SU415475A1 - DEVICE FOR CONTROL OF START-UP ELECTROTHERMAL INSTALLATION - Google Patents

Description

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The invention relates to the field of electrical engineering and can be applied to control the start-up of electrothermal installations: ki contact heating of the wire.

Devices are known for controlling the start-up of an electrothermal installation, for example, an electrical contact device, containing a controlled source of supply voltage, to the input terminals of which the output of the regulated current source and the capacitance are connected.

In order to improve the start-up conditions in the proposed device, a non-linear resistor is inserted between the input of the current source and one of the input Lemmas of the Nance source.

FIG. 1 shows a block diagram of the described device; in fig. 2 shows voltage variation curves at the output of the power supply source.

The block diagram of the device consists of a power supply source 1, a controlled current generator 2, a capacitance 3, a nonlinear resistor 4 and a switch 5.

Curve A is the optimal curve of control voltage, curve B is obtained when the prototype operates during start-up, and curve C is provided for the proposed devices.

The device works as follows.

When the key is connected to the generator of the current of the discharged capacitance, it begins to charge: it is pressed at a speed proportional to the initial output current of the generator. Since at low voltages x the value of the nonlinear resistor is large, the current is inverse

The connection varies slowly and its absolute value is small. Correspondingly, they vary slowly: the output current of the current generator 2, the rate of change of voltage on the capacitor 3, and the voltage of the output of the power supply 1.

As the voltage on the capacitor increases, the feedback current increases, and the latter increases faster than the capacitance on the capacitor, since the value of the nonlinear resistance of the resistor 4 decreases with increasing voltage. As a result, a rapid increase in the output current of the generator 2 begins, which determines the rate of rise (Voltage at capacitance 3. This voltage rise process continues until

until the current generator is in saturation mode, at which its current becomes paiBHbiM feedback current. From this point on, the voltage on the tank 5 and on the output of the source / supply does not change, which

corresponds to the end of the starting period.

Subject invention

A device for controlling the start-up of an electrothermal installation, for example, an electrocontact unit, containing a controlled supply voltage source, to whose input terminal 1M1 of which is regulated a HCTOHHHiKa current output and a capacitance, characterized in that, in order to improve starting conditions, between the current source input and from the input terminals of the voltage source a non-linear rezistor is switched on.

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