Power grid frequency modulation method and system based on supercapacitor

Abstract

The invention is suitable for the technical field of power grid frequency modulation, and provides a power grid frequency modulation method and system based on a super capacitor, and the method comprises the steps: detecting the voltage of one or more capacitor modules; selecting one of a plurality of charging modes to charge one or more capacitor modules according to the voltage of the capacitor modules; detecting the frequency of the power grid; performing constant frequency on the power grid; wherein the step of performing constant frequency on the power grid comprises the steps of performing step-down rectification on alternating current of the power grid into direct current according to the frequency of the power grid and transmitting the direct current to the capacitor module for charging, or performing inversion and step-up on the direct current of the capacitor module into alternating current and transmitting the alternating current to the power grid for power supply; furthermore, the charging mode limits the charging voltage or the charging current of the capacitor module; therefore, different charging modes are used for charging and energy storage of the capacitor module for frequency modulation of a power grid, the defect that the capacitor module cannot be directly charged and recovered through existing equipment when the capacitor module is not used for a long time and the voltage is reduced is overcome, and the user experience is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of power grid frequency modulation, and in particular relates to a power grid frequency modulation method and system based on a supercapacitor. Background Art

[0002] With the development and progress of science and technology, the research and development of new energy sources is imperative. At present, lithium-ion battery energy storage accounts for more than 90% of the installed capacity of new energy storage devices. In energy-type frequency modulation energy storage applications, frequent high-rate shallow charging and discharging of lithium batteries will reduce the service life of lithium batteries. Therefore, supercapacitor energy storage is needed to make up for this deficiency of lithium battery energy storage.

[0003] Supercapacitors are power-type energy storage devices with the advantages of high power density, fast response speed, long cycle life, good safety performance, and a wide operating temperature range. They are effective in smoothing instantaneous power fluctuations. However, the current low-voltage range of supercapacitor energy storage systems is relatively low, resulting in a relatively wide voltage range requirement for charging and discharging equipment, and the cost of large supercapacitor energy storage systems remains high. Summary of the invention

[0004] In view of the above-mentioned deficiencies in the prior art, the purpose of the present invention is to provide a grid frequency regulation method and system based on supercapacitors, aiming to solve the problem that the prior art cannot provide an effective grid frequency regulation method based on supercapacitors, resulting in the inability to perform energy storage frequency regulation when the voltage of the supercapacitor is too low, resulting in poor user experience.

[0005] In one aspect, the present invention provides a method for power grid frequency regulation based on a supercapacitor, the method comprising the following steps:

[0006] Detecting the voltage of one or more capacitor modules;

[0007] Selecting one of a plurality of charging modes according to the voltage of the capacitor module to charge one or more of the capacitor modules; the charging mode limits the charging voltage or charging current of the capacitor module;

[0008] detecting a frequency of the power grid;

[0009] Maintaining a constant frequency on the power grid;

[0010] Maintaining a constant frequency on the power grid includes: stepping down and rectifying the AC power of the power grid into DC power according to the frequency of the power grid and transmitting it to the capacitor module for charging, or inverting and stepping up the DC power of the capacitor module into AC power and transmitting it to the power grid for power supply.

[0011] Preferably, the plurality of charging modes include at least: a first charging mode, a second charging mode and a third charging mode;

[0012] When the voltage of the capacitor module is within the first voltage range, the capacitor module is charged using the first charging mode; when the voltage of the capacitor module is within the second voltage range, the capacitor module is charged using the second charging mode; when the voltage of the capacitor module is within the third voltage range, the capacitor module is charged using the third charging mode;

[0013] The charging voltage of the first charging mode is lower than the charging voltage of the second charging mode, and the charging voltage of the second charging mode is lower than the charging voltage of the third charging mode.

[0014] Furthermore, the first charging mode, the second charging mode and the third charging mode all perform constant current charging on the capacitor module.

[0015] Furthermore, the method further includes: disconnecting corresponding multiple capacitor modules to supply power to the power grid according to the voltages of the multiple capacitor modules.

[0016] In another aspect, the present invention provides a supercapacitor-based grid frequency modulation system, the system comprising:

[0017] One or more capacitor modules, composed of multiple supercapacitors;

[0018] One or more voltage detection units, detecting the voltage of one or more capacitor modules;

[0019] One or more charging units, selecting one of a plurality of charging modes according to the voltage of the capacitor module to charge the one or more capacitor modules; the charging mode limits the charging voltage or charging current of the capacitor module;

[0020] A frequency detection unit, detecting the frequency of the power grid;

[0021] An energy storage converter, which operates the power grid at a constant frequency and is controlled by a frequency modulation unit;

[0022] The frequency modulation unit controls the working state of the energy storage converter according to the frequency of the power grid to adjust the frequency of the power grid to a constant frequency;

[0023] The working states of the energy storage converter include: charging state and inversion state; the charging state includes: stepping down and rectifying the AC power of the power grid into DC power and transmitting it to the capacitor module for charging; the inversion state includes: inverting and stepping up the DC power of the capacitor module into AC power and transmitting it to the power grid for power supply.

[0024] The system of the present invention, wherein the plurality of charging modes at least include: a first charging mode, a second charging mode and a third charging mode;

[0025] When the voltage of the capacitor module is within the first voltage range, the capacitor module is charged using the first charging mode; when the voltage of the capacitor module is within the second voltage range, the capacitor module is charged using the second charging mode; when the voltage of the capacitor module is within the third voltage range, the capacitor module is charged using the third charging mode;

[0026] The charging voltage of the first charging mode is lower than the charging voltage of the second charging mode, and the charging voltage of the second charging mode is lower than the charging voltage of the third charging mode.

[0027] The system of the present invention, wherein the charging unit further comprises: a first charging unit, a second charging unit and a third charging unit;

[0028] The first charging unit includes: a charging resistor connected in series between the energy storage converter and the capacitor module; the second charging unit includes: a charging module connected to the capacitor module to charge the capacitor module; the third charging unit includes: a normally open contact of a first contactor connected in series between the energy storage converter and the capacitor module;

[0029] The charging module draws power from any one of the power grid, the energy storage converter, and the three-phase AC mains;

[0030] The first charging mode uses the first charging unit to charge the capacitor module, the second charging mode uses the second charging unit to charge the capacitor module, and the third charging mode uses the third charging unit to charge the capacitor module.

[0031] The system of the present invention, wherein the system further comprises:

[0032] One or more power-off units disconnect corresponding capacitor modules from supplying power to the power grid according to the voltage of the capacitor modules.

[0033] The system of the present invention, wherein the third charging unit is further used to disconnect one or more of the capacitor modules from supplying power to the power grid;

[0034] The system further comprises: a surge protector connected to the energy storage converter and grounded.

[0035] On the other hand, the present invention also provides a computer program product, which includes a computer program stored on a non-volatile computer-readable storage medium, and the computer program includes program instructions. When the program instructions are executed by a processor, the processor executes the above-mentioned supercapacitor-based grid frequency modulation method.

[0036] The beneficial effects of the present invention are: detecting the voltage of one or more capacitor modules; selecting one of a plurality of charging modes to charge one or more capacitor modules according to the voltage of the capacitor module; detecting the frequency of the power grid; maintaining a constant frequency of the power grid; wherein maintaining a constant frequency of the power grid includes: according to the frequency of the power grid, reducing the voltage of the AC power of the power grid and rectifying it into DC power and transmitting it to the capacitor module for charging, or inverting and boosting the DC power of the capacitor module into AC power and transmitting it to the power grid for power supply, for example: when the frequency of the power grid is low, the DC power of the capacitor module is inverted and boosted into AC power and transmitted to the power grid for power supply, and conversely, when the frequency of the power grid is high, the AC power of the power grid is reduced and rectified into DC power and transmitted to the capacitor module for charging; further, the charging mode limits the charging voltage or charging current of the capacitor module; thereby realizing the use of different charging modes to charge and store energy for the capacitor module for use in frequency modulation of the power grid, making up for the deficiency that when the capacitor module is not used for a long time, the voltage is reduced and it cannot be directly charged and restored by existing equipment, thereby improving the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 is a flow chart of an implementation method of a supercapacitor-based power grid frequency modulation method provided in Embodiment 1 of the present invention;

[0038] Figure 2 is a structural schematic diagram of a supercapacitor-based power grid frequency modulation system provided in Embodiment 2 of the present invention;

[0039] Figure 3 It is a structural schematic diagram of a first charging unit, a second charging unit and a third charging unit of a supercapacitor-based power grid frequency modulation system provided in Embodiment 2 of the present invention;

[0040] Figure 4 is a circuit block diagram of a supercapacitor-based power grid frequency modulation circuit provided in Embodiment 3 of the present invention;

[0041] Figure 5 It is a circuit schematic diagram of a first charging unit and a third charging unit of a supercapacitor-based grid frequency modulation circuit provided in Embodiment 3 of the present invention;

[0042] Figure 6 It is a circuit schematic diagram of the second charging module of the supercapacitor-based grid frequency modulation circuit provided in the third embodiment of the present invention. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0044] The specific implementation of the present invention is described in detail below in conjunction with specific embodiments:

[0045] Embodiment 1:

[0046] Figure 1 The implementation process of the supercapacitor-based grid frequency modulation method provided in the first embodiment of the present invention is shown. For the convenience of explanation, only the part related to the embodiment of the present invention is shown, which is described in detail as follows:

[0047] In step S101, the voltage of one or more capacitor modules is detected;

[0048] In an embodiment of the present invention, the voltage of the capacitor module is detected to intelligently charge the capacitor module, for example, different charging modes are selected for charging according to the voltage of the capacitor module.

[0049] In step S102, one of a plurality of charging modes is selected according to the voltage of the capacitor module to charge one or more capacitor modules;

[0050] In an embodiment of the present invention, the charging mode limits the charging voltage or the charging current of the capacitor module;

[0051] Preferably, the multiple charging modes include at least: a first charging mode, a second charging mode and a third charging mode;

[0052] When the voltage of the capacitor module is within the first voltage range, the capacitor module is charged using the first charging mode; when the voltage of the capacitor module is within the second voltage range, the capacitor module is charged using the second charging mode; when the voltage of the capacitor module is within the third voltage range, the capacitor module is charged using the third charging mode;

[0053] Among them, the charging voltage of the first charging mode is lower than the charging voltage of the second charging mode, and the charging voltage of the second charging mode is lower than the charging voltage of the third charging mode; the three voltages are used to charge the capacitor module to fully charge the capacitor module from 0V to a normal working voltage, thereby compensating for the deficiency that the capacitor module voltage is too low and the energy storage inverter cannot charge it.

[0054] Furthermore, the first charging mode, the second charging mode and the third charging mode all perform constant current charging on the capacitor module to protect the capacitor module.

[0055] In step S103, the frequency of the power grid is detected;

[0056] In an embodiment of the present invention, the frequency of the power grid is detected so that the AC power of the power grid can be stepped down and rectified into DC power in real time according to the frequency of the power grid and transmitted to the capacitor module for charging, or the DC power of the capacitor module can be inverted and stepped up into AC power and transmitted to the power grid for power supply, thereby achieving a constant frequency of the power grid.

[0057] In step S104, the power grid is subjected to constant frequency;

[0058] In an embodiment of the present invention, maintaining a constant frequency of the power grid includes: stepping down and rectifying the AC power of the power grid into DC power according to the frequency of the power grid and transmitting it to the capacitor module for charging, or inverting and boosting the DC power of the capacitor module into AC power and transmitting it to the power grid for power supply.

[0059] Furthermore, the method also includes: disconnecting the corresponding multiple capacitor modules from supplying power to the power grid according to the voltages of the multiple capacitor modules; for example: when the voltage of the capacitor module is too low, disconnecting the power supply to the power grid, and preferentially using other capacitor modules with higher voltages to supply power to the power grid, so as to avoid running out of power in the capacitor module and requiring a longer time to charge and restore it.

[0060] In an embodiment of the present invention, the voltage of one or more capacitor modules is detected; one of a plurality of charging modes is selected to charge the one or more capacitor modules according to the voltage of the capacitor module; the frequency of the power grid is detected; and the power grid is kept at a constant frequency; wherein, keeping the power grid at a constant frequency includes: according to the frequency of the power grid, the alternating current of the power grid is stepped down and rectified into direct current and transmitted to the capacitor module for charging, or the direct current of the capacitor module is inverted and stepped up into alternating current and transmitted to the power grid for power supply, for example: when the frequency of the power grid is low, the direct current of the capacitor module is inverted and stepped up into alternating current and transmitted to the power grid for power supply, and vice versa, when the frequency of the power grid is high, the alternating current of the power grid is stepped down and rectified into direct current and transmitted to the capacitor module for charging, so as to realize constant frequency and make up for the deficiency of low or high frequency of the power grid caused by insufficient or excessive power generation of the power plant; further, the charging mode limits the charging voltage or charging current of the capacitor module; thereby realizing the use of different charging modes to charge and store energy for the capacitor module for use in frequency modulation of the power grid, making up for the deficiency that the voltage of the capacitor module is reduced when it is not used for a long time and it cannot be directly charged and restored by existing equipment, thereby improving the user experience.

[0061] Embodiment 2:

[0062] Figure 2 and Figure 3 The structure of the supercapacitor-based grid frequency modulation system provided by the second embodiment of the present invention is shown. For the convenience of description, only the parts related to the embodiment of the present invention are shown, including:

[0063] One or more capacitor modules 210 are composed of multiple supercapacitors; wherein the capacitor module 210 is composed of multiple supercapacitors connected in series, in parallel, or in series and parallel;

[0064] One or more voltage detection units 220, detecting the voltage of one or more capacitor modules 210;

[0065] One or more charging units 230, selecting one of a plurality of charging modes to charge one or more capacitor modules 210 according to the voltage of the capacitor module 210; the charging mode limits the charging voltage or charging current of the capacitor module 210;

[0066] The frequency detection unit 240 detects the frequency of the power grid 200; wherein the power grid is an AC power grid and the voltage is 35KV or 690V;

[0067] The energy storage converter 250 maintains a constant frequency for the power grid 200 and is controlled by the frequency modulation unit 260 . Furthermore, the energy storage converter 250 maintains a constant frequency for the power grid 200 by switching between a charging state and an inversion state.

[0068] The frequency modulation unit 260 controls the working state of the energy storage converter 250 according to the frequency of the power grid 200 to adjust the frequency of the power grid 200 to a constant frequency; for example, when the frequency of the power grid 200 is low, the energy storage converter 250 is controlled to use the inverter mode, otherwise it is controlled to use the charging mode.

[0069] The working states of the energy storage inverter 250 include: charging state and inversion state; the charging state includes: stepping down and rectifying the AC power of the power grid 200 into DC power and transmitting it to the capacitor module 210 for charging; the inversion state includes: inverting and boosting the DC power of the capacitor module 210 into AC power and transmitting it to the power grid 200 for power supply.

[0070] Preferably, the multiple charging modes include at least: a first charging mode, a second charging mode and a third charging mode;

[0071] When the voltage of the capacitor module 210 is within the first voltage range, the capacitor module 210 is charged using the first charging mode; when the voltage of the capacitor module 210 is within the second voltage range, the capacitor module 210 is charged using the second charging mode; when the voltage of the capacitor module 210 is within the third voltage range, the capacitor module 210 is charged using the third charging mode;

[0072] The charging voltage of the first charging mode is lower than the charging voltage of the second charging mode, and the charging voltage of the second charging mode is lower than the charging voltage of the third charging mode.

[0073] Furthermore, the charging unit 230 further includes: a first charging unit 231, a second charging unit 232 and a third charging unit 233;

[0074] The first charging unit 231 includes: a charging resistor connected in series between the energy storage converter 250 and the capacitor module 210 to achieve current limiting and voltage division, and the cost is low, and the charging resistor preferably uses a 200R / 200W charging resistor; the second charging unit 232 includes: a charging module (not shown in the figure) connected to the capacitor module 210 to charge the capacitor module 210, which is more efficient than using a series charging resistor to charge the capacitor module 210; the third charging unit 233 includes: a charging module connected in series with the energy storage converter 250 and the capacitor module 210 to charge the capacitor module 210; The normally open contact of the first contactor between 250 and the capacitor module 210, that is, directly charging the capacitor module 210 through the energy storage inverter 250, is more efficient than using the charging module to charge the capacitor module 210; for example: using a series charging resistor is suitable for use when the voltage of the capacitor module 210 is 0V-150V, using the charging module when the voltage of the capacitor module 210 is 150V-1000V, and using the energy storage inverter 250 when the voltage of the capacitor module 210 is higher than 1000V.

[0075] The charging module takes power from any one of the power grid 200, the energy storage converter 250, and the three-phase AC mains to meet the working requirements of different charging modules;

[0076] The first charging mode uses the first charging unit 231 to charge the capacitor module 210 , the second charging mode uses the second charging unit 232 to charge the capacitor module 210 , and the third charging mode uses the third charging unit 233 to charge the capacitor module 210 .

[0077] Furthermore, the system also includes:

[0078] One or more power-off units 270 disconnect corresponding capacitor modules 210 from supplying power to the power grid 200 according to the voltage of the capacitor modules 210, thereby realizing secondary disconnection protection of the power grid 200 on the capacitor modules and improving stability.

[0079] Preferably, the third charging unit 233 is also used to disconnect one or more capacitor modules 210 from supplying power to the grid 200; to realize a primary disconnection function of the grid 200 on the capacitor module, and the current flows bidirectionally in the third charging unit 233;

[0080] The system also includes: a surge protector 280, which is connected to the energy storage converter 250 and grounded; it performs lightning protection to improve stability and safety.

[0081] In an embodiment of the present invention, each unit of the supercapacitor-based grid frequency modulation system can be implemented by a corresponding hardware or software unit. Each unit can be an independent software or hardware unit or integrated into one software or hardware unit, which is not intended to limit the present invention.

[0082] Embodiment three:

[0083] The grid frequency modulation circuit based on supercapacitor in the preferred embodiment of the present invention is as follows Figure 4 See also Figure 5 and Figure 6 ; including multiple capacitor modules 310 and one or more charging units 330 and an energy storage converter 350; wherein the energy storage converter 350 is connected in series between the power grid 300 and one or more charging units 330, and multiple capacitor modules 310 are connected in series with the charging units 330;

[0084] The plurality of capacitor modules 310 are also connected to a voltage detection unit 320 , and the voltage detection unit 320 is connected to a charging unit 330 ;

[0085] The power grid 300 is connected to a frequency detection unit 340, the frequency detection unit 340 is connected to a frequency modulation unit 360, and the frequency modulation unit 360 is connected to an energy storage converter 350;

[0086] The capacitor module 310 is composed of a plurality of supercapacitors (not shown in the figure);

[0087] A voltage detection unit 320 detects the voltage of the plurality of capacitor modules 310;

[0088] The charging unit 330 selects one of the first charging mode, the second charging mode, and the third charging mode to charge the capacitor module 310 according to the voltage of the capacitor module 310;

[0089] A frequency detection unit 340, for detecting the frequency of the power grid 300;

[0090] The energy storage converter 350 maintains a constant frequency for the power grid 300 and is controlled by the frequency modulation unit 360 . Furthermore, the energy storage converter 350 maintains a constant frequency for the power grid 300 by switching between a charging state and an inversion state.

[0091] The frequency modulation unit 360 controls the working state of the energy storage converter 350 according to the frequency of the power grid 300 to adjust the frequency of the power grid 300 to a constant frequency; for example, when the frequency of the power grid 300 is low, the energy storage converter 350 is controlled to use the inverter mode, otherwise it uses the charging mode.

[0092] The working states of the energy storage inverter 350 include: charging state and inversion state; the charging state includes: stepping down and rectifying the AC power of the power grid 300 into DC power and transmitting it to the capacitor module 310 for charging; the inversion state includes: inverting and boosting the DC power of the capacitor module 310 into AC power and transmitting it to the power grid 300 for power supply.

[0093] The capacitor module 310 is composed of multiple supercapacitors to increase the capacitance and voltage; the voltage detection unit 320 detects the voltage of multiple capacitor modules 310; the charging unit 330 selects one of the first charging mode, the second charging mode, and the third charging mode to charge the capacitor module 310 according to the voltage of the capacitor module 310; the frequency detection unit 340 detects the frequency of the power grid 300; the energy storage converter 350 controls the power grid 300 to maintain a constant frequency and is controlled by the frequency modulation unit 360; the frequency modulation unit 360 controls the working state of the energy storage converter 350 according to the frequency of the power grid 300 to adjust the frequency of the power grid 300 to maintain a constant frequency;

[0094] The working states of the energy storage converter 350 include: a charging state and an inversion state; the charging state includes: stepping down and rectifying the AC power of the power grid 300 into DC power and transmitting it to the capacitor module 310 for charging; the inversion state includes: inverting and boosting the DC power of the capacitor module 310 into AC power and transmitting it to the power grid 300 for power supply; further, the energy storage converter 350 performs constant frequency on the power grid 300 by switching the charging state or the inversion state;

[0095] For example, when the frequency of the power grid 300 is low, the DC power of the capacitor module 310 is inverted and boosted into AC power and transmitted to the power grid 300 for power supply. On the contrary, when the frequency of the power grid 300 is high, the AC power of the power grid 300 is stepped down and rectified into DC power and transmitted to the capacitor module 310 for charging, so as to achieve constant frequency and make up for the low or high frequency of the power grid 300 caused by insufficient or excessive power generation of the power plant.

[0096] This makes it possible to use different charging modes to charge and store energy in the capacitor module 310 for use in frequency modulation of the power grid 300, making up for the deficiency that when the capacitor module 310 is not used for a long time and the voltage drops, it cannot be directly charged and restored by existing equipment. It is low-cost and small in size, thereby improving user experience.

[0097] like Figure 4 As shown, it also includes: a power-off unit 370 connected in series between the energy storage converter 350 and the charging unit 330;

[0098] The power-off unit 370 disconnects the corresponding multiple capacitor modules 310 from supplying power to the power grid 300 according to the voltage of the multiple capacitor modules 310. The power-off unit 370 is connected to the voltage detection unit 320 connected to the corresponding multiple capacitor modules 310; and the electrical connection between the capacitor modules 310 and the power grid 300 is disconnected in batches.

[0099] Furthermore, it also includes: a surge protector 380, which is connected to the energy storage converter 350 and grounded to provide lightning protection and improve stability and safety.

[0100] like Figures 4 to 6As shown, the charging unit 330 further includes: a first charging unit 331, a second charging unit 332 and a third charging unit 333;

[0101] The first charging unit 331 includes: a charging resistor R1 connected in series between the energy storage inverter 350 and the capacitor module 310, the second charging unit 332 includes: a charging module U1 connected to the capacitor module 310 to charge the capacitor module 310, and the third charging unit 333 includes: a normally open contact of the first contactor KM1 connected in series between the energy storage inverter 350 and the capacitor module 310; for example: using a series charging resistor is suitable for use when the voltage of the capacitor module 310 is 0V-150V, using the charging module U1 when the voltage of the capacitor module 310 is 150V-1000V, and using the energy storage inverter 350 when the voltage of the capacitor module 310 is higher than 1000V; wherein, the charging module U1 is a rectifier and step-down module.

[0102] The first charging mode uses the first charging unit 331 to charge the capacitor module 310, the second charging mode uses the second charging unit 332 to charge the capacitor module 310, and the third charging mode uses the third charging unit 333 to charge the capacitor module 310; the circuit is simple, low cost, small size, and low power loss.

[0103] Preferably, the charging module U1 draws power from any one of the power grid 300 , the energy storage converter 350 , and the three-phase AC mains to meet different usage requirements.

[0104] like Figure 4 As shown, the power-off unit 370 also includes: a plurality of normally open contacts of a second contactor (not shown in the figure); using the plurality of normally open contacts of the contactor to perform switch power off has a simple circuit, is easy to control, and has high safety.

[0105] like Figure 4 As shown, it also includes: a capacitor stack 400;

[0106] The capacitor stack 400 includes: a power-off unit 370, a charging unit 330, a capacitor cluster 410 and a voltage detection unit 320;

[0107] The capacitor cluster 410 includes: a plurality of capacitor modules 310 connected in series; the capacitor modules 310 are combined into an energy storage cabinet for modular use, which is convenient for expansion, installation and maintenance.

[0108] like Figure 4 and Figure 6 As shown, the second charging unit 332 includes: a charging module U1 and a third contactor KM3;

[0109] The coil of the first contactor KM1 is interlocked with the coil of the third contactor KM3 to prevent the high voltage charged by the energy storage converter 350 to the capacitor cluster 410 from being reversely input to the charging module U1, thereby damaging the charging module U1.

[0110] The multiple normally open contacts of the third contactor KM3 control the power input of the charging module U1, which is highly safe.

[0111] like Figure 4 and Figure 5 As shown, the first charging unit 331 further includes: a fourth contactor KM4;

[0112] The normally open contact of the fourth contactor KM4 is connected in series with the charging resistor R1 and then connected in series between the energy storage converter 350 and the capacitor module 310 to implement charging control using the charging resistor R1.

[0113] Further preferably, the first charging mode, the second charging mode and the third charging mode all perform constant voltage and constant current charging on the capacitor module 310 to meet different usage requirements.

[0114] Preferably, the charging unit 330 also selects one of a plurality of charging modes to charge a plurality of capacitor modules 310 according to the voltage of the capacitor module 310, so as to adapt to different charging requirements;

[0115] The plurality of charging modes include at least a first charging mode, a second charging mode and a third charging mode.

[0116] Embodiment 4:

[0117] Embodiment 4 of the present invention provides a computer program product, the computer program product includes a computer program stored in a non-volatile computer-readable storage medium, the computer program includes program instructions, when the program instructions are executed by a processor, the processor executes the supercapacitor-based grid frequency modulation method of the above method embodiment. For example, executing the above described Figure 1 The method comprises steps S101 to S104.

[0118] The embodiments described above are merely illustrative, in which the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0119] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a general hardware platform, and of course can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the relevant technology can be embodied in the form of a software product, and the computer software product can exist in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer electronic device (which can be a personal computer, a server, or a network electronic device, etc.) to execute the methods of each embodiment or some parts of the embodiment.

[0120] Conditional language such as "can," "can," "might," or "may," among other things, unless specifically stated otherwise or otherwise understood within the context as used, is generally intended to convey that particular embodiments can include (while other embodiments do not) particular features, elements, and / or operations. Thus, such conditional language is generally not intended to imply that features, elements, and / or operations are in any way required for one or more embodiments or that one or more embodiments must include logic for determining whether such features, elements, and / or operations are included or will be performed in any particular embodiment, with or without student input or prompting.

[0121] What has been described herein in this specification and the accompanying drawings includes examples of methods and systems for grid frequency regulation based on supercapacitors. Of course, it is not possible to describe every conceivable combination of elements and / or methods for the purpose of describing the various features of the present disclosure, but it is recognized that many other combinations and permutations of the disclosed features are possible. Therefore, it is apparent that various modifications can be made to the present disclosure without departing from the scope or spirit of the present disclosure. In addition, or in an alternative, other embodiments of the present disclosure may be apparent from consideration of the present specification and the accompanying drawings and from the practice of the present disclosure as presented herein. It is intended that the examples set forth in the present specification and the accompanying drawings are considered to be illustrative and not restrictive in all respects. Although specific terms are employed herein, they are used in a general and descriptive sense and are not used for limiting purposes.

Claims

1. A method for power grid frequency modulation based on supercapacitors, characterized in that: The method comprises the following steps: Detecting the voltage of one or more capacitor modules; Selecting one of a plurality of charging modes according to the voltage of the capacitor module to charge one or more of the capacitor modules; the charging mode limits the charging voltage or charging current of the capacitor module; detecting a frequency of the power grid; Maintaining a constant frequency on the power grid; Maintaining a constant frequency on the power grid includes: stepping down and rectifying the AC power of the power grid into DC power according to the frequency of the power grid and transmitting it to the capacitor module for charging, or inverting and stepping up the DC power of the capacitor module into AC power and transmitting it to the power grid for power supply.

2. The method according to claim 1, characterized in that The plurality of charging modes at least include: a first charging mode, a second charging mode and a third charging mode; When the voltage of the capacitor module is within the first voltage range, the capacitor module is charged using the first charging mode; when the voltage of the capacitor module is within the second voltage range, the capacitor module is charged using the second charging mode; when the voltage of the capacitor module is within the third voltage range, the capacitor module is charged using the third charging mode; The charging voltage of the first charging mode is lower than the charging voltage of the second charging mode, and the charging voltage of the second charging mode is lower than the charging voltage of the third charging mode.

3. The method according to claim 2, characterized in that The first charging mode, the second charging mode, and the third charging mode all perform constant current charging on the capacitor module.

4. The method according to claim 1, characterized in that The method further includes: disconnecting corresponding multiple capacitor modules according to the voltages of the multiple capacitor modules to supply power to the power grid.

5. A supercapacitor-based power grid frequency modulation system, characterized in that: The system comprises: One or more capacitor modules, composed of multiple supercapacitors; One or more voltage detection units, detecting the voltage of one or more capacitor modules; One or more charging units, selecting one of a plurality of charging modes according to the voltage of the capacitor module to charge the one or more capacitor modules; the charging mode limits the charging voltage or charging current of the capacitor module; A frequency detection unit, detecting the frequency of the power grid; An energy storage converter, which operates the power grid at a constant frequency and is controlled by a frequency modulation unit; The frequency modulation unit controls the working state of the energy storage converter according to the frequency of the power grid to adjust the frequency of the power grid to a constant frequency; The working states of the energy storage converter include: charging state and inversion state; the charging state includes: stepping down and rectifying the AC power of the power grid into DC power and transmitting it to the capacitor module for charging; the inversion state includes: inverting and stepping up the DC power of the capacitor module into AC power and transmitting it to the power grid for power supply.

6. The system according to claim 5, characterized in that The plurality of charging modes at least include: a first charging mode, a second charging mode and a third charging mode; When the voltage of the capacitor module is within the first voltage range, the capacitor module is charged using the first charging mode; when the voltage of the capacitor module is within the second voltage range, the capacitor module is charged using the second charging mode; when the voltage of the capacitor module is within the third voltage range, the capacitor module is charged using the third charging mode; The charging voltage of the first charging mode is lower than the charging voltage of the second charging mode, and the charging voltage of the second charging mode is lower than the charging voltage of the third charging mode.

7. The system according to claim 6, characterized in that The charging unit further includes: a first charging unit, a second charging unit and a third charging unit; The first charging unit includes: a charging resistor connected in series between the energy storage converter and the capacitor module; the second charging unit includes: a charging module connected to the capacitor module to charge the capacitor module; the third charging unit includes: a normally open contact of a first contactor connected in series between the energy storage converter and the capacitor module; The charging module draws power from any one of the power grid, the energy storage converter, and the three-phase AC mains; The first charging mode uses the first charging unit to charge the capacitor module, the second charging mode uses the second charging unit to charge the capacitor module, and the third charging mode uses the third charging unit to charge the capacitor module.

8. The system according to claim 5, characterized in that The system further comprises: One or more power-off units disconnect corresponding capacitor modules from supplying power to the power grid according to the voltage of the capacitor modules.

9. The system according to claim 7, characterized in that The third charging unit is further used to disconnect one or more capacitor modules from supplying power to the power grid; The system further comprises: a surge protector connected to the energy storage converter and grounded.

10. A computer program product, characterized in that The computer program product comprises a computer program stored on a non-volatile computer-readable storage medium, wherein the computer program comprises program instructions, and when the program instructions are executed by a processor, the processor is caused to execute the supercapacitor-based grid frequency modulation method according to any one of claims 1 to 4.

Images