A power supply control circuit of an uninterruptible power supply and an uninterruptible power supply

Abstract

The utility model discloses a kind of power supply control circuit of uninterruptible power supply and uninterruptible power supply.The power supply control circuit of uninterruptible power supply includes commercial power incoming line circuit breaker, generator, power supply switching device, overvoltage and undervoltage current limiting protector and opening and closing control module;The input end of commercial power incoming line circuit breaker is accessed three-phase commercial power, and the output end of commercial power incoming line circuit breaker is connected with the first input end of power supply switching device, and the second input end of power supply switching device is connected with generator, and the output end of power supply switching device is connected with uninterruptible power supply;The input end of overvoltage and undervoltage current limiting protector is connected with the input end of commercial power incoming line circuit breaker, and the output end of overvoltage and undervoltage current limiting protector is connected with the input end of opening and closing control module, and the control end of opening and closing control module is respectively connected with the opening coil and closing coil of commercial power incoming line circuit breaker.The utility model can make uninterruptible power supply not be influenced by abnormal input power supply, and can guarantee the long-term stable operation of uninterruptible power supply.

Description

Technical Field

[0001] This utility model relates to the field of power supply technology, and in particular to a power supply control circuit and an uninterruptible power supply. Background Technology

[0002] An uninterruptible power supply (UPS) is a device that provides continuous power for a short period of time when the mains power fails or the voltage is abnormal.

[0003] Under normal conditions, an uninterruptible power supply (UPS) uses AC mains power as its input. In the event of a mains power outage, a generator provides the AC input. The input AC power is rectified and inverted to supply power to the load. When there is no AC input power, the battery bank provides power through its inverter output. However, when the UPS malfunctions, connected equipment may fail to operate normally. Current technology uses an undervoltage trip coil to quickly trip the circuit breaker, cutting off the undervoltage input power, or the circuit breaker's own protection mechanism to cut off abnormal input power, thus protecting the UPS from abnormal mains power. However, once the mains power stabilizes, the circuit breaker cannot automatically return to its original operating state, failing to guarantee long-term stable operation of the UPS. Utility Model Content

[0004] This utility model provides a power supply control circuit and an uninterruptible power supply (UPS) to ensure that the UPS is not affected by abnormal input power and can guarantee the long-term stable operation of the UPS.

[0005] In a first aspect, the present invention provides a power supply control circuit for an uninterruptible power supply, the power supply control circuit for the uninterruptible power supply including a mains power incoming circuit breaker, a generator, a power switching device, an over / under voltage current limiting protector, and a switching control module.

[0006] The input terminal of the mains power incoming circuit breaker is connected to three-phase mains power, the output terminal of the mains power incoming circuit breaker is connected to the first input terminal of the power switching device, the second input terminal of the power switching device is connected to the generator, and the output terminal of the power switching device is connected to an uninterruptible power supply.

[0007] The input terminal of the over / under voltage current limiting protector is connected to the input terminal of the mains incoming circuit breaker and connected to the three-phase mains power. The output terminal of the over / under voltage current limiting protector is connected to the input terminal of the tripping and closing control module. The control terminal of the tripping and closing control module is connected to the tripping coil and the closing coil of the mains incoming circuit breaker, respectively.

[0008] Optionally, the three-phase mains power includes phase A, phase B, and phase C;

[0009] The input terminals of the mains power incoming circuit breaker include an A-phase input terminal, a B-phase input terminal, and a C-phase input terminal. The A-phase input terminal of the mains power incoming circuit breaker is connected to the A-phase mains power, the B-phase input terminal of the mains power incoming circuit breaker is connected to the B-phase mains power, and the C-phase input terminal of the mains power incoming circuit breaker is connected to the C-phase mains power.

[0010] The input terminals of the over / under voltage current limiting protector include a neutral input terminal, an A-phase input terminal, a B-phase input terminal, and a C-phase input terminal. The A-phase input terminal of the over / under voltage current limiting protector is connected to the A-phase input terminal of the mains power incoming circuit breaker. The B-phase input terminal of the over / under voltage current limiting protector is connected to the B-phase input terminal of the mains power incoming circuit breaker. The C-phase input terminal of the over / under voltage current limiting protector is connected to the C-phase input terminal of the mains power incoming circuit breaker. The neutral input terminal of the over / under voltage current limiting protector is connected to the neutral wire.

[0011] The output terminals of the over / under voltage current limiting protector include a neutral output terminal, an A-phase output terminal, a B-phase output terminal, and a C-phase output terminal.

[0012] The input terminals of the circuit breaker control module include a first input terminal and a second input terminal. The first input terminal of the circuit breaker control module is connected to any one of the A-phase output terminal, B-phase output terminal and C-phase output terminal of the over- and under-voltage current limiting protector. The second input terminal of the circuit breaker control module is connected to the neutral line output terminal of the over- and under-voltage current limiting protector.

[0013] Optionally, the power supply control circuit of the uninterruptible power supply further includes a transfer switch; the opening and closing control module includes an intermediate relay, a first time relay, and a second time relay.

[0014] The first terminal of the intermediate relay serves as the first input terminal of the circuit breaker control module, and the second terminal of the intermediate relay serves as the second input terminal of the circuit breaker control module.

[0015] The first terminal of the second time relay is connected to the first terminal of the intermediate relay, and the second terminal of the second time relay is connected to the second terminal of the intermediate relay.

[0016] The first end of the coil of the intermediate relay is connected to the power supply, the second end of the coil of the intermediate relay is connected to the first end of the first time relay, and the second end of the first time relay is connected to the neutral wire.

[0017] The first end of the changeover switch is connected to the power supply, and the second end of the changeover switch is connected to the first end of the coil of the first time relay and the first end of the coil of the second time relay.

[0018] The second end of the coil of the first time relay is connected to the opening coil of the mains power incoming circuit breaker; the second end of the coil of the second time relay is connected to the closing coil of the mains power incoming circuit breaker.

[0019] The tripping coil trips when energized, disconnecting the input and output terminals of the mains power incoming circuit breaker. The closing coil closes when energized, connecting the input and output terminals of the mains power incoming circuit breaker.

[0020] Optionally, the power supply control circuit of the uninterruptible power supply further includes a first manual trip switch and a second manual trip switch;

[0021] The third terminal of the changeover switch is connected to the power supply, and the fourth terminal of the changeover switch is connected to the first terminal of the first manual trip switch and the first terminal of the second manual trip switch.

[0022] The second end of the first manual trip switch is connected to the trip coil, and the second end of the second manual trip switch is connected to the closing coil.

[0023] Optionally, when the voltage across the intermediate relay is 0, the second time relay is disconnected and the intermediate relay is closed.

[0024] When the voltage across the intermediate relay is not zero, the intermediate relay is disconnected and the second time relay is closed.

[0025] Optionally, the first time relay and the second time relay are time-delay circuit breakers;

[0026] The delay time for the first time relay to disconnect after closing is greater than the opening time of the tripping coil; the delay time for the second time relay to disconnect after closing is greater than the closing time of the closing coil.

[0027] Optionally, the selector switch includes a selector knob.

[0028] Optionally, the generator is a three-phase generator.

[0029] Optionally, the power supply control circuit of the uninterruptible power supply may further include a generator power detection device;

[0030] The input terminal of the generator power detection device is connected to the output terminal of the over / under voltage current limiting protector, and the output terminal of the generator power detection device is connected to the control terminal of the generator.

[0031] The circuit breaker control module is used to control the tripping coil to trip when the output voltage of the over / under voltage current limiting protector is 0, and to control the closing coil to close when the output voltage of the over / under voltage current limiting protector is the mains voltage; the generator power detection device is used to control the generator to start when the output voltage of the over / under voltage current limiting protector is 0, and to control the generator to shut down when the output voltage of the over / under voltage current limiting protector is the mains voltage.

[0032] Secondly, this utility model embodiment also provides an uninterruptible power supply, which includes the power supply control circuit of the uninterruptible power supply in any embodiment of this utility model.

[0033] This utility model provides a power supply control circuit for an uninterruptible power supply (UPS) and the UPS itself. The power supply control circuit includes a mains power inlet circuit breaker, a generator, a power switching device, an over / under voltage current limiting protector, and a switching control module. The input terminal of the mains power inlet circuit breaker is connected to three-phase mains power. The output terminal of the mains power inlet circuit breaker is connected to the first input terminal of the power switching device. The second input terminal of the power switching device is connected to the generator. The output terminal of the power switching device is connected to the UPS, thereby providing the UPS with three-phase mains power and three-phase AC power generated by the generator, ensuring that the UPS is not affected by abnormal input power. The input of the over / under voltage current limiting protector... The circuit breaker is connected to the input terminal of the mains power incoming circuit breaker to supply three-phase mains power. The output terminal of the over / under voltage and current limiting protector is connected to the input terminal of the trip / close control module. The control terminal of the trip / close control module is connected to the trip coil and the close coil of the mains power incoming circuit breaker, respectively. The trip coil and the close coil are controlled according to the fluctuation of the three-phase mains power. When the mains power input of the uninterruptible power supply experiences a large fluctuation, the trip coil can control the mains power incoming circuit breaker to trip. When the mains power returns to stability, the close coil can control the mains power incoming circuit breaker to close, restoring the mains power supply. This ensures that the uninterruptible power supply is not affected by abnormal input power and guarantees the long-term stable operation of the uninterruptible power supply. Attached Figure Description

[0034] Figure 1 A schematic diagram of the power supply control circuit of an uninterruptible power supply provided for an embodiment of this utility model;

[0035] Figure 2 A schematic diagram of the power supply control circuit of another uninterruptible power supply provided in an embodiment of this utility model;

[0036] Figure 3 A schematic diagram of the power supply control circuit of another uninterruptible power supply provided in an embodiment of this utility model;

[0037] Figure 4 A schematic diagram of the structure of the changeover switch provided in an embodiment of this utility model;

[0038] Figure 5 A schematic diagram showing the connection relationship between the first manual trip switch and the second manual trip switch provided in this embodiment of the utility model. Detailed Implementation

[0039] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, not the entire structure.

[0040] This utility model embodiment provides a power supply control circuit for an uninterruptible power supply. Figure 1 A schematic diagram of the power supply control circuit for an uninterruptible power supply provided in an embodiment of this utility model is shown below. Figure 1 As shown, the power supply control circuit of the uninterruptible power supply includes a mains incoming circuit breaker 110, a generator 130, a power switching device 120, an over / under voltage current limiting protector 140, and a switching control module 150.

[0041] The input terminal of the mains power incoming circuit breaker 110 is connected to the three-phase mains power, the output terminal of the mains power incoming circuit breaker 110 is connected to the first input terminal of the power switching device 120, the second input terminal of the power switching device 120 is connected to the generator 130, and the output terminal of the power switching device 120 is connected to the uninterruptible power supply.

[0042] The input terminal of the over / under voltage current limiting protector 140 is connected to the input terminal of the mains incoming circuit breaker 110, and is connected to the three-phase mains power. The output terminal of the over / under voltage current limiting protector 140 is connected to the input terminal of the tripping and closing control module 150. The control terminal of the tripping and closing control module 150 is connected to the tripping coil 1101 and the closing coil 1102 of the mains incoming circuit breaker 110, respectively.

[0043] The uninterruptible power supply (UPS) can be an uninterruptible motor drive (UMD), which is a dedicated UPS for industrial motors and other power equipment. The UMD is a high-reliability power device designed specifically for industrial environments, aiming to provide stable power support for critical industrial equipment. The entire system includes a rectifier, an inverter, and a battery bank. Under normal conditions, the UMD uses three-phase mains power as its AC input. In the event of a three-phase mains power outage, a generator 130 provides the AC input. The input AC power is rectified and inverted to supply power to the load. When there is no AC input power, the battery bank inverts and outputs power to the load.

[0044] Specifically, the mains incoming circuit breaker 110 can be tripped via the tripping coil 1101 and closed via the closing coil 1102. The tripping coil 1101 trips when energized, and the closing coil 1102 closes when energized. The generator 130 generates electricity and supplies it to the power switching device 120. The power switching device 120 can switch between supplying power to the uninterruptible power supply (UPS) via the generator 130 and the three-phase mains power supplied by the mains incoming circuit breaker 110, thus providing the UPS with both three-phase mains power and three-phase AC power generated by the generator 130.

[0045] The over / under voltage current limiting protector 140 is an important circuit protection mechanism, mainly used to prevent circuit damage due to excessively low voltage or excessive current. The over / under voltage current limiting protector 140 can collect the three-phase mains voltage entering the mains power circuit breaker 110. When the three-phase mains voltage is detected to be lower than the set value, the over / under voltage current limiting protector 140 outputs a voltage of 0. When the three-phase mains voltage is detected to be greater than or equal to the set value, and the three-phase mains voltage returns to normal, the over / under voltage current limiting protector 140 outputs a voltage equal to the actual three-phase mains voltage. A tripping and closing control module 150 is connected to the output terminal of the over / under voltage current limiting protector 140. The control terminals of the tripping and closing control module 150 are respectively connected to the tripping coil 1101 and the closing coil 1102 of the mains incoming circuit breaker 110. The tripping and closing control module 150 automatically controls whether the tripping coil 1101 and the closing coil 1102 are energized according to the output voltage of the over / under voltage current limiting protector 140, thereby automatically controlling the mains incoming circuit breaker 110 to perform tripping and closing operations. This allows for the control of the trip coil 1101 and the closing coil 1102 based on fluctuations in the three-phase mains power. When significant fluctuations occur in the three-phase mains power input of the uninterruptible power supply (UPS), the trip coil 1101 controls the mains power incoming circuit breaker 110 to trip. When the mains power stabilizes, the closing coil 1102 controls the mains power incoming circuit breaker 110 to close, restoring mains power supply. This ensures that the UPS is unaffected by abnormal input power and guarantees its long-term stable operation.

[0046] This utility model embodiment provides a power supply control circuit for an uninterruptible power supply (UPS). The power supply control circuit includes a mains power input circuit breaker, a generator, a power switching device, an over / under voltage current limiting protector, and a switching control module. The input terminal of the mains power input circuit breaker is connected to three-phase mains power. The output terminal of the mains power input circuit breaker is connected to the first input terminal of the power switching device. The second input terminal of the power switching device is connected to the generator. The output terminal of the power switching device is connected to the UPS, thereby providing the UPS with three-phase mains power and three-phase AC power generated by the generator, so that the UPS is not affected by abnormal input power. The input terminal of the over / under voltage current limiting protector is connected to the mains power input circuit breaker. The input terminal of the incoming circuit breaker is connected to the three-phase mains power. The output terminal of the over / under voltage and current limiting protector is connected to the input terminal of the trip / close control module. The control terminal of the trip / close control module is connected to the trip coil and the close coil of the mains incoming circuit breaker, respectively. The trip coil and the close coil are controlled according to the fluctuation of the three-phase mains power. When the mains power input of the uninterruptible power supply experiences a large fluctuation, the trip coil can control the mains incoming circuit breaker to trip. When the mains power returns to stability, the close coil can control the mains incoming circuit breaker to close, restoring the mains power supply. This ensures that the uninterruptible power supply is not affected by abnormal input power and guarantees the long-term stable operation of the uninterruptible power supply.

[0047] To further ensure that the uninterruptible power supply (UPS) is unaffected by abnormal input power and to guarantee its long-term stable operation, this embodiment of the invention also provides another UPS power supply control circuit. Figure 2 A schematic diagram of the power supply control circuit for another uninterruptible power supply provided in an embodiment of this utility model is shown below. Figure 2 As shown, the three-phase mains power includes phase A, phase B, and phase C; the input terminals of the mains power incoming circuit breaker 110 include phase A, phase B, and phase C input terminals. The phase A input terminal of the mains power incoming circuit breaker 110 is connected to the phase A mains power, the phase B input terminal of the mains power incoming circuit breaker 110 is connected to the phase B mains power, and the phase C input terminal of the mains power incoming circuit breaker 110 is connected to the phase C mains power.

[0048] The input terminals of the over / under voltage current limiting protector 140 include a neutral input terminal, an A-phase input terminal, a B-phase input terminal, and a C-phase input terminal. The A-phase input terminal of the over / under voltage current limiting protector 140 is connected to the A-phase input terminal of the mains power incoming circuit breaker 110. The B-phase input terminal of the over / under voltage current limiting protector 140 is connected to the B-phase input terminal of the mains power incoming circuit breaker 110. The C-phase input terminal of the over / under voltage current limiting protector 140 is connected to the C-phase input terminal of the mains power incoming circuit breaker 110. The neutral input terminal of the over / under voltage current limiting protector 140 is connected to the neutral line N.

[0049] The output terminals of the over / under voltage current limiting protector 140 include a neutral output terminal, an A-phase output terminal, a B-phase output terminal, and a C-phase output terminal; the input terminals of the tripping and closing control module 150 include a first input terminal and a second input terminal. The first input terminal of the tripping and closing control module 150 is connected to any one of the A-phase output terminal, the B-phase output terminal, and the C-phase output terminal of the over / under voltage current limiting protector 140, and the second input terminal of the tripping and closing control module 150 is connected to the neutral output terminal of the over / under voltage current limiting protector 140.

[0050] Specifically, the mains incoming circuit breaker 110, generator 130, power switching device 120 and uninterruptible power supply are all connected via three-phase lines, thereby transmitting three-phase power to the uninterruptible power supply. The over / under voltage current limiting protector 140 is connected to the three-phase mains power via the three-phase lines. The neutral input terminal of the over / under voltage current limiting protector 140 is connected to the neutral line N, thereby connecting to the three-phase mains power input to the mains incoming circuit breaker 110 to determine the fluctuation of the three-phase mains power input to the mains incoming circuit breaker 110. The first input terminal of the tripping and closing control module 150 is connected to any one of the A-phase output terminal, B-phase output terminal, and C-phase output terminal of the over / under voltage current limiting protector 140. The second input terminal of the tripping and closing control module 150 is connected to the neutral line output terminal of the over / under voltage current limiting protector 140. Based on the output voltage of the over / under voltage current limiting protector 140, the module automatically controls whether the tripping coil 1101 and the closing coil 1102 are energized, thereby automatically controlling the mains incoming circuit breaker 110 to perform tripping and closing operations. This ensures that the uninterruptible power supply is not affected by abnormal input power and guarantees the long-term stable operation of the uninterruptible power supply.

[0051] Figure 3 A schematic diagram of the power supply control circuit for another uninterruptible power supply provided in this embodiment of the utility model. Figure 4 This is a schematic diagram of the structure of the changeover switch provided in an embodiment of the present utility model. Figure 3 The changeover switch is not shown; only the connection between the changeover switch interface and the opening / closing control module 150 is shown. Figure 3 and Figure 4 As shown, the circuit breaker control module 150 includes an intermediate relay KA, a first time relay KT1, and a second time relay KT2; the power supply control circuit of the uninterruptible power supply also includes a changeover switch SA.

[0052] The first terminal of the intermediate relay KA serves as the first input terminal of the circuit breaker control module 150, and the second terminal of the intermediate relay KA serves as the second input terminal of the circuit breaker control module 150.

[0053] The first terminal of the second time relay KT2 is connected to the first terminal of the intermediate relay KA, and the second terminal of the second time relay KT2 is connected to the second terminal of the intermediate relay KA.

[0054] The first end of the coil ka of the intermediate relay KA is connected to the power supply, and the second end of the coil ka of the intermediate relay KA is connected to the first end of the first time relay KT1. The second end of the first time relay KT1 is connected to the neutral line N.

[0055] The first terminal of the changeover switch SA is connected to the power supply VDD, and the second terminal 202 of the changeover switch SA is connected to the first terminal of the coil kt1 of the first time relay KT1 and the first terminal of the coil kt2 of the second time relay KT2.

[0056] The second terminal of the coil kt1 of the first time relay KT1 is connected to the trip coil 1101 of the mains power incoming circuit breaker 110; the second terminal of the coil kt2 of the second time relay KT2 is connected to the closing coil 1102 of the mains power incoming circuit breaker 110. The trip coil 1101 trips when energized, disconnecting the input and output terminals of the mains power incoming circuit breaker 110; the closing coil 1102 closes when energized, connecting the input and output terminals of the mains power incoming circuit breaker 110.

[0057] In this system, the coil ka of the intermediate relay KA, the first terminal of the coil kt1 of the first time relay KT1, and the coil kt2 of the second time relay KT2 are all relay coils. The relay coil is an important component of the relay, and its main function is to generate electromagnetic attraction when energized, which drives the armature to close, thereby causing the contacts to change position. Specifically, when the coil is energized, current flows through it, generating an electromagnetic effect. Under the action of electromagnetic force, the armature overcomes the tension of the spring and is attracted to the iron core, completing the closure of the contacts.

[0058] Specifically, the power supply VDD can be a 220V AC power supply. When the changeover switch SA is rotated to automatic mode, the first terminal and the second terminal 202 of the changeover switch SA are connected, and the second terminal 202 of the changeover switch SA outputs 220V AC power. The A-phase power from the first output terminal of the over / under voltage current limiting protector 140 is used as the power supply for the coil kt2 of the second time relay KT2 and the coil ka of the intermediate relay KA. The three-phase power output from the over / under voltage current limiting protector 140 is used as the detection power supply for the motor power detection device 160. When the three-phase mains voltage is lower than the preset value, the output voltage of the over / under voltage current limiting protector 140 is 0; otherwise, its output is the actual three-phase mains voltage.

[0059] Optionally, when the voltage across the intermediate relay KA is 0, the second time relay KT2 is open and the intermediate relay KA is closed; when the voltage across the intermediate relay KA is not 0, the intermediate relay KA is open and the second time relay KT2 is closed.

[0060] When the changeover switch SA is rotated to automatic mode, when the output voltage of the over / under voltage current limiting protector 140 is 0, the coil kt2 of the second time relay KT2 and the coil ka of the intermediate relay KA are de-energized. The normally open contact of the second time relay KT2 remains normally open, the closing coil 1102 is not energized, the normally closed contact of the intermediate relay KA closes, the coil kt1 of the first time relay KT1 is energized, the normally open contact of the first time relay KT1 closes for 10 seconds and then opens, the opening coil 1101 is energized for 10 seconds, the mains power incoming circuit breaker 110 opens, and at this time the power switching device 120 successfully cuts off the under-voltage three-phase mains power, and the generator 130 supplies power to the uninterruptible power supply.

[0061] When the changeover switch SA is rotated to automatic mode, when the three-phase mains voltage returns to normal, the over / under voltage current limiting protector 140 outputs the actual three-phase mains voltage. The coil kt2 of the second time relay KT2 and the coil ka of the intermediate relay KA are energized. The normally open contact of the second time relay KT2 closes for 10 seconds and then opens. The closing coil 1102 is simultaneously energized for 10 seconds, the mains incoming circuit breaker 110 closes, the normally closed contact of the intermediate relay KA opens, the coil kt1 of the first time relay KT1 is de-energized, the normally open contact of the first time relay KT1 remains normally open, the opening coil 1101 remains de-energized, and the uninterruptible power supply restores the three-phase mains power supply.

[0062] Figure 5 A schematic diagram illustrating the connection relationship between the first manual trip switch and the second manual trip switch provided in this embodiment of the utility model is shown below. Figure 4 and Figure 5 As shown, the power supply control circuit of the uninterruptible power supply also includes a first manual trip switch SB1 and a second manual trip switch SB2.

[0063] The third terminal of the changeover switch SA is connected to the power supply VDD, and the fourth terminal 201 of the changeover switch SA is connected to the first terminal of the first manual trip switch SB1 and the first terminal of the second manual trip switch SB2. The second terminal of the first manual trip switch SB1 is connected to the trip coil 1101, and the second terminal of the second manual trip switch SB2 is connected to the closing coil 1102.

[0064] Specifically, the changeover switch SA also includes a local mode. When the changeover switch SA is switched to the local mode, the third terminal of the changeover switch SA is connected to the fourth terminal 201 of the changeover switch SA. The first terminal of the first manual trip switch SB1 and the first terminal of the second manual trip switch SB2 are both connected to the power supply VDD. By manually pressing the first manual trip switch SB1 or the second manual trip switch SB2, the trip coil 1101 or the closing coil 1102 can be energized, and the mains incoming circuit breaker 110 can be manually controlled to perform closing and tripping operations.

[0065] Optionally, the first time relay KT1 and the second time relay KT2 are time-delay circuit breakers.

[0066] Optionally, the delay time for the first time relay KT1 to disconnect after closing is greater than the opening time of the tripping coil 1101; the delay time for the second time relay KT2 to disconnect after closing is greater than the closing time of the closing coil 1102.

[0067] Specifically, the delay time can be 10 seconds. The normally open contact of the second time relay KT2 closes for 10 seconds and then opens, and the closing coil 1102 is simultaneously energized for 10 seconds, causing the mains power incoming circuit breaker 110 to close. The normally open contact of the first time relay KT1 closes for 10 seconds and then opens, and the opening coil 1101 is energized for 10 seconds, causing the mains power incoming circuit breaker 110 to open, thereby realizing the closing and opening of the mains power incoming circuit breaker 110.

[0068] Optionally, the selector switch SA has a selector knob.

[0069] Specifically, the changeover switch SA is equipped with a changeover knob, which can be used to control the mode of the changeover switch SA, switching it to local mode or automatic mode.

[0070] Optionally, generator 130 is a three-phase generator.

[0071] For details, please refer to Figure 3 Generator 130 is a three-phase generator that provides three-phase AC power to an uninterruptible power supply through a power switching device.

[0072] In some embodiments of this utility model, the power supply control circuit of the uninterruptible power supply further includes a generator power detection device 160; the input terminal of the generator power detection device 160 is connected to the output terminal of the over / under voltage current limiting protector 140, and the output terminal of the generator power detection device 160 is connected to the control terminal of the generator 130; the tripping control module 150 is used to control the tripping coil 1101 to trip when the output voltage of the over / under voltage current limiting protector 140 is 0, and to control the closing coil 1102 to close when the output voltage of the over / under voltage current limiting protector 140 is the mains voltage; the generator power detection device 160 is used to control the generator 130 to start when the output voltage of the over / under voltage current limiting protector 140 is 0, and to control the generator 130 to start and stop when the output voltage of the over / under voltage current limiting protector 140 is the mains voltage.

[0073] Specifically, when the changeover switch SA is switched to automatic mode, when the over / under voltage current limiting protector 140 detects that the mains voltage is lower than the set value, the output voltage of the over / under voltage current limiting protector is 0, the intermediate relay KA and the first time relay KT1 are activated, the trip coil 1101 is energized and trips the circuit breaker, and the generator power supply detection device 160 detects that the output voltage of the over / under voltage current limiting protector is 0 and controls the generator 130 to start automatically; when the over / under voltage current limiting protector 140 detects that the mains voltage has returned to normal and has exceeded the set time, the output voltage of the over / under voltage current limiting protector 140 is the mains voltage, the intermediate relay KA and the second time relay KT2 are activated, the closing coil 1102 is energized and closes the circuit breaker, the uninterruptible power supply restores mains power supply, and the generator power supply detection device 160 detects that the output voltage of the over / under voltage current limiting protector 140 is the mains voltage and controls the generator 130 to shut down, so that the uninterruptible power supply is not affected by the fluctuation of the three-phase mains power and ensures the long-term stable operation of the uninterruptible power supply.

[0074] When frequent fluctuations in mains voltage cause a malfunction in the UMD system, it leads to load power loss. The cause of the UMD malfunction is an excessive drop in mains voltage and a high frequency of fluctuations, which affects the normal operation of the UMD's internal circuitry. Existing solutions involve using an undervoltage trip coil to quickly trip the circuit breaker, cutting off the undervoltage input power, or using the circuit breaker's own protection mechanism to cut off the abnormal input power, thus protecting the UMD from abnormal mains power. However, once the mains power stabilizes, the circuit breaker cannot automatically return to its original operating state, thus failing to guarantee long-term stable operation of the UMD. The uninterruptible power supply (UPS) control circuit provided in this embodiment addresses this issue. When the mains power fluctuation range of the UMD input reaches a set value, the control device immediately controls the circuit breaker to trip, cutting off the mains power. Simultaneously, the generator detects the mains power outage and automatically starts to supply power to the UMD, protecting it from abnormal input power. When the mains power stabilizes and the duration reaches the set value, the control device controls the circuit breaker to close, restoring mains power supply and ensuring long-term stable operation of the UMD.

[0075] The opening and closing logic of the UMD mains incoming circuit breaker in the existing technology is relatively simple and the function is relatively simple. The main drawbacks are as follows: (1) When the mains voltage frequently fluctuates undervoltage, the circuit breaker does not open. The generator does not detect the mains power outage and the UMD is still powered by the mains. The large amplitude and frequency of the input voltage fluctuation can easily cause the UMD to malfunction, resulting in the loss of power to its load. (2) The mains incoming circuit breaker can be manually opened and closed, but cannot be automatically closed.

[0076] The uninterruptible power supply control circuit of this embodiment uses an over / under voltage current limiting protector 140, two time relays (first time relay KT1 and second time relay KT2), ​​one intermediate relay (intermediate relay KA), and one changeover switch (changeover switch SA) to form a control device that can automatically control the opening and closing of the mains incoming circuit breaker 110. The main advantages are as follows:

[0077] (1) Automatic mode and local mode can be selected by switching switch SA.

[0078] (2) In automatic mode, when the overvoltage and undervoltage current limiting protector 140 detects that the mains voltage is lower than the set value (which can be manually set in real time), the intermediate relay KA and the first time relay KT1 are activated, the trip coil 1101 is energized, the mains power incoming circuit breaker 110 trips, and the generator power detection device 160 detects the mains power interruption and controls the generator 130 to start automatically, so that the uninterruptible power supply is not affected by the fluctuation of the three-phase mains power and ensures the long-term stable operation of the uninterruptible power supply.

[0079] (3) In automatic mode, when the overvoltage and undervoltage current limiting protector 140 detects that the mains voltage has returned to normal and has exceeded the set time, the intermediate relay KA and the second time relay KT2 are activated, the closing coil 1102 is energized, the mains power incoming circuit breaker 110 is closed, the uninterruptible power supply restores the mains power supply, and the generator power detection device 160 controls the generator 130 to stop automatically after detecting that the mains power has been restored.

[0080] The power supply control circuit of the uninterruptible power supply in this embodiment combines the opening and closing principle of the mains incoming circuit breaker. It uses components such as undervoltage current limiting protector, first time relay, second time relay, intermediate relay, and changeover switch to design a new control logic and circuit, forming a control circuit. When the fluctuation range of the three-phase mains power input to the uninterruptible power supply reaches the set value, the mains incoming circuit breaker can be immediately controlled to open and disconnect the mains power. At the same time, the generator automatically starts after the three-phase mains power is cut off to supply power to the uninterruptible power supply, so that the uninterruptible power supply is not affected by abnormal input power. When the mains power recovers to a stable state and the duration reaches the set value, the mains incoming circuit breaker is controlled to close and restore the three-phase mains power supply, ensuring the long-term stable operation of the uninterruptible power supply.

[0081] This utility model embodiment also provides an uninterruptible power supply (UPS). The UPS in this utility model embodiment includes the power supply control circuit of the UPS in any embodiment of this utility model, thereby achieving the same function and technical effect as the power supply control circuit of the UPS.

[0082] The uninterruptible power supply (UPS) in this embodiment can be a UMD (Uninterruptible Damping Device), applicable to natural gas stations equipped with gas turbine compressor units and other UMD application environments. Important loads such as the lubricating oil cooling system, natural gas cooling system, and gas turbine cooling system of the gas turbine compressor unit are powered by the UMD. In natural gas stations, frequent fluctuations in mains voltage have led to UMD system failures. After a UMD failure, the load loses power, causing the operating gas turbine compressor unit to shut down. The cause of the UMD failure is excessive voltage drop and fluctuation frequency, affecting the normal operation of the UMD's internal circuitry. Existing solutions involve using an undervoltage trip coil to quickly trip the circuit breaker, cutting off the undervoltage input power, or using the circuit breaker's own protection action to cut off the abnormal input power, thus protecting the UMD from abnormal mains power. However, once the mains power stabilizes, the circuit breaker cannot automatically return to its original operating state, thus failing to guarantee long-term stable operation of the UMD. The UPS provided in this embodiment can provide a stable power supply, ensuring the normal operation of the gas turbine compressor unit and improving the reliability of natural gas transfer at the station.

[0083] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments. Many other equivalent embodiments may be included without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A power supply control circuit for an uninterruptible power supply, characterized by, The power supply control circuit of the uninterruptible power supply includes a mains incoming circuit breaker, a generator, a power switching device, an over / under voltage current limiting protector, and a switching control module. The input terminal of the mains power incoming circuit breaker is connected to three-phase mains power, the output terminal of the mains power incoming circuit breaker is connected to the first input terminal of the power switching device, the second input terminal of the power switching device is connected to the generator, and the output terminal of the power switching device is connected to an uninterruptible power supply. The input terminal of the over / under voltage current limiting protector is connected to the input terminal of the mains incoming circuit breaker and connected to the three-phase mains power. The output terminal of the over / under voltage current limiting protector is connected to the input terminal of the tripping and closing control module. The control terminal of the tripping and closing control module is connected to the tripping coil and the closing coil of the mains incoming circuit breaker, respectively.

2. The power supply control circuit of an uninterruptible power supply of claim 1, wherein, The three-phase mains power includes phase A mains power, phase B mains power and phase C mains power; The input terminals of the mains power incoming circuit breaker include an A-phase input terminal, a B-phase input terminal, and a C-phase input terminal. The A-phase input terminal of the mains power incoming circuit breaker is connected to the A-phase mains power, the B-phase input terminal of the mains power incoming circuit breaker is connected to the B-phase mains power, and the C-phase input terminal of the mains power incoming circuit breaker is connected to the C-phase mains power. The input terminals of the over / under voltage current limiting protector include a neutral input terminal, an A-phase input terminal, a B-phase input terminal, and a C-phase input terminal. The A-phase input terminal of the over / under voltage current limiting protector is connected to the A-phase input terminal of the mains power incoming circuit breaker. The B-phase input terminal of the over / under voltage current limiting protector is connected to the B-phase input terminal of the mains power incoming circuit breaker. The C-phase input terminal of the over / under voltage current limiting protector is connected to the C-phase input terminal of the mains power incoming circuit breaker. The neutral input terminal of the over / under voltage current limiting protector is connected to the neutral wire. The output terminals of the over / under voltage current limiting protector include a neutral output terminal, an A-phase output terminal, a B-phase output terminal, and a C-phase output terminal. The input terminals of the circuit breaker control module include a first input terminal and a second input terminal. The first input terminal of the circuit breaker control module is connected to any one of the A-phase output terminal, B-phase output terminal and C-phase output terminal of the over- and under-voltage current limiting protector. The second input terminal of the circuit breaker control module is connected to the neutral line output terminal of the over- and under-voltage current limiting protector.

3. The power supply control circuit of an uninterruptible power supply of claim 2, wherein, It also includes a changeover switch; the opening and closing control module includes an intermediate relay, a first time relay, and a second time relay. The first terminal of the intermediate relay serves as the first input terminal of the circuit breaker control module, and the second terminal of the intermediate relay serves as the second input terminal of the circuit breaker control module. The first terminal of the second time relay is connected to the first terminal of the intermediate relay, and the second terminal of the second time relay is connected to the second terminal of the intermediate relay. The first end of the coil of the intermediate relay is connected to the power supply, the second end of the coil of the intermediate relay is connected to the first end of the first time relay, and the second end of the first time relay is connected to the neutral wire. The first end of the changeover switch is connected to the power supply, and the second end of the changeover switch is connected to the first end of the coil of the first time relay and the first end of the coil of the second time relay. The second end of the coil of the first time relay is connected to the opening coil of the mains power incoming circuit breaker; the second end of the coil of the second time relay is connected to the closing coil of the mains power incoming circuit breaker. The tripping coil trips when energized, disconnecting the input and output terminals of the mains power incoming circuit breaker. The closing coil closes when energized, connecting the input and output terminals of the mains power incoming circuit breaker.

4. The power supply control circuit of claim 3, wherein, It also includes a first manual trip switch and a second manual trip switch; The third terminal of the changeover switch is connected to the power supply, and the fourth terminal of the changeover switch is connected to the first terminal of the first manual trip switch and the first terminal of the second manual trip switch. The second end of the first manual trip switch is connected to the trip coil, and the second end of the second manual trip switch is connected to the closing coil.

5. The power supply control circuit of claim 3, wherein, When the voltage across the intermediate relay is 0, the second time relay is disconnected, and the intermediate relay is closed. When the voltage across the intermediate relay is not zero, the intermediate relay is disconnected and the second time relay is closed.

6. The power supply control circuit of claim 3, wherein, The first time relay and the second time relay are time-delay circuit breakers; The delay time for the first time relay to disconnect after closing is greater than the opening time of the tripping coil; the delay time for the second time relay to disconnect after closing is greater than the closing time of the closing coil.

7. The power supply control circuit of claim 4, wherein, The selector switch has a selector knob inside.

8. The power supply control circuit of claim 1, wherein, The generator is a three-phase generator.

9. The power supply control circuit of an uninterruptible power supply according to any one of claims 1 to 8, characterized in that, The power supply control circuit of the uninterruptible power supply also includes a generator power detection device; The input terminal of the generator power detection device is connected to the output terminal of the over / under voltage current limiting protector, and the output terminal of the generator power detection device is connected to the control terminal of the generator. The circuit breaker control module is used to control the tripping coil to trip when the output voltage of the over / under voltage current limiting protector is 0, and to control the closing coil to close when the output voltage of the over / under voltage current limiting protector is the mains voltage; the generator power detection device is used to control the generator to start when the output voltage of the over / under voltage current limiting protector is 0, and to control the generator to shut down when the output voltage of the over / under voltage current limiting protector is the mains voltage.

10. An uninterruptible power supply, characterized by The uninterruptible power supply includes the power supply control circuit of the uninterruptible power supply according to any one of claims 1-9.

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