Multi-DC (direct current) source input wiring detection system and photovoltaic group series-connected inverter system

Abstract

The invention discloses a multi-DC (direct current) source input wiring detection system for detecting the wiring situation between DC sources and access points. Each pair of DC source access points comprises anode and cathode access points; the wiring detection system comprises a gate circuit, a sampling circuit, a controller and a warning unit, wherein the gate circuit comprises a first electric switch and a second electric switch, and the first electric switch and the second electric switch are respectively connected with the anode and cathode access points in one-to-one correspondence; the controller is successively gated with the first electric switch and the second electric switch, only one first electric switch and one second electric switch can be gated every time, and the anode and cathode access points which correspond to the simultaneously gated electric switches are taken as the access points of different DC sources; the sampling circuit correspondingly samples voltage after the first electric switch and the second electric switch are gated to obtain corresponding sampled voltage; the controller outputs an abnormal detection result when the difference value between the sampled voltage and preset voltage is judged to exceed a preset range. The application can perform automatic detection without manual operation, so as to avoid personal safety accidents, save the labor cost and obtain accurate and reliable detection results.

Description

technical field [0001] The invention relates to the technical field of inverters, in particular to a multi-DC source input wiring detection system and a photovoltaic string inverter system. Background technique [0002] The photovoltaic panel in the photovoltaic string inverter system includes multiple photovoltaic strings, and the input of each photovoltaic string can be equivalent to a DC source. With the increase of stand-alone capacity, the way of multi-channel maximum power point tracking is generally adopted to expand the power generation. Usually, each channel of maximum power point tracking is generally composed of one or two circuits connected in series and parallel. As the number of strings connected to a single inverter increases, the possibility of wrong wiring during construction increases. There are hundreds of types of misconnection objectively, among which there are dozens of working conditions that seriously threaten the safety of inverters and components....

AI Technical Summary

Problems solved by technology

Such methods are simple in reason, but they are also accompanied by certain defects, and it is difficult to cover all scenarios

For example, using a multimeter to measure voltage is a heavy workload and poses a safety hazard to people. Secondly, when the external environment is harsh, the accuracy of manual detection results cannot be guaranteed.

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