RU2290737C1 - Method for controlling semiconductor switch - Google Patents

Abstract

FIELD: semiconductor engineering; generating pulsed or continuous-wave control signal by semiconductor switch isolated from input control circuit.

SUBSTANCE: proposed method includes conversion of input-section supply voltage into current pulses through input section of coupling transformer, current pulse amplitude being limited by controlling pulse length and repetition rate, as well as discrimination of semiconductor-switch sawtooth control signal across coupling-transformer output section. To this end rise time of current pulse amplitude is set through output section of coupling transformer to desired level not to exceed critical value and in order to turn on or off semiconductor switch or to maintain it in on- or off-position voltage discriminated in one direction is checked upon expiration of desired time interval counted from moment of first threshold level of voltage across coupling transformer output section for its rising above second threshold level, first threshold voltage being set not to exceed threshold voltage of semiconductor switch and second threshold voltage, to be higher than minimal permissible control voltage for semiconductor switch; check results are used to regulate voltage in one direction discriminated across coupling-transformer output section in semiconductor switch control circuit.

EFFECT: enhanced reliability and stability of semiconductor switch control characteristics.

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Description

The technical field to which the invention relates.

The invention relates to a semiconductor technology and is intended to generate a pulsed or continuous control signal of a semiconductor key, isolated from the input control circuit.

The level of technology.

A device is known in which the transmission of a control signal and energy for generating a control signal of a semiconductor key is provided through a single galvanic isolation element - a communication transformer. The device comprises an input converter, a communication transformer, a field-effect transistor detector.

A device implemented on the basis of the proposed method provides the possibility of a significant increase in insulation voltage. The device does not require an additional isolated power source in the control circuit of the semiconductor key, which gives significant advantages over similar systems using such power sources (INTERNATIONAL RECTIFAIER catalog, 2003, P.WOOD, AN-950, article “MOSFET driver with transformer isolation provides high values of duty cycle ").

The disadvantage of the control method: low electromagnetic stability when the power switch is off, and the inability to generate control signals of long duration.

Known methods of encoding and decoding information in order to transmit and reproduce an isolated digital signal.

The input signal passes through a circuit that differentiates the edges of the input signal and controls the input coils of the corresponding transformer with “set high” or “set low” signals. The output coils of the respective transformers restore the “set high” or “set low” signals. The receiver circuit restores the original waveform, while the internal polling circuit analyzes the input signal at a predetermined frequency and transmits its own signal to "set high level" or "set low level" in case of a device failure. The system recovery time is determined by the period of operation of the internal polling scheme.

Electromagnetic stability is ensured by shunting additional transformer input coils at specified time intervals according to the logic of the circuit and due to the relatively high level of the transition signals “set high” or “set low”, the operation of the internal interrogation circuit and analysis of the result of the signal circuit through the isolation barrier ( US Pat. ACR OSS AN ISOLATION BARRIER).

The methods of isolating the control signal described above require the presence of isolated power sources at the input and output and two transformers each to transmit the corresponding logical levels.

The closest in technical essence and the achieved positive effect and adopted by the author for the prototype is a control method implemented by a semiconductor device containing an active current limiter based on an analog-pulse converter, an insulating communication element and a semiconductor key. The method implemented in this device provides, by limiting the duration of the pulses through the input section of the communication element and changing their repetition rate, limiting the amplitude of the current pulses at an adjustable threshold element level (RF Patent for the invention No. 2206147 of 06/10/2003, "Input device of a semiconductor key ").

The disadvantage of the control method implemented in this device is the limited resistance to external electromagnetic fields for the communication element based on the electromagnetic effect, provided only by amplitude or frequency filtering of the converted signal in the control circuit of the semiconductor key, as well as the possibility of incomplete switching on or off of the semiconductor key.

Disclosure of the invention.

The goal that can be achieved using the present invention is to increase the reliability and stability of the control characteristics of the semiconductor key.

The technical result is achieved by the fact that in the proposed method for controlling a semiconductor switch, which consists in converting the supply voltage of the input section to current pulses through the input section of the communication transformer with limiting the amplitude of the current pulses and changing their repetition rate, and isolating a semiconductor control signal convert to the output section of the transformer key, unlike analogs and prototypes, set the rise time of the amplitude of the current pulses through the input section of the transformer ligature to the set level amplitudes with a duration not exceeding the critical value. To turn the semiconductor switch on or off, or to keep it on or off, the first threshold level is monitored after the specified time interval and counts from the moment the voltage reaches one direction allocated from the output section of the communication transformer, the fact that the selected voltage exceeds one second direction exceeds the second threshold level level. In this case, the first threshold level is set to not exceed the intrinsic threshold voltage of the semiconductor key, and the second threshold level is set to exceed the intrinsic minimum allowable control voltage of the semiconductor key. According to the results of the control, the voltage of one direction isolated from the output section of the communication transformer in the control circuit of the semiconductor switch is regulated.

A brief description of the drawings.

Figure 1 shows an example of solving a functional diagram of a semiconductor device that implements the invention.

Figure 2 shows a timing diagram of the signals explaining the operation of the active current limiter 5 of the input section.

Figure 3 shows the timing diagrams of the signals in the main nodes of the device based on the functional diagram of figure 1 when modulating and demodulating the input control signal 26 and the formation of a convert control signal 33.

Figure 4 shows a timing diagram of the signals explaining the operation of the transducer waveforms of control 12 at a low slew rate of voltage across the capacitance 14.

Figure 5 shows the timing diagrams of the signals explaining the operation of the transducer waveforms of control 12 at a high slew rate of voltage across the capacitance 14.

Figure 6 shows the timing diagram of the voltage 30 on the capacitance 14 and the convert control signal 33 for the voltage level 25 of the input section 5, insufficient to turn on the semiconductor switch 22.

Figure 7 shows the timing diagrams of the control signals 26 on the capacitance 14 and the convert control signal 33 in conditions of high-frequency electromagnetic interference.

On Fig given an example of a solution to the functional block circuit analysis 16 of a semiconductor device that implements the invention.

Figure 9 shows an example of the inclusion of a semiconductor switch 22 for controlling the thyristor 41.

The implementation of the invention.

Examples of specific embodiments of a semiconductor key control method.

Example 1. The input logical signal is converted into a sequence of current pulses through the input section of the communication transformer with a limited minimum repetition rate using an active current limiter that provides analog-to-pulse conversion of the logical signal. The amplitude of the current pulses is continuously compared with the set level of the current amplitude limitation, while the current amplitude limitation level and the pulse frequency are changed in accordance with a predetermined dependence on the supply voltage of the input section. If the current amplitude limit is exceeded, the current pulse is interrupted for a time determined by the pulse repetition period. This limits the energy spent on conversion, and guarantees the operation of the communication transformer in a given hysteresis cycle in a wide range of changes in the supply voltage and characteristics of the communication transformer itself. The converted signal is removed from the output section and rectified, with the help of a capacitive filter, its constant component is extracted, which is subjected to amplitude filtering. All these transformations, controlled by the input logical signal, give advantages, since as a result of all the above actions, the voltage of one direction is supplied to the control circuit of the semiconductor key, unlimited by the characteristics of the communication transformer of duration and exceeding the minimum allowable control voltage of the semiconductor key. If the amplitude of the convert control signal is not sufficient for the semiconductor switch to fully turn on, then the voltage that does not exceed the threshold voltage of the semiconductor switch, determined by the level of amplitude filtering, is set in the control circuit of the semiconductor switch. If the semiconductor key is in the off state, the logic signal at the input corresponds to the state “off”, and the semiconductor key is affected by a transient voltage with a high slew rate, then a noise switching voltage is generated in the control circuit of the semiconductor key, which, starting from a certain level, will suppressed by an amplitude filter.

The described control method has advantages over analogues and prototype, provides the ability to clearly switch and a certain electromagnetic and high switching stability of the semiconductor key due to the amplitude filtering of the converted control signal, as well as the ability to control signals of unlimited duration.

In addition, the method can provide high performance of all necessary transformations, since an inertial-free algorithm is implemented when all elements are turned off or on during transformations only by continuous comparison. The speed of the method is limited only by the response time of the transistors used in the circuits of the device.

The disadvantage of the described control method is the possibility of a gradual accumulation of the signal from powerful electromagnetic interference or from the transient voltage on the capacitive filter elements to a level that exceeds the level of the amplitude filtering threshold, and, as a consequence of this process, an erroneous operation of the semiconductor key. Another disadvantage of the described method is that when the input section voltage is not high enough, the inclusion of a semiconductor switch can be delayed by the process of gradual charging of the capacitive filter to the level of the amplitude filtering threshold.

Example 2. The input signal, as in example 1, controls the operation of the active current limiter, which converts it into a sequence of current pulses through the input section of the communication transformer. By changing the parameters of the current pulse, it is possible to significantly expand the range of changes in the supply voltage of the input section while minimizing the average current consumption. Starting from a certain value of the supply voltage of the input section U input _pores , the slew rate of current pulses exceeds a critical value:

They provide a connection between the conversion characteristics of control pulses isolated from each other of the input and output sections and the semiconductor switch:

- establish the optimal ratio between the permissible minimum frequency of current pulses through the input section of the communication transformer and the integrating characteristics of the output section;

через входную секцию трансформатора связи при определенном минимальном напряжении питания входной секции U_вх.пор;- the time interval t _drug counted from the moment the selected voltage reaches the output section of the first threshold level, set corresponding to the critical slew rate of the current amplitude

through the input section of the communication transformer at a certain minimum voltage of the input section U input _pores ;

- the first threshold level is set not exceeding the threshold voltage of the semiconductor key, but such that it provides power and operation of the elements of the output section;

- the second threshold level, which compares the amplitude of the voltage allocated from the output section of the communication transformer after a predetermined time interval, is set to exceed the minimum allowable control voltage of the semiconductor switch

- by setting the amplitude of the current through the primary section of the communication transformer, the amplitude of the selected voltage from the output section exceeds the second threshold level at a certain minimum supply voltage U input _p .

After that, control is established over the fact that the voltage allocated from the output section of the communication transformer exceeds the second threshold level for the time interval t _nar . The time interval is counted from the moment the voltage exceeds the first threshold level. If the voltage allocated from the output section of the communication transformer has exceeded the second threshold level, then it is supplied to the control circuit of the semiconductor key, if not, then the voltage below the first threshold level is set in the circuit of the semiconductor key.

Thus, the electric signal supplied to the input section is optimized in the input section for its efficient transmission beyond the insulation barrier, and by controlling the amplitude and shape of the selected voltage and its transformations in the output section, it takes the form necessary to perform the direct control function of the semiconductor key .

Compared with example 1, the method in example 2 for the same conversion energy costs allows a significant increase in the electromagnetic stability of the semiconductor switch and sets a clear threshold voltage for the input section U input _pore at which the semiconductor switch switches. The disadvantage of this method is the increased delay time for turning off the semiconductor key due to the discharge time of the capacitance of the integrating circuit of the output section to the second threshold level, after turning off the control signal of the semiconductor key from the input section.

Example 3. The transformations of the input signal in the input section are similar to the transformations in example 2. The difference from example 2 is that instead of using its integrating characteristics, the output section uses a special timer to form an additional component of the converting signal, which forms an additional time interval. The signal that the amplitude of the converted pulse control signal exceeds the second threshold level for a specified time interval starts the timer, which gives a signal to turn on the semiconductor key. If, after the completion of the additional time interval, the next signal does not arrive at the timer that the converted pulse signal has exceeded the second threshold level, a signal is generated to turn off the semiconductor key. The additional time interval must exceed the period of the current pulses through the input section of the communication transformer, and the converting signal of one direction should fluctuate from the first to the second threshold level. The minimum allowable timer supply voltage must be below the first threshold level. Compared to example 2, using a timer reduces the turn-off delay time of the semiconductor switch. The disadvantage is the complication of the output section of the semiconductor key and the increase in signal conversion losses.

Example 4. If there is an input control signal, the first active current limiter is activated through the input section of the first communication transformer. In the absence of a control signal, a second current limiter is activated through the input section of the second communication transformer. The signals taken from the output sections of the communication transformers are converted similarly to the transformations described in Example 2. Moreover, the convert signal extracted from the first communication transformer includes a semiconductor key, and the convert signal extracted from the second communication transformer turns off the semiconductor key using an additional key.

The method allows for other options, for example, the introduction of additional functions for the logical processing of the convert signal according to the states of additional threshold levels or additional converts control signals, but unlike example 2, in other options, the energy loss for signal conversion increases.

The endowment of the functions of self-organization of both the input section and the output section isolated from it, as well as the relationship between the signal conversion parameters in the isolated sections, significantly increases the reliability of the semiconductor switch control and ensures the stability of the characteristics of devices implemented on the basis of the proposed control method.

An example implementation of a method for controlling a semiconductor key using a device.

A method for controlling a semiconductor key using a semiconductor device is implemented. An embodiment of a functional diagram of a semiconductor device for implementing a method for controlling a semiconductor key (according to Example 2) is shown in FIG.

The device comprises a housing 1, terminals for connecting a supply voltage of an input section 2, 3, an additional logic control output 4, an input section 5 based on an active current limiter, terminals 6, 7 for connecting an input section 8 of a communication transformer, output section 9 of a communication transformer, terminals 10, 11 for connecting to the output section 9 a communication transformer of the elements of the output section 12, forming a control signal waveform converter. The output section 12 contains a diode 13 connected by one output to the output 10 of the output section of the communication transformer, and the second output to the capacitor 14 and the test point 15, the analysis unit 16, the first current-limiting cascade 17 and one of the outputs of the diode 18 are connected to the same point to which the current-limiting cascade 17 is connected. The second connection point of the current-limiting cascade 17 and the diode 18 is connected to the first output of the additional semiconductor switch 19, the test point 20, the second current-limiting cascade 21 and the control terminal the semiconductor key 22. The output of the analysis unit 16 is connected to the second terminal of the additional semiconductor key 19. An adjustable voltage is supplied to the terminals 23 and 24 of the semiconductor switch 22, and the following is also connected to terminal 24: terminal 11 of the output section of the communication transformer, second terminal of the capacitor 14, third terminal analysis unit 16, the third terminal of the additional semiconductor switch 19 and the second terminal of the second current-limiting stage 21.

The analysis unit 16 (Fig. 8) contains a delay unit 34, a voltage divider across resistors 35 and 36, a reference voltage source 37, a voltage comparator 38, and a current limiting resistor 39.

The device implements a control method as follows.

) импульсов тока 27 не должна быть меньше критического значения:In the turn-on phase of the semiconductor switch 22, the supply voltage of the input section 25 on the buses 2 and 3 is converted into a sequence of current pulses 27 with a limited minimum repetition rate, which are passed through the input section 8 of the communication transformer. At the same time, the amplitude of the current pulses 27 is limited by controlling the duration of the current pulses at the level of restriction 28, which varies depending on the supply voltage 25. Figure 2 shows how, when the supply voltage of the input section 25 changes and the signal 26 is turned on to turn on the semiconductor switch 22 the parameters of the current pulses 27 through the input section 8 of the communication transformer are changed. When the supply voltage 25 increases, the level of amplitude limitation 27 increases, the repetition period increases, and the pulse duration 27 decreases. For the formation of the on phase, the rise rate

) current pulses 27 should not be less than the critical value:

From figure 2 it follows that the transition to the turn-on phase is possible, starting with a certain amplitude of the supply voltage of the input section 5, which determines the threshold supply voltage, above which the semiconductor switch 22 will turn on:

U _Rin ≥u _vh.por - enable zone

U _in ≤ u _in.pore - off zone.

Moreover

where L _I.section - inductance of the input section for a given duration and amplitude of the current pulses 27.

To form the shutdown phase of the semiconductor switch 22, the logical signal 26 is turned off and the current pulses 27 are interrupted.

Figure 3 shows the timing diagrams of the signals in the main nodes of the device based on the functional diagram of figure 1 when modulating and demodulating the input control signal 26 and the formation of a convert control signal 33.

Regardless of whether the semiconductor switch 22 is in the on or off phase, from an alternating voltage 29, caused by a change in the magnetic flux in the turns of sections 8 and 9, taken from the output section 9, the voltage of one direction is allocated by the diode 13 and applied to the capacitor 14. Voltage, which may appear at a test point 20 from the side of the semiconductor switch 22, caused by switching interference, through the diode 18 also enters the capacitance 14.

After exceeding the voltage at the capacitance 14 of the first threshold level 31, with a predetermined delay t _ass , the comparison of the voltage at the capacitance 14 with the reference level (included in the analysis unit 16 and not shown in FIG. 1), specifying the second threshold level 32 by means of the unit analysis 16.

The first threshold level 31 is determined by the minimum voltage from which the analysis unit 16 starts to work and does not exceed the threshold level for switching on the semiconductor switch 22.

The second threshold level 32 is determined by the minimum allowable control voltage of the semiconductor switch 22 and the voltage drop on the first current-limiting element 17 when the key 19 is turned off. From figure 3 it follows that the minimum turn-off delay of the signal 33 is provided when the voltage at the test point 15 at the time of transition to the phase shutdown equal to or lower than the second threshold level 32.

At low speed the voltage rise on the container 14, at which the voltage 30 at the control point 15 does not reach through the second delay interval t _rear threshold level 32, the key 19, with the analyzing unit 16 shunts the control circuit at the reference point 20 (see FIG. 4 )

At a high slew rate on the container 14 the voltage 30 at the control point 15 reaches at the end of interval t _backside second threshold level 32, the key 19 remains open and the voltage 30 is fed through a first current limiting element 17 to the control point 20 where it is divided between the first current-limiting element 17 and the second current-limiting element 21 (see figure 5). The increase in voltage t _bp at the test point 20 occurs with a time constant determined by the resistance of the first current-limiting element 17 and the input capacitance of the semiconductor switch 22. After the turn-on phase of the semiconductor switch 22 is completed, voltage 30 begins to discharge through the first and second current-limiting elements 17 and 21. After the voltage decreases 30 below the second threshold level 32, the analysis unit 16 includes an additional key 19, which shunts the control circuit of the semiconductor key 22 at a test point 20.

Depending on the supply voltage 25 at terminals 2 and 3 for connecting the supply voltage to the input section 5, the invention can provide a voltage amplitude state at a test point 20 either above the second threshold level 32 or below the first threshold level 31. Such an opportunity is provided, for example, by selecting the magnitude and relationship between the current-limiting elements 17 and 21, as well as the delay time t _ass so as to exclude the possibility of the accumulation of voltage 30 from pulse to pulse, as shown in Fig.6.

From figure ₂ and _figure 6 it follows that when U _I ≤ U I _p , and therefore, does not provide a given slew rate of current pulses 27, the voltage at the control point 20 does not exceed the first threshold level 31 and the semiconductor switch 22 remains off condition.

Figure 7 shows the timing diagrams of the control signals 26 on the capacitance 14 and the convert control signal 33 in the conditions of interference with a frequency close to the frequency of the current input section.

Convert control signal 33, semiconductor switch 22, exceeds a second threshold 32, is formed and maintained when the critical rate of change of magnetic flux between the sections 8 and 9 of the transformer connection and amplitude changes in the magnetic flux, ensuring the formation of a predetermined delay time interval t _backside voltage of given amplitude in capacity:

and

or

Where

Uc is the voltage amplitude at the capacitance 14;

Uc _{on min} - voltage on the capacitance 14 corresponding to the second threshold level 32;

- критическая скорость нарастания напряжения на емкости 14;

- the critical slew rate of the capacitance 14;

- критическая скорость изменения магнитного потока.

- critical rate of change of magnetic flux.

If the rate of change of the magnetic flux through the turns of the output section 9 of the communication transformer is insufficient and the specified amplitude of its change, the voltage on the capacitance 14 is small and the voltage level below the first threshold level 31 is set in the control circuit of the semiconductor switch.

The voltage at the capacitance 14 is discharged through the first current-limiting stage 17 for a time not exceeding the period of the current pulses through the input section 8 of the communication transformer.

The value of the capacitance 14 is selected from the condition of its charge in the turn-on phase of the semiconductor switch 22 to a level exceeding the second threshold level, for the normalized delay time t _ass , for a given minimum allowable supply voltage of the input section 5.

The input control signal 26 of the semiconductor key 22 is supplied to the input section 5 in the form of a supply voltage at the terminals 2, 4 and / or in the form of a logical control signal to the terminals 4, 3 and provide with its help the following transformations:

- convert the control signal 26 into a sequence of current pulses 27 through the input section 8 of the communication transformer, the duration of the sequence of current pulses 27 is determined by the duration of the control signal 26, the minimum frequency of the internal analog-to-pulse converter of the input section 5 is determined based on the requirements for the permissible delay and the distortion of the duration of the copied the control signal 26, and the slew rate of the current pulses 27 set at least a critical slew rate of the current;

- when the frequency of the external control signal for controlling the semiconductor switch 22 is lower than the frequency of the internal analog-to-pulse converter of the input section 5, the current frequency of pulses 27 in the input section 8 of the communication transformer is set to the corresponding frequency of the internal analog-pulse converter (not shown in Fig. 1);

- when the frequency of the external control signal 26 is higher than the frequency of the internal analog-pulse converter of the input section 5, the frequency of the pulse current 27 is determined by the corresponding frequency of the external control signal;

- the frequency of the pulses through the input section 8 of the communication transformer is changed depending on the amplitude of the supply voltage 25;

- the ratio between the supply voltage 25 and the pulse frequency 27 is determined by characteristic 28 of the input section 5;

- the duration of the current pulses 27 is determined by the amplitude of the current through the input section 8 of the communication transformer;

- due to magnetic coupling between sections 8 and 9 of the communication transformer, current pulses 27 at the terminals 10 and 11 form alternating voltage pulses;

- isolate the voltage in one direction, removed from the terminals 10, 11 using the diode 13;

- charge the capacitance 14 from the side of terminals 10, 11 and / or from the interference voltage removed from the control point 20;

- apply voltage from the capacitance 14 through the first current-limiting cascade 17 to the control circuit of the semiconductor switch 22 to the test point 20;

- the voltage at the test point 20 is divided between the first and second current-limiting cascades 17 and 21;

- when exceeding on the tank 14 of the first threshold level 31 after a fixed delay time t _back include analysis unit 16;

- depending on the obtained relationship between the second threshold level 32 and the voltage at the control point 15, turn on or off the additional key 19;

- after the end of the on phase, the signal 26 is interrupted, the sequence of current pulses 27 is interrupted, respectively, the voltage on the capacitance 14 decreases below the second threshold level, the additional semiconductor switch 19 is turned on, the semiconductor switch 22 is turned off.

The semiconductor switch 22 relates to voltage controlled devices. From figure 9 it follows that it is possible to control semiconductor devices controlled by current, for example thyristors. As shown in Fig. 9, a semiconductor switch 22, connected by a resistor 40 in the current limiter mode, supplies a current generated to the terminals 42 and 43 to the control circuit of the semiconductor switch 41. Current flows through the control circuit of the switch 41 with the moment of supplying voltage to the control circuit of the semiconductor key 22 to the moment of turning on the semiconductor key 41.

The technical result, which is achieved by the invention, is reduced to the creation of a semiconductor switch control technology, which makes it possible to create devices with isolation based on magnetic coupling. The invention ensures that the signal 33 will repeat the input signal 26 with a given delay and a given distortion of its duration, with the possibility of changing the duration of the signal 26 up to a constant component, and the amplitude of the signal 33 will ensure the full inclusion of the semiconductor switch 22.

The invention surpasses the capabilities of known technologies for controlling a semiconductor key without using an additional power source in the isolated output section of the semiconductor key in terms of stability characteristics and reliability. The dynamic characteristics of the control signal 26 are limited only by the speed of the transistors that are used in the device that implements the invention.

Having considered a possible variant of the technical implementation of the invention, it is necessary to take into account the possibility of its implementation in other schemes or combinations of schemes.

The invention allows the possibility of combining devices into multi-channel control modules. For example, with one control source and a power source at the input and multiple outputs isolated from each other.

Based on the invention, a workable multi-channel key management device based on MOS transistors with an input capacitance of up to 1000 pF and the following combinations of characteristics and maximum permissible values is implemented:

- the threshold input voltage (U _input ) is adjustable from 3 to 30 V with a current consumption per channel of up to 10 mA at a case temperature of 25 ° C and 20 mA at a case temperature of 125 ° C;

- turn on and off time no more than 1 μs;

- isolation voltage between input and output 10 kV;

- operating common mode voltage up to 2500 V;

- passage capacity not more than 5 pF;

- turn-on phase time from 2 μs to continuous turn-on;

- the critical rate of voltage rise in the closed state of the switch is at least 2500 V / μs.

The first threshold level was 1.8 V; the second threshold level was 9 V, the conversion frequency was from 200 to 500 kHz.

The device remained operable when exposed to electromagnetic transformer coupling of electromagnetic fields with a frequency of 50 Hz when placed directly on power buses with currents up to 10 kA.

Using the capabilities of the present invention, it is possible to create insulating devices for controlling semiconductor switches with significant advantages compared with the prototype and other known technical solutions.

Claims (1)

A method for controlling a semiconductor switch with isolated input and output sections and a communication transformer based on the electromagnetic effect between them, which consists in converting the supply voltage of the input section into current pulses through the input section of the communication transformer, with a limitation of the amplitude of the current pulses by controlling their duration and repetition rate, and selection on the output section of the communication transformer of the convert control signal of the semiconductor key, characterized in that set the time The amplitude of the current pulses through the input section of the communication transformer to a predetermined level with a duration not exceeding the critical value, and to turn the semiconductor switch on or off, or to keep it on or off, is controlled after a specified time interval, counted from the moment the voltage reaches one the direction allocated from the output section of the communication transformer, the first threshold level, the fact that the selected voltage exceeds one second direction threshold level, while the first threshold level is set not exceeding the threshold voltage of the semiconductor key, and the second threshold level is set to exceed the minimum allowable control voltage of the semiconductor key, and the control results regulate the voltage of one direction allocated from the output section of the communication transformer in the control circuit of the semiconductor key .

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