Abstract: A rapid shutdown system and a method for controlling the rapid shutdown system are provided. A disturbance is applied to a direct-current side of an inverter in the rapid shutdown system only when the inverter does not meet a starting condition, i.e., before the inverter starts. Once meeting the starting condition, the inverter normally operates. A shutdown device in the rapid shutdown system determines its state by determining whether the electrical signal at its output end meets the preset condition, and switches itself on or off in response to its determination.

Abstract: A rapid shutdown system and a method for controlling the rapid shutdown system are provided. For each of shutdown devices in the rapid shutdown system, an electrical signal disturbance is applied to a direct current bus connected to the shutdown device at least once within each pre-shutdown period of the shutdown device, by an inverter in the rapid shutdown system operating in a mode of limited power output. Then, the shutdown device samples its input parameter and/or output parameter and determines, based on the sampled input parameter and/or the sampled output parameter, whether the electrical signal disturbance applied to the direct current bus meets a preset condition. The shutdown device switches itself on or remains in an ON state in response to a determination result that the electrical-signal disturbance already meets the preset condition.

Abstract: A micro inverter having a plurality of independent inputs and a photovoltaic system are provided. The micro inverter includes multiple isolated DC-DC converters and a DC-AC converter. Each isolated DC-DC converter of the isolated DC-DC converters includes an inverter H-bridge, a transformer and a voltage-multiplying rectifier. An input terminal of the inverter H-bridges is configured to connect to a direct-current power supply. A secondary winding of the transformer is connected to an input terminal of the voltage-multiplying rectifier. An output terminal of the voltage-multiplying rectifier is connected to an input terminal of the DC-AC converter. A leakage inductor or an external inductor of the transformer forms series resonance along with a capacitor in the voltage-multiplying rectifier.

Abstract: A single-stage multi-path direct current access converter and a control method thereof are provided. The single-stage multi-path direct current access converter includes an AC-side conversion circuit; at least two DC-side conversion circuits; and transformers corresponding to the at least two DC-side conversion circuits. AC sides of the at least two DC-side conversion circuits are respectively connected to primary windings of the corresponding transformers; secondary windings of the transformers are connected in parallel to a first side of the AC-side conversion circuit; each of the at least two DC-side conversion circuits is configured to invert DC power received by the DC-side conversion circuit, or to rectify AC power received by the DC-side conversion circuit; and the AC-side conversion circuit is configured to perform AC frequency conversion.

Abstract: A start method for a photovoltaic rapid shutdown system, an application apparatus and a system. In the method, an inverter system controls the voltage change of a corresponding direct current bus in a photovoltaic rapid shutdown system; and a photovoltaic module shutdown device performs determination according to a measured output voltage of itself, and controls itself to be turned on when the change characteristic of the voltage of the direct current bus connected to itself satisfies a preset turn-on condition. Therefore, merely by means of a self-contained voltage sampling device, the photovoltaic module shutdown device can determine whether a turn-on signal is received, without additionally providing a corresponding receiving device, thereby reducing hardware cost of the photovoltaic module shutdown device while realizing communication between the photovoltaic module shutdown device and the outside.

Abstract: A method for starting a photovoltaic rapid shutdown system, an application apparatus and a system are provided. In this method, the inverter system controls a voltage of a direct current bus in the photovoltaic rapid shutdown system. The photovoltaic module breaker makes determination based on a detected output voltage of the photovoltaic module breaker. In a case that the change characteristics of the voltage of the direct current bus connected to the photovoltaic module breaker meets the predetermined turn-on condition, the photovoltaic module breaker controls itself to be turned on. Therefore, the photovoltaic module breaker can determine whether the photovoltaic module breaker receives a turn-on signal only based on its own voltage acquisition device without an additional receiving apparatus.

Abstract: A method for controlling a photovoltaic rapid shutdown system, an inverting system, and a photovoltaic rapid shutdown system. In the photovoltaic rapid shutdown system, the inverting system determines whether the photovoltaic rapid shutdown system is to enter a safe mode, introduces fluctuations onto a direct-current bus in the photovoltaic rapid shutdown system in response to the photovoltaic rapid shutdown system being not to enter the safe mode, and otherwise does not introduce the fluctuations onto the direct-current bus. A shutdown device for a photovoltaic module determines according to an output parameter thereof whether an electrical parameter on the direct-current bus connected to the shutdown device meets a preset condition, controls itself to be turned on or maintains itself being on in response to the electrical parameter meeting the preset condition, and otherwise controls itself to be turned off or maintains itself being off.

Abstract: The Disclosed in the present application are a power electronic device on a direct-current side of a photovoltaic system, and a test system and a control method therefor, achieving a simple, fast, and low-cost functional test on the power electronic device during a production process or a troubleshooting process of the power electronic device on the direct-current side of the photovoltaic system. The power electronic device is used for detecting a fluctuation of an electric signal parameter of an input end of the power electronic device; when the fluctuation meets a preset condition, the device is switched from a limited output state to a non-limited output state; the fluctuation of the electric signal parameter of the input end is generated by applying a disturbance to the input end of the power electronic device on the direct-current side of the photovoltaic system by a direct-current power supply having a disturbance output.

Abstract: A method for starting a photovoltaic rapid shutdown system, an application apparatus and a system are provided. In this method, the inverter system controls a voltage of a direct current bus in the photovoltaic rapid shutdown system. The photovoltaic module breaker makes determination based on a detected output voltage of the photovoltaic module breaker. In a case that the change characteristics of the voltage of the direct current bus connected to the photovoltaic module breaker meets the predetermined turn-on condition, the photovoltaic module breaker controls itself to be turned on. Therefore, the photovoltaic module breaker can determine whether the photovoltaic module breaker receives a turn-on signal only based on its own voltage acquisition device without an additional receiving apparatus.