Hybrid inverter and off-grid switching device and switching switch device

Abstract

The application relates to a hybrid inverter parallel-off-grid switching device and a switching switch device, the switching switch device comprising a relay, a shutdown module, a first starting module, a second starting module, a switching control module and a control module, the relay being connected with the shutdown module, the first starting module, the second starting module and the switching control module respectively, and the switching control module being further connected with the control module and the second starting module respectively. The switching switch device is applied to the hybrid inverter parallel-off-grid switching device, the relay can be quickly shut down through the shutdown module of the switching switch device, the disconnection speed of the hybrid inverter when quickly switching to the energy storage power supply mode during power grid failure is improved, power grid loss is reduced, and the problems of slow disconnection speed and large loss of the existing hybrid inverter when quickly switching to the energy storage power supply mode during power grid failure are solved.

Description

Technical Field

[0001] This application belongs to the field of inverter technology, and in particular relates to a hybrid inverter on-grid and off-grid switching device and a switching device. Background Technology

[0002] With the increasing use of non-renewable resources and the large-scale integration of new energy sources (such as intermittent power sources like solar and wind power) into the grid, the use of non-renewable resources is decreasing. This integration of existing new energy sources into the grid poses challenges to the stability of the traditional power grid. Current solutions employ hybrid inverters to coordinate distributed energy sources (such as solar power), energy storage batteries, and the grid to balance supply and demand fluctuations. However, the volatility of renewable energy necessitates the smoothing effect of energy storage systems, and hybrid inverters must quickly switch to energy storage power supply mode during grid failures to ensure continuous energy supply.

[0003] Existing hybrid inverters use either thyristors or relays to quickly switch to energy storage power supply mode during grid faults. Thyristor switching relies on zero-crossing current turn-off, resulting in switching times exceeding 20ms, complex control, and the need for additional heat dissipation for semiconductor devices. Relay switching directly supplies the coil with the rated voltage, resulting in slow disconnection and high coil losses. Utility Model Content

[0004] One embodiment of this application provides a hybrid inverter on-grid switching device and a switching device to solve the problems of slow disconnection speed and high loss in existing hybrid inverters when quickly switching to energy storage power supply mode during grid faults.

[0005] In a first aspect, one embodiment of this application provides a switching device, comprising:

[0006] A relay, including a coil;

[0007] A shutdown module is connected in parallel with the coil. The shutdown module includes a fourth semiconductor element, an energy storage element, and a third resistor. The anode of the fourth semiconductor element is connected to the second end of the coil. The cathode of the fourth semiconductor element is connected to the second end of the energy storage element and the second end of the third resistor, respectively. The first end of the energy storage element and the first end of the third resistor are both connected to the first end of the coil.

[0008] A first start-up module is connected to a first terminal of the shut-off module and a first terminal of the coil. The first start-up module is used to provide a first voltage to the coil and the energy storage element.

[0009] The second start module is connected to the first end of the shut-off module and the first end of the coil. The second start module is used to provide a second voltage to the coil and the energy storage element.

[0010] A switching control module is connected to the second starting module and the second end of the coil. The switching control module is used to control whether the second starting module provides a second voltage to the coil and / or the energy storage element.

[0011] A control module is connected to the switching control module, and the control module is used to provide switching signals and control signals to the switching control module.

[0012] Optionally, the switching control module includes a first switching transistor and a third switching transistor. The first end of the first switching transistor and the first end of the third switching transistor are both connected to the control module. The second ends of the first switching transistor and the second ends of the third switching transistor are both grounded. The third end of the first switching transistor is connected to the anode of the fourth semiconductor element and the second end of the coil, respectively. The third end of the third switching transistor is connected to the second starting module.

[0013] Optionally, the second startup module includes a second switching transistor and a first semiconductor element. The first end of the second switching transistor is connected to the third end of the third switching transistor through a second resistor. The second end of the second switching transistor is connected to a DC power supply. The third end of the second switching transistor is connected to the anode of the first semiconductor element. The cathode of the first semiconductor element is connected to the first end of the coil.

[0014] Optionally, the first startup module includes a DC / DC converter and a second semiconductor element. The input terminal of the DC / DC converter is connected to a DC power supply, the output terminal of the DC / DC converter is connected to the anode of the second semiconductor element, and the cathode of the second semiconductor element is connected to the first end of the coil.

[0015] Optionally, the first switch, the second switch, and the third switch are all MOSFETs, with the gate of the MOSFET serving as the first terminal of the first switch, the second switch, and the third switch, the source of the MOSFET serving as the second terminal of the first switch, the second switch, and the third switch, and the drain of the MOSFET serving as the third terminal of the first switch, the second switch, and the third switch.

[0016] Optionally, both the first semiconductor element and the fourth semiconductor element are diodes, with the anode of the diode serving as the anode of both the first and fourth semiconductor elements, and the cathode of the diode serving as the cathode of both the first and fourth semiconductor elements.

[0017] Optionally, the DC power supply is also connected to the control module.

[0018] Optionally, the control module includes a microcontroller unit.

[0019] Optionally, the energy storage element is a capacitor.

[0020] Secondly, one embodiment of this application provides a hybrid inverter and off-grid switching device, including a DC / AC inverter, a first AC electromagnetic interference filter, a first switch, a second switch, a third switch, a fourth switch, a second AC electromagnetic interference filter, and a power grid. The input terminal of the DC / AC inverter is connected to a power source, the output terminal of the DC / AC inverter is connected to the input terminal of the first AC electromagnetic interference filter, the output terminal of the first AC electromagnetic interference filter is connected to the input terminal of the first switch, the output terminal of the first switch is connected to the input terminals of the second switch and the fourth switch, the output terminal of the second switch is connected to the input terminal of the third switch, the output terminal of the third switch is connected to the input terminal of the second AC electromagnetic interference filter, the output terminal of the second AC electromagnetic interference filter is connected to the power grid, and the output terminal of the fourth switch is connected to a load. The first switch, the second switch, the third switch, and the fourth switch are all switching devices as described above.

[0021] One embodiment of this application provides a hybrid inverter grid-connected switching device and a switching device. The switching device includes a relay with a coil; a shutdown module connected in parallel with the coil, the shutdown module including a fourth semiconductor element, an energy storage element, and a third resistor, the anode of the fourth semiconductor element being connected to the second end of the coil, the cathode of the fourth semiconductor element being connected to the second end of the energy storage element and the second end of the third resistor respectively, and the first end of the energy storage element and the first end of the third resistor being connected to the first end of the coil; a first start-up module connected to the first end of the shutdown module and the first end of the coil, the first start-up module being used to provide a first voltage to the coil and the energy storage element; a second start-up module connected to the first end of the shutdown module and the first end of the coil, the second start-up module being used to provide a second voltage to the coil and the energy storage element; a switching control module connected to the second start-up module and the second end of the coil, the switching control module being used to control whether the second start-up module provides the second voltage to the coil and / or the energy storage element; and a control module connected to the switching control module, the control module being used to provide a switching signal and a control signal to the switching control module. This switching device is used in the on-grid switching device of a hybrid inverter. The shutdown module of this switching device can quickly shut off the relay, improve the disconnection speed of the hybrid inverter when switching to the energy storage power supply mode during grid faults, reduce grid losses, and solve the problems of slow disconnection speed and high losses in the existing hybrid inverter when switching to the energy storage power supply mode during grid faults.

[0022] This hybrid inverter grid-connected / off-grid switching device enables seamless connection during grid-connected / off-grid switching of new energy sources by quickly disconnecting the grid via a switching device. Attached Figure Description

[0023] To more clearly illustrate the technical solution in one embodiment of this application, the accompanying drawings used in the description of the embodiment will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0024] To gain a more complete understanding of this application and its beneficial effects, the following description will be provided in conjunction with the accompanying drawings. In the following description, the same reference numerals denote the same parts.

[0025] Figure 1 A schematic diagram of the frame of a switching device provided in one embodiment of this application.

[0026] Figure 2 A circuit diagram of a switching device provided in one embodiment of this application.

[0027] Figure 3 A circuit diagram of a hybrid inverter and off-grid switching device provided in one embodiment of this application. Detailed Implementation

[0028] The technical solution of one embodiment of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0029] One embodiment of this application provides a hybrid inverter on-grid switching device and a switching device to solve the problems of slow disconnection speed and high loss in existing hybrid inverters when quickly switching to energy storage power supply mode during grid faults.

[0030] Example 1:

[0031] One embodiment of this application provides a switching device, which is exemplary; please refer to [link to example]. Figure 1 , Figure 1 A schematic diagram of the frame of a switching device provided in one embodiment of this application. Figure 2 A circuit diagram of a switching device provided in one embodiment of this application.

[0032] like Figure 1 and Figure 2As shown, this utility model application provides a switching device, including a relay 10, a shutdown module 20, a first start module 30, a second start module 40, a switching control module 50, and a control module 60.

[0033] like Figure 2 As shown in the embodiment of the present utility model, the relay 10 includes a coil, a first contact 1, and a second contact 2.

[0034] To further clarify, a disconnection module 20 is connected in parallel between the first end 4 and the second end 3 of the coil. The first end 4 of the coil is connected to the first start module 30 and the second start module 40, respectively. The second end 3 of the coil is connected to the switching control module 50.

[0035] like Figure 2 As shown in the embodiment of the present invention, the shutdown module 20 is connected in parallel with the coil. The shutdown module includes a fourth semiconductor element D4, an energy storage element C1, and a third resistor R3. The anode of the fourth semiconductor element D4 is connected to the second end 3 of the coil, and the cathode of the fourth semiconductor element D4 is connected to the second end of the energy storage element C1 and the second end of the third resistor R3, respectively. The first end of the energy storage element C1 and the first end of the third resistor R3 are both connected to the first end 4 of the coil.

[0036] Furthermore, the energy storage element C1 can be selected as a capacitor. When the relay 10 needs to be disconnected, the shutdown module 20 absorbs power through the energy storage element C1, causing the coil of the relay 10 to quickly lose power and disconnect. In this embodiment, the switching device supplies power to the coil and charges the energy storage element C1 through the first startup module 30 and the second startup module 40. The fourth semiconductor element D4 can be selected as a diode, with the anode of the diode serving as the anode and the cathode of the diode serving as the cathode.

[0037] like Figure 1 and Figure 2 As shown in the embodiment of the present invention, the first start module 30 is connected to the first end of the turn-off module 20 and the first end of the coil. The first start module 30 is used to provide a first voltage to the coil and the energy storage element C1.

[0038] To further explain, such as Figure 2 As shown, the first voltage can be 7V. In this embodiment, when the relay 10 is operating normally (e.g., its normally open contact is closed), the switching control module 50 controls the second starting module 40 to not operate, and the first starting module 30 supplies power to the coil and the energy storage element C1. When the relay 10 is not operating (e.g., its normally open contact is off / open), the switching control module 50 controls the second starting module 40 to operate, and the second starting module 40 is grounded through the energy storage element C1.

[0039] like Figure 1 and Figure 2 As shown, in an embodiment of the present invention, the second start module 40 is connected to the first end of the turn-off module 20 and the first end of the coil. The second start module 40 is used to provide a second voltage to the coil and the energy storage element C1.

[0040] Furthermore, the second voltage can be 12V. In this embodiment, when both the first starting module 30 and the second starting module 40 are working normally, the switching device can only supply power to the coil and the energy storage element C1 through the second starting module 40.

[0041] like Figure 1 and Figure 2 As shown in the embodiment of this utility model, the switching control module 50 is connected to the second starting module 40 and the second end of the coil. The switching control module 50 is used to control whether the second starting module 40 provides a second voltage to the coil and / or the energy storage element C1. The control module 60 is connected to the switching control module 50 and is used to provide switching signals and control signals to the switching control module 50.

[0042] Furthermore, the control module 60 includes a microcontroller unit (MCU), which provides switching and control signals to the switching control module 50, either at low or high levels. In this embodiment, when the normally open contact of the relay 10 is normally closed, the MCU outputs low-level switching and control signals, controlling the second startup module 40 to stop operating and cease supplying power to the energy storage element C1 and the coil. Only the first startup module 30 provides the first voltage power supply to the energy storage element C1 and the coil. When the normally open contact of the relay 10 is open or closed, the MCU outputs high-level switching and control signals, controlling the second startup module 40 to operate. The second voltage provided by the second startup module 40 is directly grounded through the energy storage element C1. A DC power supply is also connected to the control module 60.

[0043] An embodiment of this application provides a switching device including a relay with a coil; a shutdown module connected in parallel with the coil, the shutdown module including a fourth semiconductor element, an energy storage element, and a third resistor, the anode of the fourth semiconductor element being connected to the second end of the coil, the cathode of the fourth semiconductor element being connected to the second end of the energy storage element and the second end of the third resistor respectively, and the first end of the energy storage element and the first end of the third resistor being connected to the first end of the coil; a first start module connected to the first end of the shutdown module and the first end of the coil, the first start module being used to provide a first voltage to the coil and the energy storage element; a second start module connected to the first end of the shutdown module and the first end of the coil, the second start module being used to provide a second voltage to the coil and the energy storage element; a switching control module connected to the second start module and the second end of the coil, the switching control module being used to control whether the second start module provides the second voltage to the coil and / or the energy storage element; and a control module connected to the switching control module, the control module being used to provide a switching signal and a control signal to the switching control module. This switching device is used in the on-grid switching device of a hybrid inverter. The shutdown module of this switching device can quickly shut off the relay, improve the disconnection speed of the hybrid inverter when switching to the energy storage power supply mode during grid faults, reduce grid losses, and solve the problems of slow disconnection speed and high losses in the existing hybrid inverter when switching to the energy storage power supply mode during grid faults.

[0044] like Figure 2 As shown, in one embodiment of the present invention, the switching control module 50 includes a first switch Q1 and a third switch Q3. The first end of the first switch Q1 and the first end of the third switch Q3 are both connected to the control module 60. The second ends of the first switch Q1 and the third switch Q3 are both grounded. The third end of the first switch Q1 is connected to the anode of the fourth semiconductor element D4 and the second end of the coil, respectively. The third end of the third switch Q3 is connected to the second start module 40.

[0045] Furthermore, both the first switch Q1 and the third switch Q3 can be selected as MOSFETs. The gate of the MOSFET serves as the first terminal of both the first switch Q1 and the third switch Q3, the source of the MOSFET serves as the second terminal of both the first switch Q1 and the third switch Q3, and the drain of the MOSFET serves as the third terminal of both the first switch Q1 and the third switch Q3. In this embodiment, the first terminal of the third switch Q3 is connected to the control module 60 through a first resistor R1. The control module 60 provides a switching signal to the third switch Q3. The first terminal of the first switch Q1 is connected to the control module 60 through a fourth resistor R4. The control module 60 provides a control signal to the first switch Q1.

[0046] like Figure 2As shown, in one embodiment of the present invention, the second start-up module 40 includes a second switch Q2 and a first semiconductor element D1. The first end of the second switch Q2 is connected to the third end of the third switch Q3 through a second resistor R2. The second end of the second switch Q2 is connected to a DC power supply. The third end of the second switch Q2 is connected to the anode of the first semiconductor element D1. The cathode of the first semiconductor element D1 is connected to the first end of the coil.

[0047] Furthermore, the first semiconductor element D1 can be selected as a diode, with the anode of the diode serving as the anode and the cathode of the diode serving as the cathode of the first semiconductor element D1. The second switch Q2 can be selected as a MOSFET, with the gate of the MOSFET serving as the first terminal of the second switch Q2, the source of the MOSFET serving as the second terminal of the second switch Q2, and the drain of the MOSFET serving as the third terminal of the second switch Q2. In this embodiment, the working principle of the switching control module 50 is that when the switching signal and the control signal are low-level signals, the first switch Q1, the second switch Q2, and the third switch Q3 are all turned on, so that the DC power supply passes through the second switch Q2, the first semiconductor element D1, the turn-off module 20, and the first switch Q1 in sequence before being grounded. This prevents the DC power supply from supplying power to the coil through the second start-up module 40. The DC power supply is absorbed by the energy storage element C1 through the second start-up module 40, thereby achieving rapid disconnection of the circuit breaker 10.

[0048] like Figure 2 As shown, in one embodiment of the present invention, the first startup module 30 includes a DC / DC converter and a second semiconductor element D2. The input terminal of the DC / DC converter is connected to a DC power supply, the output terminal of the DC / DC converter is connected to the anode of the second semiconductor element D2, and the cathode of the second semiconductor element D2 is connected to the first end of the coil.

[0049] Furthermore, the second semiconductor element D2 can be selected as a diode, with the anode of the diode serving as the anode of the first semiconductor element and the cathode of the diode serving as the cathode of the second semiconductor element D2. The DC / DC converter is used to convert the DC power supply into a first voltage. In this embodiment, the DC power supply can be selected as 12V.

[0050] Example 2:

[0051] One embodiment of this application provides a hybrid inverter and off-grid switching device, exemplified by which please refer to [reference needed]. Figure 3 , Figure 3 A circuit diagram of a hybrid inverter and off-grid switching device provided in one embodiment of this application.

[0052] like Figure 3As shown, this utility model application provides a hybrid inverter and off-grid switching device, including a DC / AC inverter 1, a first AC electromagnetic interference filter 2, a first switch 3, a second switch 4, a third switch 5, a fourth switch 6, a second AC electromagnetic interference filter 7, and a power grid 8. The input terminal of the DC / AC inverter 1 is connected to the power supply, the output terminal of the DC / AC inverter 1 is connected to the input terminal of the first AC electromagnetic interference filter 2, the output terminal of the first AC electromagnetic interference filter 2 is connected to the input terminal of the first switch 3, the output terminal of the first switch 3 is connected to the input terminals of the second switch 4 and the fourth switch 6, the output terminal of the second switch 4 is connected to the input terminal of the third switch 5, the output terminal of the third switch 5 is connected to the input terminal of the second AC electromagnetic interference filter 7, the output terminal of the second AC electromagnetic interference filter 7 is connected to the power grid 8, and the output terminal of the fourth switch 6 is connected to the load 9. The first switch 3, the second switch 4, the third switch 5, and the fourth switch 6 are all the aforementioned switching devices.

[0053] It should be noted that the details of the switching device in this embodiment have already been described in Embodiment 1, and will not be repeated here. The power supply can be DC. In this embodiment, when the grid voltage is normal, the second switch 4, the third switch 5, and the fourth switch 6 are controlled to operate (e.g., the normally open contact of the relay in the switching device is closed); when the grid voltage is abnormal, as long as the grid-side switch is disconnected to switch to off-grid mode, the first switch 3 and the fourth switch 6 are controlled to operate (e.g., the normally open contact of the relay in the switching device is closed), and the second switch 4 and the third switch 5 are disconnected (e.g., the normally open contact of the relay in the switching device is open). This hybrid inverter grid-connected / off-grid switching device achieves seamless connection during the grid-connected / off-grid switching of new energy sources by quickly disconnecting the switching device.

[0054] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0055] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more features.

[0056] The switching device provided in one embodiment of this application has been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A switching device, characterized in that, include: A relay, including a coil; A shutdown module is connected in parallel with the coil. The shutdown module includes a fourth semiconductor element, an energy storage element, and a third resistor. The anode of the fourth semiconductor element is connected to the second end of the coil. The cathode of the fourth semiconductor element is connected to the second end of the energy storage element and the second end of the third resistor, respectively. The first end of the energy storage element and the first end of the third resistor are both connected to the first end of the coil. A first start-up module is connected to a first terminal of the shut-off module and a first terminal of the coil. The first start-up module is used to provide a first voltage to the coil and the energy storage element. The second start module is connected to the first end of the shut-off module and the first end of the coil. The second start module is used to provide a second voltage to the coil and the energy storage element. A switching control module is connected to the second starting module and the second end of the coil. The switching control module is used to control whether the second starting module provides a second voltage to the coil and / or the energy storage element. A control module is connected to the switching control module, and the control module is used to provide switching signals and control signals to the switching control module.

2. The switching device according to claim 1, characterized in that, The switching control module includes a first switching transistor and a third switching transistor. The first end of the first switching transistor and the first end of the third switching transistor are both connected to the control module. The second ends of the first switching transistor and the second ends of the third switching transistor are both grounded. The third end of the first switching transistor is connected to the anode of the fourth semiconductor element and the second end of the coil, respectively. The third end of the third switching transistor is connected to the second starting module.

3. The switching device according to claim 2, characterized in that, The second start-up module includes a second switching transistor and a first semiconductor element. The first end of the second switching transistor is connected to the third end of the third switching transistor through a second resistor. The second end of the second switching transistor is connected to a DC power supply. The third end of the second switching transistor is connected to the anode of the first semiconductor element. The cathode of the first semiconductor element is connected to the first end of the coil.

4. The switching device according to claim 1, characterized in that, The first startup module includes a DC / DC converter and a second semiconductor element. The input terminal of the DC / DC converter is connected to a DC power supply, the output terminal of the DC / DC converter is connected to the anode of the second semiconductor element, and the cathode of the second semiconductor element is connected to the first end of the coil.

5. The switching device according to claim 3, characterized in that, The first switch, the second switch, and the third switch are all MOSFETs. The gate of the MOSFET serves as the first terminal of the first switch, the second switch, and the third switch; the source of the MOSFET serves as the second terminal of the first switch, the second switch, and the third switch; and the drain of the MOSFET serves as the third terminal of the first switch, the second switch, and the third switch.

6. The switching device according to claim 3, characterized in that, Both the first semiconductor element and the fourth semiconductor element are diodes, with the anode of the diode serving as the anode of both the first and fourth semiconductor elements, and the cathode of the diode serving as the cathode of both the first and fourth semiconductor elements.

7. The switching device according to claim 3 or 4, characterized in that, The DC power supply is also connected to the control module.

8. The switching device according to any one of claims 1-6, characterized in that, The control module includes a microcontroller unit.

9. The switching device according to any one of claims 1-6, characterized in that, The energy storage element is a capacitor.

10. A hybrid inverter and off-grid switching device, characterized in that, The device includes a DC / AC inverter, a first AC electromagnetic interference filter, a first switch, a second switch, a third switch, a fourth switch, a second AC electromagnetic interference filter, and a power grid. The input terminal of the DC / AC inverter is connected to the power supply. The output terminal of the DC / AC inverter is connected to the input terminal of the first AC electromagnetic interference filter. The output terminal of the first AC electromagnetic interference filter is connected to the input terminal of the first switch. The output terminal of the first switch is connected to the input terminals of the second switch and the fourth switch, respectively. The output terminal of the second switch is connected to the input terminal of the third switch. The output terminal of the third switch is connected to the input terminal of the second AC electromagnetic interference filter. The output terminal of the second AC electromagnetic interference filter is connected to the power grid. The output terminal of the fourth switch is connected to the load. The first switch, the second switch, the third switch, and the fourth switch are all switching devices as described in any one of claims 1-9.

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