RU57051U1 - DC CIRCUIT BREAKER BY CONTACT SWITCHING MACHINE - Google Patents

Abstract

The utility model relates to electrical engineering and is intended to protect electrical equipment from short circuit currents and overloads. The device contains contacts, an arcing chamber, a parallel magnetic blast coil, an independent power source and a current sensor. The novelty of the device is that the device is equipped with a sequential magnetic blast coil, while an independent power source is configured to connect a parallel magnetic blast coil when the current flow in the circuit is less than the rated current of the DC disconnect device by a contact switching device, and with the ability to disconnect the parallel magnetic coil blast when current flows in a circuit equal to or greater than the rated current of this device. EFFECT: increased reliability of arc extinction between contacts when the device is turned off, due to arc extinction even with a faulty coil of a parallel magnetic blast or failure of an independent power source, as well as the exclusion of the value of the force acting on the arc is greater than that necessary for extinction arcs.

1 p. Fs

1 FIG. heck.

Description

The utility model relates to electrical engineering, namely to switching devices, in particular, to high-current devices, and is intended to turn off both high and low currents, for example, for switches protecting the electrical equipment of urban electric vehicles.

DC disconnecting devices are known, for example, from the following sources.

In the book, Taev I.S. Electrical control devices: A textbook for universities in the specialty "electrical devices". 2nd edition, revised. and add. - M .: Higher. shk., 1984., §3-2 describes a device that contains contacts included in the main circuit, an arcing chamber and a coil of parallel magnetic blast. A parallel magnetic blast coil is connected to a power source in the main circuit. The disadvantages of this device are: dependence on the direction of current flow in the main circuit, which does not allow to turn off the current when changing its direction; the absence of galvanic isolation between the contacts in the disconnected position of the contacts, which creates a risk of electric shock in operation; increased energy consumption due to the constant inclusion of parallel magnetic blasting coils in the main circuit.

These disadvantages are eliminated in the device according to the utility model of the Russian Federation No. 35923, H 01 H 33/62, 2005 (prototype).

It contains contacts included in the main circuit, an arcing chamber, a parallel magnetic blast coil, an independent power source to which a parallel magnetic blast coil is connected, and a current sensor for controlling an independent power source. Various current sensors can be used as current sensors, including those based on a Hall converter.

However, this device is not reliable enough to extinguish the arc at the time of shutdown. This is due to the possibility of failure of the coil of the parallel magnetic blast or a malfunction of an independent power source. A malfunction of the magnetic blast system during shutdown can lead to the ignition of the entire device, that is, to failure.

The patented utility model is aimed at increasing the life of the device and reducing the arc extinction time.

The technical result, which is achieved by the utility model, is to increase the reliability of the extinction of the arc between the contacts when the device is turned off.

This is achieved by the fact that the patented DC disconnect device is additionally equipped with a sequential magnetic blast coil connected in series with the contacts, while an independent power source has the ability to connect a coil

parallel magnetic blast when flowing through the contacts of the current is less than the rated current of the DC disconnect device by the contact switching device, and the ability to turn off the parallel magnetic blast coil when the current flows in the circuit is equal to or greater than the rated current of this device.

In the presence of the indicated coil of sequential magnetic blasting, the arc is extinguished even with a faulty coil of parallel magnetic blasting or the failure of an independent power source, which ensures the reliability of the patented device. At currents above the rated current flowing through the contacts of the device, the force acting on the arc during the flow of current through the coil of sequential magnetic blast is sufficient to extinguish the arc. In this case, when working together, the coil of parallel magnetic blast and the coil of sequential magnetic blast will create a force acting on the arc of a greater value than is required for extinguishing the arc. This can lead to the exit of the arc beyond the arcing device, which is an emergency situation, that is, there is a decrease in the reliability of the device. Therefore, it is essential to use an independent power source with the ability to connect a coil of parallel magnetic blast when current flows through the contacts less than the rated current of the DC disconnect device by a contact switching device, and with the ability to disconnect the parallel coil

magnetic blast when current flows through the contacts equal to or greater than the rated current of this device.

In addition, the specified connection (disconnection) of the parallel magnetic blast coil helps to reduce the power consumption of the patented device.

The patented device is illustrated by the drawing, where its figure shows a block diagram of the device.

The DC disconnecting device by the contact switching device contains contacts 1 included in the main circuit, an arcing chamber 2, a parallel magnetic blast coil 3, an independent power supply 4, a current sensor 5 for controlling an independent power source 4. An additional sequential magnetic blast coil 6 is connected in series with the contacts .

An electronic key is integrated in the circuit between the current sensor and the independent power source (shown in the drawing as a controlled contact in an independent power source).

Thanks to this electronic key, an independent power source can power the coil of parallel magnetic blast when the current flows through the contacts of a lower rated current of the device, and de-energize the coil of parallel magnetic blast when the current flows through the contacts of a current equal to or greater than the rated current of this device.

The current sensor controls both polarity and determines the magnitude of the current value. As a sensor in the developed device, a Hall converter is used. The power source 7 is designed to power an independent power source 4 and a current sensor 5. The independent power source can be performed on a capacitor bank or renewable chemical current sources, such as batteries. This source is capable of independently feeding a coil of parallel magnetic blast for the time necessary to extinguish the arc. As a power source 7 can be used low-voltage power supply network for domestic needs of electric vehicles. To ensure the minimum dimensions of the patented device, it is preferable that the current sensor is spatially arranged so that the magnetic field of the parallel magnetic blast coil creates a positive feedback between the current sensor and the parallel magnetic blast coil. A sequential magnetic blast coil is connected in series with contacts 1. The output of the current sensor of the current signal in the circuit is less than the nominal (<In) and connected to the same input of an independent power source. The direction of the current in the coil of the parallel magnetic blast is provided by the current sensor so that the force acting on the arc is directed towards the arcing chamber.

The device serves to disable the variable load 8.

The device operates as follows.

When the device is in operation, the sequential magnetic blast coil operates continuously.

According to the set current signal (Iust), contacts 1 open from the current sensor 5, the signal of the beginning of the opening of the contacts is fed to the "start" input of an independent power source. By the “Start” signal, a parallel magnetic blast coil 3 receives power with a polarity corresponding to the “current direction” signal from the current sensor 5. By the “current is less than the rated” signal (<In), the electronic key commutes the “Start” signal from the current sensor, providing power to the coil parallel magnetic blast only when the current in the circuit is less than the nominal. After the expiration of the time sufficient to extinguish the arc in the arcing device, the coil of the parallel magnetic blast is de-energized.

In the event of a failure of a parallel magnetic blast coil or an independent power source, arc extinction is ensured by a sequential magnetic blast coil.

This ensures the reliability of the DC disconnect device by a contact switching device.

Claims (1)

A DC disconnect device with a contact switching device comprising contacts included in the main circuit, an arcing chamber, a parallel magnetic blast coil, an independent power source and a current sensor, characterized in that the device is additionally equipped with a serial magnetic blast coil, while the independent power source is configured to connecting a parallel magnetic blast coil when the current flow in the circuit is less than the rated current of the DC disconnect device as a contact switching device, and with the ability to turn off a parallel magnetic blast coil when current flows in a circuit equal to or greater than the rated current of this device.