Base station energy storage equipment and control method thereof

Abstract

The invention discloses a base station energy storage device and a control method thereof, and belongs to the technical field of new energy. The equipment comprises a power supply module, a detection module, three switches, a rectifier, an inverter, an energy storage device, a charging power supply and a controller, wherein the controller is used for controlling the charging and discharging states of the energy storage device according to the operation state and the electricity price of a power grid and switching the power supply source of the inverter so as to supply power to a base station by using the inverter; the detection module is connected with the controller through a second switch and a third switch which are connected in series, the control end of the second switch is used for receiving output signals of the detection module, the detection module is connected with the input end of the rectifier through the first switch, and the output ends of the rectifier and the energy accumulator are connected with the inverter. The equipment can solve the technical problems that in the prior art, a base station needs to be transformed, the construction difficulty is large, the energy storage coverage rate is not high, and anti-islanding protection measures need to be taken when a power grid is powered off.

Description

Technical Field

[0001] The present invention relates to the field of new energy technology, and in particular to a base station energy storage device and a control method thereof. Background Art

[0002] The integrated energy storage technology of base stations refers to the technology that integrates the energy storage and backup power functions of base stations. Compared with traditional separate energy storage and backup power solutions, this technical model not only has better economic benefits, but also has higher energy utilization.

[0003] In the existing technology, the energy storage technology of base stations can generally be divided into two categories: DC side storage integration and AC side storage integration. Among them, DC side storage integration refers to adding energy storage equipment on the DC side of the power grid to achieve energy storage applications in base stations. Usually, switching power supplies, smart lithium batteries or time-controlled switches are used to achieve energy storage applications in base stations. Figures 1 to 3 , Figure 1 This is a schematic diagram of realizing the integrated application of base station energy storage by using a switching power supply. Figure 2 This is a schematic diagram of realizing the integrated application of base station energy storage using smart lithium batteries. Figure 3 This is a schematic diagram of realizing the integrated application of base station energy storage by means of time-controlled switches.

[0004] When using a switching power supply to implement energy storage applications in base stations, the energy storage control of the base station is achieved by controlling the on and off of the switching power supply. When the switching power supply is on, the power grid supplies power to the base station, and when the switching power supply is off, the battery pack supplies power to the base station. The energy storage method of the switching power supply needs to support the on and off functions of the time-sharing energy storage output. This method is suitable for newly built base stations. For old base stations, the base stations need to be renovated, and the on-site construction is difficult. The energy storage method of the smart lithium battery requires adding a bidirectional DCDC converter on the DC bus side of the battery pack and the power grid, and realizing the integrated charge and discharge control of the battery pack through the bidirectional DCDC converter. The time-controlled switch method requires adding a set of time-controlled switches between the switching power supply and the DC bus of the power grid, and realizing the integrated reserve control of the battery pack through the time-sharing on and off of the time-controlled switches, which has the problem of difficult on-site construction. Moreover, in all DC-side integrated storage technologies, the output power of the energy storage device can only power the DC devices in the base station, and cannot power some AC devices in the base station, such as air conditioners, lighting, sockets, etc. The output power of the energy storage device cannot cover all the equipment in the base station, and there is a problem of low energy storage coverage.

[0005] The AC side integrated storage usually connects the energy storage device in parallel to the AC bus side of the power grid, thus realizing the energy storage application of the base station. Figure 4 , Figure 4This is a schematic diagram of connecting energy storage equipment in parallel on the AC bus side of the power grid to realize the integrated application of base station energy storage. In this setting, the energy storage equipment can power both the DC equipment in the base station and the AC equipment in the base station. The output power of the energy storage equipment can cover all the equipment in the base station, and the energy storage coverage rate is high. However, this setting requires tracking the frequency and phase of the power grid, which is not only complicated to operate, but also requires anti-islanding protection measures when the power grid is outage, and the overall reliability of the energy storage equipment during operation cannot be guaranteed.

[0006] It can be seen that how to provide a base station energy storage device with simple construction, high energy storage coverage and no need for island protection measures when the power grid is outage is a technical problem that needs to be urgently solved by technical personnel in this field. Summary of the invention

[0007] In view of this, the purpose of the present invention is to provide a base station energy storage device and a control method thereof to solve the technical problems in the prior art that the base station needs to be modified, the construction is difficult, the energy storage coverage is not high, and anti-islanding protection measures are required when the power grid is out of power. The specific scheme is as follows:

[0008] In order to solve the above technical problems, the present invention provides a base station energy storage device, which is connected in series to the AC bus of the power grid, and the base station energy storage device includes: a power supply module for powering a controller, a detection module for detecting the power supply state of the power grid, a first switch, a second switch, a third switch, a rectifier, an inverter, an energy storage device, a charging power supply for controlling the charging and discharging state of the energy storage device, and a controller for controlling the charging and discharging state of the energy storage device according to the operating state and electricity price of the power grid, and switching the power supply source of the inverter, so as to use the inverter to power the base station;

[0009] The detection module is connected to the controller through the second switch and the third switch connected in series, the control end of the second switch is used to receive the output signal of the detection module, the detection module is connected to the input end of the rectifier through the first switch, the output end of the rectifier is connected to the inverter, and the output end of the energy storage device is connected to the inverter.

[0010] Preferably, the charging power supply is specifically an AC / DC conversion module or a DC / DC conversion module.

[0011] Preferably, the rectifier is connected to the inverter via a first controllable switch and a first diode, and the energy storage device is connected to the inverter via a second controllable switch and a second diode;

[0012] Among them, the output end of the rectifier is respectively connected to the first end of the first controllable switch and the positive electrode of the first diode, the second end of the first controllable switch is respectively connected to the inverter and the negative electrode of the first diode, the first end of the second controllable switch is respectively connected to the energy storage device and the positive electrode of the second diode, the second end of the second controllable switch is respectively connected to the inverter and the negative electrode of the second diode, and the control end of the first controllable switch and the control end of the second controllable switch are both used to receive the control signal output by the controller.

[0013] Preferably, it further comprises: a photovoltaic device, a third controllable switch and a third diode;

[0014] Among them, the first end of the third controllable switch is respectively connected to the photovoltaic device and the positive electrode of the third diode, the second end of the third controllable switch is respectively connected to the negative electrode of the third diode and the inverter, and the control end of the third controllable switch is used to receive the control signal output by the controller.

[0015] Preferably, the detection module includes: a fourth diode, a fifth diode, a sixth diode, a seventh diode, a first capacitor, a second capacitor, a first resistor, a second resistor and an optical coupler;

[0016] Wherein, the anode of the fourth diode is connected to the cathode of the sixth diode, the cathode of the fourth diode is respectively connected to the cathode of the fifth diode, the first end of the first capacitor and the first end of the first resistor, the anode of the fifth diode is connected to the cathode of the seventh diode, the anode of the seventh diode is respectively connected to the anode of the sixth diode, the second end of the first capacitor and the second end of the optocoupler, the second end of the first resistor is connected to the first end of the optocoupler, the third end of the optocoupler is connected to the first end of the second capacitor, the third end of the optocoupler is grounded, the fourth end of the optocoupler is connected to the first end of the second resistor, the second end of the second resistor is connected to VCC, and the second end of the second capacitor is connected to the first end of the second resistor;

[0017] Correspondingly, the anode of the fourth diode and the cathode of the seventh diode are input terminals of the detection module, and the first terminal of the second resistor is the output terminal of the detection module.

[0018] In order to solve the above technical problems, the present invention further provides a control method for a base station energy storage device, which is applied to a controller in a base station energy storage device disclosed above, comprising:

[0019] The charging and discharging state of the energy storage device is controlled according to the operation state of the power grid and the electricity price, and the power supply source of the inverter is switched to utilize the inverter to supply power to the base station.

[0020] Preferably, the controlling the charging and discharging state of the energy storage device according to the operating state and electricity price of the power grid and switching the power supply source of the inverter to use the inverter to power the base station includes:

[0021] When the power grid operates normally, if the electricity price of the power grid is lower than a first preset threshold, the first switch is controlled to be turned on, and the charging power supply is controlled to charge the energy storage device, and the rectifier is controlled to supply power to the inverter, so as to use the inverter to supply power to the base station;

[0022] When the power grid operates normally, if the electricity price of the power grid is higher than a second preset threshold, the third switch is controlled to be turned off to turn off the first switch, and the energy storage device is controlled to supply power to the inverter, so as to use the inverter to supply power to the base station;

[0023] When the power grid loses power, the detection module controls the second switch to turn off, so as to turn off the first switch, and controls the energy storage device to supply power to the inverter, so as to use the inverter to supply power to the base station;

[0024] When the power grid operates normally, the detection module controls the second switch to be turned on to turn on the first switch, and controls the rectifier to supply power to the inverter, so as to use the inverter to supply power to the base station.

[0025] Preferably, it also includes:

[0026] When it is detected that the power level of the energy storage device is lower than a preset power replenishment threshold, the charging power source is controlled to charge the energy storage device.

[0027] Preferably, it also includes:

[0028] When it is detected that the amount of electricity in the process of the energy storage device supplying power to the inverter is lower than a preset discharge threshold, the second switch and the third switch are controlled to be turned on, the energy storage device is stopped from supplying power to the inverter, and the rectifier is used to supply power to the inverter, so that the inverter is used to supply power to the base station.

[0029] Preferably, it also includes:

[0030] During the process of the energy storage device supplying power to the inverter, the designated equipment in the base station is controlled to be powered off; wherein the designated equipment is a device divided according to the importance of each device in the base station.

[0031] Beneficial effect: In a base station energy storage device provided by the present invention, because the base station energy storage device is connected in series to the AC busbar of the power grid, there is no need to modify the base station, so this setting method can reduce the difficulty of installing the base station energy storage device at the construction site. At the same time, the base station energy storage device supplies power to the base station through its internal inverter, and there is no need to track the frequency and phase of the power grid. The logic is simple, and the base station energy storage device can simultaneously supply power to the AC equipment and DC equipment in the base station. Its output power can cover all equipment in the base station, and the energy storage coverage rate is high. In addition, when the detection module in the base station energy storage device detects that the power grid is off, it will send the signal to the controller. At this time, the controller will control the first switch to turn off. In this case, the base station energy storage device is disconnected from the power grid and is in an island operation mode. There is no need to take additional island protection measures for the base station energy storage device, thereby further improving the overall reliability of the base station energy storage device during operation.

[0032] Correspondingly, a control method for a base station energy storage device provided by the present invention also has the above-mentioned beneficial effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0034] Figure 1 A schematic diagram of realizing the integrated application of base station energy storage by means of a switching power supply;

[0035] Figure 2 A schematic diagram of realizing the integrated application of base station energy storage by using smart lithium batteries;

[0036] Figure 3 A schematic diagram of realizing the integrated application of base station energy storage by means of time-controlled switches;

[0037] Figure 4 A schematic diagram of realizing the integrated application of base station energy storage by connecting energy storage equipment in parallel on the AC bus side of the power grid;

[0038] Figure 5 A structural diagram of a base station energy storage device provided by an embodiment of the present invention;

[0039] Figure 6 This is a schematic diagram of the working mode of the base station energy storage device;

[0040] Figure 7This is a structural diagram when the charging power source in the base station energy storage device is set as an AC / DC conversion module;

[0041] Figure 8 This is a structural diagram when the charging power supply in the base station energy storage device is set as a DC / DC conversion module;

[0042] Fig. 9 A structural diagram of another base station energy storage device provided by an embodiment of the present invention;

[0043] Fig.10 This is a schematic diagram of the principle of using a rectifier and an energy storage device to power an inverter;

[0044] Fig.11 This is a schematic diagram of the principle of using a rectifier, an energy storage device and a photovoltaic device to power an inverter;

[0045] Fig.12 A structural diagram of a detection module provided by an embodiment of the present invention;

[0046] Fig.13 A flow chart of a control method for a base station energy storage device provided by an embodiment of the present invention;

[0047] Fig.14 This is a flow chart of another method for controlling a base station energy storage device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0048] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0049] See also Figure 5 , Figure 5 A structural diagram of a base station energy storage device provided in an embodiment of the present invention, the base station energy storage device is connected in series to the AC bus of the power grid, and the base station energy storage device includes: a power supply module 11 for powering a controller 17, a detection module 12 for detecting the power supply status of the power grid, a first switch S1, a second switch S2, a third switch S3, a rectifier 13, an inverter 14, an energy storage device 15, a charging power supply 16 for controlling the charge and discharge status of the energy storage device 15, and a controller 17 for controlling the charge and discharge status of the energy storage device 15 according to the operating status and electricity price of the power grid, and switching the power supply source of the inverter 14 to use the inverter 14 to power the base station;

[0050] Among them, the detection module 12 is connected to the controller 17 through a second switch S2 and a third switch S3 connected in series, the control end of the second switch S2 is used to receive the output signal of the detection module 12, the detection module 12 is connected to the input end of the rectifier 13 through the first switch S1, the output end of the rectifier 13 is connected to the inverter 14, and the output end of the energy storage device 15 is connected to the inverter 14.

[0051] In this embodiment, a base station energy storage device is provided, which is connected in series to the AC bus of the power grid, that is, the base station energy storage device is connected in series between the power grid and the base station, its AC input line is connected to the power grid, and its AC output line is connected to the base station.

[0052] Since the base station energy storage equipment is connected in series to the AC busbar of the power grid, there is no need to modify the base station. Therefore, when the base station energy storage equipment is to be installed at the construction site, it can be directly connected in series between the power grid and the base station. This can greatly reduce the difficulty of installing the base station energy storage equipment at the construction site. When installing the base station energy storage equipment, the base station energy storage equipment can be installed either outside the base station plant or inside the base station plant.

[0053] It should be noted that in the present application, the on-off state of the first switch S1 will be affected by the on-off state of the second switch S2 and the third switch S3. If any one of the second switch S2 and the third switch S3 is in an off-circuit state, the first switch S1 will be in an off-circuit state. For example: in some specific embodiments, the first switch S1 can be set as a relay or a contactor, then the circuit formed by the second switch S2 and the third switch S3 is the control circuit of the coil set on the relay or the contactor. If any one of the second switch S2 and the third switch S3 is disconnected, the power supply source of the coil on the relay or the contactor can be disconnected, thereby achieving the purpose of turning off the relay or the contactor (the first switch S1). Figure 5 In the figure, the part of the base station energy storage device enclosed by a dotted line represents a relay or a contactor, and the device shown above S1 represents a coil in the relay or the contactor.

[0054] The on / off state of the third switch S3 is controlled by the controller 17, and the on / off state of the second switch S2 is controlled by the detection module 12. That is, when the detection module 12 detects that the power grid is in a power-off state, the second switch S2 is in an open circuit state, and when the detection module 12 detects that the power grid is in a normal operating state, the second switch S2 is in an on state. In addition, in practical applications, the power supply module 11 can be set to a cascade structure of multiple AC / DC conversion modules.

[0055] When the detection module 12 detects that the power grid is operating normally, the controller 17 in the base station energy storage device will control the energy storage device 15 to charge or discharge according to the power price of the power grid to improve the economic benefits of the base station energy storage device. Specifically, when the power price of the power grid is lower than the first preset threshold, it means that the power grid is in a valley period or a normal period, and the power price is low. At this time, the first switch S1 is in the on state, and the controller 17 will control the charging power supply 16 to charge the energy storage device 15 until the energy storage device 15 is fully charged. In this process, the rectifier 13 will rectify the electric energy output by the power grid, and the high-voltage direct current output by the rectifier 13 will be input into the inverter 14. At this time, the controller 17 will control the inverter 14 to supply power to various devices in the base station. When the electricity price of the power grid is higher than the second preset threshold, it means that the power grid is in a peak period or a peak period, and the electricity price is high. At this time, the controller 17 will turn off the third switch S3, and the first switch S1 is also in the off state. At this time, the rectifier 13 is powered off, and the energy storage device 15 provides power to the inverter 14. The inverter 14 will convert the power of the energy storage device 15 into three-phase alternating current and power each device in the base station.

[0056] Since this control method enables the base station energy storage device to supply power to all devices within the base station, its output power can cover all devices within the base station, thereby improving the coverage rate of the base station energy storage device when supplying power to various devices within the base station and significantly improving the economic benefits of the base station energy storage device.

[0057] When the detection module 12 detects that the power grid is powered off, the detection module 12 will send a corresponding control signal to the controller 17, and the detection module 12 will also turn off the second switch S2. After the second switch S2 is turned off, the first switch S1 is also in an open circuit state. At this time, the rectifier 13 is powered off, and the energy storage device 15 provides power to the inverter 14. After the inverter 14 converts the power output by the energy storage device 15 into three-phase alternating current, the inverter 14 will supply power to various devices in the base station.

[0058] In this case, the base station energy storage device is disconnected from the power grid and is in an island operation mode. There is no need to take additional island protection measures for the base station energy storage device. It is completely controlled by hardware and does not require the intervention of software programs. This can further improve the overall reliability of the base station energy storage device during operation.

[0059] When the detection module 12 detects that the power grid has resumed power supply, the detection module 12 will turn on the second switch S2. After the second switch S2 is turned on, the first switch S1 is also in the on state, and the rectifier 13 will rectify the power output by the power grid, and the inverter 14 will convert the high-voltage direct current output by the rectifier 13 into three-phase alternating current, and supply power to various devices in the base station.

[0060] See also Figure 6 , Figure 6 The diagram is a working mode diagram of the base station energy storage device. When the power grid is operating normally, if the power grid is in a valley period or a normal period, the energy storage device is in a charging state. If the power grid is in a peak period or a peak period, the energy storage device is in a discharging state. In this case, the entire system of the base station energy storage device will be in an energy storage mode. When the power grid is in a power-off state, the energy storage device is in a discharging state. In this case, the entire system of the base station energy storage device will be in a backup power mode.

[0061] In addition, when using the base station energy storage device provided in the present application to store energy and provide backup power for the base station, there is no need to install a backup battery for the base station. The power stored in the energy storage device in the base station energy storage device can be directly used to provide backup power for each device in the base station. This can further reduce the cost investment in the integration of base station energy storage.

[0062] In a base station energy storage device provided in this embodiment, because the base station energy storage device is connected in series to the AC busbar of the power grid, there is no need to modify the base station, so this setting method can reduce the difficulty of installing the base station energy storage device at the construction site. At the same time, the base station energy storage device supplies power to the base station through its internal inverter, and there is no need to track the frequency and phase of the power grid. The logic is simple, and the base station energy storage device can simultaneously supply power to the AC equipment and DC equipment in the base station. Its output power can cover all equipment in the base station, and the energy storage coverage rate is high. In addition, when the detection module in the base station energy storage device detects that the power grid is off, it will send the signal to the controller. At this time, the controller will control the first switch to turn off. In this case, the base station energy storage device is disconnected from the power grid and is in an island operation mode. There is no need to take additional island protection measures for the base station energy storage device, thereby further improving the overall reliability of the base station energy storage device during operation.

[0063] Based on the above embodiments, this embodiment further illustrates and optimizes the technical solution. As a preferred implementation, the charging power source 16 is specifically an AC / DC conversion module 161 or a DC / DC conversion module 162 .

[0064] In this embodiment, the charging power source 16 can be configured as either an AC / DC conversion module 161 or a DC / DC conversion module 162. Figure 7 and Figure 8 , Figure 7 This is a structural diagram when the charging power source 16 in the base station energy storage device is set as an AC / DC conversion module. Figure 8 This is a structural diagram when the charging power source 16 in the base station energy storage device is set as a DC / DC conversion module.

[0065] When the charging power source 16 is set to an AC / DC conversion module 161, the AC / DC conversion module 161 needs to be connected to the rear end of the first switch S1, so that the AC / DC conversion module 161 can be used to convert the electric energy output by the power grid into alternating current, and the AC / DC conversion module 161 can be used to power the energy storage device. When the charging power source 16 is set to a DC / DC conversion module 162, the DC / DC conversion module 162 needs to be connected to the rear end of the rectifier, so that the DC / DC conversion module 162 can be used to convert the direct current output by the rectifier into direct current, and the DC / DC conversion module 162 can be used to power the energy storage device.

[0066] It should be noted that, in actual applications, an off-grid indicator D0 for displaying the on-off state of the first switch S1 can also be connected to the controller 17, and the off-grid indicator D0 can be used to represent the grid-connected state or off-grid state of the base station energy storage device and the power grid. Specifically, when the first switch S1 is in the on state, the base station energy storage device and the power grid are in the grid-connected state, and when the first switch S1 is in the off state, the base station energy storage device and the power grid are in the off-grid state. Obviously, by connecting the on-grid and off-grid indicator D0 to the controller 17, the staff can clearly and intuitively view the real-time operating status of the power grid.

[0067] Obviously, the technical solution provided in this embodiment can ensure the flexibility and diversity of the charging power supply setting method.

[0068] Based on the above embodiments, this embodiment further illustrates and optimizes the technical solution. Fig. 9 , Fig. 9 A structural diagram of another base station energy storage device provided by an embodiment of the present invention. As a preferred implementation, the rectifier 13 is connected to the inverter 14 via the first controllable switch Q1 and the first diode D1, and the energy storage device 15 is connected to the inverter 14 via the second controllable switch Q2 and the second diode D2;

[0069] Among them, the output end of the rectifier 13 is respectively connected to the first end of the first controllable switch Q1 and the positive electrode of the first diode D1, the second end of the first controllable switch Q1 is respectively connected to the input end of the inverter 14 and the negative electrode of the first diode D1, the first end of the second controllable switch Q2 is respectively connected to the energy storage device 15 and the positive electrode of the second diode D2, the second end of the second controllable switch Q2 is respectively connected to the input end of the inverter 14 and the negative electrode of the second diode D2, and the control end of the first controllable switch Q1 and the control end of the second controllable switch Q2 are both used to receive the control signal output by the controller 17.

[0070] See also Fig.10 , Fig.10 This is a schematic diagram of the principle of using a rectifier and an energy storage device to power the inverter. Fig.10 Inverter 14 has two DC input channels. When the power grid operates normally, rectifier 13 supplies power to inverter 14. At this time, first controllable switch Q1 is turned on and second controllable switch Q2 is turned off. When inverter 14 converts the DC power output by rectifier 13 into three-phase AC power, inverter 14 can supply power to various devices in the base station.

[0071] When the grid loses power, or the energy storage device 15 needs to be discharged, the first controllable switch Q1 is disconnected, the grid cannot provide power to the rectifier 13, and the rectifier 13 stops outputting DC. At this time, due to the presence of the second diode D2 on the second controllable switch Q2, the energy storage device 15 will immediately supply power to the inverter 14. In this case, the power supply source of the inverter 14 is changed from the rectifier 13 to the energy storage device 15. When the inverter 14 converts the power of the energy storage device 15 into three-phase AC power, the inverter 14 can supply power to various devices in the base station.

[0072] When the power grid operates normally, the detection module controls the second controllable switch Q2 to be turned on, and the first controllable switch Q1 is also in the on state, and the power supply source of the inverter 14 is changed from the energy storage device 15 to the rectifier 13 again. When the inverter 14 converts the direct current output by the rectifier 13 into three-phase alternating current, the inverter 14 can supply power to various devices in the base station.

[0073] Obviously, through the technical solution provided in this embodiment, seamless switching of the inverter power supply source can be achieved in different application scenarios.

[0074] See also Fig. 9 , Fig. 9 This is a structural diagram of another base station energy storage device provided by an embodiment of the present invention. As a preferred implementation, the base station energy storage device further includes: a photovoltaic device 18, a third controllable switch Q3 and a third diode D3;

[0075] Among them, the first end of the third controllable switch Q3 is respectively connected to the photovoltaic device 18 and the positive electrode of the third diode D3, the second end of the third controllable switch Q3 is respectively connected to the negative electrode of the third diode D3 and the input end of the inverter 14, and the control end of the third controllable switch Q3 is used to receive the control signal output by the controller.

[0076] In practical applications, a photovoltaic device 18 may be provided in the base station energy storage device, and the photovoltaic device 18 may be used to increase the power supply source of the inverter 14, so as to further improve the utilization rate of energy and increase the economic benefits of the base station energy storage device.

[0077] See also Fig.11 , Fig.11The schematic diagram is a principle diagram of using a rectifier, an energy storage device and a photovoltaic device to power the inverter. When the power grid loses power, the first controllable switch Q1 is disconnected, the power grid cannot provide power to the rectifier 13, and the rectifier 13 stops outputting DC. At this time, due to the presence of the third diode D3 on the third controllable switch Q3, the photovoltaic device 18 will immediately supply power to the inverter 14. In this case, the power supply source of the inverter 14 is changed from the rectifier 13 to the photovoltaic device 18. When the inverter 14 converts the power of the photovoltaic device 18 into three-phase AC power, the inverter 14 can supply power to various devices in the base station.

[0078] Obviously, the technical solution provided by this embodiment can not only increase the power supply source of the inverter, but also improve the utilization rate of energy and increase the economic benefits of the base station energy storage equipment.

[0079] Based on the above embodiments, this embodiment further illustrates and optimizes the technical solution. Fig.12 , Fig.12 A structural diagram of a detection module provided by an embodiment of the present invention. As a preferred implementation, the detection module 12 includes: a fourth diode D4, a fifth diode D5, a sixth diode D6, a seventh diode D7, a first capacitor C1, a second capacitor C2, a first resistor R1, a second resistor R2 and an optical coupler U;

[0080] Wherein, the anode of the fourth diode D4 is connected to the cathode of the sixth diode D6, the cathode of the fourth diode D4 is respectively connected to the cathode of the fifth diode D5, the first end of the first capacitor C1 and the first end of the first resistor R1, the anode of the fifth diode D5 is connected to the cathode of the seventh diode D7, the anode of the seventh diode D7 is respectively connected to the anode of the sixth diode D6, the second end of the first capacitor C1 and the second end of the optical coupler U, the second end of the first resistor R1 is connected to the first end of the optical coupler U, the third end of the optical coupler U is connected to the first end of the second capacitor C2, the third end of the optical coupler U is grounded, the fourth end of the optical coupler U is connected to the first end of the second resistor R2, the second end of the second resistor R2 is connected to VCC, and the second end of the second capacitor C2 is connected to the first end of the second resistor R2;

[0081] Correspondingly, the anode of the fourth diode D4 and the cathode of the seventh diode D7 are input terminals of the detection module 12 , and the first terminal of the second resistor R2 is the output terminal of the detection module 12 .

[0082] In this embodiment, the hardware structure of the detection module 12 is specifically described. In the detection module 12, the first resistor R1 is a voltage-dividing resistor. The detection module 12 mainly detects the power supply status of the power grid through the optical coupler U.

[0083] Specifically, when the power grid has electricity, the optical coupler U is in the on state, and when the power grid loses power, the optical coupler U is in the off state. The on state or off state of the optical coupler U will change the voltage value at the first end of the resistor R2. Therefore, by detecting the voltage value at the first end of the second resistor R2, it can be determined whether the power grid has lost power according to the detection result. When it is determined that the power grid has lost power according to the voltage value at the first end of the second resistor R2, the second switch S2 is in the off state, and the first switch S1 is also in the off state. Under this setting mode, by detecting the voltage value at the first end of the second resistor R2, the detection of the power supply state of the power grid can be realized using a pure hardware method. Compared with the method of using software to detect the power supply state of the power grid, the judgment result of the detection module 12 will be more accurate and timely.

[0084] Furthermore, when this method is used to detect the power supply status of the power grid, since the photoelectric effect of the optical coupling module can be used to isolate the electrical signal from the optical signal, this method can further ensure the accuracy and reliability of the detection result of the detection module 12.

[0085] Obviously, through the technical solution provided by this embodiment, the operating status of the power grid can be accurately detected.

[0086] Correspondingly, an embodiment of the present invention further provides a control method for a base station energy storage device, the control method being applied to a controller in a base station energy storage device disclosed above, the control method comprising:

[0087] The charging and discharging state of the energy storage device is controlled according to the operating state of the power grid and the electricity price, and the power supply source of the inverter is switched to use the inverter to power the base station.

[0088] The control method of a base station energy storage device provided in this embodiment can refer to the contents disclosed in the above embodiments, and will not be described in detail here.

[0089] A control method for a base station energy storage device provided in an embodiment of the present invention has the beneficial effects of the base station energy storage device provided in the above-mentioned embodiment.

[0090] Based on the above embodiments, this embodiment further illustrates and optimizes the technical solution. Fig.13 , Fig.13 A flowchart of a control method for a base station energy storage device provided by an embodiment of the present invention. As a preferred implementation, the above steps: controlling the charge and discharge state of the energy storage device according to the operation state and electricity price of the power grid, and switching the power supply source of the inverter to use the inverter to power the base station, include:

[0091] Step S11: when the power grid is operating normally, if the power price of the power grid is lower than a first preset threshold, the first switch is controlled to be turned on, and the charging power supply is controlled to charge the energy storage device, and the rectifier is controlled to supply power to the inverter, so as to use the inverter to supply power to the base station;

[0092] Step S12: when the power grid operates normally, if the power price of the power grid is higher than the second preset threshold, the third switch is controlled to be turned off to turn off the first switch, and the energy storage device is controlled to supply power to the inverter, so as to use the inverter to supply power to the base station;

[0093] Step S13: When the power grid loses power, the detection module controls the second switch to turn off, so as to turn off the first switch, and controls the energy storage device to supply power to the inverter, so as to use the inverter to supply power to the base station;

[0094] Step S14: when the power grid operates normally, the detection module controls the second switch to be turned on, so as to turn on the first switch, and controls the rectifier to supply power to the inverter, so as to use the inverter to supply power to the base station.

[0095] In this embodiment, when the power grid is operating normally, if the power price of the power grid is lower than the first preset threshold value, it means that the power grid is in a normal period or a valley period at this time, and the power price is low. At this time, in order to improve the economic benefits of the base station energy storage equipment, it is necessary to use the energy storage device to store electric energy, and wait until the power price of the power grid is higher, and use the electric energy in the energy storage device to power the base station. In this case, the controller can turn on the first switch and control the charging power supply to charge the energy storage device until the energy storage device is fully charged. At the same time, the rectifier will rectify the AC power output by the power grid, and input the rectified high-voltage DC power into the inverter, and the inverter will supply power to the base station under the action of the controller.

[0096] When the power grid is operating normally, if the power price of the power grid is higher than the second preset threshold, it means that the power grid is in a peak period or a peak period, and the power price is high. At this time, in order to improve the economic benefits of the base station energy storage equipment, it is necessary to stop charging the energy storage device and use the electric energy stored in the energy storage device to power the base station. Specifically, at this time, the controller will turn off the third switch to achieve the purpose of turning off the first switch. When the first switch is in an off-circuit state, the base station energy storage device and the power grid are in an off-grid state, and the rectifier is powered off. At this time, the power supply source of the inverter is converted from the rectifier to the energy storage device. The controller will control the energy storage device to supply power to the inverter, and use the three-phase current output by the inverter after inverting the energy storage device to power the base station.

[0097] When the power grid is in a power-off state, the detection module will detect the power-off state of the power grid. At this time, the second switch will be in an open circuit state under the triggering action of the detection module, thereby causing the first switch to be in an open circuit state. At this time, the base station energy storage device and the power grid are in an off-grid state. In this case, the controller will control the energy storage device to supply power to the inverter, and use the three-phase current output by the inverter after inverting the energy storage device to power the base station.

[0098] When the power grid is in normal operation, the detection module will detect the normal operation of the power grid, and the detection module will control the second switch to be turned on. When the second switch is in the on state, the first switch will also be in the on state. In this case, the base station energy storage device is in a grid-connected state with the power grid, and the rectifier can rectify the electric energy output by the power grid, and use the rectified DC power to power the inverter. After the inverter converts the high-voltage DC power output by the rectifier into three-phase AC power, it can power the base station.

[0099] Obviously, the technical solution provided in this embodiment can not only improve the economic benefits of the base station energy storage equipment, but also, when the power grid loses power, the base station energy storage equipment is automatically disconnected from the grid and is in an island operation mode, which can further improve the safety and reliability of the base station energy storage equipment during operation.

[0100] Based on the above embodiment, this embodiment further illustrates and optimizes the technical solution. As a preferred implementation, the above control method further includes:

[0101] When it is detected that the power level of the energy storage device is lower than a preset power replenishment threshold, the charging power supply is controlled to charge the energy storage device.

[0102] In this embodiment, if the controller detects that the power of the energy storage device is lower than the preset power replenishment threshold, it means that the power in the energy storage device is very low and cannot achieve the purpose of backing up the base station. At this time, no matter what the power price of the power grid is, the controller will control the charging power supply to charge the energy storage device. That is, no matter whether the power price of the power grid is in the peak period, valley period, or normal period, as long as the power grid is in normal operation, the controller will control the charging power supply to charge the energy storage device.

[0103] Obviously, the technical solution provided in this embodiment can ensure that the energy storage device in the base station energy storage device can stably and reliably supply power to the base station when the power grid fails.

[0104] Based on the above embodiment, this embodiment further illustrates and optimizes the technical solution. As a preferred implementation, the above control method further includes:

[0105] When it is detected that the amount of electricity in the process of the energy storage device supplying power to the inverter is lower than the preset discharge threshold, the second switch and the third switch are controlled to be turned on, the energy storage device is stopped from supplying power to the inverter, and the rectifier is used to supply power to the inverter, so that the inverter can supply power to the base station.

[0106] In this embodiment, when the controller detects that the amount of electricity in the energy storage device supplying power to the inverter is lower than the preset discharge threshold, it means that the amount of electricity in the energy storage device is low and can no longer provide sufficient backup time for the base station. At this time, the controller will control the second switch and the third switch to be turned on to turn on the first switch and switch the power supply source of the inverter from the energy storage device to the rectifier. When the inverter converts the high-voltage direct current output by the rectifier into three-phase alternating current, the three-phase alternating current output by the inverter can be used to power the base station.

[0107] It should be noted that the preset power replenishment threshold and the preset discharge threshold are both numerical values ​​pre-set according to the amount of electricity stored in the energy storage device. The preset power replenishment threshold usually refers to the minimum storage capacity of the energy storage device. The preset discharge threshold refers to the amount of electricity that the energy storage device can provide to the base station when the energy storage device is at least able to provide a preset fractional power supply in order to meet the power outage scenario of the power grid. Both the preset power replenishment threshold and the preset discharge threshold can be adaptively adjusted according to different actual scenarios. The preset power replenishment threshold and the preset discharge threshold can be adjusted by local operation or by remote operation.

[0108] Obviously, through the technical solution provided in this embodiment, the overall reliability of the base station energy storage device when supplying power to the base station can be further guaranteed.

[0109] Based on the above embodiment, this embodiment further illustrates and optimizes the technical solution. As a preferred implementation, the above control method further includes:

[0110] During the process of the energy storage device supplying power to the inverter, the designated equipment in the base station is controlled to be powered off; wherein the designated equipment is equipment divided according to the importance of each equipment in the base station.

[0111] In actual applications, if classified according to their importance, the devices in the base station can also be divided into different levels. For example, the BBU (Baseband Unit) and RFU (Radio Frequency Unit) in the base station are important devices, while the air conditioner, lighting and other equipment in the base station are unimportant equipment. Even if these devices are turned off, it will not affect the normal operation of the base station.

[0112] When the energy storage device supplies power to the inverter, it means that the power grid is in a power-off state or the power price of the power grid is high. In this process, in order to improve the economic benefits of the base station energy storage equipment, the controller can also communicate with the equipment in the base station and control the power off of designated equipment in the base station, such as: power off the air conditioner and lighting equipment in the base station to reduce the number of base station power supply equipment provided by the energy storage device, thereby extending the time the energy storage device supplies power to the base station.

[0113] Obviously, the technical solution provided by this embodiment can further improve the economic benefits of base station energy storage equipment.

[0114] In order to enable those skilled in the art to more clearly understand the implementation principle of the present application, the above disclosed technical content is described in detail here through an application scenario embodiment. Fig.14 , Fig.14 This is a flow chart of another method for controlling a base station energy storage device provided by an embodiment of the present invention.

[0115] Combination Fig. 9 The base station energy storage device shown, when using the base station energy storage device to power the base station, first detects whether the power grid is operating normally. When the power grid is in a power-off state, it means that the base station energy storage device needs to work in the backup power mode. At this time, Q2 is turned on, and the energy storage device is used to power the inverter, so as to use the inverter to power the base station. In this process, it is necessary to determine in real time whether the energy storage device is empty. If the energy storage device is in an empty state, the process ends. If the energy storage device is not in an empty state, continue to enter the step of detecting whether the power grid is operating normally.

[0116] If the power grid is in normal operation, it is determined whether the power level of the energy storage device is lower than the preset power replenishment threshold. If the power level of the energy storage device is lower than the preset power replenishment threshold, it means that the power level in the energy storage device is very low and cannot achieve the purpose of backing up the base station. At this time, the charging power supply is directly controlled to charge the energy storage device, and the steps of determining whether the power grid is operating normally are continued.

[0117] If the power of the energy storage device is higher than the preset power replenishment threshold, it is determined whether the power grid is in normal period or off-peak period. If the power grid is in normal period or off-peak period, it means that the power grid electricity price is low. In order to improve the economic benefits of the base station energy storage equipment, the charging power supply is controlled to charge the energy storage device at this time, and the steps of determining whether the power grid is operating normally are continued.

[0118] If the power grid is not in a normal period or a valley period, then determine whether the power grid is in a peak period or a peak period. If the power grid is in a peak period or a peak period, it means that the power grid electricity price is high. In order to improve the economic benefits of the base station energy storage equipment, S3 is disconnected to disconnect S1, Q2 is turned on, and the energy storage device is used to power the inverter, so as to use the inverter to power the base station. In this process, it is also necessary to determine whether the power of the energy storage device is lower than the preset discharge threshold. If so, it means that the power in the energy storage device is small and can no longer provide sufficient backup time for the base station. At this time, S3 is closed to turn on S1, turn off Q2, control the energy storage device to stop discharging, and use the rectifier to power the inverter, and use the inverter to power the base station; if not, continue to perform the steps of determining whether the power grid is operating normally.

[0119] Obviously, through the technical solution provided in this embodiment, no matter what operation mode the power grid is in, it can ensure that the base station energy storage device can provide stable and reliable power supply to the base station.

[0120] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0121] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0122] The above is a detailed introduction to a base station energy storage device and a control method thereof provided by the present invention. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea; at the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A base station energy storage device, characterized in that: The base station energy storage device is connected in series to the AC bus of the power grid, and includes: a power supply module for supplying power to a controller, a detection module for detecting the power supply status of the power grid, a first switch, a second switch, a third switch, a rectifier, an inverter, an energy storage device, a charging power supply for controlling the charge and discharge status of the energy storage device, and a controller for controlling the charge and discharge status of the energy storage device according to the operating status and electricity price of the power grid, and switching the power supply source of the inverter, so as to use the inverter to supply power to the base station; The detection module is connected to the controller through the second switch and the third switch connected in series, the control end of the second switch is used to receive the output signal of the detection module, the detection module is connected to the input end of the rectifier through the first switch, the output end of the rectifier is connected to the inverter, and the output end of the energy storage device is connected to the inverter.

2. A base station energy storage device according to claim 1, characterized in that: The charging power source is specifically an AC / DC conversion module or a DC / DC conversion module.

3. A base station energy storage device according to claim 1, characterized in that: The rectifier is connected to the inverter via a first controllable switch and a first diode, and the energy storage device is connected to the inverter via a second controllable switch and a second diode; Among them, the output end of the rectifier is respectively connected to the first end of the first controllable switch and the positive electrode of the first diode, the second end of the first controllable switch is respectively connected to the inverter and the negative electrode of the first diode, the first end of the second controllable switch is respectively connected to the energy storage device and the positive electrode of the second diode, the second end of the second controllable switch is respectively connected to the inverter and the negative electrode of the second diode, and the control end of the first controllable switch and the control end of the second controllable switch are both used to receive the control signal output by the controller.

4. A base station energy storage device according to claim 3, characterized in that: Also includes: a photovoltaic device, a third controllable switch, and a third diode; Among them, the first end of the third controllable switch is respectively connected to the photovoltaic device and the positive electrode of the third diode, the second end of the third controllable switch is respectively connected to the negative electrode of the third diode and the inverter, and the control end of the third controllable switch is used to receive the control signal output by the controller.

5. A base station energy storage device according to claim 1, characterized in that: The detection module includes: a fourth diode, a fifth diode, a sixth diode, a seventh diode, a first capacitor, a second capacitor, a first resistor, a second resistor and an optical coupler; Wherein, the anode of the fourth diode is connected to the cathode of the sixth diode, the cathode of the fourth diode is respectively connected to the cathode of the fifth diode, the first end of the first capacitor and the first end of the first resistor, the anode of the fifth diode is connected to the cathode of the seventh diode, the anode of the seventh diode is respectively connected to the anode of the sixth diode, the second end of the first capacitor and the second end of the optocoupler, the second end of the first resistor is connected to the first end of the optocoupler, the third end of the optocoupler is connected to the first end of the second capacitor, the third end of the optocoupler is grounded, the fourth end of the optocoupler is connected to the first end of the second resistor, the second end of the second resistor is connected to VCC, and the second end of the second capacitor is connected to the first end of the second resistor; Correspondingly, the anode of the fourth diode and the cathode of the seventh diode are input terminals of the detection module, and the first terminal of the second resistor is the output terminal of the detection module.

6. A control method for a base station energy storage device, characterized in that: A controller used in a base station energy storage device according to any one of claims 1 to 5, comprising: The charging and discharging state of the energy storage device is controlled according to the operation state of the power grid and the electricity price, and the power supply source of the inverter is switched to utilize the inverter to supply power to the base station.

7. A control method for a base station energy storage device according to claim 6, characterized in that: The method controls the charging and discharging state of the energy storage device according to the operation state of the power grid and the electricity price, and switches the power supply source of the inverter so as to use the inverter to power the base station, including: When the power grid operates normally, if the electricity price of the power grid is lower than a first preset threshold, the first switch is controlled to be turned on, and the charging power supply is controlled to charge the energy storage device, and the rectifier is controlled to supply power to the inverter, so as to use the inverter to supply power to the base station; When the power grid operates normally, if the electricity price of the power grid is higher than a second preset threshold, the third switch is controlled to be turned off to turn off the first switch, and the energy storage device is controlled to supply power to the inverter, so as to use the inverter to supply power to the base station; When the power grid loses power, the detection module controls the second switch to turn off, so as to turn off the first switch, and controls the energy storage device to supply power to the inverter, so as to use the inverter to supply power to the base station; When the power grid operates normally, the detection module controls the second switch to be turned on to turn on the first switch, and controls the rectifier to supply power to the inverter, so as to use the inverter to supply power to the base station.

8. A control method for a base station energy storage device according to claim 7, characterized in that: Also includes: When it is detected that the power level of the energy storage device is lower than a preset power replenishment threshold, the charging power source is controlled to charge the energy storage device.

9. A control method for a base station energy storage device according to claim 7, characterized in that: Also includes: When it is detected that the amount of electricity in the process of the energy storage device supplying power to the inverter is lower than a preset discharge threshold, the second switch and the third switch are controlled to be turned on, the energy storage device is stopped from supplying power to the inverter, and the rectifier is used to supply power to the inverter, so that the inverter is used to supply power to the base station.

10. A control method for a base station energy storage device according to claim 7, characterized in that: Also includes: During the process of the energy storage device supplying power to the inverter, the designated equipment in the base station is controlled to be powered off; wherein the designated equipment is a device divided according to the importance of each device in the base station.

Images