lower limit value of a working voltage of the auxiliary power supply, or the third threshold and the fourth threshold are within a range of the working voltage of the auxiliary power supply.

A sixth aspect provides an uninterruptible power supply, including a main loop, including multiple rectifier branches and multiple discharging branches; a bypass configured to directly provide mains power a load; and a control module configured to switch the uninterruptible power supply to a bypass working mode from a main loop working mode, so as to provide the mains power for the load through the bypass, determine the working mode of the uninterruptible power supply, and when the uninterruptible power supply is switched to the bypass working mode from the main loop working mode, stop at least one rectifier branch of the multiple rectifier branches in the main loop from working, or stop at least one discharging branch of the multiple discharging branches in the main loop from working.

With reference to the sixth aspect, in a first possible implementation manner, the main loop further includes an inverter circuit. When the uninterruptible power supply is switched to the bypass working mode from the main loop working mode, the control module further stops applying a drive signal to a switch tube of the inverter circuit, so as to stop the inverter circuit from working; when the bypass is abnormal, the control module provides the drive signal for the switch tube of the inverter circuit, so as to enable the inverter circuit to work.

According to the embodiments of the present invention, when an uninterruptible power supply is switched to run in a bypass working mode, a working frequency of a switch tube in a main loop of the uninterruptible power supply can decrease, thereby reducing working loss of the uninterruptible power supply and effectively improving working efficiency of the uninterruptible power supply.

DESCRIPTION OF EMBODIMENTS

A UPS can provide electric energy for a load in an online mode and an ECO mode according to mains power quality. For example, the online mode is used in a case in which the mains power quality is not good, and the ECO mode is used in a case in which the mains power quality is good. The ECO mode is also referred to as an energy-saving running mode, a bypass mode, or a power saving mode. The UPS can provide power for the load using two passages, an online main loop (also referred to as a double-conversion loop) and a bypass. When the online mode is used, if the mains power is normal, the online main loop formed by a rectifier and an inverter provides power for the load, and if the mains power fails, a discharging loop formed by a battery and an inverter of the UPS provides power for the load. When the ECO mode is used, the online main loop of the UPS is in a standby state, the bypass is in an active state, and the mains power is provided for the load. The UPS can continuously monitor mains input; in a case in which the mains power quality is good, the UPS is switched to run in a bypass working mode, and when the mains power quality decreases to a certain degree, switching is performed so that the inverter of the UPS provides electric energy for the load. Herein, the mains power may refer to alternating current provided by a power grid, and the embodiments of the present invention are not limited thereto; the mains power may refer to a power supply whose voltage, waveform, frequency, grounding system, and impedance are the same as or similar to those of alternating current provided by the online main loop.

For the convenience of describing uninterruptible power supplying methods in the embodiments of the present invention, the following first describes the structure and a working principle of a specific UPS.

FIG. 1is a schematic structural diagram of an uninterruptible power supply100. The uninterruptible power supply100includes a main loop110and a bypass120. The main loop110includes a rectifier circuit111, a bus bar112, an inverter circuit113, a direct current to direct current (DC/DC) circuit114, a battery115, a charger116, and an auxiliary power supply117.

When the uninterruptible power supply100uses an online mode, the rectifier circuit111may convert input mains power into a direct current by means of rectification and apply the mains power to the bus bar112; then, the inverter113converts a voltage of the bus bar112into an alternating current voltage by means of inversion and provides power for a load. When the uninterruptible power supply100uses an ECO mode, the bypass120is used for the bypass of the uninterruptible power supply, that is the bypass120is configured to directly provide mains power for the load, that is, when the uninterruptible power supply100uses the ECO mode, the mains power is directly provided for the load through the bypass120, so that the uninterruptible power supply is switched to run in a bypass working mode, that is, the mains power is directly provided for the load. The charger116is configured to charge the battery115, and may be powered by the bus bar112or the mains power. The auxiliary power supply117is configured to provide a working power supply for each part of the uninterruptible power supply100, and may be powered by the bus bar112, the mains power, and/or the charger116. When the uninterruptible power supply100uses the online mode, if the mains power fails, an output of the battery115may be applied to the bus bar112through the direct current to direct current (DC/DC) circuit114(a discharging circuit), thereby ensuring that power is supplied to the load uninterruptedly. Generally, the charger116is stopped. Energy of the bus bar112is provided by the battery115. If the charger works, energy goes to the battery115from the bus bar112through the charger116, and then goes to the bus bar112from the battery115through the DC/DC circuit114. In a special case, the bus bar112may extract electricity from the bypass120through the inverter circuit113; in this way, the charger116can work and charge the battery115.

The uninterruptible power supply inFIG. 1is a specific embodiment of the present invention, and a person skilled in the art should understand that the uninterruptible power supply may include only some of the foregoing components. For example, in another embodiment of the present invention, the uninterruptible power supply may not include the rectifier circuit111or the DC/DC circuit114.

FIG. 2is a schematic flowchart of an uninterruptible power supplying method according to an embodiment of the present invention.

210: Switch an uninterruptible power supply to a bypass working mode from a main loop working mode, so as to provide mains power for a load through a bypass.

When the uninterruptible power supply is working, the uninterruptible power supply is generally in the main loop working mode, and it may be switched to the bypass working mode in some cases. According to this embodiment of the present invention, the uninterruptible power supply may be manually switched to run in the bypass working mode. For example, when a user expects the uninterruptible power supply to use an ECO mode, the user may manually switch, using a manual button on the uninterruptible power supply, the uninterruptible power supply to run in the bypass working mode. Optionally, as another embodiment, mains power quality may be first checked, and then the uninterruptible power supply is switched to run in the bypass working mode according to a check result. For example, a dedicated check module may be arranged on the uninterruptible power supply to check the mains power quality; when the mains power quality is good, a control module switches the uninterruptible power supply to the bypass from a main loop, that is, the uninterruptible power supply runs in the ECO mode; when the mains power quality is not good, the control module switches the uninterruptible power supply to the main loop from the bypass, so that an inverter of the uninterruptible power supply provides power for the load, that is, the uninterruptible power supply runs in an online mode.

220: Determine the working mode of the uninterruptible power supply.

For example, the uninterruptible power supply may determine, according to a manual input of the user or according to the foregoing check result, whether the uninterruptible power supply is in the bypass working mode or the main loop working mode.

230: When the uninterruptible power supply is in the bypass working mode, adjust a working frequency of at least one switch tube in a main loop of the uninterruptible power supply to a second frequency from a first frequency, where the second frequency is less than the first frequency, so as to reduce power loss when the uninterruptible power supply is in the bypass working mode.

For example, when the uninterruptible power supply is switched to run in the bypass working mode and enters the ECO mode, a controller or the control module of the uninterruptible power supply may change the working frequency of the switch tube in a main circuit of the uninterruptible power supply.

According to this embodiment of the present invention, when an uninterruptible power supply is switched to run in a bypass working mode, a working frequency of a switch tube in a main loop of the uninterruptible power supply can decrease, thereby reducing working loss of the uninterruptible power supply and effectively improving working efficiency of the uninterruptible power supply.

In230, the working frequency of any one or more switch tubes in one or more circuits of a rectifier circuit, a discharging circuit, an auxiliary power supply, a charging circuit, and an inverter circuit in the main loop may be adjusted to the second frequency from the first frequency.

According to this embodiment of the present invention, when the uninterruptible power supply is switched to run in the bypass working mode, the working frequency of any one or more switch tubes (for example, a main switch tube) in the rectifier circuit, the discharging circuit, the auxiliary power supply, and the inverter circuit of the uninterruptible power supply can decrease, thereby reducing loss of the rectifier circuit, the inverter circuit, the auxiliary power supply, or the discharging circuit of the uninterruptible power supply and improving efficiency of the entire system of the uninterruptible power supply.

For example, the rectifier circuit may convert energy of input mains power into a direct current and send the direct current to a bus bar. In the ECO mode, the inverter circuit does not output power, and the rectifier circuit needs to provide only little energy for the bus bar; therefore, a working frequency of a switch tube of the rectifier circuit can be reduced when it is ensured that a voltage of the bus bar fluctuates in a reliable range, thereby reducing working loss of the rectifier circuit. In addition, in a case in which a charger extracts electricity from the bus bar and charges a battery and the auxiliary power supply extracts electric energy from the bus bar, the energy demanded by the charger and the auxiliary power supply is much smaller when compared with output power of the entire system; therefore, even if a working frequency of the rectifier circuit is reduced, the demand of the entire system for power supplying can still be met. In the ECO mode, the inverter circuit is in a standby state and does not output power. Therefore, a working frequency of a switch tube of the inverter circuit can also be reduced, and working loss of the inverter circuit is reduced while quality of output electric energy is ensured.

In the ECO mode, multiple parts of the uninterruptible power supply are in the standby state or a low-speed running state, particularly a fan. The fan generally rotates at a low speed or stops rotating. Therefore, output power of the auxiliary power supply (auxiliary source) can be reduced, so that a working frequency of a switch tube of the auxiliary power supply can also be reduced, thereby reducing working loss of the auxiliary power supply. In this case, a working current of the entire system is very small, and a reduction in the working frequency has little impact on noise and waveform quality; therefore, working of the entire system is not affected.

Optionally, as another embodiment, the method inFIG. 2further includes, when the uninterruptible power supply is switched to the bypass working mode from the main loop working mode and the voltage of the bus bar of the uninterruptible power supply is higher than a first threshold, stopping the rectifier circuit from working; and when the voltage of the bus bar is lower than a second threshold, enabling the rectifier circuit to work, where the rectifier circuit provides electric energy for the bus bar of the uninterruptible power supply, the inverter circuit extracts the electric energy from the bus bar, the first threshold is greater than the second threshold, and the first threshold and the second threshold are respectively an upper limit value and a lower limit value of a working voltage of the bus bar, or the first threshold and the second threshold are within a range of the working voltage of the bus bar.

Optionally, as another embodiment, the method inFIG. 2further includes, when the uninterruptible power supply is switched to the bypass working mode from the main loop working mode and the voltage of the bus bar of the uninterruptible power supply is higher than a first threshold, stopping the discharging circuit from working; and when the voltage of the bus bar is lower than a second threshold, enabling the discharging circuit to work, where the discharging circuit provides electric energy for the bus bar of the uninterruptible power supply, the inverter circuit extracts the electric energy from the bus bar, the first threshold is greater than the second threshold, and the first threshold and the second threshold are respectively an upper limit value and a lower limit value of a working voltage of the bus bar, or the first threshold and the second threshold are within a range of the working voltage of the bus bar.

For the rectifier circuit, in the ECO mode, each part of the uninterruptible power supply extracts very little energy from the bus bar; therefore, even though the rectifier circuit does not supplement energy for the bus bar, energy stored on the bus bar can ensure that each part that extracts electric energy from the bus bar can work normally for quite a long time. This embodiment of the present invention provides a voltage hysteresis method. The rectifier circuit first raises the energy (or the voltage) of the bus bar to a set threshold (for example, the first threshold) in a period, and then the rectifier circuit stops working; in this case, the energy stored on the bus bar is provided for each part. The voltage of the bus bar decreases slowly, and when the voltage of the bus bar decreases to a set threshold (for example, the second threshold), the rectifier circuit begins to work again, provides energy for the bus bar, and raises the voltage of the bus bar to the first threshold. This process repeats to ensure normal running of the entire system. In this working manner, the rectifier circuit works intermittently and does not work in quite a long time; therefore, the loss can be reduced.

Optionally, as another embodiment, the method inFIG. 2further includes determining an output voltage of the charger in the main loop; and when the uninterruptible power supply is switched to the bypass working mode from the main loop working mode and the output voltage of the charger in the main loop is higher than a third threshold, stopping the charger from providing power for the auxiliary power supply, and when the output voltage of the charger is lower than a fourth threshold, providing power for the auxiliary power supply again, where the charger provides power for the auxiliary power supply, the third threshold is greater than the fourth threshold, and the third threshold and the fourth threshold are respectively an upper limit value and a lower limit value of a working voltage of the auxiliary power supply, or the third threshold and the fourth threshold are within a range of the working voltage of the auxiliary power supply.

For a circuit structure in which the auxiliary power supply extracts electric energy from the charger, the energy demanded by the auxiliary power supply is also small in the ECO mode; therefore, the charger may also provide power for the auxiliary power supply when working in a voltage hysteresis manner, thereby reducing the loss of the charger.

Optionally, as another embodiment, the method inFIG. 2further includes, when the uninterruptible power supply is switched to the bypass working mode from the main loop working mode, stopping at least one rectifier branch of multiple rectifier branches in the main loop from working, or stopping at least one discharging branch of multiple discharging branches in the main loop from working.

A switch tube in the rectifier branch/the discharging branch may be stopped from working, so as to stop the rectifier branch/the discharging branch from working, or electric energy may be stopped from being input to the rectifier/discharging branch, so as to stop the rectifier/discharging branch from working.

For the rectifier circuit, in a case in which the rectifier circuit of the uninterruptible power supply includes two or more rectifier branches, the bus bar needs little energy in the ECO mode; therefore, some of the rectifier branches may be closed, and some of the rectifier branches may be kept working, for example, only one rectifier branch is kept working to provide energy for the bus bar. Because some of the rectifier branches stop working, the loss of the uninterruptible power supply can be reduced.

For the discharging circuit, in a case in which the discharging circuit of the uninterruptible power supply includes two or more discharging branches, the bus bar needs little energy in the ECO mode; therefore, some of the discharging branches may be closed, and some of the discharging branches may be kept working, for example, only one discharging branch is kept working to provide energy for the bus bar. Because some of the discharging branches stop working, the loss of the uninterruptible power supply can be reduced.

Optionally, as another embodiment, the methodFIG. 2further includes, when the uninterruptible power supply is switched to the bypass working mode from the main loop working mode, stopping applying a drive signal to a switch tube of the inverter circuit, so as to stop the inverter circuit from working; and when the bypass is abnormal, providing the drive signal for the switch tube of the inverter circuit, so as to enable the inverter circuit to work. For example, the drive signal of the inverter circuit may be turned off, or the drive signal of the inverter circuit may be kept in a low level.

If the time from the moment when the inverter circuit is started from a turned-off state to the moment when the inverter circuit can provide electric energy for the user meets the requirement of reliably providing power for the load, that is, if the inverter circuit can be started in time and provide power for the load in a case in which the bypass is abnormal and cannot continue to reliably provide electric energy for the load, the inverter may be turned off in the ECO mode, thereby reducing the loss.

FIG. 3is a schematic flowchart of an uninterruptible power supplying method according to another embodiment of the present invention.

310: Switch an uninterruptible power supply to a bypass working mode from a main loop working mode, so as to provide mains power for a load through a bypass; and determine the working mode of the uninterruptible power supply. This is similar to step210in the embodiment inFIG. 2, and details are not described herein again.

320: Determine the working mode of the uninterruptible power supply. This is similar to step220in the embodiment inFIG. 2, and details are not described herein again.

330: When the uninterruptible power supply is switched to the bypass working mode from the main loop working mode and a voltage of a bus bar of the uninterruptible power supply is higher than a first threshold, stop a rectifier circuit and/or a discharging circuit in a main loop from working; when it is determined that the voltage of the bus bar in the main loop is lower than a second threshold, enable the rectifier circuit and/or the discharging circuit to work, where the first threshold is greater than the second threshold, and the first threshold and the second threshold are respectively an upper limit value and a lower limit value of a working voltage of the bus bar, or the first threshold and the second threshold are within a range of the working voltage of the bus bar.

For the rectifier circuit, in an ECO mode, each part of the uninterruptible power supply extracts very little energy from the bus bar; therefore, even though the rectifier circuit does not supplement energy for the bus bar, energy stored on the bus bar can ensure that each part that extracts electric energy from the bus bar can work normally for quite a long time. This embodiment of the present invention provides a voltage hysteresis method. The rectifier circuit first raises the energy (or the voltage) of the bus bar to a set threshold (for example, the first threshold) in a period, and then the rectifier circuit stops working; in this case, the energy stored on the bus bar is provided for each part. The voltage of the bus bar decreases slowly, and when the voltage of the bus bar decreases to a set threshold (for example, the second threshold), the rectifier circuit begins to work again, provides energy for the bus bar, and raises the voltage of the bus bar to the first threshold. This process repeats to ensure normal running of the entire system. In this working manner, the rectifier circuit works intermittently and does not work in quite a long time; therefore, the loss can be reduced.

According to this embodiment of the present invention, when an uninterruptible power supply is switched to run in a bypass working mode, in a case in which it is determined that a voltage of a bus bar of the uninterruptible power supply is higher than a first threshold, a rectifier circuit and/or a discharging circuit is stopped from working; in a case in which it is determined that the voltage of the bus bar is lower than a second threshold, the rectifier circuit and/or the discharging circuit is enabled to work, thereby reducing working loss of the uninterruptible power supply and effectively improving working efficiency of the uninterruptible power supply.

Optionally, as another embodiment, the method inFIG. 3further includes determining an output voltage of a charger in the main loop; and when the uninterruptible power supply is switched to the bypass working mode from the main loop working mode and the output voltage of the charger in the main loop is higher than a third threshold, stopping the charger from providing power for an auxiliary power supply, and when the output voltage of the charger is lower than a fourth threshold, providing power for the auxiliary power supply again, where the charger provides power for the auxiliary power supply, the third threshold is greater than the fourth threshold, and the third threshold and the fourth threshold are respectively an upper limit value and a lower limit value of a working voltage of the auxiliary power supply, or the third threshold and the fourth threshold are within a range of the working voltage of the auxiliary power supply.

For a circuit structure in which the auxiliary power supply extracts electric energy from the charger, the energy demanded by the auxiliary power supply is also small in the ECO mode; therefore, the charger may also provide power for the auxiliary power supply when working in a voltage hysteresis manner, thereby reducing loss of the charger.

FIG. 4is a schematic diagram of a voltage hysteresis method according to an embodiment of the present invention.

Referring toFIG. 4, when a voltage of a bus bar is lower than a second threshold, a drive circuit of a rectifier circuit generates a drive signal (a drive waveform as shown inFIG. 4), so that the rectifier circuit works and provides electric energy for the bus bar, and the voltage of the bus bar rises; when the voltage of the bus bar is higher than a first threshold, the drive circuit of the rectifier circuit stops generating the drive signal, so that the rectifier circuit stops working and no longer provides the electric energy for the bus bar, and the voltage of the bus bar decreases because the electric energy is extracted by an inverter circuit; when the voltage of the bus bar decreases to the second threshold, the drive circuit of the rectifier circuit re-generates the drive signal, so that the voltage of the bus bar is kept between the first threshold and the second threshold. It should be understood that, the first threshold and the second threshold may be set by a person of ordinary skill in the art according to needs, as long as the voltage of the bus bar can ensure that each part that extracts electric energy from the bus bar can work normally.

Similarly, for a voltage hysteresis method of a charger, when an output voltage of the charger is lower than a fourth threshold, a drive signal is generated, so that the charger provides electric energy for an auxiliary power supply, and the output voltage of the charger rises; when the output voltage of the charger is higher than a third threshold, the charger stops providing the electric energy for the auxiliary power supply, so that the output voltage of the charger decreases; when the output voltage of the charger decreases to the fourth threshold, the drive signal is generated again, so that the charger provides the electric energy for the auxiliary power supply again and a voltage provided by the charger for the auxiliary power supply is kept between the third threshold and the fourth threshold. It should be understood that, the third threshold and the fourth threshold may be set by a person of ordinary skill in the art according to needs, as long as the voltage provided for the auxiliary power supply can ensure that each part that extracts electric energy from the auxiliary power supply can work normally.

FIG. 5is a schematic flowchart of an uninterruptible power supplying method according to another embodiment of the present invention.

510: Switch an uninterruptible power supply to a bypass working mode from a main loop working mode, so as to provide mains power for a load through a bypass. This is similar to step210inFIG. 2, and details are not described herein again.

520: Determine the working mode of the uninterruptible power supply. This is similar to step220inFIG. 2, and details are not described herein again.

530: When the uninterruptible power supply is switched to the bypass working mode from the main loop working mode, stop at least one rectifier branch of multiple rectifier branches in a main loop from working, or stop at least one discharging branch of multiple discharging branches in a main loop from working.

For a rectifier circuit, in a case in which the rectifier circuit of the uninterruptible power supply includes two or more rectifier branches, a bus bar needs little energy in an ECO mode; therefore, some of the rectifier branches may be closed, and some of the rectifier branches may be kept working, for example, only one rectifier branch is kept working to provide energy for the bus bar. Because some of the rectifier branches stop working, loss of the uninterruptible power supply can be reduced.

For a discharging circuit, in a case in which the discharging circuit of the uninterruptible power supply includes two or more discharging branches, the bus bar needs little energy in the ECO mode; therefore, some of the discharging branches may be closed, and some of the discharging branches may be kept working, for example, only one discharging branch is kept working to provide energy for the bus bar. Because some of the discharging branches stop working, loss of the uninterruptible power supply can be reduced.

According to this embodiment of the present invention, when an uninterruptible power supply is switched to run in a bypass working mode, in a case in which it is determined that a voltage of a bus bar of the uninterruptible power supply is higher than a first threshold, at least one rectifier branch of multiple rectifier branches or at least one discharging branch of multiple discharging branches in the uninterruptible power supply is stopped from working, thereby reducing working loss of the uninterruptible power supply and effectively improving working efficiency of the uninterruptible power supply. For example, a drive signal of the rectifier branch or the discharging branch may be turned off, or the drive signal may be kept in a low level.

Optionally, as another embodiment, the method inFIG. 5further includes, when the uninterruptible power supply is switched to the bypass working mode from the main loop working mode, stopping applying a drive signal to a switch tube of an inverter circuit, so as to stop the inverter circuit from working; and when the bypass is abnormal, providing the drive signal for the switch tube of the inverter circuit, so as to enable the inverter circuit to work.

If the time from the moment when the inverter circuit is started from a turned-off state to the moment when the inverter circuit can provide electric energy for a user meets the requirement of reliably providing power for the load, that is, if the inverter circuit can be started in time and provide power for the load in a case in which the bypass is abnormal and cannot continue to reliably provide electric energy for the load, the inverter may be turned off in the ECO mode, thereby reducing the loss.

FIG. 6is a schematic circuit diagram of a rectifier circuit of an uninterruptible power supply according to an embodiment of the present invention, which is powered by two batteries in series: E1and E2.

A main loop of the uninterruptible power supply inFIG. 6includes three rectifier branches, a rectifier branch1, a rectifier branch2, and a rectifier branch3. The rectifier branch1includes diodes D11to D18, inductors L11and L12, switch tubes Q11and Q12, and capacitors C11and C12. The rectifier branch2includes diodes D21to D28, inductors L21and L22, switch tubes Q21and Q22, and capacitors C21and C22. The rectifier branch3includes diodes D31to D38, inductors L31and L32, switch tubes Q31and Q32, and capacitors C31and C32. The three-phase rectifier branches receive an input of a three-phase alternating current and applies a rectified direct current to a BUS.

The foregoing describes the uninterruptible power supplying methods according to the embodiments of the present invention, and the following describes uninterruptible power supplies according to the embodiments of the present invention separately with reference toFIG. 7toFIG. 12.

FIG. 7is a schematic structural diagram of an uninterruptible power supply700according to an embodiment of the present invention. The uninterruptible power supply700includes a main loop710, a bypass720, and a control module730.

The main loop710includes a rectifier circuit, an inverter circuit, an auxiliary power supply, and a charging circuit. The bypass720is configured to directly provide mains power for a load. The control module730is configured to switch the uninterruptible power supply700to a bypass working mode from a main loop working mode, so as to provide the mains power for the load through the bypass720; determine the working mode of the uninterruptible power supply700; and when the uninterruptible power supply700is switched to the bypass working mode from the main loop working mode and a voltage of a bus bar of the uninterruptible power supply700is higher than a first threshold, stop the rectifier circuit and/or a discharging circuit in the main loop710from working, and when it is determined that the voltage of the bus bar in the main loop710is lower than a second threshold, enable the rectifier circuit and/or the discharging circuit to work, where the first threshold is greater than the second threshold, and the first threshold and the second threshold are respectively an upper limit value and a lower limit value of a working voltage of the bus bar, or the first threshold and the second threshold are within a range of the working voltage of the bus bar.

According to this embodiment of the present invention, the control module730adjusts a working frequency of any one or more switch tubes in one or more circuits of the rectifier circuit, the discharging circuit, the auxiliary power supply, the charging circuit, and the inverter circuit to a second frequency from a first frequency.

According to this embodiment of the present invention, when an uninterruptible power supply is switched to run in a bypass working mode, a working frequency of a switch tube in a main loop of the uninterruptible power supply can decrease, thereby reducing working loss of the uninterruptible power supply and effectively improving working efficiency of the uninterruptible power supply.

Optionally, as another embodiment, the main loop710further includes a bus bar. When the uninterruptible power supply700is switched to the bypass working mode from the working mode of the main loop710and the voltage of the bus bar of the uninterruptible power supply700is higher than the first threshold, the control module730stops the rectifier circuit from working; when the voltage of the bus bar is lower than the second threshold, the control module730enables the rectifier circuit to work, where the rectifier circuit provides electric energy for the bus bar of the uninterruptible power supply700, the inverter circuit extracts the electric energy from the bus bar, the first threshold is greater than the second threshold, and the first threshold and the second threshold are respectively the upper limit value and the lower limit value of the working voltage of the bus bar, or the first threshold and the second threshold are within the range of the working voltage of the bus bar.

Optionally, as another embodiment, when the uninterruptible power supply700is switched to the working mode of the bypass720from the working mode of the main loop710and the voltage of the bus bar of the uninterruptible power supply700is higher than the first threshold, the control module730stops the discharging circuit from working; when the voltage of the bus bar is lower than the second threshold, the control module730enables the discharging circuit to work, where the discharging circuit provides electric energy for the bus bar of the uninterruptible power supply700, the inverter circuit extracts the electric energy from the bus bar, the first threshold is greater than the second threshold, and the first threshold and the second threshold are respectively the upper limit value and the lower limit value of the working voltage of the bus bar, or the first threshold and the second threshold are within the range of the working voltage of the bus bar.

Optionally, as another embodiment, the main loop710further includes a charger. The control module730determines an output voltage of the charger in the main loop710; when the uninterruptible power supply700is switched to the bypass working mode from the main loop working mode and the output voltage of the charger in the main loop710is higher than a third threshold, the control module730stops the charger from providing power for the auxiliary power supply; when the output voltage of the charger is lower than a fourth threshold, the control module730enables the charger to provide power for the auxiliary power supply again, where the charger provides power for the auxiliary power supply, the third threshold is greater than the fourth threshold, and the third threshold and the fourth threshold are respectively an upper limit value and a lower limit value of a working voltage of the auxiliary power supply, or the third threshold and the fourth threshold are within a range of the working voltage of the auxiliary power supply.

Optionally, as another embodiment, the main loop710includes multiple rectifier branches and multiple discharging branches; when the uninterruptible power supply700is switched to the bypass working mode from the main loop working mode, the control module730further stops at least one rectifier branch of the multiple rectifier branches in the main loop710from working, or stops at least one discharging branch of the multiple discharging branches in the main loop710from working.

Optionally, as another embodiment, when the uninterruptible power supply700is switched to the bypass working mode from the main loop working mode, the control module730further stops applying a drive signal to a switch tube of the inverter circuit, so as to stop the inverter circuit from working; when the bypass720is abnormal, the control module730provides the drive signal for the switch tube of the inverter circuit, so as to enable the inverter circuit to work.

For operations and functions of each unit of the uninterruptible power supply700, reference may be made to the method inFIG. 2. To avoid repetition, details are not described herein again.

FIG. 8is a schematic structural diagram of an uninterruptible power supply800according to another embodiment of the present invention. The uninterruptible power supply800includes a main loop810, a bypass820, and a control module830.

The main loop810includes a rectifier circuit, a discharging circuit, a bus bar, and an inverter circuit, where the rectifier circuit provides electric energy for the bus bar, and the inverter circuit extracts the electric energy from the bus bar. The control module830is configured to switch the uninterruptible power supply800to a bypass working mode from a main loop working mode, so as to provide mains power for a load through the bypass820; determine the working mode of the uninterruptible power supply800; and when the uninterruptible power supply800is switched to the bypass working mode from the main loop working mode and a voltage of the bus bar of the uninterruptible power supply800is higher than a first threshold, stop the rectifier circuit and/or the discharging circuit in the main loop810from working, and when it is determined that the voltage of the bus bar in the main loop810is lower than a second threshold, enable the rectifier circuit and/or the discharging circuit to work, where the first threshold is greater than the second threshold, and the first threshold and the second threshold are respectively an upper limit value and a lower limit value of a working voltage of the bus bar, or the first threshold and the second threshold are within a range of the working voltage of the bus bar.

According to this embodiment of the present invention, when an uninterruptible power supply is switched to run in a bypass working mode, in a case in which it is determined that a voltage of a bus bar of the uninterruptible power supply is higher than a first threshold, a rectifier circuit and/or a discharging circuit is stopped from working; in a case in which it is determined that the voltage of the bus bar is lower than a second threshold, the rectifier circuit and/or the discharging circuit is enabled to work, thereby reducing working loss of the uninterruptible power supply and effectively improving working efficiency of the uninterruptible power supply.

Optionally, as another embodiment, the main loop810further includes a charger and an auxiliary power supply, where the charger of the uninterruptible power supply800provides power for the auxiliary power supply of the uninterruptible power supply800. The control module830is further configured to determine an output voltage of the charger in the main loop810; and when the uninterruptible power supply800is switched to the bypass working mode from the main loop working mode and the output voltage of the charger in the main loop810is higher than a third threshold, stop the charger from providing power for the auxiliary power supply, and when the output voltage of the charger is lower than a fourth threshold, provide power for the auxiliary power supply again, where the charger provides power for the auxiliary power supply, the third threshold is greater than the fourth threshold, and the third threshold and the fourth threshold are respectively an upper limit value and a lower limit value of a working voltage of the auxiliary power supply, or the third threshold and the fourth threshold are within a range of the working voltage of the auxiliary power supply.

For operations and functions of each unit of the uninterruptible power supply800, reference may be made to the method inFIG. 5. To avoid repetition, details are not described herein again.

FIG. 9is a schematic structural diagram of an uninterruptible power supply900according to another embodiment of the present invention. The uninterruptible power supply900includes a main loop910, a bypass920, and a control module930.

The main loop910includes multiple rectifier branches and multiple discharging branches. The bypass920is configured to directly provide mains power for a load. The control module930is configured to switch the uninterruptible power supply900to a bypass working mode from a main loop working mode, so as to provide the mains power for the load through the bypass920; determine the working mode of the uninterruptible power supply900; and when the uninterruptible power supply900is switched to the bypass working mode from the main loop working mode, stop at least one rectifier branch of the multiple rectifier branches in the main loop910from working, or stop at least one discharging branch of the multiple discharging branches in the main loop910from working.

Optionally, as another embodiment, the main loop910further includes an inverter circuit. When the uninterruptible power supply900is switched to the bypass working mode from the main loop working mode, the control module930further stops applying a drive signal to a switch tube of the inverter circuit, so as to stop the inverter circuit from working; when the bypass920is abnormal, the control module930provides the drive signal for the switch tube of the inverter circuit, so as to enable the inverter circuit to work.

For operations and functions of each unit of the uninterruptible power supply900, reference may be made to the method inFIG. 5. To avoid repetition, details are not described herein again.

FIG. 10is a schematic structural diagram of an uninterruptible power supply1000according to another embodiment of the present invention. The uninterruptible power supply1000includes a processor1010, a memory1020, a main loop1030, a communication bus1040, and a bypass1050.

The processor1010invokes, using the communication bus1040, code stored in the memory1020, and is configured to switch the uninterruptible power supply1000to a bypass working mode from a main loop working mode, so as to provide mains power for a load through the bypass1050; determine the working mode of the uninterruptible power supply1000; and when the uninterruptible power supply1000is in the bypass working mode, adjust a working frequency of at least one switch tube in the main loop1030of the uninterruptible power supply1000to a second frequency from a first frequency, where the second frequency is less than the first frequency, so as to reduce power loss when the uninterruptible power supply1000is in the bypass working mode.

According to this embodiment of the present invention, when an uninterruptible power supply is switched to run in a bypass working mode, a working frequency of a switch tube in a main loop of the uninterruptible power supply can decrease, thereby reducing working loss of the uninterruptible power supply and effectively improving working efficiency of the uninterruptible power supply.

According to this embodiment of the present invention, the main loop1030includes a rectifier circuit, a discharging circuit, an auxiliary power supply, and an inverter circuit. The processor1010adjusts the working frequency of any one or more switch tubes of one or more circuits of the rectifier circuit, the discharging circuit, the auxiliary power supply, the charging circuit, and the inverter circuit to the second frequency from the first frequency.

Optionally, as another embodiment, the main loop1030further includes a bus bar. The rectifier circuit and the discharging circuit provide electric energy for the bus bar of the uninterruptible power supply1000. The inverter circuit extracts the electric energy from the bus bar. When the uninterruptible power supply1000is switched to the bypass working mode from the main loop working mode and a voltage of the bus bar of the uninterruptible power supply1000is higher than a first threshold, the processor1010stops the rectifier circuit from working; when the voltage of the bus bar is lower than a second threshold, the processor1010enables the rectifier circuit to work, where the rectifier circuit provides electric energy for the bus bar of the uninterruptible power supply1000, the inverter circuit extracts the electric energy from the bus bar, the first threshold is greater than the second threshold, and the first threshold and the second threshold are respectively an upper limit value and a lower limit value of a working voltage of the bus bar, or the first threshold and the second threshold are within a range of the working voltage of the bus bar. Alternatively, when the uninterruptible power supply1000is switched to the bypass working mode from the main loop working mode and a voltage of the bus bar of the uninterruptible power supply1000is higher than a first threshold, the processor1010stops the discharging circuit from working; when the voltage of the bus bar is lower than a second threshold, the processor1010enables the discharging circuit to work, where the discharging circuit provides electric energy for the bus bar of the uninterruptible power supply1000, the inverter circuit extracts the electric energy from the bus bar, the first threshold is greater than the second threshold, and the first threshold and the second threshold are respectively an upper limit value and a lower limit value of a working voltage of the bus bar, or the first threshold and the second threshold are within a range of the working voltage of the bus bar.

Optionally, as another embodiment, the main loop1030further includes a charger. The processor1010further determines an output voltage of the charger in the main loop1030; when the uninterruptible power supply1000is switched to the bypass working mode from the main loop working mode and the output voltage of the charger in the main loop1030is higher than a third threshold, the processor1010stops the charger from providing power for the auxiliary power supply; when the output voltage of the charger is lower than a fourth threshold, the processor1010enables the charger to provide power for the auxiliary power supply again, where the charger provides power for the auxiliary power supply, the third threshold is greater than the fourth threshold, and the third threshold and the fourth threshold are respectively an upper limit value and a lower limit value of a working voltage of the auxiliary power supply, or the third threshold and the fourth threshold are within a range of the working voltage of the auxiliary power supply.

Optionally, as another embodiment, the main loop1030includes multiple rectifier branches and multiple discharging branches; when the uninterruptible power supply1000is switched to the bypass working mode from the main loop working mode, the processor1010further stops at least one rectifier branch of the multiple rectifier branches in the main loop1030from working, or stops at least one discharging branch of the multiple discharging branches in the main loop1030from working.

Optionally, as another embodiment, when the uninterruptible power supply1000is switched to the bypass working mode from the main loop working mode, the processor1010further stops applying a drive signal to a switch tube of the inverter circuit, so as to stop the inverter circuit from working; when the bypass1050is abnormal, the processor1010provides the drive signal for the switch tube of the inverter circuit, so as to enable the inverter circuit to work.

For operations and functions of each unit of the uninterruptible power supply1000, reference may be made to the method inFIG. 2. To avoid repetition, details are not described herein again.

FIG. 11is a schematic structural diagram of an uninterruptible power supply1100according to another embodiment of the present invention. The uninterruptible power supply1100includes a processor1110, a memory1120, a main loop1130, a communication bus1140, and a bypass1150.

The main loop1130includes a rectifier circuit, a discharging circuit, a bus bar, and an inverter circuit, where the rectifier circuit provides electric energy for the bus bar, and the inverter circuit extracts the electric energy from the bus bar. The bypass1150is configured to directly provide mains power for a load. The processor1110invokes, using the communication bus1140, code stored in the memory1120, and is configured to switch the uninterruptible power supply1100to a bypass working mode from a main loop working mode, so as to provide the mains power for the load through the bypass1150; determine the working mode of the uninterruptible power supply1100; and when the uninterruptible power supply1100is switched to the bypass working mode from the main loop working mode and a voltage of the bus bar of the uninterruptible power supply1100is higher than a first threshold, stop the rectifier circuit and/or the discharging circuit in the main loop1130from working, and when it is determined that the voltage of the bus bar in the main loop1130is lower than a second threshold, enable the rectifier circuit and/or the discharging circuit to work, where the first threshold is greater than the second threshold, and the first threshold and the second threshold are respectively an upper limit value and a lower limit value of a working voltage of the bus bar, or the first threshold and the second threshold are within a range of the working voltage of the bus bar.

According to this embodiment of the present invention, when an uninterruptible power supply is switched to run in a bypass working mode, in a case in which it is determined that a voltage of a bus bar of the uninterruptible power supply is higher than a first threshold, a rectifier circuit and/or a discharging circuit is stopped from working; in a case in which it is determined that the voltage of the bus bar is lower than a second threshold, the rectifier circuit and/or the discharging circuit is enabled to work, thereby reducing working loss of the uninterruptible power supply and effectively improving working efficiency of the uninterruptible power supply.

Optionally, as another embodiment, the main loop1130further includes a charger and an auxiliary power supply, where the charger of the uninterruptible power supply1100provides power for the auxiliary power supply of the uninterruptible power supply1100. The processor1110is further configured to determine an output voltage of the charger in the main loop1130; and when the uninterruptible power supply1100is switched to the bypass working mode from the main loop working mode and the output voltage of the charger in the main loop1130is higher than a third threshold, stop the charger from providing power for the auxiliary power supply, and when the output voltage of the charger is lower than a fourth threshold, provide power for the auxiliary power supply again, where the charger provides power for the auxiliary power supply, the third threshold is greater than the fourth threshold, and the third threshold and the fourth threshold are respectively an upper limit value and a lower limit value of a working voltage of the auxiliary power supply, or the third threshold and the fourth threshold are within a range of the working voltage of the auxiliary power supply.

For operations and functions of each unit of the uninterruptible power supply1100, reference may be made to the method inFIG. 5. To avoid repetition, details are not described herein again.

FIG. 12is a schematic structural diagram of an uninterruptible power supply1200according to another embodiment of the present invention. The uninterruptible power supply1200includes a processor1210, a memory1220, a main loop1230, a communication bus1240, and a bypass1250.

The main loop1230includes multiple rectifier branches and multiple discharging branches. The bypass1250is configured to directly provide mains power for a load. The processor1210invokes, using the communication bus1240, code stored in the memory1220, and is configured to switch the uninterruptible power supply1200to a bypass working mode from a main loop working mode, so as to provide the mains power for the load through the bypass1250; determine the working mode of the uninterruptible power supply1200; and when the uninterruptible power supply1200is switched to the bypass working mode from the main loop working mode, stop at least one rectifier branch of the multiple rectifier branches in the main loop1230from working, or stop at least one discharging branch of the multiple discharging branches in the main loop1230from working.

According to this embodiment of the present invention, when an uninterruptible power supply is switched to run in a bypass working mode, in a case in which it is determined that a voltage of a bus bar of the uninterruptible power supply is higher than a first threshold, at least one rectifier branch of multiple rectifier branches or at least one discharging branch of multiple discharging branches in the uninterruptible power supply is stopped from working, thereby reducing working loss of the uninterruptible power supply and effectively improving working efficiency of the uninterruptible power supply.

Optionally, as another embodiment, the main loop1230further includes an inverter circuit. When the uninterruptible power supply1200is switched to the bypass working mode from the main loop working mode, the processor1210further stops applying a drive signal to a switch tube of the inverter circuit, so as to stop the inverter circuit from working; when the bypass1250is abnormal, the processor1210provides the drive signal for the switch tube of the inverter circuit, so as to enable the inverter circuit to work.

For operations and functions of each unit of the uninterruptible power supply1200, reference may be made to the method inFIG. 5. To avoid repetition, details are not described herein again.