Apparatus for performing security function and solar power generation system including same

Abstract

An apparatus for performing a secure function according to one aspect includes an electronic circuit and a processor. The electronic circuit includes a switching element, a first resistor, and a second resistor. The processor controls operation of the electronic circuit such that a first voltage applied to the electronic circuit is converted to a second voltage when a predetermined condition is satisfied.

Description

Technical Field

[0001] This disclosure relates to an apparatus for performing safety functions and a photovoltaic power generation system including the apparatus. Background Technology

[0002] Photovoltaic (PV) power generation systems should ensure stability by real-time assessment of potential anomalies and emergencies during system operation. In emergencies, PV systems should have safety features that, for safety, interrupt the output of the photovoltaic (PV) modules and, depending on national and product requirements, control the voltage to or below a safe voltage for a specific period. Therefore, with the increasing diversification of global industrial safety standards, the demand for rapid shutdown (RSD) functionality in PV power generation systems is growing.

[0003] Meanwhile, module-level power conversion devices (or module-level power control devices) (hereinafter referred to as module-level power electronics (MLPE)) are introduced into photovoltaic power generation systems to improve the performance of PV modules and increase power generation efficiency.

[0004] At the same time, there is a need to introduce a device that can stably output a safe voltage even in emergency situations, perform safety functions, and is easy to implement. Summary of the Invention

[0005] Technical issues

[0006] This disclosure provides an apparatus for performing safety functions and a photovoltaic power generation system including the apparatus, which are capable of performing safety functions more stably in emergency situations.

[0007] This disclosure provides an apparatus for performing security functions and a photovoltaic power generation system including the apparatus, which can easily perform security functions without any complex circuit configuration (e.g., integrated circuits).

[0008] Solution to the problem

[0009] According to one aspect, an apparatus for performing a safety function includes: an electronic circuit comprising a switching element, a first resistor, and a second resistor; and a processor configured to control the operation of the electronic circuit such that, under certain conditions, a first voltage applied to the electronic circuit is converted into a second voltage.

[0010] According to another aspect, a photovoltaic power generation system includes: a plurality of photovoltaic (PV) modules; and an apparatus connected to each of the plurality of PV modules; wherein the apparatus includes: an electronic circuit including a switching element, a first resistor, and a second resistor; and a processor configured to control the electronic circuit such that a first voltage applied to the electronic circuit is converted into a second voltage according to the state of the photovoltaic power generation system.

[0011] Beneficial effects of the invention

[0012] Because a resistor is used to output a safe voltage, the safety function can be safely implemented without any complicated circuit configuration.

[0013] The level of the safe voltage can be easily adjusted or set based on the forward characteristic of the diode.

[0014] The device performing the safety function can operate stably without placing any burden on the overall system, such as power loss.

[0015] A safe voltage can be output using simple semiconductor characteristics without any complicated process of setting the safe voltage through PWM controller control.

[0016] Because it outputs a safe voltage with only a simple circuit configuration, it can solve the problem of voltage control instability caused by complex control algorithms and defects in semiconductor integrated circuits.

[0017] Since the level of the safety voltage can be configured based on the simple forward characteristic of the diode, the circuit can be flexibly modified according to the user's safety requirements. Attached Figure Description

[0018] Figure 1 This is a diagram illustrating an example of a photovoltaic power generation system according to an embodiment.

[0019] Figure 2 This is a block diagram illustrating an example of a device for performing a security function according to an embodiment.

[0020] Figure 3 This is a diagram illustrating an example of an electronic circuit according to an embodiment.

[0021] Figure 4 This is a diagram illustrating another example of an electronic circuit according to an embodiment.

[0022] Figure 5 This is a diagram illustrating an example of the operation of a device for performing security functions according to an embodiment. Detailed Implementation

[0023] Best way to implement this disclosure

[0024] According to one aspect, an apparatus for performing a safety function includes: an electronic circuit comprising a switching element, a first resistor, and a second resistor; and a processor for controlling the operation of the electronic circuit such that, under certain conditions, a first voltage applied to the electronic circuit is converted into a second voltage.

[0025] Method of implementing this disclosure

[0026] The terminology used in the various embodiments is selected from commonly used terms as much as possible; however, these terms may vary depending on the intent of an engineer working in the field, case law, the emergence of new technologies, etc. Furthermore, in certain cases, there are terms arbitrarily chosen by the applicant, and in these cases, the meaning of these terms will be described in detail in the relevant descriptive sections. Therefore, the terminology used in the specification should be defined based on the meaning of the term and the overall content of the specification, rather than simply based on the name of the term.

[0027] Throughout this specification, unless otherwise stated, when a part is referred to as "comprising" a component, it does not mean that the part does not include other components, but rather that the part may include other components.

[0028] In addition, terms including ordinal numbers (such as "first", "second", etc.) used in the specification may be used to describe various components, but these components should not be limited by these terms. These terms can be used to distinguish one component from another.

[0029] Preferred embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. The detailed description disclosed below, together with the accompanying drawings, is intended to illustrate exemplary embodiments of the present disclosure and is not intended to represent the only embodiments in which the present disclosure may be practiced. For clarity of the disclosure in the drawings, parts unrelated to the description may be omitted, and throughout the specification, the same reference numerals may be used for the same or similar parts.

[0030] Figure 1 This is a diagram illustrating an example of a photovoltaic power generation system according to an embodiment.

[0031] Reference Figure 1 The photovoltaic power generation system 1 may include PV module 110 and device 120. Meanwhile, in addition to Figure 1 In addition to the components shown, System 1 may also include other general-purpose components.

[0032] PV module 110 can be a module that generates electricity using solar energy. For example, PV modules 110 can be included in system 1 in a plurality of forms.

[0033] Device 120 may be a device that converts the output voltage of PV module 110, to a predefined safe voltage in the event of an emergency, wherein PV module 110 is connected to device 120. See also... Figures 2 to 4 An example of a device 120 that performs safety functions is described.

[0034] For example, device 120 may be an MLPE or a device connected to an MLPE. Alternatively, device 120 may be a device included in an MLPE. Here, the MLPE may be an optimizer or a microinverter.

[0035] As an example, if the MLPE is an optimizer, system 1 may include a single inverter. In this case, the single MLPE may be connected to a single PV module 110, and the MLPE may optimize the power output from the PV module 110 to output it to a single inverter (e.g., a string inverter). The current converted by the inverter (e.g., from DC to AC) may be output to a load or the grid.

[0036] like Figure 1 As shown, a single device 120 can be connected to a single PV module 110, but is not limited thereto. For example, depending on the structure adopted by the photovoltaic power generation system 1, the PV modules 110 and devices can be connected to each other in a many-to-one or many-to-many manner, and the connection form is not limited to any one of them. In another embodiment, the system 1 can be configured in the form of multiple groups connected in series with each other, the group consisting of n PV modules 110 and n devices 120 (n is a natural number equal to or greater than 2).

[0037] In addition, although Figure 1 The photovoltaic power generation system 1 may include an MLPE, an inverter, or a power grid, though it is not shown in the diagram.

[0038] Device 120 can share resources such as the processor built into the MLPE. Accordingly, the MLPE can be connected to the PV module 110 in a one-to-one correspondence, but is not limited thereto. For example, depending on the structure adopted by the photovoltaic power generation system 1, the PV module 110 and the MLPE can be connected to each other in a many-to-one or many-to-many manner, and the connection form is not limited to any one of them.

[0039] For example, if the MLPE is an optimizer, the inverter can be set in a power conversion system (PCS) to perform power conversion, thereby supplying the power generated by the PV module 110 to the load or the grid.

[0040] Device 120, MLPE, or inverter can analyze various data received from PV module 110, MLPE, load, power grid, etc., to monitor the operating status of system 1. In the event of an abnormal situation during monitoring, i.e., when it is necessary to switch to a safe mode, device 120 can output a safe voltage.

[0041] With the MLPE included in System 1, the output voltage of the PV module 110 can be converted to a safe voltage by controlling the switching elements of the buck converter. In this case, a pulse width modulation (PWM) controller should be provided to control the switching elements. Therefore, in the event of a PWM controller failure or an error in the control algorithm, the safe voltage may not be accurately output or controlled. Furthermore, because the PWM controller and switching elements are typically implemented in integrated circuits (ICs), the control and circuit implementation of the PWM controller and switching elements may not be straightforward.

[0042] Meanwhile, in the absence of an MLPE in System 1, the output voltage of PV module 110 can be converted to a safe voltage by controlling a separate regulator (such as a low-dropout (LDO) regulator). However, even with a regulator, the control and circuit implementation of the regulator may not be simple because it is implemented using semiconductor integrated circuits (ICs).

[0043] In this disclosure, an apparatus 120 is proposed that can reliably perform security functions according to standards and can easily perform security functions without the use of any complex configuration such as integrated circuits.

[0044] In the following, the configuration and operation of the apparatus 120 according to an embodiment of the present disclosure will be described in detail with reference to the accompanying drawings.

[0045] Figure 2 This is a block diagram illustrating an example of a device for performing a security function according to an embodiment.

[0046] Reference Figure 2 The device 120 may include electronic circuitry 121 and processor 122.

[0047] Electronic circuit 121 can convert the output voltage of PV module 110 into a safe voltage. (See reference...) Figure 3 and Figure 4 Examples of electronic circuit 121 are described.

[0048] The processor 122 can control the electronic circuit 121 according to the state of the photovoltaic power generation system 1. For example, the processor 122 can control the electronic circuit 121 under certain conditions. Here, the specific conditions may refer to a state where the output voltage of the PV module 110 is output inappropriately as is. For example, the specific conditions may refer to a state where switching to a safe mode may be necessary.

[0049] For example, processor 122 may be a processor provided separately for the purpose of performing security functions, but is not limited thereto. For example, processor 122 may be a processor included in an MLPE. When processor 122 is a processor included in an MLPE, the configuration of device 120 can be further simplified and the manufacturing cost of the device can be reduced. Hereinafter, for ease of explanation, processor 122 will be described as a processor included in an MLPE.

[0050] For example, processor 122 may include a microcontroller unit (MCU) for power control. Processor 122 can control components (e.g., hardware or software components) included in device 20 or MLPE by executing software (e.g., programs, etc.), and processor 122 can process various data or perform calculations.

[0051] For example, processor 122 can perform serial communication with the inverter, or processor 122 can perform power line communication (PLC) to receive control signals, shutdown signals, etc. required for power optimization.

[0052] For example, processor 122 may receive a shutdown signal from an inverter that monitors the overall operating status of photovoltaic power generation system 1, but is not limited thereto.

[0053] For example, processor 122 can monitor the operating status of MLPE to detect abnormal conditions and generate a shutdown signal. Specifically, processor 122 can analyze the operating data of MLPE or various data received from PV module 110, load, power grid, etc. to monitor the operating status, and processor 122 can generate a shutdown signal when an abnormal condition occurs.

[0054] Figure 3 This is a diagram illustrating an example of an electronic circuit according to an embodiment.

[0055] Reference Figure 3 When switched to safe mode, electronic circuit 1211 can control the output voltage V of PV module 110. PV Convert to safe voltage V 安全电压 (V safety voltageThen output a safe voltage V. 安全 Voltage.

[0056] Electronic circuit 1211 may include a switching element SW, a first resistor R1, and a second resistor R2. For example, the switching element SW and the first resistor R1 may be connected in parallel, and the second resistor R2 may be connected in series to the parallel connection between the switching element SW and the first resistor R1.

[0057] At this point, the position of the parallel connection between the switching element SW and the first resistor R1 relative to the position of the second resistor R2 is not limited to any one of these positions. For example, besides... Figure 3 In addition to the electronic circuit 1211 shown, the parallel connection between the switching element SW and the first resistor R1 can also be arranged on the line connected to the positive (+) output terminal of the PV module 110.

[0058] For example, the switching element SW can be implemented as a field-effect transistor (FET), a bipolar junction transistor (BJT), etc., but is not limited to these. In other words, any element that can be turned on or off under the control of the processor 122 can be considered as a switching element SW without restriction.

[0059] The processor 122 can control the electronic circuit 1211 according to the state of the photovoltaic power generation system 1. For example, the processor 122 can control the electronic circuit 121 when certain conditions are met. For example, when it is necessary to switch to a safe mode, the processor 122 can input a cut-off signal to the switching element SW (i.e., disconnect the switching element SW).

[0060] When the switching element SW is disconnected, the output voltage V applied to the electronic circuit 1211 by the PV module 110... pv The resistors can be distributed proportionally to the resistance values ​​of the first resistor R1 and the second resistor R2. Therefore, when the switching element SW is turned off, the electronic circuit 1211 can output a safe voltage across the second resistor R2.

[0061] In other words, the voltage across the second resistor R2 is output as a safe voltage V. 安全电压 Therefore, the resistance values ​​of the first resistor R1 and the second resistor R2 can be determined by considering the standard for the safe voltage output of System 1 and the structure of System 1. Here, the resistance value of the first resistor R1 can be equal to or greater than the resistance value of the second resistor R2. For example, the resistance value of the first resistor R1 can be much larger than the resistance value of the second resistor R2.

[0062] As described above, since the processor 122 uses a resistor to output a safe voltage through a simple principle known as the voltage distribution law, the safety function can be safely performed even if the electronic circuit 1211 does not include complex circuitry.

[0063] In addition, by using electronic circuit 1211, the instability problem of safe voltage control caused by existing complex control algorithms and defects in semiconductor integrated circuits (ICs) can be solved.

[0064] Furthermore, even when the output voltage range of the PV module 110 is high, the safe voltage can be controlled using only the resistor distribution of the processor 122.

[0065] Figure 4 This is a diagram illustrating another example of an electronic circuit according to an embodiment.

[0066] Will Figure 3 and Figure 4 Comparing them, Figure 4 The electronic circuit 1212 can be different from Figure 3 The electronic circuit 1211, because Figure 4 The electronic circuit 1212 also includes a diode D. Therefore, the first resistor R1, the second resistor R2, and the switching element SW of the electronic circuit 1212 can be connected to... Figure 3 These components are the same as those in electronic circuit 1211, and therefore specific descriptions are omitted.

[0067] Diode D can be connected in series with the switching element SW and the first resistor R1 in parallel, and in series with the second resistor R2.

[0068] and Figure 3 Similarly, the position of the parallel connection of the switching element SW and the first resistor R1 relative to the position of the series connection of the second resistor R2 and the diode D is not limited to any one of these positions. For example, besides Figure 4 In addition to the electronic circuit 1212 shown, the parallel connection between the switching element SW and the first resistor R1 can also be arranged on the line connected to the positive (+) output terminal of the PV module 110. Furthermore, the positions of the second resistor R2 and the diode D are not limited to... Figure 4 The arrangement of the second resistor R2 and the diode D can be interchangeable.

[0069] As referenced above Figure 3 When it is necessary to switch to a safe mode, the processor 122 can input a cut-off signal to the switching element SW (i.e., disconnect the switching element SW).

[0070] When the switching element SW is disconnected, the output voltage V applied to the electronic circuit 1212 by the PV module 110...pv The resistors can be allocated proportionally to the resistance values ​​of the first resistor R1, the second resistor R2, and the diode D.

[0071] At this time, the safe voltage V 安全电压 It can be the sum of the forward voltage of diode D and the voltage distributed to the second resistor R2. That is, when the switching element SW is turned off, the electronic circuit 1212 can output a safe voltage across the opposite ends of the second resistor R2 and diode D.

[0072] Therefore, the resistance values ​​of the first resistor R1 and the second resistor R2 can be determined by considering the resistance value of the diode D, the standard for the safe voltage output of system 1, and the structure of system 1. Furthermore, the resistance value of the first resistor R1 can be equal to or greater than the resistance value of the second resistor R2. For example, the resistance value of the first resistor R1 can be much larger than the resistance value of the second resistor R2.

[0073] Furthermore, depending on the characteristics of the product (such as manufacturer, materials, etc.), the PV module 110 can have different output voltages V. pv (In particular, the maximum output voltage V) oc Therefore, the output voltage V applied to the device 120 by the PV module 110 is... pv The range can vary depending on the type of PV module 110.

[0074] When the device 120 includes a diode D, since the forward voltage of the diode D is constant, the device 120 can stably output the required safe voltage V regardless of the manufacturer or product characteristics of the PV module 110. 安全电压 .

[0075] As described above, since electronic circuit 1212 is a circuit implemented using the simple semiconductor characteristics of a diode, the level of the safe voltage can be easily adjusted and set according to the forward characteristics of diode D.

[0076] In addition, since the voltage across diode D is constant, a safe voltage can be easily output regardless of the type of PV module 110.

[0077] Furthermore, a safe voltage can be output using simple semiconductor characteristics without any complex process of setting the safe voltage through PWM controller control.

[0078] Furthermore, since the required safety voltage level can be configured based on the simple forward characteristics of the diode, the circuit can be flexibly modified according to the user's safety requirements.

[0079] Figure 5This is a diagram illustrating an example of the operation of a device for performing security functions according to an embodiment.

[0080] In S10, the processor 122 can determine whether it is necessary to switch to safe mode. In other words, the processor 122 can determine whether certain conditions are met.

[0081] For example, processor 122 can monitor the status of system 1 to determine whether it is necessary to switch to safe mode based on whether an abnormal condition occurs. Here, safe mode may include RSD mode.

[0082] Alternatively, upon receiving a shutdown signal from the inverter, the processor 122 can determine that it needs to switch to a safe mode.

[0083] Additionally, device 120 can be used to determine if the MLPE has failed. In this case, system 1 can be switched to safe mode by an administrator (e.g., an installer), and the failure of the MLPE can be confirmed by the safe voltage output by device 120.

[0084] If the processor 122 determines that the system 1 needs to switch to safe mode ("Yes" in S10), the processor 122 may input a cut-off signal to the switching element SW.

[0085] When the switching element SW is turned off, electronic circuit 1211 can output a safe voltage across the second resistor R2, or electronic circuit 1212 can output a safe voltage across the opposite ends of the second resistor R2 and diode D.

[0086] If the processor 122 determines that system 1 does not need to switch to safe mode ("No" in S10), the algorithm can terminate. In other words, under normal operation of system 1, the switching elements SW of electronic circuits 1211 and 1212 can be turned on.

[0087] When the switching element SW is turned on, the switching element SW can have on-resistance (RDS(ON)), which is the resistance value between the drain and the source.

[0088] Since the first resistor R1 and the switching element SW are connected in parallel, the composite resistor can have a value less than RDS(ON), so the output voltage of the PV module 110 can be directly applied to the opposite ends of the second resistor R2. That is, when the switching element SW is turned on, the device performing the safety function 120 can not affect system 1.

[0089] As described above, device 120 can operate stably without burdening system 1, such as causing power loss.

[0090] Furthermore, the methods described above can be written as programs executable on a computer and implemented on a general-purpose digital computer that runs the program using a computer-readable recording medium. Additionally, the structure of the data used in the methods described above can be recorded on a computer-readable recording medium in various ways. Computer-readable recording media can include storage media, such as magnetic storage media (e.g., ROM, RAM, USB, floppy disk, hard disk, etc.) and optically readable media (e.g., CD-ROM, DVD, etc.).

[0091] Those skilled in the art related to the embodiments will understand that this disclosure can be implemented in modified forms without departing from the essential features described above. Therefore, the disclosed methods should be considered illustrative rather than restrictive, and the scope of the claims is not embodied in the foregoing description but rather in the scope of the claims, which should be interpreted to include all differences falling within the scope of their equivalents.

Claims

1. An apparatus for performing a safety function, comprising: An electronic circuit, the electronic circuit including a switching element, a first resistor and a second resistor; as well as A processor configured to control the operation of the electronic circuit such that, under certain conditions, a first voltage applied to the electronic circuit is converted into a second voltage.

2. The apparatus according to claim 1, wherein The processor is also configured to convert the first voltage to the second voltage by disconnecting the switching element.

3. The apparatus according to claim 1, wherein The first voltage includes the output voltage of at least one photovoltaic (PV) module, which is included in the photovoltaic power generation system.

4. The apparatus according to claim 1, wherein The switching element is connected in parallel with the first resistor, and The second resistor is connected in series to the parallel connection between the switching element and the first resistor.

5. The apparatus according to claim 1, wherein The electronic circuit also includes a diode connected in series with the second resistor, and The processor is further configured to convert the first voltage to the second voltage by disconnecting the switching element, wherein The second voltage includes the voltage across the opposite ends of the second resistor and the diode.

6. The apparatus according to claim 1, wherein The processor is also configured to monitor the status of the photovoltaic power generation system to determine whether the specific conditions are met.

7. The apparatus according to claim 1, wherein The specific conditions include the following: the photovoltaic power generation system needs to be switched to safe mode.

8. The apparatus according to claim 1, wherein The resistance value of the first resistor is equal to or greater than the resistance value of the second resistor.

9. A photovoltaic power generation system, comprising: Multiple photovoltaic (PV) modules; as well as The device is connected to each of the plurality of PV modules; in The device includes: An electronic circuit, the electronic circuit including a switching element, a first resistor and a second resistor; as well as A processor configured to control the electronic circuitry such that a first voltage applied to the electronic circuitry is converted into a second voltage according to the state of the photovoltaic power generation system.

10. The system according to claim 9, wherein The processor is also configured to convert the first voltage to the second voltage by disconnecting the switching element.

11. The system according to claim 9, wherein The first voltage includes the output voltage of at least one PV module, which is included in the photovoltaic power generation system.

12. The system according to claim 9, wherein The switching element is connected in parallel with the first resistor, and The second resistor is connected in series to the parallel connection between the switching element and the first resistor.

13. The system according to claim 9, wherein The electronic circuit also includes a diode connected in series with the second resistor, and The processor is further configured to convert the first voltage to the second voltage by disconnecting the switching element, wherein The second voltage includes the voltage across the opposite ends of the second resistor and the diode.

14. The system according to claim 9, wherein The processor is also configured to monitor the status of the photovoltaic power generation system to determine whether certain conditions are met.

15. The system according to claim 9, wherein The resistance value of the first resistor is equal to or greater than the resistance value of the second resistor.

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