Power supply system

Abstract

The invention discloses a power supply system, and relates to the technical field of electrical connection devices, and the power supply system comprises a power supply input end which is used for accessing commercial power; the power supply output end is used for accessing a load; the rectifying circuit and the inverter circuit are sequentially connected in series between the power input end and the power output end; the first switching circuit is connected in series between the power supply input end and the input end of the rectifying circuit; the input end of the energy storage circuit is connected with the output end of the first switching circuit, and the output end of the energy storage circuit is connected with the input end of the inverter circuit; the control unit is respectively connected with the controlled end of the first switching circuit and the controlled end of the energy storage circuit; the invention aims to reduce the economic burden of electricity utilization of the user.

Description

Technical Field

[0001] The present invention relates to the technical field of electrical connection devices, and particularly relates to a power supply system. Background Art

[0002] To ensure the safety of the power grid and relieve the load pressure on the power grid during peak electricity consumption periods, the state has introduced a peak-valley electricity price policy, dividing the daily electricity consumption period into peak, valley, and normal periods, and implementing differential electricity prices. For example, according to the document jointly issued by the Price Bureau and the Electric Power Industry Bureau of the Economic and Trade Commission, residential electricity consumption implements peak-valley electricity. It divides 24 hours of a day into two time periods. The 14 hours from 8:00 to 22:00 are called the peak period, and the peak electricity price is 0.568 yuan per degree; the 10 hours from 22:00 to 8:00 the next day are called the valley period, and the valley electricity price is 0.288 yuan per degree.

[0003] Due to people's daily work and rest habits and the regularity of production and life, the peak electricity consumption periods of most users highly coincide with the peak period, and less electricity is consumed during the valley period. This electricity consumption pattern results in a higher electricity cost for users, thus increasing the economic burden of users' electricity consumption. Summary of the Invention

[0004] The main object of the present invention is to propose a power supply system, aiming to reduce the economic burden of users' electricity consumption.

[0005] To achieve the above object, a power supply system proposed by the present invention includes:

[0006] A power input terminal for connecting to the mains power;

[0007] A power output terminal for connecting to a load;

[0008] A rectifier circuit and an inverter circuit, which are sequentially connected in series between the power input terminal and the power output terminal;

[0009] A first switch circuit, which is connected in series between the power input terminal and the input terminal of the rectifier circuit;

[0010] An energy storage circuit, the input terminal of the energy storage circuit is connected to the output terminal of the first switch circuit, and the output terminal of the energy storage circuit is connected to the input terminal of the inverter circuit;

[0011] A control unit, the control unit is respectively connected to the controlled terminal of the first switch circuit and the controlled terminal of the energy storage circuit, and the control unit is used to control the first switch circuit to be disconnected within a first preset time period and control the energy storage circuit to output a DC power supply;

[0012] The control unit is further configured to control the first switching circuit to conduct within a second preset time period, so that the energy storage circuit stores the accessed commercial power, and control the rectification circuit and the inversion circuit to be connected to the commercial power in sequence, so as to rectify and invert the accessed commercial power and output it to the load;

[0013] Wherein, the first preset time period is the peak period, and the second preset time period is the valley period.

[0014] In one embodiment, the energy storage circuit includes:

[0015] A charging circuit and a battery module, the input end of the charging circuit is connected to the output end of the first switching circuit, the output end of the charging circuit is connected to the input end of the battery module, the output end of the battery module is connected to the input end of the inversion circuit, and the controlled end of the battery module is electrically connected to the control unit.

[0016] In one embodiment, the energy storage circuit further includes:

[0017] A first diode and a second diode, the output end of the charging circuit is electrically connected to the anode of the first diode, the cathode of the first diode is electrically connected to the input end of the battery module, the output end of the battery module is electrically connected to the anode of the second diode, and the output end of the second diode is electrically connected to the input end of the inversion circuit.

[0018] In one embodiment, the power supply system further includes:

[0019] A second switching circuit, which is serially arranged between the power input end and the power output end, and the controlled end of the second switching circuit is electrically connected to the control unit;

[0020] A first monitoring system, the first monitoring system is electrically connected to the control unit, and the first monitoring system is configured to detect the working state of the energy storage circuit and output a corresponding first status signal;

[0021] When the control unit determines that the energy storage circuit is abnormal according to the first status signal, it controls the second switching circuit to conduct the path between the power input end and the power output end.

[0022] In one embodiment, the second switching circuit includes:

[0023] A first relay and a first static transfer switch, the first end of the first relay is connected to the power input end, the second end of the first relay is connected to the power output end, the first end of the first static transfer switch is connected to the power input end, and the second end of the first static transfer switch is connected to the power output end;

[0024] When the control unit determines that the energy storage circuit is abnormal according to the first status signal, it sequentially controls the first static transfer switch and the first relay to conduct, so that the load is connected to the commercial power through the first static transfer switch / the first relay.

[0025] In one embodiment, the first switch circuit includes:

[0026] A second static transfer switch and a second relay. The first end of the second relay is connected to the power input terminal, the second end of the second relay is connected to the input terminal of the rectifier circuit, the input terminal of the second static transfer switch is connected to the first end of the second relay, the output terminal of the second static transfer switch is connected to the second end of the second relay, and the controlled terminals of the second static transfer switch and the second relay are both electrically connected to the control unit;

[0027] The control unit is configured to sequentially control the second static transfer switch and the second relay to disconnect within a first preset time period, and is further configured to sequentially control the second static transfer switch and the first switch circuit to conduct within a second preset time period.

[0028] In one embodiment, the power supply system further includes:

[0029] A third switch circuit. The input terminal of the third switch circuit is connected to the second end of the second relay, the output terminal of the third switch circuit is connected to the power output terminal, and the controlled terminal of the third switch circuit is electrically connected to the control unit;

[0030] A second monitoring system. The second monitoring system is electrically connected to the control unit, and the second monitoring system is configured to detect the working state of the energy storage circuit and output a corresponding second status signal;

[0031] When the control unit determines that the energy storage circuit is abnormal according to the second status signal, it sequentially controls the second static transfer switch and the second relay to conduct, and controls the third switch circuit to conduct, so that the load is connected to the commercial power through the path where the second static transfer switch / the second relay and the third switch circuit are located.

[0032] In one embodiment, the third switch circuit includes:

[0033] A third relay and a third static transfer switch, wherein a first end of the third relay is connected to a second end of the second relay, a second end of the third relay is connected to the power output terminal, a first end of the third static transfer switch is connected to the second end of the second relay, and a second end of the third static transfer switch is connected to the power output terminal;

[0034] When the control unit determines that the energy storage circuit is abnormal according to the second status signal, it sequentially controls the third static transfer switch and the third relay to conduct, and sequentially controls the second static transfer switch and the second relay to conduct.

[0035] In an embodiment, the control unit is electrically connected to a controlled end of the inverter circuit, and the power supply system further includes:

[0036] A synchronization detection circuit, a detection end of the synchronization detection circuit is connected to the power input terminal, an output end of the synchronization detection circuit is electrically connected to the control unit, and the synchronization detection circuit is used to detect the frequency and phase of the commercial power and output a corresponding synchronization detection signal;

[0037] The control unit is used to control the inverter circuit to convert the DC power input by the energy storage circuit into an AC power output with the same frequency and phase as the commercial power according to the synchronization detection signal.

[0038] In an embodiment, the power supply system further includes:

[0039] A power quantity detection circuit, the power quantity detection circuit is used to detect the remaining power quantity of the energy storage circuit and output a corresponding power quantity signal, and the control unit is used to determine the remaining power quantity of the energy storage circuit according to the power quantity signal;

[0040] The control unit is further used to control the first switch circuit to disconnect when the remaining power quantity of the energy storage circuit is greater than a preset power quantity and the current time is within the first preset time period;

[0041] The control unit is further used to control the first switch circuit to conduct when the remaining power quantity of the energy storage circuit is less than or equal to the preset power quantity.

[0042] In an embodiment, the first preset time period includes the initial stage and the end stage of the peak period, and the control unit is used to control the first switch circuit to conduct at the initial stage of the peak period and when the remaining power quantity of the energy storage circuit reaches a second preset power quantity;

[0043] The control unit is further used to control the first switch circuit to conduct at the end stage of the peak period and when the remaining power quantity of the energy storage circuit reaches a first preset power quantity;

[0044] Wherein, the second preset power quantity is greater than the first preset power quantity.

[0045] In one embodiment, the power supply system further includes:

[0046] A third monitoring system, which is communicatively connected to the control unit, and is configured to detect the power of the load and output a corresponding power detection signal;

[0047] The control unit is configured to determine the power of the load according to the power detection signal, and the control unit is further configured to control the energy storage circuit to output direct current to the load when the power of the load is greater than a preset power threshold, the first switch circuit is turned on, and the remaining power quantity of the energy storage circuit is greater than or equal to the second preset power quantity, so that the commercial power and the energy storage circuit jointly supply power to the load;

[0048] Alternatively, the control unit is configured to control the first switch circuit to be turned on when the power of the load is greater than a preset power threshold and the first switch circuit is turned off, so that the commercial power and the energy storage circuit jointly supply power to the load.

[0049] The technical solution of the present invention includes a first switch circuit, an energy storage circuit, and a control unit. The first switch circuit is serially arranged between the power input end and the input end of the rectifier circuit. The input end of the energy storage circuit is connected to the output end of the first switch circuit, and the output end of the energy storage circuit is connected to the input end of the inverter circuit. The control unit is configured to control the first switch circuit to be turned off within a first preset time period and control the energy storage circuit to output a direct current power supply. The control unit is further configured to control the first switch circuit to be turned on within a second preset time period, so that the energy storage circuit stores the commercial power connected thereto, and control the rectifier circuit and the inverter circuit to be connected to the commercial power in sequence, so as to perform rectification and inversion processing on the connected commercial power and output it to the load. With such a setting, in practical applications, the power supply system of the present invention stores the electric energy with a lower electricity cost during the valley period and supplies the electric energy stored during the valley period to the load during the peak period with a higher electricity cost, so as to reduce the duration of the commercial power supplying power to the load during the peak period. This power supply method not only reduces the user's economic burden of electricity consumption, but also alleviates the power supply pressure of the power grid during the peak period and improves the operation efficiency of the power grid. Description of the Drawings

[0050] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on the structures shown in these drawings without creative efforts.

[0051] Figure 1 Schematic diagram of a module according to an embodiment of the present invention;

[0052] Figure 2 Schematic diagram of a module according to another embodiment of the present invention;

[0053] Figure 3 Schematic diagram of a circuit structure according to another embodiment of the present invention;

[0054] Figure 4 Schematic diagram of a module according to still another embodiment of the present invention;

[0055] Figure 5 Schematic diagram of a module according to yet another embodiment of the present invention;

[0056] Figure 6 Schematic diagram of a circuit structure according to yet another embodiment of the present invention;

[0057] Figure 7 Schematic diagram of a module according to still another embodiment of the present invention;

[0058] Figure 8 Schematic diagram of a module according to another embodiment of the present invention;

[0059] Figure 9 Schematic diagram of a circuit structure according to another embodiment of the present invention;

[0060] Figure 10 Schematic diagram of a module according to another embodiment of the present invention;

[0061] Figure 11 Schematic diagram of a module according to yet another embodiment of the present invention.

[0062] Description of the reference numerals in the drawings:

[0063] 10. Rectifier circuit; 20. Inverter circuit; 30. First switch circuit; 31. Second static transfer switch; 40. Energy storage circuit; 41. Charging circuit; 42. Battery module; 50. Control unit; 60. First monitoring system; 70. Second switch circuit; 71. First static transfer switch; 80. Second monitoring system; 90. Third switch circuit; 91. Third static transfer switch; 100. Synchronous detection circuit; 110. Power detection circuit; 120. Third monitoring system; 130. PFC module. Detailed implementation manners

[0064] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0065] It should be noted that if there are directional indications (such as up, down, left, right, front, back...) involved in the embodiments of the present invention, then such directional indications are only used to explain the relative positional relationship, movement conditions, etc. between components in a certain specific posture. If this specific posture changes, then the directional indications will also change accordingly.

[0066] In addition, if there are descriptions such as "first", "second", etc. involved in the embodiments of the present invention, then such descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, if "and / or" or "and / or" appears throughout the text, its meaning includes three parallel scenarios. Taking "A and / or B" as an example, it includes scenario A, or scenario B, or the scenario where both A and B are satisfied simultaneously. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the fact that those skilled in the art can implement it. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0067] To ensure the safety of the power grid and relieve the load pressure on the power grid during peak electricity consumption periods, the state has introduced a peak-valley electricity price policy, dividing the daily electricity consumption period into peak, valley, and normal periods, and implementing differential electricity prices. For example, according to the document jointly issued by the Price Bureau and the Electric Power Industry Bureau of the Economic and Trade Commission, for residential electricity consumption, peak-valley electricity is implemented. It divides 24 hours of a day into two time periods. The 14 hours from 8:00 to 22:00 are called the peak period, and the peak electricity price is 0.568 yuan per degree; the 10 hours from 22:00 to 8:00 the next day are called the valley period, and the valley electricity price is 0.288 yuan per degree.

[0068] Due to people's daily work and rest habits and the regularity of production and life, the peak electricity consumption periods of most users highly coincide with the peak period, and the electricity consumption is less during the valley period. This electricity consumption mode results in a higher electricity cost for users, thus increasing the economic burden of users' electricity consumption.

[0069] Therefore, the present invention proposes a power supply system aimed at reducing the economic burden of users' electricity consumption. In an embodiment of the present invention, referring to Figure 1 , the power supply system includes:

[0070] A power input terminal for connecting to the mains power;

[0071] A power output terminal for connecting to a load;

[0072] A rectifier circuit 10 and an inverter circuit 20 are serially arranged in sequence between the power input end and the power output end;

[0073] A first switch circuit 30, the first switch circuit 30 is serially arranged between the power input end and the input end of the rectifier circuit 10;

[0074] An energy storage circuit 40, the input end of the energy storage circuit 40 is connected to the output end of the first switch circuit 30, and the output end of the energy storage circuit 40 is connected to the input end of the inverter circuit 20;

[0075] A control unit 50, the control unit 50 is respectively connected to the controlled end of the first switch circuit 30 and the controlled end of the energy storage circuit 40, and the control unit 50 is used to control the first switch circuit 30 to disconnect within a first preset time period and control the energy storage circuit 40 to output a DC power supply;

[0076] The control unit 50 is further used to control the first switch circuit 30 to conduct within a second preset time period, so that the energy storage circuit 40 stores the incoming mains power, and control the rectifier circuit 10 and the inverter circuit 20 to be connected to the mains power in sequence, so as to rectify and invert the incoming mains power and output it to the load;

[0077] Wherein, the first preset time period is the peak period, and the second preset time period is the valley period.

[0078] In this embodiment, the first switch circuit 30 can be implemented by at least one switching device, such as a contactor, a circuit breaker, and a relay.

[0079] In this embodiment, the energy storage circuit 40 can be implemented by a charging circuit 41 and a battery module 42. Refer to Figure 9 , the input end of the charging circuit 41 is connected to the output end of the first switch circuit 30, the output end of the charging circuit 41 is connected to the input end of the battery module 42, the output end of the battery module 42 is connected to the input end of the inverter circuit 20, and the controlled end of the battery module 42 is electrically connected to the control unit 50. The charging circuit 41 is a device or circuit for converting the mains power into a voltage and current suitable for charging the battery circuit 42, and usually includes a rectifier (converting alternating current to direct current), a filter (smoothing the output of the direct current), and a voltage regulator (ensuring a stable output voltage).

[0080] It can be understood that in the case where the charging circuit 41 does not include a rectifier, the input end of the charging circuit 41 is connected to the output end of the rectifier circuit 10, so that the battery module 42 stores the direct current output by the rectifier circuit 10 through the charging circuit 41.

[0081] In addition, the energy storage circuit 40 further includes a first diode D1 and a second diode D2. The output end of the charging circuit 41 is electrically connected to the anode of the first diode D1. The cathode of the first diode D1 is electrically connected to the input end of the battery module 42. The output end of the battery module 42 is electrically connected to the anode of the second diode D2. The output end of the second diode D2 is electrically connected to the input end of the inverter circuit 20. The first diode D1 is used to prevent the current of the battery module from flowing back into the charging circuit 41, and the second diode D2 is used to prevent the direct current output by the rectifier circuit 10 from flowing back into the battery module 42.

[0082] In this embodiment, referring to Figure 11 , the power supply system may further include a PFC module 130. The input end of the PFC module 130 is connected to the output end of the rectifier circuit 10, and the output end of the PFC module 130 is connected to the input end of the inverter circuit 20. The PFC module 130 is used to improve the power factor of the direct current output by the rectifier circuit 10 and reduce the harmonic distortion existing therein, thereby improving the effective utilization rate of electric energy. In addition, the output end of the energy storage circuit 40 may be connected to the input end of the PFC module 130 to improve the power factor of the direct current output by the energy storage circuit 40 and reduce the harmonic distortion existing therein, thereby improving the effective utilization rate of the electric energy stored in the energy storage circuit 40 by the load.

[0083] The technical solution of the present invention includes a first switch circuit 30, an energy storage circuit 40, and a control unit 50. The first switch circuit 30 is serially arranged between the power input end and the input end of the rectifier circuit 10. The input end of the energy storage circuit 40 is connected to the output end of the first switch circuit 30, and the output end of the energy storage circuit 40 is connected to the input end of the inverter circuit 20. The control unit 50 is used to control the first switch circuit 30 to be turned off within a first preset time period and control the energy storage circuit 40 to output a direct current power supply. The control unit 50 is further used to control the first switch circuit 30 to be turned on within a second preset time period, so that the energy storage circuit 40 stores the incoming commercial power, and control the rectifier circuit 10 and the inverter circuit 20 to be connected to the commercial power in sequence to perform rectification and inversion processing on the incoming commercial power and then output it to the load. With such a setting, in practical applications, the power supply system of the present invention stores the electric energy with a lower electricity fee during the valley period and supplies the electric energy stored during the valley period to the load during the peak period with a higher electricity fee, so as to reduce the power supply duration of the commercial power to the load during the peak period. This power supply method not only reduces the user's economic burden of electricity consumption, but also alleviates the power supply pressure of the power grid during the peak period and improves the operation efficiency of the power grid.

[0084] It should be noted that when the energy storage circuit 40 fails, there may be a risk of disconnection in the inverter circuit 20. If the inverter circuit 20 is disconnected, the energy storage circuit 40 cannot supply power to the load through the inverter circuit 20, and the mains power cannot supply power to the load through the first switch circuit 30, the rectifier circuit 10, and the inverter circuit 20 in sequence, causing the load to stop working. When the load is a server, the server shutdown means business interruption, which will have a serious impact on the enterprise's operation and user experience.

[0085] In response to this, in an embodiment of the present invention, referring to Figure 2 , the power supply system further includes:

[0086] A second switch circuit 70, serially arranged between the power input terminal and the power output terminal, and the controlled terminal of the second switch circuit 70 is electrically connected to the control unit 50;

[0087] A first monitoring system 60, the first monitoring system 60 is electrically connected to the control unit 50, and the first monitoring system 60 is used to detect the working state of the energy storage circuit 40 and output a corresponding first status signal;

[0088] When the control unit 50 determines that the energy storage circuit 40 is abnormal according to the first status signal, it controls the second switch circuit 70 to conduct the path between the power input terminal and the power output terminal.

[0089] In this embodiment, the second switch circuit 70 can be implemented by at least one switching device, such as a contactor, a circuit breaker, and a relay.

[0090] In this embodiment, the first monitoring system 60 can determine the working state of the energy storage circuit 40 by detecting the terminal voltage of the energy storage circuit 40 (such as a battery pack or a supercapacitor). When the terminal voltage is not within the normal range, it can be determined that the energy storage circuit 40 is abnormal. The first monitoring system 60 can also determine the working state of the energy storage circuit 40 by detecting the charge and discharge current of the energy storage circuit 40. When the charge and discharge current deviates from the preset value, it can be determined that the energy storage circuit 40 is abnormal.

[0091] Through the above settings, the second switch circuit 70 is a bypass switch. When the power supply system of the present invention determines that the energy storage circuit 40 is abnormal, it conducts the second switch circuit 70, enabling the load to be directly connected to the mains power through the second switch circuit 70, thereby ensuring the uninterrupted operation of the load and avoiding the situation where the load cannot be connected to the mains power and stops running due to the disconnection of the inverter circuit 20 or the abnormality of the energy storage circuit 40.

[0092] It should be noted that in addition to being connected to the same commercial power supply as the first switching circuit 30, the second switching circuit 70 can also be connected to a commercial power supply with a different source from that of the first switching circuit 30. In this way, when the commercial power supply connected to the first switching circuit 30 is powered off, the control unit 50 controls the second switching circuit 70 to conduct, so that the load is connected to another commercial power supply through the second switching circuit 70, ensuring the uninterrupted operation of the load.

[0093] In addition, when the second switching circuit 70 is implemented solely by a relay, since the mechanical actions during the relay switching (such as the electromagnet attracting and the contacts closing) require a certain amount of time and cannot achieve millisecond-level switching. When the power-off response time of the load is short, the relatively long switching time may cause the load to experience a short-term shutdown situation, which will have a serious impact on the load. For example, the stored data may be lost or damaged, or the production may be interrupted, affecting production efficiency.

[0094] In response to this, referring to Figure 3 , in an embodiment, the second switching circuit 70 includes:

[0095] A first relay K1 and a first static transfer switch 71. The first end of the first relay K1 is connected to the power input terminal, the second end of the first relay K1 is connected to the power output terminal, the first end of the first static transfer switch 71 is connected to the power input terminal, and the second end of the first static transfer switch 71 is connected to the power output terminal;

[0096] When the control unit 50 determines that the energy storage circuit 40 is abnormal according to the first status signal, it sequentially controls the first static transfer switch 71 and the first relay K1 to conduct, so that the load is connected to the commercial power supply through the first static transfer switch 71 / the first relay K1.

[0097] With the above settings, since the static transfer switch can complete the switching action within 8 millimeters, which is much faster than the time required for the relay to complete the switching action. Therefore, when the control unit 50 determines that the energy storage circuit 40 is abnormal, the first static transfer switch 71 can close in an extremely short time, so that the load is quickly connected to the commercial power supply through the first static transfer switch 71, thus ensuring the uninterrupted operation of the load.

[0098] It should be noted that since the static transfer switch cannot carry a large current for a long time, after the control unit 50 controls the first static transfer switch 71 to conduct, it then controls the first relay K1 to conduct, so that the first relay K1 bypasses the first static transfer switch 71, and the load is connected to the commercial power supply through the first relay K1. It can be understood that the relay is a mechanical switch, and after conduction, the contact resistance is extremely low, which is suitable for carrying current for a long time and can prevent the first static transfer switch 71 from overheating or being damaged due to a relatively long continuous conduction time.

[0099] When the first switch circuit 30 is implemented only by a relay, since the mechanical actions (such as the electromagnet attracting and the contacts closing) during the relay switching require a certain amount of time and cannot achieve millisecond-level switching, when the current time enters the valley period, it takes a certain amount of time for the load to switch from being connected to the energy storage circuit 40 to being connected to the mains. If the power-off response time of the load is short, the relatively long switching time may cause the load to experience a short-term shutdown, and the short-term shutdown will have a serious impact on the load, such as data stored being lost or damaged, or production being interrupted, affecting production efficiency.

[0100] In response to this, referring to Figure 4 , the power supply system further includes:

[0101] A second static transfer switch 31 and a second relay K2. The first end of the second relay K2 is connected to the power input terminal, the second end of the second relay K2 is connected to the input terminal of the rectifier circuit 10, the input terminal of the second static transfer switch 31 is connected to the first end of the second relay K2, the output terminal of the second static transfer switch 31 is connected to the second end of the second relay K2, and the controlled terminals of both the second static transfer switch 31 and the second relay K2 are electrically connected to the control unit 50;

[0102] The control unit 50 is configured to sequentially control the second static transfer switch 31 and the second relay K2 to be turned off within a first preset time period, and is further configured to sequentially control the second static transfer switch 31 and the first switch circuit 30 to be turned on within a second preset time period.

[0103] In this embodiment, since the static transfer switch can complete the switching operation within 8 milliseconds, which is much faster than the time required for the relay to complete the switching operation, when the current time enters the valley period, the control unit 50 sequentially controls the second static transfer switch 31 and the second relay K2 to be turned on. The second static transfer switch 31 can close in an extremely short time, so that the load can be switched from being connected to the energy storage circuit 40 to being connected to the mains within an extremely short time, thus ensuring the uninterrupted operation of the load.

[0104] In this embodiment, referring to Figure 5 , the power supply system further includes:

[0105] A third switch circuit 90. The input terminal of the third switch circuit 90 is connected to the second end of the second relay K2, the output terminal of the third switch circuit 90 is connected to the power output terminal, and the controlled terminal of the third switch circuit 90 is electrically connected to the control unit 50;

[0106] The second monitoring system 80 is electrically connected to the control unit 50. The second monitoring system 80 is configured to detect the operating state of the energy storage circuit 40 and output a corresponding second status signal.

[0107] When the control unit 50 determines that the energy storage circuit 40 is abnormal according to the second status signal, it sequentially controls the second static transfer switch 31 and the second relay K2 to conduct, and controls the third switch circuit 90 to conduct, so that the load is connected to the commercial power through the path where the second static transfer switch 31 / the second relay K2 and the third switch circuit 90 are located.

[0108] In this embodiment, the second monitoring system 80 can determine the operating state of the energy storage circuit 40 by detecting the terminal voltage of the energy storage circuit 40 (such as a battery pack or a supercapacitor). When the terminal voltage is not within the normal range, it can be determined that the energy storage circuit 40 is abnormal. The second monitoring system 80 can also determine the operating state of the energy storage circuit 40 by detecting the charge and discharge current of the energy storage circuit 40. When the charge and discharge current deviates from the preset value, it can be determined that the energy storage circuit 40 is abnormal.

[0109] With the above settings, the third switch circuit 90 is a bypass switch. When the power supply system of the present invention determines that the energy storage circuit 40 is abnormal, it conducts the third switch circuit 90, so that the load is directly connected to the commercial power through the third switch circuit 90, thereby ensuring the uninterrupted operation of the load and avoiding the situation that the load cannot be connected to the commercial power and stops running due to the disconnection of the inverter circuit 20 or the abnormality of the energy storage circuit 40.

[0110] It should be noted that, in addition to being able to access the same commercial power as the second relay K2, the third switch circuit 90 can also access a commercial power different from the second relay K2, so that when the commercial power accessed by the second relay K2 is powered off, the control unit 50 controls the third switch circuit 90 to conduct, so that the load is connected to another commercial power through the third switch circuit 90, ensuring the uninterrupted operation of the load.

[0111] In addition, when the third switch circuit 90 is implemented solely by a relay, since the mechanical actions during the relay switching (such as the electromagnet attracting and the contact closing) require a certain amount of time and cannot achieve millisecond-level switching, when the power-off response time of the load is short, the longer switching time may cause the load to experience a short-term shutdown situation, and the short-term shutdown situation will have a serious impact on the load, such as the loss or damage of stored data, or the interruption of production affecting production efficiency.

[0112] In response to this, referring to Figure 6 , in one embodiment, the third switch circuit 90 includes:

[0113] A third relay K3 and a third static transfer switch 91, a first end of the third relay K3 is connected to a second end of the second relay K2, a second end of the third relay K3 is connected to the power output terminal, a first end of the third static transfer switch 91 is connected to the second end of the second relay K2, and a second end of the third static transfer switch 91 is connected to the power output terminal;

[0114] When the control unit 50 determines that the energy storage circuit 40 is abnormal according to the second status signal, the control unit 50 sequentially controls the third static transfer switch 91 and the third relay K3 to conduct, and sequentially controls the second static transfer switch 31 and the second relay K2 to conduct.

[0115] With the above settings, since the static transfer switch can complete the switching operation within 8 millimeters, which is much faster than the time required for the relay to complete the switching operation. Therefore, when the control unit 50 determines that the energy storage circuit 40 is abnormal, the second static transfer switch 31 and the third static transfer switch 91 can close in an extremely short time, so that the load can be quickly connected to the commercial power, thereby ensuring the uninterrupted operation of the load.

[0116] It should be noted that since the static transfer switch cannot carry large current for a long time, after the control unit 50 controls the third static transfer switch 91 to conduct, it then controls the third relay K3 to conduct, so that the third relay K3 bypasses the third static transfer switch 91, and the load is connected to the commercial power through the third relay K3. It can be understood that the relay is a mechanical switch, and the contact resistance is extremely low after conduction, which is suitable for carrying current for a long time, and can prevent the third static transfer switch 91 from overheating or being damaged due to continuous conduction for a long time.

[0117] In the power supply system, when the load switches from being powered by the energy storage circuit 40 to being powered by the commercial power (or vice versa), if the alternating current output by the inverter circuit 20 is not synchronized with the frequency and phase of the commercial power, it will cause current impact or voltage fluctuation. Under the influence of the current impact or voltage fluctuation, the load may stop running or be damaged.

[0118] In response to this, in an embodiment of the present invention, referring to Figure 7 , the control unit 50 is electrically connected to the controlled end of the inverter circuit 20, and the power supply system further includes:

[0119] A synchronization detection circuit 100, a detection end of the synchronization detection circuit 100 is connected to the power input terminal, an output end of the synchronization detection circuit 100 is electrically connected to the control unit 50, and the synchronization detection circuit 100 is used to detect the frequency and phase of the commercial power and output a corresponding synchronization detection signal;

[0120] The control unit 50 is configured to control the inverter circuit 20 to convert the DC power input from the energy storage circuit 40 into an AC power output with the same frequency and phase as the mains power according to the synchronization detection signal.

[0121] In this embodiment, the synchronization detection circuit 100 can be implemented by a phase-locked loop, a zero-crossing detection circuit, or digital signal processing (DSP).

[0122] With the above arrangement, when the power supply system of the present invention switches from mains power supply to the energy storage circuit 40 for power supply, since the AC power output after the DC power output from the energy storage circuit 40 is converted by the inverter circuit 20 is synchronized with the frequency and phase of the mains power, there will be no current impact or voltage fluctuation during the switching process, ensuring uninterrupted operation of the load and reducing harmonic interference and power loss.

[0123] In an embodiment of the present invention, referring to Figure 8 , the power supply system further includes:

[0124] A power quantity detection circuit 110, which is configured to detect the remaining power quantity of the energy storage circuit 40 and output a corresponding power quantity signal, and the control unit 50 is configured to determine the remaining power quantity of the energy storage circuit 40 according to the power quantity signal;

[0125] The control unit 50 is further configured to control the first switch circuit 30 to disconnect when the remaining power quantity of the energy storage circuit 40 is greater than a preset power quantity and the current time is within the first preset time period;

[0126] The control unit 50 is further configured to control the first switch circuit 30 to conduct when the remaining power quantity of the energy storage circuit 40 is less than or equal to the preset power quantity.

[0127] In this embodiment, there is a certain corresponding relationship between the voltage of the energy storage circuit 40 and its remaining power quantity (usually represented by a voltage - SOC curve), and the power quantity detection circuit 110 can estimate the remaining power quantity of the energy storage circuit 40 by measuring the terminal voltage of the energy storage circuit 40.

[0128] With the above arrangement, the power supply system of the present invention switches to mains power supply in time when the power quantity of the energy storage circuit 40 is insufficient, ensuring uninterrupted operation of the load and charging the energy storage circuit 40. When the power quantity of the energy storage circuit 40 recovers and the current time is in the peak period, the first switch circuit 30 is controlled to disconnect again to switch the energy storage circuit 40 to supply power to the load, thereby reducing the user's electricity economic burden.

[0129] It should be considered that the energy storage circuit of the traditional power supply circuit often controls the energy storage unit to enter the deep discharge state (such as SOC≤20%) during the peak period of power consumption. After the energy storage circuit enters the deep discharge state multiple times, irreversible damages such as vulcanization of the internal battery plates and loss of electrolyte may occur, resulting in a significant reduction in the cycle life of the energy storage circuit.

[0130] In this regard, in one embodiment, the first preset time period includes the initial stage and the end stage of the peak period. The control unit 50 is configured to control the first switch circuit to turn on at the initial stage of the peak period and when the remaining power of the energy storage circuit 40 reaches the second preset power.

[0131] The control unit 50 is further configured to control the first switch circuit to turn on at the end stage of the peak period and when the remaining power of the energy storage circuit 40 reaches the first preset power.

[0132] Wherein, the second preset power is greater than the first preset power.

[0133] In this embodiment, the control unit 50 releases the shallow-layer power (for example, 50% - 80%) of the energy storage circuit 40 at the initial stage of the peak period, that is, retains more than 20% of the capacity as an emergency reserve. This setting not only avoids the energy storage circuit 40 from frequently entering the deep discharge state and extends its cycle life, but also can provide emergency power supply to the load when the mains power fails or the load power is large.

[0134] The control unit 50 also controls the energy storage circuit 40 to discharge deeply (for example, 80% - 100%) at the end stage of the peak period, avoiding the electrochemical aging caused by the long-term retention of charges in the energy storage circuit 40, and creating capacity space for charging during the valley period, improving the utilization efficiency of the energy storage circuit 40.

[0135] It should be noted that the initial stage of the peak period is the stage when the peak period starts. At this time, the power of the load gradually increases, and it is suitable for shallow discharge to relieve the grid pressure and retain the emergency reserve. The end stage of the peak period is the stage when the peak period ends. At this time, the power of the load gradually decreases, and it is suitable for deep discharge to make full use of the high-price peak electricity and create space for charging during the valley period.

[0136] In addition, in the case of load overload, it may not be possible to meet the high-power demand of the load only by the mains power or the energy storage circuit 40. In this regard, in one embodiment, refer to Figure 10 , the power supply system further includes:

[0137] A third monitoring system 120, the third monitoring system 120 is communicatively connected to the control unit 50, and the third monitoring system 120 is configured to detect the power of the load and output a corresponding power detection signal.

[0138] The control unit 50 is configured to determine the power of the load according to the power detection signal. The control unit 50 is further configured to control the energy storage circuit 40 to output direct current to the load when the power of the load is greater than a preset power threshold, the first switch circuit 30 is turned on, and the remaining power of the energy storage circuit 40 is greater than or equal to a second preset power, so that the mains power and the energy storage circuit 40 jointly supply power to the load.

[0139] In this embodiment, the third monitoring system 120 can be implemented by a voltage detection circuit. The voltage detection circuit is configured to detect the supply voltage of the load and output a corresponding voltage detection signal. The control unit 50 is configured to determine the supply voltage of the load according to the voltage detection signal, and determine that the power of the load is greater than the preset power threshold (i.e., the load is overloaded) when the supply voltage of the load is greater than the preset voltage threshold.

[0140] Based on the above embodiment, when the remaining power of the energy storage circuit 40 drops to the second preset power, the control unit 50 controls the first switch circuit 30 to be turned on, so that the mains power supplies power to both the energy storage circuit 40 and the load at the same time. When the control unit 50 detects that the power of the load is greater than the preset power threshold (i.e., the load is overloaded), since the energy storage circuit 40 still stores a certain amount of power at the beginning of the peak period, the control unit 50 can control the energy storage circuit 40 to discharge, so that the energy storage circuit 40 and the mains power, which were originally in a charging state, jointly supply power to the load, thereby meeting the high-power demand of the load.

[0141] In another embodiment, when the energy storage circuit 40 supplies power to the load during the peak period (at this time the first switch circuit 30 is off), the output power of only the energy storage circuit 40 cannot meet the high-power demand when the load is overloaded.

[0142] In this regard, the control unit 50 is configured to control the first switch circuit 30 to be turned on when the power of the load is greater than the preset power threshold and the first switch circuit 30 is off, so that the mains power and the energy storage circuit 40 supply power to the load at the same time.

[0143] With such a setting, in practical applications, when the load is overloaded, the power supply system of the present invention can jointly supply power to the load by controlling the mains power and the energy storage circuit 40 to meet the high-power demand of the load, ensuring that the load can still operate continuously under overloaded conditions, and significantly improving the power supply reliability of the power supply system of the present invention.

[0144] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structural transformation made under the technical concept of the present invention by using the content of the specification and drawings of the present invention, or any direct / indirect application in other related technical fields is included in the patent protection scope of the present invention.

Claims

1. A power supply system, characterized in that: include: Power input terminal, used to connect to the mains; Power output terminal, used to connect to the load; A rectifier circuit and an inverter circuit are sequentially connected in series between the power input terminal and the power output terminal; A first switch circuit, the first switch circuit is arranged in series between the power input terminal and the input terminal of the rectifier circuit; An energy storage circuit, wherein an input end of the energy storage circuit is connected to an output end of the first switch circuit, and an output end of the energy storage circuit is connected to an input end of the inverter circuit; A control unit, the control unit being connected to a controlled end of the first switch circuit and a controlled end of the energy storage circuit respectively, the control unit being used to control the first switch circuit to be disconnected within a first preset time period, and to control the energy storage circuit to output a DC power supply; The control unit is further used to control the first switch circuit to be turned on within a second preset time period, so that the energy storage circuit stores energy for the connected mains power, and control the rectifier circuit and the inverter circuit to be connected to the mains power in sequence, so as to rectify and invert the connected mains power and then output it to the load; The first preset time period is a peak period, and the second preset time period is a valley period.

2. The power supply system according to claim 1, characterized in that: The energy storage circuit comprises: A charging circuit and a battery module, wherein the input end of the charging circuit is connected to the output end of the first switching circuit, the output end of the charging circuit is connected to the input end of the battery module, the output end of the battery module is connected to the input end of the inverter circuit, and the controlled end of the battery module is electrically connected to the control unit.

3. The power supply system according to claim 2, characterized in that: The energy storage circuit also includes: A first diode and a second diode, the output end of the charging circuit is electrically connected to the anode of the first diode, the cathode of the first diode is electrically connected to the input end of the battery module, the output end of the battery module is electrically connected to the anode of the second diode, and the output end of the second diode is electrically connected to the input end of the inverter circuit.

4. The power supply system according to claim 1, characterized in that: The power supply system further comprises: A second switch circuit is arranged in series between the power input terminal and the power output terminal, and a controlled end of the second switch circuit is electrically connected to the control unit; a first monitoring system, the first monitoring system being electrically connected to the control unit, and the first monitoring system being used to detect a working state of the energy storage circuit and output a corresponding first state signal; When the control unit determines according to the first state signal that the energy storage circuit is abnormal, the control unit controls the second switch circuit to conduct the path between the power input terminal and the power output terminal.

5. The power supply system according to claim 4, characterized in that: The second switch circuit comprises: a first relay and a first static transfer switch, wherein a first end of the first relay is connected to the power input end, a second end of the first relay is connected to the power output end, a first end of the first static transfer switch is connected to the power input end, and a second end of the first static transfer switch is connected to the power output end; When the control unit determines according to the first state signal that the energy storage circuit is abnormal, it sequentially controls the first static transfer switch and the first relay to be turned on, so that the load is connected to the mains through the first static transfer switch / the first relay.

6. The power supply system according to claim 1, characterized in that: The first switch circuit comprises: a second static transfer switch and a second relay, wherein a first end of the second relay is connected to the power input end, a second end of the second relay is connected to the input end of the rectifier circuit, an input end of the second static transfer switch is connected to the first end of the second relay, an output end of the second static transfer switch is connected to the second end of the second relay, and a controlled end of the second static transfer switch and a controlled end of the second relay are both electrically connected to the control unit; The control unit is used to sequentially control the second static transfer switch and the second relay to be disconnected within a first preset time period, and is also used to sequentially control the second static transfer switch and the first switch circuit to be connected within a second preset time period.

7. The power supply system according to claim 6, characterized in that: The power supply system further comprises: a third switch circuit, wherein an input end of the third switch circuit is connected to the second end of the second relay, an output end of the third switch circuit is connected to the power supply output end, and a controlled end of the third switch circuit is electrically connected to the control unit; a second monitoring system, the second monitoring system being electrically connected to the control unit, and the second monitoring system being used to detect the working state of the energy storage circuit and output a corresponding second state signal; When the control unit determines that the energy storage circuit is abnormal according to the second state signal, it sequentially controls the second static transfer switch and the second relay to be turned on, and controls the third switch circuit to be turned on, so that the load is connected to the mains through the path where the second static transfer switch / the second relay and the third switch circuit are located.

8. The power supply system according to claim 7, characterized in that: The third switch circuit comprises: a third relay and a third static transfer switch, wherein a first end of the third relay is connected to a second end of the second relay, a second end of the third relay is connected to the power output terminal, a first end of the third static transfer switch is connected to a second end of the second relay, and a second end of the third static transfer switch is connected to the power output terminal; When the control unit determines that the energy storage circuit is abnormal according to the second state signal, it sequentially controls the third static transfer switch and the third relay to be turned on, and sequentially controls the second static transfer switch and the second relay to be turned on.

9. The power supply system according to any one of claims 1 to 8, characterized in that: The control unit is electrically connected to the controlled end of the inverter circuit, and the power supply system further includes: A synchronous detection circuit, wherein the detection end of the synchronous detection circuit is connected to the power input end, the output end of the synchronous detection circuit is electrically connected to the control unit, and the synchronous detection circuit is used to detect the frequency and phase of the mains power and output a corresponding synchronous detection signal; The control unit is used to control the inverter circuit according to the synchronization detection signal to convert the DC power input by the energy storage circuit into an AC power output with the same frequency and phase as the mains.

10. The power supply system according to claim 1, wherein: The power supply system further comprises: A power detection circuit, the power detection circuit is used to detect the remaining power of the energy storage circuit and output a corresponding power signal, and the control unit is used to determine the remaining power of the energy storage circuit according to the power signal; The control unit is further configured to control the first switch circuit to be disconnected when the remaining power of the energy storage circuit is greater than a first preset power and the current time is within the first preset time period; The control unit is further configured to control the first switch circuit to be turned on when the remaining power of the energy storage circuit is less than or equal to a first preset power.

11. The power supply system according to claim 10, characterized in that: The first preset time period includes an early peak period and an late peak period, and the control unit is used to control the first switch circuit to be turned on when the remaining power of the energy storage circuit reaches a second preset power at the early peak period; The control unit is further used to control the first switch circuit to be turned on when the remaining power of the energy storage circuit reaches a first preset power at the end of the peak period; Wherein, the second preset power is greater than the first preset power.

12. The power supply system according to claim 11, characterized in that: The power supply system further comprises: a third monitoring system, the third monitoring system establishing a communication connection with the control unit, the third monitoring system being used to detect the power of the load and output a corresponding power detection signal; The control unit is used to determine the power of the load according to the power detection signal, and the control unit is also used to control the energy storage circuit to output direct current to the load when the power of the load is greater than a preset power threshold, and when the first switch circuit is turned on and the remaining power of the energy storage circuit is greater than or equal to a second preset power, so that the mains power and the energy storage circuit jointly power the load; Alternatively, the control unit is used to control the first switch circuit to be turned on when the power of the load is greater than a preset power threshold and the first switch circuit is disconnected, so that the AC power and the energy storage circuit jointly supply power to the load.

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