CN222127659U - Photovoltaic surge protector - Google Patents

Abstract

The utility model discloses a photovoltaic surge protector, and relates to the technical field of surge protection. The photovoltaic power generation device comprises a direct current protection circuit, a thermal tripping module, a reverse current protection module, a multistage protection module and an inversion module, wherein the direct current protection circuit is electrically connected with photovoltaic power generation equipment, the direct current protection circuit is electrically connected with the thermal tripping module, the thermal tripping module is electrically connected with the inversion module, the reverse current protection module is electrically connected with a power supply, the multistage protection module is connected with the direct current protection circuit, the thermal tripping module, the inversion module and the reverse current protection module in parallel, potential damage caused by voltage surge, overheat and countercurrent is effectively prevented through integrating the direct current protection circuit, the thermal tripping module and the reverse current protection module, electromagnetic interference is effectively restrained through a filter circuit and a transient suppression diode, interference of voltage spikes is prevented, and stable operation and clear signal transmission of the electrical equipment are ensured.

Description

Photovoltaic surge protector

Technical Field

The utility model relates to the technical field of surge protection, in particular to a photovoltaic surge protector.

Background

A photovoltaic surge protector is a device for preventing damage caused by voltage surges in a Photovoltaic (PV) system. Voltage surges may be caused by lightning strikes, grid fluctuations, or rapid switching of equipment. Photovoltaic surge protectors are critical to protecting inverters, controllers, and other electrical devices in a photovoltaic system from excessive voltages. The working principle of the photovoltaic surge protector is that the photovoltaic surge protector works by limiting the voltage level passing through equipment, when the surge overvoltage occurs in a power supply system, the power supply surge protector is immediately conducted in nanosecond time, the amplitude of the overvoltage is limited in the safe working range of the equipment, and meanwhile surge energy is released. Then, the surge protector is quickly tripped to be in a high-resistance state, so that the normal power supply of the power supply system is not affected. However, when energy reverse flow, electromagnetic interference and voltage spike occur in the operation process of the photovoltaic system, the existing photovoltaic surge protector cannot effectively protect, and meanwhile, cannot provide effective multistage protection under different voltage scenes.

Disclosure of utility model

Based on the above-mentioned drawbacks of the prior art, an object of the present utility model is to provide a photovoltaic surge protector, so as to solve the above-mentioned technical problems.

In order to achieve the above purpose, the utility model provides a photovoltaic surge protector, which comprises a direct current protection circuit, a thermal tripping module, a reverse current protection module, a multistage protection module and an inversion module, wherein the input end of the direct current protection circuit is electrically connected with the output end of photovoltaic power generation equipment, the output end of the direct current protection circuit is electrically connected with the input end of the thermal tripping module, the output end of the thermal tripping module is electrically connected with the input end of the inversion module, the input end of the reverse current protection module is electrically connected with the output end of the inversion module, the output end of the reverse current protection module is electrically connected with a power supply, and the multistage protection module is parallelly connected with the direct current protection circuit, the thermal tripping module, the inversion module and the reverse current protection module.

The direct current protection circuit further comprises a metal oxide varistor and a gas discharge tube, wherein the metal oxide varistor and the gas discharge tube are connected in parallel, the metal oxide varistor is used for reducing the impedance of the metal oxide varistor and guiding redundant energy to a ground wire when the voltage exceeds the voltage threshold value of the metal oxide varistor, and the gas discharge tube is used for ionizing and conducting gas under the high-voltage condition and processing voltage impact with higher energy.

The utility model further provides that the thermal tripping module comprises a thermal tripping device, wherein the thermal tripping device is used for detecting the internal temperature of equipment, and when the internal temperature reaches a temperature threshold value, a thermal tripping mechanism is triggered to automatically disconnect a circuit, so that the equipment is prevented from being damaged due to overheating.

The utility model is further arranged that the reverse flow protection module comprises a reverse flow detection circuit for preventing reverse flow of energy stored by the power supply into the photovoltaic power generation device.

The utility model further provides that the reverse flow detection circuit comprises a current sensor, a logic circuit and a relay, wherein the current sensor is used for monitoring the direction and the magnitude of current in real time, the logic circuit is used for receiving signals of the current sensor and making judgment according to the direction and the magnitude of the current, and the judgment logic comprises controlling the relay to disconnect the circuit when the reverse flow is detected.

The utility model further provides that the multistage protection module comprises a filter circuit and a transient suppression diode, wherein the filter circuit is used for suppressing electromagnetic interference, the transient suppression diode is used for responding to voltage spikes, and when the voltage exceeds a cliff voltage, the transient suppression diode is conducted in a time of picoseconds to nanoseconds, so as to provide protection path limiting voltage.

The utility model is further arranged that the filter circuit comprises a low-pass filter for removing high-frequency interference from the circuit.

The utility model is further arranged that the inversion module comprises an inverter, and the inversion module is used for converting a direct current power supply into an alternating current power supply.

In summary, the utility model has the following advantages:

1. The system safety and equipment protection are that damage to a photovoltaic system caused by voltage surges is effectively avoided through a metal oxide piezoresistor and a gas discharge tube in a direct current protection circuit, photovoltaic power generation equipment is protected, safety of other electrical equipment connected to the system is ensured, and a thermal tripping module is used for preventing equipment damage or serious safety problems possibly caused by overheating by monitoring temperature and automatically disconnecting when the temperature reaches a set threshold value.

2. The energy efficiency and the system efficiency are that the reverse flow of electric energy is effectively prevented through the reverse flow protection module, the energy utilization efficiency of the system is improved, the energy waste is prevented, the application of the inversion module optimizes the direct current-alternating current energy conversion process, the stability and the efficiency of electric power output are ensured, and the power generation efficiency and the economic benefit of the whole system are improved.

3. Electromagnetic compatibility and signal stability, namely the filter circuit in the multistage protection module effectively inhibits electromagnetic interference, ensures the electromagnetic compatibility of the system, and further improves the adaptability of the system to complex electrical environments by the transient suppression diode to cope with rapid voltage change and peak.

The foregoing description is only an overview of the present application, and is intended to be implemented in accordance with the teachings of the present application in order that the same may be more clearly understood and to make the same and other objects, features and advantages of the present application more readily apparent.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the drawings required for the description of the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present utility model, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art. In the drawings:

fig. 1 is a schematic structural view of the present utility model.

In the figure, a direct current protection circuit, a thermal tripping module, a reverse current protection module, a multistage protection module and an inversion module are shown in the figure, wherein the direct current protection circuit, the thermal tripping module, the reverse current protection module, the multistage protection module and the inversion module are shown in the figure.

Detailed Description

Further advantages and effects of the present utility model will become readily apparent to those skilled in the art from the disclosure herein, by referring to the accompanying drawings and the preferred embodiments. The utility model may be practiced or carried out in other embodiments that depart from the specific details, and the details of the present description may be modified or varied from the spirit and scope of the present utility model. It should be understood that the preferred embodiments are presented by way of illustration only and not by way of limitation.

It should be noted that the illustrations provided in the following embodiments merely illustrate the basic concept of the present utility model by way of illustration, and only the components related to the present utility model are shown in the drawings and are not drawn according to the number, shape and size of the components in actual implementation, and the form, number and proportion of the components in actual implementation may be arbitrarily changed, and the layout of the components may be more complicated.

In the following description, numerous details are set forth in order to provide a more thorough explanation of embodiments of the present utility model, it will be apparent, however, to one skilled in the art that embodiments of the present utility model may be practiced without these specific details, in other embodiments, well-known structures and devices are shown in block diagram form, rather than in detail, in order to avoid obscuring the embodiments of the present utility model.

Hereinafter, an embodiment of the present utility model will be described in accordance with its entire structure.

The photovoltaic surge protector comprises a direct current protection circuit 1, a thermal tripping module 2, a reverse current protection module 3, a multi-stage protection module 4 and an inversion module 5, wherein the input end of the direct current protection circuit 1 is electrically connected with the output end of photovoltaic power generation equipment, the output end of the direct current protection circuit 1 is electrically connected with the input end of the thermal tripping module 2, the output end of the thermal tripping module 2 is electrically connected with the input end of the inversion module 5, the input end of the reverse current protection module 3 is electrically connected with the output end of the inversion module 5, the output end of the reverse current protection module 3 is electrically connected with a power supply, and the multi-stage protection module 4 is connected with the direct current protection circuit 1, the thermal tripping module 2, the inversion module 5 and the reverse current protection module 3 in parallel; specifically, the direct current protection circuit 1 is a first defending line of a photovoltaic surge protector and is used for processing voltage surge of direct current from photovoltaic power generation equipment, the influence of voltage surge on a subsequent circuit is effectively reduced by connecting a metal oxide piezoresistor and a gas discharge tube, the thermal tripping module 2 is used for automatically cutting off the circuit when abnormal high temperature is detected and protecting equipment from damage, the inversion module 5 is used for converting the direct current into alternating current and supplying the alternating current to a power grid or a load, the reverse current protection module 3 is used for preventing current reversely flowing from the power grid or other power sources to the photovoltaic power generation equipment and protecting a photovoltaic panel and other components from damage, the multistage protection module 4 comprises a filter circuit and a transient suppression diode and is used for effectively suppressing electromagnetic interference and responding voltage spikes, so that the stability and the safety of the system are further enhanced, not only can the threat from the natural environment be handled, but also the problems created by the inside of the system (including reverse flow and overheating), the parallel connected multi-stage protection modules ensure that protection is obtained even if the primary protection path fails.

The utility model further provides that the direct current protection circuit 1 comprises a metal oxide varistor and a gas discharge tube, wherein the metal oxide varistor and the gas discharge tube are connected in parallel, the metal oxide varistor is used for reducing the impedance of the metal oxide varistor and guiding redundant energy to a ground wire when the voltage exceeds the voltage threshold value of the metal oxide varistor, the gas discharge tube is used for ionizing and conducting gas under the condition of high voltage so as to treat voltage impact with higher energy, and particularly, the Metal Oxide Varistor (MOV) and the Gas Discharge Tube (GDT) realize double protection on a photovoltaic system, the protection effect of the direct current protection circuit is optimized, the stability and the safety of the photovoltaic system in the face of various voltage impact are ensured, the Metal Oxide Varistor (MOV) has higher resistance under normal working voltage and does not influence the normal working of the circuit, when the voltage surge is met, the resistance value of the MOV is rapidly reduced, a low impedance path is formed and the excessive voltage is guided to the ground wire, so that the protection circuit is prevented from being damaged, the MOV is suitable for treating the voltage impact with relatively low energy level and the gas impact is almost not influenced by the normal working condition of the circuit under the condition that the gas impact is opened on the circuit. Only when the voltage rises to a level sufficient to ionize the gas in the tube will the GDT conduct, the ionization process creates a low impedance path that rapidly directs current to ground, protecting the circuit from extremely high voltages. The GDT is suitable for handling high energy voltage surges beyond the protection range of the MOV, provides graded protection through the combination of the MOV and the GDT, can effectively cope with voltage surges from middle to extremely high energy levels, and can quickly respond and limit the voltage surges, while the GDT provides a safe protection threshold for the system to cope with more extreme voltage conditions.

The utility model further provides that the thermal tripping module 2 comprises a thermal tripping device, wherein the thermal tripping device is used for detecting the internal temperature of equipment, when the internal temperature reaches a temperature threshold value, a thermal tripping mechanism is triggered, a circuit is automatically disconnected, and equipment damage caused by overheat is prevented, and particularly, the thermal tripping module 2 comprises the thermal tripping device, so that the temperature monitoring and overheat protection capability of a photovoltaic system are enhanced, the internal temperature of the equipment is monitored in real time, and the circuit is automatically cut off when the temperature reaches a preset threshold value, so that equipment damage or serious potential safety hazard possibly caused by overheat is effectively prevented.

The present utility model further provides that the reverse flow protection module 3 includes a reverse flow detection circuit for preventing the energy stored by the power supply from flowing reversely into the photovoltaic power generation device, and in particular, the reverse flow protection module 3 includes a reverse flow detection circuit for enhancing the protection capability of the photovoltaic system against the reverse flow phenomenon, which generally occurs when the photovoltaic system is connected to the power grid or has a battery for storage, and when the power flow direction of the system is opposite to the normal condition, that is, the power flow from the power grid or the battery to the photovoltaic panel, damage may be caused to the photovoltaic panel or other system components.

The utility model further provides a reverse flow detection circuit, which comprises a current sensor, a logic circuit and a relay, wherein the current sensor is used for monitoring the direction and the magnitude of current in real time, the logic circuit is used for receiving signals of the current sensor and making judgment according to the direction and the magnitude of the current, the judgment logic comprises a control relay disconnection circuit when reverse flow is detected, the current sensor is specifically used for monitoring the direction and the magnitude of the current in real time and can quickly identify the current backflow condition, the logic circuit is used for receiving the signals of the current sensor and analyzing the direction and the magnitude of the current to determine whether the backflow phenomenon exists, and the relay is responsible for actual disconnection control according to the judgment of the logic circuit. When the reverse flow is detected, the relay is operated to open the circuit, thereby preventing the reverse flow from further occurring.

The utility model further provides that the multistage protection module 4 comprises a filter circuit and a transient suppression diode, wherein the filter circuit is used for suppressing electromagnetic interference, the transient suppression diode is used for responding to voltage spike, when the voltage exceeds the cliff voltage, the transient suppression diode is conducted in picoseconds to nanosecond level to provide protection path limiting voltage, the filter circuit comprises a low-pass filter which is used for removing high-frequency interference from the circuit, the low-pass filter is used for effectively removing high-frequency interference on a power line or a signal line through combination of a capacitor, an inductor and a resistor, allowing low-frequency signals to pass, blocking or weakening high-frequency noise, ensuring normal operation of the photovoltaic system, and the transient suppression diode (TVS diode) is rapidly conducted when the voltage suddenly exceeds the designed cliff voltage (namely a protection voltage threshold value), provides a low-impedance path to rapidly guide excessive voltage to a ground wire or a reverse guide source, so that sensitive electronic components are protected from damage caused by transient high-voltage shock, and the rapid response time (usually within picoseconds to nanosecond range) of the TVS diode is suitable for switching or other sudden voltage spike-resistant events.

The utility model is further arranged that the inverter module 5 comprises an inverter, wherein the inverter module 5 is used for converting direct current power supply into alternating current power supply, and in particular, the inverter module 5 is used for converting Direct Current (DC) power supply into Alternating Current (AC) power supply, so that the power generated by the photovoltaic power generation equipment can be effectively supplied to a power grid or directly used for various electrical equipment.

The direct current protection circuit monitors and protects the current when the direct current generated by the photovoltaic panel flows to the inversion module, if the voltage exceeds the threshold value of a Metal Oxide Varistor (MOV), the impedance of the MOV drops sharply, redundant electric energy is rapidly led to a ground wire to prevent damage to subsequent equipment caused by voltage surges, when higher voltage surges are encountered, a Gas Discharge Tube (GDT) is activated, gas in the gas discharge tube is ionized and conducted to form a low-impedance path to rapidly lead excessive current to the ground wire to treat high-energy voltage surges, the thermal tripping module monitors the internal temperature of the system in real time through a built-in thermal tripping device, and once the internal temperature exceeds a preset safety threshold value, the thermal tripping device is automatically triggered to disconnect the circuit to prevent equipment damage or fire risks caused by overheating. The reverse current detection circuit in the reverse current protection module monitors the direction and the magnitude of current in real time by using a current sensor, if the current is detected to flow reversely, the logic circuit judges and instructs the relay to disconnect the circuit, reverse energy flow from a power grid or energy storage equipment to a photovoltaic panel is prevented, the photovoltaic power generation equipment is protected, the multistage protection module comprises a filter circuit and a transient suppression diode (TVS diode), the filter circuit suppresses electromagnetic interference through a low-pass filter, the stable operation of the system is ensured, when the voltage is subjected to peak exceeding the cliff voltage of the TVS diode, the TVS diode is rapidly conducted, the voltage is limited in an extremely short time (picosecond to nanosecond level), the system is protected from transient overvoltage, and the inversion module comprises an inverter for converting direct current generated by the photovoltaic panel into alternating current, and the power grid uses or directly drives various alternating current loads.

Although embodiments of the utility model have been shown and described, the detailed description is to be construed as exemplary only and is not limiting of the utility model as the particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples, and modifications, substitutions, variations, etc. may be made in the embodiments as desired by those skilled in the art without departing from the principles and spirit of the utility model, provided that such modifications are within the scope of the appended claims.

Claims (8)

1. The utility model provides a photovoltaic surge protector, includes direct current protection circuit (1), thermal tripping module (2), reverse current protection module (3), multistage protection module (4) and contravariant module (5), its characterized in that, the input of direct current protection circuit (1) and photovoltaic power generation equipment's output electric connection, the output of direct current protection circuit (1) and thermal tripping module (2) input electric connection, thermal tripping module (2) output with contravariant module (5) input electric connection, reverse current protection module (3) input with contravariant module (5) output electric connection, reverse current protection module (3) output and power electric connection, multistage protection module (4) with direct current protection circuit (1), thermal tripping module (2), contravariant module (5) and reverse current protection module (3) parallel connection.

2. A photovoltaic surge protector according to claim 1, characterized in that the dc protection circuit (1) comprises a metal oxide varistor and a gas discharge tube, the metal oxide varistor being connected in parallel with the gas discharge tube, the metal oxide varistor being adapted to reduce the impedance of the metal oxide varistor when the voltage exceeds the voltage threshold of the metal oxide varistor, to direct excess energy to ground, the gas discharge tube being adapted to ionize and conduct gas under high voltage conditions, to handle higher energy voltage shocks.

3. A photovoltaic surge protector according to claim 1, characterized in that the thermal trip module (2) comprises a thermal trip for detecting the internal temperature of the device, triggering a thermal trip mechanism when the internal temperature reaches a temperature threshold, automatically opening the circuit, preventing the damage of the device due to overheating.

4. A photovoltaic surge protector according to claim 1, characterized in that the reverse flow protection module (3) comprises a reverse flow detection circuit for preventing reverse flow of the energy stored by the power supply into the photovoltaic power generation device.

5. The photovoltaic surge protector of claim 4, wherein the reverse flow detection circuit comprises a current sensor for monitoring the direction and magnitude of the current in real time, a logic circuit for receiving the signal from the current sensor and making a determination based on the direction and magnitude of the current, and a relay, wherein the determination logic comprises controlling the relay to open the circuit when reverse flow is detected.

6. A photovoltaic surge protector according to claim 1, characterized in that the multi-stage protection module (4) comprises a filter circuit for suppressing electromagnetic interference and a transient suppression diode for responding to voltage spikes, the transient suppression diode being turned on in picoseconds to nanosecond level when the voltage exceeds the cliff voltage, providing a protection path limiting voltage.

7. A photovoltaic surge protector according to claim 6 wherein the filtering circuit includes a low pass filter for removing high frequency interference from the circuit.

8. A photovoltaic surge protector according to claim 1, characterized in that the inverter module (5) comprises an inverter, the inverter module (5) being adapted to convert a direct current power supply into an alternating current power supply.