Abstract: A photovoltaic system and a communication method therefor. The communication method includes: each slave sends a report signal to a host, and monitors a response signal of the host; and if the at least one slave receives the response signal, the corresponding slave executes a corresponding action on the basis of the response signal. Therefore, communication between the host and each slave is achieved in a mode that each slave actively sends the report signal, the host is prevented from adopting a roll call query mode, and occupation of bus resources by the host is reduced.

Abstract: An IV curve scanning method and an IV curve scanning device for a multi-input converter are provided. For each of input converters in the multi-input converter, a starting scanning voltage, a starting scanning moment, and scanning voltages at respective target scanning points are so determined based on a preset starting voltage, a minimum voltage and a preset number of the target scanning points that at each of the target scanning points there is at least one of the input converters whose scanning voltage is greater than a target voltage. The IV curve scanning for the input converter is performed based on the starting scanning voltage, the starting scanning moment, and the scanning voltages at respective target scanning points.

Abstract: A control method applied to a relay circuit is provided. The relay circuit includes a controller, a relay, a controllable switch, and a power supply. The controllable switch is connected in series with a coil of the relay. The power supply is configured to supply power to the coil of the relay. The controllable switch is controlled by the controller. The method includes: receiving an operating parameter of the relay by the controller; and adjusting a driving force applied to the relay, based on the operating parameter by the controller, to reduce a sum of a conduction loss and a driving loss of the relay, thereby improving the efficiency of the relay.

Abstract: A photovoltaic tracking method and apparatus, a tracking controller and a photovoltaic tracking system. The method includes: determining an advance adjustment time instant between a previous preset adjustment time instant and a next preset adjustment time instant; obtaining a target tracking angle of a tracking bracket corresponding to the next preset adjustment time instant; and adjusting an angle of the tracking bracket to the target tracking angle in a case that a current time instant is the advance adjustment time instant, wherein the angle of the tracking bracket remains unadjusted at the previous preset adjustment time instant and the next preset adjustment time instant. In this application, the power generation of the photovoltaic module is increased in the time period from the previous preset adjustment time instant to the next preset adjustment time instant, thereby reducing the power loss of the photovoltaic power generation.

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 for component voltage limitation, and an apparatus and a system for applying the same. At least one photovoltaic cell in a photovoltaic-cell string is controlled to operate in a voltage-limited mode, in response to receiving an instruction for enabling voltage limitation. Thereby, the voltage of the photovoltaic-cell string is reduced. A quantity of photovoltaic modules connected in series can be increased, while a highest voltage of the system is guaranteed not to exceed a corresponding requirement. A system cost is reduced. The photovoltaic cell operating in the voltage-limited mode is controlled to resume a normal output, in response to receiving the instruction for suspending voltage limitation. The output voltage of the photovoltaic-cell string is increased. Thereby, a rate of utilization on a direct voltage, and a PVIR of DC/AC are improved for the photovoltaic system.

Abstract: Provided are a device for suppressing potential induced degradation and a system. The device includes a rectification circuit, a non-isolated voltage conversion circuit and at least one capacitor. An input terminal of the rectification circuit is connected to an output terminal of a converter, the rectification circuit is configured to rectify an alternating current outputted by the converter into a direct current, the non-isolated voltage conversion circuit is configured to perform voltage conversion on the direct current outputted by the rectification circuit, and the voltage conversion is boost conversion or voltage reverse conversion. The capacitor is connected in parallel with an output terminal of the direct current, and either a positive electrode or a negative electrode of the capacitor is grounded.

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: A photovoltaic system and a method for determining a combiner box set for the photovoltaic system are provided. The photovoltaic system includes a photovoltaic array divided into at least two combination groups, a photovoltaic converter, and a combiner box in at least one nonfinal stage and a combiner box in a final stage for each of the at least two combination groups. A direct current side of the photovoltaic converter is electrically connected to an output terminal of the combiner box in the final stage. The combiner box in the final stage and the combiner box in the at least one nonfinal stage are configured to combine outputs of photovoltaic strings in the combination group. Each combiner box combines multiple cables into a single cable.

Abstract: A circuit for modulating a control signal, an inverter and a system for controlling a photovoltaic string. The circuit is based on a DC/DC boost circuit. The DC/DC boost circuit includes a controllable switch circuit, via which a second capacitor charges a first capacitor in the DC/DC boost circuit. A switch state of a first controllable switch in the DC/DC boost circuit is controlled when a voltage of the first capacitor is greater than or equal to a first voltage threshold, so that the first capacitor generates a control signal with a predetermined characteristic waveform.

Abstract: After a first device logs in to a first account in a first application, the first receives a first operation performed by a user on the first application. Login information of the first account includes the first account, or the first account and a login password of the first account. The first device displays, in response to the first operation, a first interface including one or more device options. Each device option corresponds to one wireless device found by the first device. The first device sends, in response to a selection operation performed by the user on a first device option on the first interface, identity information of the first application and the login information of the first account to a second device corresponding to the first device option.

Abstract: A photovoltaic system and a communication method therefor. The communication method includes: each slave sends a report signal to a host, and monitors a response signal of the host; and if the at least one slave receives the response signal, the corresponding slave executes a corresponding action on the basis of the response signal. Therefore, communication between the host and each slave is achieved in a mode that each slave actively sends the report signal, the host is prevented from adopting a roll call query mode, and occupation of bus resources by the host is reduced.

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: Embodiments relate to a permission management method and system. The method includes: receiving a first request sent by a controlled device. The first request includes a device identifier of the controlled device and indication information of a target operation; detecting a network status of a controlling device associated with the controlled device, where when the controlling device is in different network statuses, one or more controlled devices have different permission for performing respective operations; determining, based on the network status of the controlling device, the device identifier of the controlled device, and the indication information of the target operation, permission for performing the target operation by the controlled device; and processing the first request based on the determined permission for performing the target operation by the controlled device.

Abstract: An active bypass control device and an active bypass control method for a photovoltaic module are provided. The device includes a power source, a sampling unit, a controller, N first driving circuits, and N first controllable switches. Each first controllable switch is connected between one pair of bypass ports and includes a first switch and a first diode that are antiparallel. The first diode is reversely connected between the pair of bypass ports, and a control end of the first switch is connected to the controller via the corresponding first driving circuit. Based on a sampling signal provided by the sampling unit, the controller determines whether analog quantity information of the first controllable switch meets a predetermined bypass condition. If the predetermined bypass condition is met, the first switch is controlled to be turned on by using the first driving circuit.

Abstract: A circuit for modulating a control signal, an inverter and a system for controlling a photovoltaic string. The circuit is based on a DC/DC boost circuit. The DC/DC boost circuit includes a controllable switch circuit, via which a second capacitor charges a first capacitor in the DC/DC boost circuit. A switch state of a first controllable switch in the DC/DC boost circuit is controlled when a voltage of the first capacitor is greater than or equal to a first voltage threshold, so that the first capacitor generates a control signal with a predetermined characteristic waveform.

Abstract: A shutdown control system and a shutdown control method are provided. A main circuit is a series circuit formed by connecting output ends of multiple shutdown circuits in series or a series-parallel circuit formed by connecting output ends of multiple such series circuits in parallel. Each of the multiple shutdown circuits is connected to at least one of direct current power supplies in a distributed power generation system. A control circuit includes a SCU, one or more ACUs, and multiple PCUs corresponding to the multiple shutdown circuits. The SCU and the ACU are configured to transmit respective mode control instructions when respective condition is satisfied. Each of the multiple PCUs is configured to obtain multiple criteria based on the mode control instructions, determine a target operation mode of a corresponding shutdown circuit, and control the shutdown circuit to operate in the target operation mode.

Abstract: A circuit for component voltage limitation and an apparatus for applying the same. A detection-and-control unit detects a parameter of a photovoltaic-cell string, and controls operation of a switch unit according to the parameter. In a case that the switch unit controls at least one photovoltaic cell connected to the switch unit to operate in a voltage-limited mode according to control of the detection-and-control unit, a voltage of the photovoltaic-cell string can be reduced. In a case that that the switch unit controls a photovoltaic cell operating in a voltage-limited mode to resume a normal output according to control of the detection-and-control unit, an output voltage of the photovoltaic-cell string can be increased. The rate of utilization on the direct voltage and the PVIR of DC/AC are improved for the photovoltaic system.

Abstract: A circuit for component voltage limitation and an apparatus for applying the same. A detection-and-control unit detects a parameter of a photovoltaic-cell string, and controls operation of a switch unit according to the parameter. In a case that the switch unit controls at least one photovoltaic cell connected to the switch unit to operate in a voltage-limited mode according to control of the detection-and-control unit, a voltage of the photovoltaic-cell string can be reduced. In a case that that the switch unit controls a photovoltaic cell operating in a voltage-limited mode to resume a normal output according to control of the detection-and-control unit, an output voltage of the photovoltaic-cell string can be increased. The rate of utilization on the direct voltage and the PVIR of DC/AC are improved for the photovoltaic system.

Abstract: A method for component voltage limitation, and an apparatus and a system for applying the same. At least one photovoltaic cell in a photovoltaic-cell string is controlled to operate in a voltage-limited mode, in response to receiving an instruction for enabling voltage limitation. Thereby, the voltage of the photovoltaic-cell string is reduced. A quantity of photovoltaic modules connected in series can be increased, while a highest voltage of the system is guaranteed not to exceed a corresponding requirement. A system cost is reduced. The photovoltaic cell operating in the voltage-limited mode is controlled to resume a normal output, in response to receiving the instruction for suspending voltage limitation. The output voltage of the photovoltaic-cell string is increased. Thereby, a rate of utilization on a direct voltage, and a PVIR of DC/AC are improved for the photovoltaic system.