Safe Photovoltaic System

摘要

The invention relates to a photovoltaic system comprising at least one string of solar modules and a system for individually disconnecting the solar modules and for safely connecting or reconnecting the disconnected solar modules to the string. At least some of the solar junction boxes are “smart” and have a safety circuit that defines an operating state and a safe state. The solar junction boxes are switched from the safe state to the operating state, i.e. are activated, by injecting a starting current.

主权项

1. A photovoltaic system comprising at least one string of series-connected solar modules and adapted for individually disconnecting the solar modules and for safely connecting or reconnecting the disconnected solar modules to the string comprising:
a plurality of solar modules each one comprising a solar junction box, wherein said solar junction boxes each have input-side positive and negative connection elements connected to the voltage-carrying conductors of the positive and negative poles of the associated solar module, and each have positive and negative output-side connection elements;
wherein the solar modules are connected in series to form said string by means of a string line connected to said output-side positive and negative connection elements;wherein at least one of said solar junction boxes includes a safety circuit which comprises a short-circuiting switch between the output-side positive and negative connection elements and an isolating switch connected in series into the string, and which defines an operating state in which with the isolating switch closed and the short-circuiting switch open the solar power produced by the associated solar module is supplied from the solar junction box via the string line, and which defines a safe state in which with the isolating switch open and the short-circuiting switch closed the associated solar module is disconnected with respect to the string line by means of the safety circuit while the string line is nevertheless closed via the closed short-circuiting switch; a starter circuit connected to the string line and adapted to inject a starting current into the string line that is closed via the closed short-circuiting switch;
wherein the safety circuit includes a current sensor and is adapted to automatically switch from the safe state to the operating state in response to the starting current which flows through the string line that is closed by means of the short-circuiting switch and which is measured or detected by the current sensor.