DE102010032978A1 - Electrical safety system for inspection of solar system in roof of building, has safety mechanisms and switches for interrupting supply of current to solar panels such that solar panels have small inherent voltage and current - Google Patents

Abstract

The electrical safety system has safety mechanisms and separate switches for interrupting the supply of current to each solar panels through solar cables. The supply of power to the solar system is stopped using the safety mechanisms and switches, such that the solar panels have small inherent voltage and current. The solar panels are set in similar state without the possibility of energy and/or power distribution.

Description

State of the art:

Sometimes, with solar systems, only the inverter as a consumer is disconnected from the power grid of the system with an emergency switch. The system is thus without consumers but is under very high voltage.

Problem:

On inspection of the plant or use of the fire brigade z. B. in case of fire may be due to damaged connections in the power network of the system in contact people or extinguishing agents (liquids or surfaces covering substances) prove to be conductive and allow people to act as a consumer. This would mean that the currents flow and the very high applied voltages (up to 1000 V) act unchecked on these persons until death.

Achieved advantages / solution:

The advantage of this invention is the area of the system at any time before access to the site or in emergency operations voltage or electricity and thus persons who enter this system targeted, no risk of lines with high voltages or the like come in or possible Total currents can be switched off. This fully targeted shutdown of voltage and current is independent of size, power or location of the plant. A defined access or switch in the access area turns the system, which is otherwise occupied by high voltages and currents, into a safe and freely accessible open space.

The solution is, in addition to the manual shutdown of mostly decentralized inverters, an additional electrical emergency stop system, which is directly on the solar panels and is under constant tension. In case of faults or interruptions immediately and completely interrupts a possible energy or power supply from the origin ago and thus the system in any case independently on all cables of the entire area voltage-free and thus safe. This type of plant protection is already marketable and represents the missing link between use and safety in solar technology.

On each panel, an optocoupler / switch is mounted between the junction box and the solar panels of the panel. This switch is powered by a separate circuit (A). The switches are permanently energized. If there is a current drop in the circuit, the switch will switch off and interrupt the supply of the solar panel to the solar cable and thus to the solar network (B) of the solar system.

The interruption takes place on the back of the panel. The power supply to circuit A is located in the building or is supplied by the solar power B. A current drop of the circuits A can be caused by all events. In addition, there is an emergency switch (contactor) in the building for the manual interruption of circuit A and thus for the complete shutdown of the solar system.

The access to the system (access door) additionally leads to a contact, which interrupts circuit A when the access door is opened, thus disconnecting the entire system from the power and current. At the same time, the emergency switch in the building is activated. This can only be unlocked manually if the access door is closed at the same time.

For maintenance work by qualified personnel, each individual string (baying of panels) on the optocouplers / switches can be switched on and off via another device. This is on the access door z. B. Interlog switch. After opening the access door, the Interlog switch must be operated manually and the emergency switch in the building must also be unlocked. Afterwards, the specialist personnel can switch the tension of the strings on and off individually via separately mounted locking switches with turnstile. The locking switches can only be accessed via a fuse box to be blocked off.

The triggering of the safety system for voltage and current-free system can thus be done in three different ways. 1. In the building at the emergency switch. 2. By opening the access door to the system and 3. By switching off all strings at the fuse box of the system. These options are available above all to the fire brigade in order to ensure access to a voltage- and current-free solar system from all directions in the event of a fire in the system. The system thus does not respond to any possible consumers (humans) or conductive materials (eg water).

Application:

The application mainly takes place in the field of solar technology at plants for energy production. This can be applied both on open spaces and on roofs. For new plants as well as in the retrofitting of existing plants. Plant safety represents a considerable part of plants in solar technology.

Claims (1)

For an electrical safety system for safe commissioning of solar systems under the conditions of complete voltage and current freedom of the system from the solar panels by separating all the individual solar panels from the power supply in all cables of the solar system, characterized in that by security mechanisms and separate switch the power supply of each Solar panels to the solar cable is interrupted. The system is thus in tension and current free as the isolated panels with low residual stress and ampere is no hazard to persons. The panels are then in a similar state of outdoor storage without the possibility of power distribution.

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