A longitudinal island detection device

Abstract

The invention discloses a vertical island detection device, which includes a current control terminal, a grid-connected inverter, a voltage detection module, a data analysis unit, a passive detection module, a channel selection unit, a monitoring unit, a processor, a display unit, a storage unit, an alarm unit and a management unit; the present invention can switch the passive detection module at any time through the detection unit and the channel selection unit and use the data analysis unit to analyze whether the islanding effect occurs, avoiding the singleness of the traditional detection method. It is a relatively difficult problem; after obtaining the quantitative data corresponding to the island effect, and releasing the analysis of the quantitative data by the processor, it is possible to obtain the overall quality of the power supply network of the piece and whether the island effect of a single location is frequent, and aim at Frequent locations remind staff to pay attention to investigation.

Description

technical field [0001] The invention belongs to the field of island detection, and in particular relates to a vertically connected island detection device. Background technique [0002] With the global energy crisis and environmental problems becoming more and more serious, photovoltaic, wind power and other new energy power generation has developed rapidly in recent years. At present, the total installed capacity of photovoltaic power generation in China has reached about 47GW, and my country has become the country with the largest photovoltaic installed capacity in the world. Since isolated islands are likely to cause equipment damage, safety hazards to inspection personnel, and affect the reliable operation of new energy sources, the issue of photovoltaic grid-connected islands has received more and more attention. According to the relevant provisions of the island detection standard UL17417 and IEEE Stdl547, the distributed grid-connected power generation system must ha...

AI Technical Summary

Problems solved by technology

The passive method focuses on the electrical quantity changes at the grid-connected point caused by the mismatch between the output power of the photovoltaic system and the local load, including the over / under voltage method, over / under frequency method, phase jump method, and voltage harmonic detection method. Inject a disturbance signal, but there is a detection dead zone when the output of the photovoltaic power supply and the local load match a high degree

The active detection method injects a disturbance signal into the power grid and uses the electrical quantity change caused by the disturbance signal to judge the occurrence of islanding. Common methods include frequency shifting method, impedance measurement method, active / reactive power disturbance method, etc. These methods are effective Reduce the detection blind area, but it will affect the power quality

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