RU212728U1 - Ionistor protection device against impulse switching overvoltage and supply voltage dips - Google Patents

Abstract

The utility model relates to the field of electrical engineering, namely to devices for protecting electronic equipment from supply voltage deviations, and is intended to improve the reliability of the operation of electronic equipment by protecting it from the effects of impulse switching overvoltages (ICP) and voltage dips that occur in DC power supply networks at normal and emergency switching of powerful equipment. The purpose of the utility model is to ensure the constancy and continuity of the power supply of the protected equipment in the event of an ICP and voltage dips. The device contains an input diode, the first and second voltage divider resistors, a shunt capacitor, a bias resistor, a protective switch transistor suppressor, a switch high-voltage p-channel field-effect transistor with an inductive channel, an auxiliary high-voltage n-channel field-effect transistor with a built-in channel, a protective auxiliary transistor suppressor, damper diode, output suppressor, output LC filter, charging resistor, diode, ionistor module. New is the use of the first and second voltage divider resistor, shunt capacitor, bias resistor, suppressor of the protective key transistor, key high-voltage p-channel field effect transistor with an induced channel, auxiliary a high-voltage n-channel field effect transistor with a built-in channel, a suppressor of a protective auxiliary transistor, a damper diode, an output suppressor, a charging resistor, a diode, an ionistor module.

Description

The utility model relates to the field of electrical engineering, namely to devices for protecting electronic equipment from supply voltage deviations, and is intended to improve the reliability of the operation of electronic equipment by protecting it from the effects of impulse switching overvoltages (ICP) and voltage dips that occur in DC power supply networks at normal and emergency switching of powerful equipment.

A known method of protection against surges [Patent No. 2264015 C1, pub. - 10.11.2005. - Bull. No. 31], in which protection against impulses of switching and induced overvoltages, as well as limitation of inrush currents when the supply voltage is turned on and its abrupt increase is carried out during the action of the impulse due to periodic switching of the load supply circuit with a proximity switch and voltage smoothing using an LC filter. The contactless key is controlled depending on the voltage on the inductor and the rate of change of voltage on the capacitor.

The disadvantages of the method:

- the need for devices for tracking interference and controlling high-frequency switching of the key, as well as for providing a protected power supply for such devices;

- high-frequency switching interferes with the input network;

- does not provide compensation for voltage dips.

Known filter switching overvoltages in the DC network [Patent No. 61480 U1; pub - 02/27/2007], at the input of which the radio interference filter reduces the level of interference into the input network during high-frequency switching of power elements in the device and the load. The control unit with a two-level comparator and a delay circuit controls the input voltage and current from the current sensor and, after the end of the input voltage transients, starts the key driver. The key driver switches the transistor key with high-frequency pulses with a variable duty cycle to maintain a constant current. The parameters of the inductor, protective diode and capacitor are chosen so that short microsecond noise is satisfactorily suppressed.

When exposed to long-term pulses of the millisecond range, the driver closes the transistor switch, and the entire interference voltage is applied to the high-voltage transistor switch. A varistor is connected in parallel to the transistor key, which protects the key from breakdown.

The disadvantages of the known device are:

- the power supply of the control unit and the driver comes from an unprotected network and is affected by the ICP;

- does not provide uninterrupted power supply with long pulses;

- does not provide power in case of voltage dips in the network.

Closest to the claimed solution can be attributed to the device protection against switching surges [Patent No. 2309534 C1, pub. - 27.10.2007.- Bull. No. 30], containing a powerful high-voltage electronic key in the form of an IGBT module with a discharge diode, a current sensor, an output LC filter, a module control device (UUM) and a voltage control device (UKN), one input of which is connected to the input positive terminal and the first to the input of the electronic key, and the second one to the output positive terminal and the output of the LC filter, the output of the UKN is connected to the first input of the CCM, the signal from the output of the current sensor is fed to the second input of the CCM, the output of the CCM is connected to the control input of the electronic key, the output of the electronic key is connected to the input current sensor, the output of the current sensor is connected to the first input of the LC filter, and the second input of the LC filter is connected to the input and output negative terminals, as well as to the second input of the electronic switch.

The disadvantages of the known device include the need for a powerful high-voltage switch with a heat sink to ensure the linear operation of the circuit. In addition, the circuit does not provide compensation for supply voltage dips.

Thus, the purpose of the utility model is to ensure the constancy and continuity of the power supply to the protected equipment in the event of an ICP and power supply voltage failures.

This goal is achieved by the fact that the input diode, the first and second voltage divider resistors, a shunt capacitor, a bias resistor, a protective key transistor suppressor, a key high-voltage p-channel field transistor with an induced channel, an auxiliary high-voltage n-channel field-effect transistor with a built-in channel, a protective suppressor of the auxiliary transistor, a damper diode, an output suppressor, a charging resistor, a diode, an ionistor module, the positive output of which is connected to the anode of the diode, and the charging resistor is connected to the output through a resistor the positive terminal, the diode cathode, the first terminal of the filter capacitor and the second terminal of the filter inductor, the first terminal of the filter inductor is connected to the drain of the key high-voltage p-channel field effect transistor, the cathode of the damper diode and the cathode of the output suppressor, the anode of which is connected to the output negative terminal, minus terminal of the ionistor module, the second terminal of the filter capacitor, the anode of the damper diode, the gate of the auxiliary high-voltage n-channel field-effect transistor, the anode of the suppressor of the protective auxiliary transistor, the negative input terminal, the first terminal of the second resistor of the voltage divider, the second terminal of the second resistor of the divider is connected to the cathode of the suppressor of the protective auxiliary transistor, the source of the auxiliary field-effect transistor, with the first terminal of the shunt capacitor, the first terminal of the first voltage divider resistor, the second terminal of which is connected to the source of the key field-effect transistor, the suppressor cathode of the protective key transistor, the second terminal of the shunt capacitor, the cathode of the input diode, the first terminal of the bias resistor , the second output of which is connected to the suppressor anode of the protective key transistor, to the gate of the key field-effect transistor and to the drain of the auxiliary field-effect transistor, the anode of the input diode is connected inen with a positive input terminal.

In FIG. 1 shows an electrical circuit diagram of an ionistor protection device against IKP and supply voltage failures.

The ionistor protection device against IKP and supply voltage dips contains an input diode 3, an input voltage divider on resistors 4 and 5, a shunt capacitor 6, a bias resistor 7, a suppressor protective key transistor 8, a high-voltage auxiliary n-channel field-effect transistor with a built-in channel 9, a suppressor protective auxiliary transistor 10, key high-voltage p-channel field-effect transistor 11, damper diode 12, output suppressor 13, inductor 14, capacitor 15, charging resistor 16, diode 17, ionistor module 18.

The device works as follows.

The rated mains or onboard input DC supply voltage (Ivkh) is supplied to input contacts 1 and 2. Through a series-connected input diode 3, it enters the source of the key high-voltage p-channel field-effect transistor with an induced channel 11, and through resistor 7 to its gate. The auxiliary high-voltage n-channel field-effect transistor with a built-in channel 9 is open, since the division ratio of the resistive divider on resistors 4 and 5 is chosen in such a way that, in the absence of ICP pulses, the voltage between the gate and source of the auxiliary transistor 9 is less than the cutoff voltage. Therefore, a current flows through resistor 7, auxiliary transistor 9 and resistor 5, creating a voltage drop across resistor 7. As a result, a negative potential is formed at the gate of the key transistor 11 relative to its source and the key transistor 11 is open. Further, the input voltage through a low-frequency filter from the choke 14 and capacitor 15 is applied to the output contacts 19 and 20 to power the load, while the ionistor module 18 is charged through the charging resistor 16.

When an ICP appears at the input terminals 1 and 2, the voltage at the output of the resistive divider across resistors 4 and 5 increases, the voltage between the source and gate of the auxiliary transistor 9 exceeds the cutoff voltage, and the auxiliary transistor 9 is turned off. As a result, the voltage between the gate and the source of the key transistor 11 will approach zero, and the key transistor 11 will close, cutting off the load from the overvoltage pulse. At the same time, the load will be powered from the ionistor module 18 through the diode 17, bypassing the charging resistor 16. The capacity of the ionistor module 18 is determined by the maximum load supply time, the maximum load current and the allowable voltage drop across the ionistor module 18 during discharge. The low-capacity high-voltage shunt capacitor 6 is designed to speed up the turn-off of the auxiliary transistor 9, while the suppressor 10 limits the voltage between the gate and source of the auxiliary transistor 9. The suppressor 8 protects the switching transistor 11 from overvoltage between the gate and source when the operation of the auxiliary transistor 9 is delayed. Low-frequency LC- a filter consisting of a choke 14 and a capacitor 15 serves to smooth out microsecond pulses that appear at the output as a result of the delay in the operation of the auxiliary transistor 9 and the switching transistor 11. The damper diode 12 eliminates negative voltage surges. Suppressor 13 additionally serves to protect the load and ionistor module 18 from microsecond pulses that enter the output during the turn-off delay of the switching transistor 11.

When supply voltage dips occur at terminals 1 and 2, the voltage at terminals 19 and 20 becomes lower than the value on the ionistor module 18, and the load is powered from the ionistor module 18 through diode 17. Input diode 3 prevents the ionistor module from discharging through the mains source, as well as protects the device circuitry from reversing the polarity of the input signal.

Thus, unlike the known ones, the proposed ionistor protection device against ICP and supply voltage dips due to the use of an ionistor module makes it possible to avoid the use of powerful transistor switches for the implementation of relay or linear modes of stabilization of the ICP. At the same time, the device provides protection not only from short-term (of the order of fractions of microseconds) and long-term (up to a few seconds) ICP, but also from voltage dips of similar durations. The duration of operation in the protection mode against IKP and supply voltage dips is determined by the capacitance and operating currents of charging and discharging the ionistor module and the power consumption of the load.

Claims (1)

An ionistor protection device against switching surges and supply voltage dips, containing an output LC filter, characterized in that an input diode, the first and second voltage divider resistors, a shunt capacitor, a bias resistor, a protective key transistor suppressor, a key high-voltage p-channel field transistor with an induced channel, an auxiliary high-voltage n-channel field-effect transistor with a built-in channel, a protective suppressor of the auxiliary transistor, a damper diode, an output suppressor, a charging resistor, a diode, an ionistor module, the positive output of which is connected to the anode of the diode, and the charging resistor is connected to the output through a resistor the positive terminal, the diode cathode, the first terminal of the filter capacitor and the second terminal of the filter inductor, the first terminal of the filter inductor is connected to the drain of a key high-voltage p-channel field effect transistor, the cathode of the damper diode and the cathode of the output suppressor, the anode of which is connected with output minus terminal, minus terminal of ionistor module, second terminal of filter capacitor, damper diode anode, gate of auxiliary high-voltage n-channel field-effect transistor, suppressor anode of protective auxiliary transistor, negative input terminal, first terminal of second voltage divider resistor, second terminal of second divider resistor connected to the suppressor cathode of the protective auxiliary transistor, the source of the auxiliary field-effect transistor, the first terminal of the shunt capacitor, the first terminal of the first resistor of the voltage divider, the second terminal of which is connected to the source of the switching field effect transistor, the suppressor cathode of the protective switching transistor, the second terminal of the shunt capacitor, the cathode of the input diode , the first output of the bias resistor, the second output of which is connected to the suppressor anode of the protective key transistor, to the gate of the key field-effect transistor and to the drain of the auxiliary field-effect transistor torus, the anode of the input diode is connected to the positive input terminal.

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