Abstract: An MPPT control method and device, and a storage medium are provided. Power loss at the direct-current side of the photovoltaic inverter and conversion efficiency loss in an inverter circuit in the photovoltaic inverter affect efficiency of the photovoltaic inverter. The direct-current loss indicates power loss occurring at a direct-current side of the photovoltaic inverter. The conversion efficiency loss indicates power loss in the inverter circuit. The photovoltaic inverter is MPPT controlled based on the direct-current loss and/or the conversion efficiency loss. Therefore, the efficiency of the photovoltaic inverter can be improved based on the direct-current loss and/or the conversion efficiency loss, thereby increasing energy yield of the photovoltaic system.

Abstract: A power derating method for a photovoltaic tracking system, a controller and a photovoltaic tracking system are provided. A current operating power and a target derating power of a photovoltaic inverter are acquired. A total power derating amount is calculated based on the current operating power and the target derating power. A target power derating amount by a photovoltaic tracker is determined based on the total power derating amount and a preset derating amount distribution coefficient. A target tracking angle is determined based on the target power derating amount. The photovoltaic tracker is controlled to adjust a photovoltaic module to be at the target tracking angle and fix the photovoltaic module. The photovoltaic inverter is controlled to adjust a direct current operating voltage based on a difference between the total power derating amount and the target power derating amount.

Abstract: A method and apparatus for matching between photovoltaic devices, and a photovoltaic tracking system are disclosed. Identifiers of trackers, inverters and MPPT branches in a photovoltaic power station are acquired; a preset action instruction is sent to a target tracker, to instruct the target track to act in response to the preset action instruction; inverter data is obtained after sending the preset action instruction, and an identifier of a target MPPT branch of a target inverter that subjects to an expected MPPT branch change is determined; and the target tracker is mapped to the identifier of the target MPPT branch. The target tracker is determined arbitrarily from the trackers in the photovoltaic power station. Therefore, mapping between the trackers and the MPPT branches can be obtained by applying the method to all the trackers, which has a high matching efficiency and is less error-prone.

Abstract: The present invention provides a device for peening by coupling a laser shock wave and an ultrasonic shock wave in real time. The device includes a synchronization device, a laser device, two ultrasonic shock devices, a working platform and a control system. An upper casing is supported above a base through second hydraulic cylinders. Two supporting beams are provided under the upper casing through the second hydraulic cylinders. Limiting slide rails are provided under the upper casing through first hydraulic cylinders. The two ultrasonic shock devices are connected through the synchronization device, which is configured to synchronize movement and rotation of the two ultrasonic shock devices. The laser device is configured to generate a laser beam to pass through the upper casing and irradiate a surface of a workpiece. The control system controls the laser device to lag behind the two ultrasonic shock devices to perform laser shock.

Abstract: A power derating method for a photovoltaic tracking system, a controller and a photovoltaic tracking system are provided. A current operating power and a target derating power of a photovoltaic inverter are acquired. A total power derating amount is calculated based on the current operating power and the target derating power. A target power derating amount by a photovoltaic tracker is determined based on the total power derating amount and a preset derating amount distribution coefficient. A target tracking angle is determined based on the target power derating amount. The photovoltaic tracker is controlled to adjust a photovoltaic module to be at the target tracking angle and fix the photovoltaic module. The photovoltaic inverter is controlled to adjust a direct current operating voltage based on a difference between the total power derating amount and the target power derating amount.

Abstract: The present invention provides a device for peening by coupling a laser shock wave and an ultrasonic shock wave in real time. The device includes a synchronization device, a laser device, two ultrasonic shock devices, a working platform and a control system. An upper casing is supported above a base through second hydraulic cylinders. Two supporting beams are provided under the upper casing through the second hydraulic cylinders. Limiting slide rails are provided under the upper casing through first hydraulic cylinders. The two ultrasonic shock devices are connected through the synchronization device, which is configured to synchronize movement and rotation of the two ultrasonic shock devices. The laser device is configured to generate a laser beam to pass through the upper casing and irradiate a surface of a workpiece. The control system controls the laser device to lag behind the two ultrasonic shock devices to perform laser shock.

Abstract: Disclosed is a centralized MPPT exiting method for a photovoltaic inverter comprising multiple DC chopper circuits and one inverter circuit. The method comprises: when the photovoltaic inverter is in a centralized MPPT mode, MPPT control is implemented independently for each photovoltaic cell in a photovoltaic component and the maximum power point for each photovoltaic cell is obtained; a reference value of the maximum power point for each photovoltaic cell is determined according to the type of the multiple DC chopper circuits; whether the voltage difference between the other maximum power points and the reference value goes beyond an allowable voltage difference is judged and the operation of the DC chopper circuits connecting to the photovoltaic cells with a voltage difference beyond the allowable voltage difference is recovered.

Abstract: A DC-DC converter with a high transformer ratio includes two DC-DC converter bodies with inputs connected in parallel and outputs connected in series so as to ensure the high safe reliability and the high energy conversion efficiency of the DC-DC converter, while increase the boost ratio of the DC-DC converter.

Abstract: A DC-DC converter with a high transformer ratio includes two DC-DC converter bodies with inputs connected in parallel and outputs connected in series so as to ensure the high safe reliability and the high energy conversion efficiency of the DC-DC converter, while increase the boost ratio of the DC-DC converter.

Abstract: Disclosed is a centralized MPPT exiting method for a photovoltaic inverter comprising multiple DC chopper circuits and one inverter circuit. The method comprises: when the photovoltaic inverter is in a centralized MPPT mode, MPPT control is implemented independently for each photovoltaic cell in a photovoltaic component and the maximum power point for each photovoltaic cell is obtained; a reference value of the maximum power point for each photovoltaic cell is determined according to the type of the multiple DC chopper circuits; whether the voltage difference between the other maximum power points and the reference value goes beyond an allowable voltage difference is judged and the operation of the DC chopper circuits connecting to the photovoltaic cells with a voltage difference beyond the allowable voltage difference is recovered.

Abstract: A five level inverter comprises six switch tubes, two inductors, four capacitor units and two reverse current preventing devices. The common terminal of the third capacitor unit and the fourth capacitor unit is connected with the common terminal of the first capacitor unit and the second capacitor unit. The third capacitor unit and the fourth capacitor unit are used as the output filter circuit of the inverter, and the common terminal of the third capacitor unit and the fourth capacitor unit is used as the midpoint of the DC bus.

Abstract: A five level inverter comprises six switch tubes, two inductors, four capacitor units and two reverse current preventing devices. The common terminal of the third capacitor unit and the fourth capacitor unit is connected with the common terminal of the first capacitor unit and the second capacitor unit. The third capacitor unit and the fourth capacitor unit are used as the output filter circuit of the inverter, and the common terminal of the third capacitor unit and the fourth capacitor unit is used as the midpoint of the DC bus.