RU24324U1 - UNIVERSAL DEVICE FOR PROTECTING ELECTRIC RECEIVERS FROM HIGH VOLTAGE IN ELECTRICAL NETWORK - Google Patents

Abstract

1. A universal device for protecting electrical consumers from overvoltage in the power supply network, containing a semiconductor switch connected in series with the load and an output for connecting one power bus, a direct current source connected to one of its output with a threshold upper-level device and with a voltage divider, the output of which is connected to a threshold device of the upper level, the output of which is connected to a control circuit, which connected to the indicator by the way, characterized in that an electromagnetic relay is additionally introduced, the contacts of which are included in the circuit of a semiconductor switch made on two thyristors and a diode connected in parallel with each other, and the coil of the electromagnetic relay is connected to the output of the control circuit, which is connected to the indicator network is above normal, "and the DC source has an autonomous overvoltage protection element in the mains. 2. A universal device for protecting electrical consumers from high voltage in the power supply network according to claim 1, characterized in that an additional reed electromagnetic relay is introduced.

Description

UNIVERSAL DEVICE FOR PROTECTING ELECTRIC RECEIVERS FROM AN EXCESSIVE STRESS

IN ELECTRICAL NETWORK

The useful model relates to the field of electrical engineering, in particular, to methods of protecting the power supply of electrical appliances, radio equipment, including those with switching power supplies (IBN) from damage in case of emergency in a 220 V power supply network.

It is known Ustrostvo to protect electrical consumers from damage during voltage fluctuations in the mains, patent of Ukraine No. 21464 A, IPC N 02 N 3/20, publ. 04/30/98., Bull. No. 2, patent holders Koval V.I., Kulik M.A.

This device has a semiconductor switch, which is connected in series with the load and has an output for connecting to one power supply bus. In parallel with the mains voltage source, a direct current source is connected, which is connected with a high-level threshold device with one of its outputs, and a voltage divider with its output connected to a high-level threshold device, the output of which, in turn, is connected to a control circuit, which its output is connected to an indicator. In this device, the output of the control circuit is galvanically connected to the semiconductor switch and, in this case, when the load is shorted, the semiconductor switch fails. The control circuit and the threshold device of the upper level are energized and the protection device itself is practically not subject to recovery, that is, it has practically no reliability. In addition, the DC source itself is not sourced from high voltage in the mains and may fail in the same way as the protected device

IPC H 02 H 3/20

to protect the power receiver. The response time of the protection device is in accordance with the formula given in the description

T 1 + 0.5T 0.05 s.,

which is 2.5 periods of sinusoidal current and is critical for the protection of the UPS, for which it should be no more than 0.02 s., which narrows the scope of application of this protection device.

The utility model is based on the Universal device for protecting power receivers from increased voltage in the mains by setting an additional 11th introduction into the circuit of an electromagnetic relay whose contacts are included in the circuit of a semiconductor switch made on two thyristors and a diode connected in parallel with each other, and the coil of the electromagnetic relay is connected to the output of the control circuit, and the DC source has an autonomous method of protection against overvoltage in the mains, to ensure reliable protection of power consumers from overvoltage in the mains, including in devices with UPS; reliability of the protective device itself; expanding the range of technical methods for protecting electrical consumers.

The essence of the utility model is as follows. The following is known. The device has a semiconductor switch connected in series with the load, and has an output for connection to one power bus, in parallel with a power source, a DC source is connected, which is connected with one of its output to a threshold device of the upper level, and the second with a voltage divider, the output of which connected to a threshold device of the upper level, the output of which, in turn, is connected to a control circuit, which is connected to an indicator by its output. The following is new. An electromagnetic relay is additionally introduced into the device, the contacts of which are included in the circuit of the semiconductor switch.

performed on two thyristors and a diode connected in parallel with each other, and the coil of the electromagnetic relay is connected to the output of the control circuit, which is connected to the network indicator above the norm. The DC source has an autonomous overvoltage protection in the power supply network. The following is known. Semiconductor key, - Handbook of the amateur radio designer, edited by Chistyakova NI, “Energy, p. 466, table. 12.86. An autonomous method of protection is performed in the form of a ballast resistor connected in series with the primary winding of the transformer, Handbook of a radio amateur designer, edited by Chistyakova NI, “Energy, p. 318.

An additional reed electromagnetic relay is introduced into the circuit.

The technical result. The set of essential features of the proposed device allows, in the event of an increase in the voltage in the mains, long or short-term (pulsed), to protect the power receiver by disconnecting it from the power supply, or by switching the UPS of the power receiver to the power mode of one half-wave sinusoidal current of the power supply without disconnecting. The shutdown mode is intended for power consumers with transformer power supplies. The power mode of one half-wave sine wave. voltage is intended exclusively for UPSs, the input operating voltage range of which is 100 - 240 V. The ability to use a device to protect electrical appliances with different power supplies ensures its versatility. The control electrodes of the thyristors of the semiconductor switch are interconnected using an electromagnetic relay, the introduction of which into the protection device eliminates the galvanic connection of the threshold device of the upper level with a power supply circuit of 220 V, providing high

device reliability in the event of a short circuit in the load or just a breakdown of the thyristor. The power supply circuit of the device itself is protected from increased voltage by a ballast resistor, which ensures reliable operation of the device during overvoltage in the mode without disconnecting the load, that is, when working on a switching power supply. The use of a reed switch electromagnetic relay improves speed

protective device up to T 0.01 s., which guarantees the impossibility

high voltage supply to the protected power receiver. The device intentionally does not have a voltage limit in the direction of decreasing it, because when the voltage in the mains decreases, the power receiver may not turn on in operation, but it cannot fail instantly. Introduction to the device circuit of an autonomous means of protection of a direct current source ensures the operation of the protective device at a voltage in the mains up to 380 V.

The drawing shows: FIG. 1 is a block diagram of a device; figure 2 diagram of a semiconductor key.

The device has, Fig. 1, an alternating voltage source of pos. 1, a direct current source of pos. 2, a stand-alone protective device, pos. 3, divide voltage 11 pos. 4, a threshold level device pos. 3, a control circuit pos. 6, electromagnetic relay pos. 7, semiconductor switch pos. 8, load pos. 9, network indicator above the norm pos. 10, the network indicator pos. eleven.

The device operates as follows, FIG. 1. From the voltage source pos. 1, the alternating voltage is supplied through an independent means of protection pos.Z, made, for example, in the form of a ballast resistor, which is connected in series with the primary winding of the transformer, to the direct current source pos.2, from where the reduced and rectified voltage is supplied to the voltage divider pos.4.

From the voltage divider, the output voltage is supplied to the upper level threshold device, item 5, which switches when the voltage of the mains voltage is 250 V, reaching the control circuit item 6, the inhibit signal, and returns to its original position when the voltage decreases to 247 V, entering the control circuit resolving signal. At a normal voltage in the power supply network (220 V ± 10%), the enable signal from the threshold device of the upper level enters the control circuit. From the control circuit, the control signal is fed to the coil of the electromagnetic relay pos.7. The semiconductor switch pos. 8 is controlled by an electromagnetic relay, which allows switching the load pos. 9 in accordance with the signals at the output of the upper level threshold device. From a voltage source, an alternating voltage is supplied to the load through a semiconductor switch. The network indicator is higher than normal, pos. 10. When the threshold device of the upper level is triggered, the network indicator above the norm lights up. From a constant current source, a constant voltage is supplied to the network indicator, pos. 11. The semiconductor switch operates in two modes. Robot mode with off load. At normal voltage, figure 2, in the mains voltage is applied to the anode of thyristor D1 and to the cathode of thyristor D2. The control electrodes of both thyristors receive a control signal to open the electromagnetic relay through the icPi contacts from the mains voltage applied to D1 and D2, while the alternating current passes through the thyristors D1 and D2 to the load. When the voltage in the mains exceeds 250 V, the control signal does not arrive at the thyristors D1 and D2, since the contacts kP1 of the electromagnetic relay are in the open state, while the alternating current through the thyristors D1 and D2 does not pass to the load.

(2 / (f

at the same time, the contacts of the Si operating mode switch are open and the network indicator above the norm lights up. Operating mode without disconnecting the load. When powering electrical receivers with UPSs at normal voltage in the mains voltage is applied to the anode of thyristor D1 and to the cathode of thyristor D2. The control electrodes of both thyristors receive a control signal to open the electromagnetic relay through the icPi contacts from the mains voltage applied to D1 and D2, while the alternating current passes through the thyristors D1 and Dg to the load, and the diode Dz, which is connected through the closed contacts of the Si operating mode switch, is constantly open, that is, open thyristors bypass the diode Dz. When the voltage in the mains exceeds 250 V, the control signal does not enter the thyristors D1 and D2, since the contacts Pi of the electromagnetic relay are in the open state, while the alternating current through the thyristors D1 and D2 does not pass to the load, the network indicator above norms, and through the diode Dz, the alternating current passes only in one direction, passing one of the 11th wave of alternating current into the load. Thus, with increasing voltage in the mains, half of the effective value of the alternating current enters the load. This ensures the stable operation of the UPS of one full AC current, while the network indicator above the norm is on. 6

Applicants / Kharkhardin E.P. /

/ Kharkhardin A.E. /

Claims (2)

1. A universal device for protecting electrical consumers from overvoltage in the power supply network, containing a semiconductor switch connected in series with the load and an output for connecting one power bus, a direct current source connected to one of its output with a threshold upper-level device and with a voltage divider, the output of which is connected to a threshold device of the upper level, the output of which is connected to a control circuit, which connected to the indicator by the way, characterized in that an electromagnetic relay is additionally introduced, the contacts of which are included in the circuit of a semiconductor switch made on two thyristors and a diode connected in parallel with each other, and the coil of the electromagnetic relay is connected to the output of the control circuit, which is connected to the indicator network is higher than normal, "and the DC source has an autonomous overvoltage protection element in the mains. 2. A universal device for protecting electrical consumers from high voltage in the power supply network according to claim 1, characterized in that an additional reed electromagnetic relay is introduced.