阅读说明：本技术 一种igbt模块驱动窄脉冲抑制方法 (IGBT module driving narrow pulse suppression method ) 是由 李树奎 于 2021-08-02 设计创作，主要内容包括：本发明公开了一种IGBT模块驱动窄脉冲抑制方法,包括如下步骤：获取抑制触发驱动窄脉冲；抑制关断驱动窄脉冲处理；获得抑制驱动窄脉冲。本发明的方法通过软件编程实现,逻辑简单明了,实现了IGBT模块驱动脉冲的精确控制,确保了IGBT模块的稳定运行,提高了IGBT模块工作的安全性。(The invention discloses a method for restraining narrow pulse driven by an IGBT module, which comprises the following steps: acquiring a trigger-suppressed driving narrow pulse; the narrow pulse processing of the turn-off drive is restrained; a suppressed driving narrow pulse is obtained. The method is realized through software programming, the logic is simple and clear, the accurate control of the driving pulse of the IGBT module is realized, the stable operation of the IGBT module is ensured, and the working safety of the IGBT module is improved.)

1. A method for suppressing narrow pulse driven by an IGBT module is characterized by comprising the following steps:

acquiring a trigger-suppressed driving narrow pulse:

1) acquiring single high level action time T1 of the driving pulse, and setting the filtered trigger narrow pulse to be a low level when T1 is judged to be smaller than set time Td; when the T1 is judged to be more than or equal to the set time Td, the filtering triggering narrow pulse is set to be a high level; carrying out AND logic operation on the driving pulse and the filtered triggering narrow pulse to obtain a narrow pulse;

2) acquiring single high level action time T2 of the narrow pulse, and setting the widened driving pulse as a high level when judging that T2 is smaller than a preset minimum pulse width Tmin; when the T2 is judged to be more than or equal to the preset minimum pulse width Tmin, setting the broadening driving pulse to be at a low level;

3) carrying out OR logic operation on the drive pulse and the widened drive pulse to obtain a narrow pulse for suppressing and triggering drive;

and (3) narrow pulse processing of restraining turn-off driving:

acquiring single high level action time T3 of the drive narrow pulse for restraining triggering, and setting the drive narrow pulse for restraining turning off as high level when judging that T3 is smaller than the maximum pulse width Tmax; when the T3 is judged to be more than or equal to the maximum pulse width Tmax, the drive narrow pulse for restraining the turn-off is set to be at a low level; the maximum pulse width Tmax is T-Tmin, wherein T is a switching period;

obtaining a suppressed drive narrow pulse:

and performing AND logic operation on the suppression turn-off driving narrow pulse and the suppression trigger driving narrow pulse to obtain the suppression driving narrow pulse.

2. The IGBT module driving narrow pulse suppression method according to claim 1, wherein the set time Td is a dead time of the complementary tube driving pulse, and Td is 2.5 μ β.

3. The IGBT module driving narrow pulse suppression method according to claim 2, wherein the preset minimum pulse width Tmin is 1 μ s or 1.5 μ s.

4. The IGBT module driving narrow pulse suppression method according to claim 3, wherein the switching period T is 1/f, where f is a switching frequency of pulse width modulation.

Technical Field

The invention relates to the technical field of IGBT module driving narrow pulse suppression, in particular to a method for suppressing IGBT module driving narrow pulse.

Background

In products in the field of industrial control such as frequency converters, UPS power supplies and active power filters, an Insulated Gate Bipolar Transistor (IGBT) module is used as a core device for energy conversion and transmission, the IGBT is required to have higher stability and reliability, and the IGBT driving narrow pulse poses great threat to the reliable operation of the IGBT module and is an important factor for causing the failure of the IGBT module. For the narrow pulse triggered by the IGBT drive, the IGBT enters a reverse recovery state immediately after being conducted in a very short time without accumulating a sufficient number of carriers, and a voltage is applied to generate stronger di/dt, du/dt; for the IGBT driving turn-off narrow pulse, which is equivalent to an anti-parallel diode of another IGBT of the same bridge arm, the action of incomplete turn-on and immediate turn-off can occur, and du/dt or oscillation which is more serious than the IGBT triggering narrow pulse is generated. After the IGBT module drives the narrow pulse for many times, it is damaged and cannot operate reliably, so to realize reliable application of the IGBT, triggering and turning off the narrow pulse should be limited.

In the prior art, a hardware circuit is mostly adopted to suppress the driving narrow pulse, but the action time of the driving narrow pulse is changed due to errors of hardware circuit devices. The operating stability of the IGBT module is yet to be further improved.

Disclosure of Invention

In view of the above-mentioned drawbacks and deficiencies of the prior art, it is desirable to provide a method for suppressing a narrow pulse for driving an IGBT module, which can precisely control a narrow pulse for driving and ensure a stable operation of the IGBT module.

The invention provides a method for restraining narrow pulse driven by an IGBT module, which comprises the following steps:

acquiring a trigger-suppressed driving narrow pulse:

1) acquiring single high level action time T1 of the driving pulse, and setting the filtered trigger narrow pulse to be a low level when T1 is judged to be smaller than set time Td; when the T1 is judged to be more than or equal to the set time Td, the filtering triggering narrow pulse is set to be a high level; carrying out AND logic operation on the driving pulse and the filtered triggering narrow pulse to obtain a narrow pulse;

2) acquiring single high level action time T2 of the narrow pulse, and setting the widened driving pulse as a high level when judging that T2 is smaller than a preset minimum pulse width Tmin; when the T2 is judged to be more than or equal to the preset minimum pulse width Tmin, setting the broadening driving pulse to be at a low level;

3) carrying out OR logic operation on the drive pulse and the widened drive pulse to obtain a narrow pulse for suppressing and triggering drive;

and (3) narrow pulse processing of restraining turn-off driving:

acquiring single high level action time T3 of the drive narrow pulse for restraining triggering, and setting the drive narrow pulse for restraining turning off as high level when judging that T3 is smaller than the maximum pulse width Tmax; when the T3 is judged to be more than or equal to the maximum pulse width Tmax, the drive narrow pulse for restraining the turn-off is set to be at a low level; the maximum pulse width Tmax is T-Tmin, wherein T is a switching period;

obtaining a suppressed drive narrow pulse:

and performing AND logic operation on the suppression turn-off driving narrow pulse and the suppression trigger driving narrow pulse to obtain the suppression driving narrow pulse.

Further, the set time Td is a dead time of the complementary driving pulse, and Td is 2.5 μ s.

Further, the preset minimum pulse width Tmin is 1 μ s or 1.5 μ s.

Further, the switching period T is 1/f, where f is a switching frequency of the pulse width modulation.

Compared with the prior art, the invention has the beneficial effects that:

the method filters the action time of the driving pulse to be less than the dead time Td, prolongs the action time of the driving pulse to be more than the dead time Td and prolongs the narrow pulse to be less than Tmin + Td to be the action time of the Tmin + Td, so that the narrow pulse is eliminated, and the aim of inhibiting triggering of the driving narrow pulse is fulfilled.

The off-drive narrow pulse is required to be performed immediately, so the dead time filtering process is not performed. The suppression turn-off driving narrow-break pulse and the suppression trigger driving narrow-break pulse are subjected to AND logic operation, the purpose is to indirectly widen the action time of the turn-off driving narrow pulse to Tmin by limiting the action time of the suppression trigger driving narrow pulse, and finally the suppression drive narrow pulse is obtained, so that the suppression trigger driving narrow pulse is realized, and the suppression turn-off driving narrow-break pulse is also realized.

The method is realized through software programming, the logic is simple and clear, the accurate control of the driving pulse of the IGBT module is realized, the stable operation of the IGBT module is ensured, and the working safety of the IGBT module is improved.

It should be understood that the statements herein reciting aspects are not intended to limit the critical or essential features of any embodiment of the invention, nor are they intended to limit the scope of the invention. Other features of the present invention will become apparent from the following description.

Drawings

Other features, objects and advantages of the invention will become more apparent upon reading of the detailed description of non-limiting embodiments made with reference to the following drawings:

FIG. 1 is a flow chart for obtaining suppressed trigger drive narrow pulses;

fig. 2 is a flowchart of acquiring the suppression driving narrow pulse.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the relevant invention and not restrictive of the invention. It should be noted that, for convenience of description, only the portions related to the present invention are shown in the drawings.

It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

Referring to fig. 1 to fig. 2, an embodiment of the present invention provides a method for suppressing a narrow pulse driven by an IGBT module, including the following steps:

(1) acquisition inhibit trigger drive narrow pulse PWMQ 1:

1) detecting the rising edge of a drive pulse Qup of an IGBT module, starting timing until the first falling edge, acquiring single high-level action time T1 of the drive pulse Qup, judging, and if T1 is less than set time Td, the Td is dead time, preferably, the Td is 2.5 mu s, setting a filtering trigger narrow pulse pwnuen to be low level, namely, pwnuen is 0; if the time T1 is greater than or equal to the set time Td, setting the filtered trigger narrow pulse pwnuen to be a high level, that is, pwnuen is 1; performing AND logic operation on the drive pulse Qup and the filtered trigger narrow pulse pwnuen, namely Qup and logic pwnuen, and obtaining a narrow pulse Qupt with the filtering time smaller than the dead time Td in the drive pulse Qup;

in the application of the inverter, in order to prevent the shoot-through, dead time Td is added to the IGBT module which is driven complementarily, so that the narrow pulse Qupt which is less than the dead time Td does not need to be processed, and the narrow pulse Qupt which is less than the dead time Td in action time in the driving pulse Qup is filtered.

2) Detecting a rising edge of the narrow pulse Qupt, starting timing until the first falling edge, acquiring a single high level action time T2 of the narrow pulse Qupt, judging, and if T2 is smaller than a preset minimum pulse width Tmin, preferably, Tmin is 1 mu s, setting a broadening driving pulse Quptd as a high level, namely, the Quptd is 1; if T2 is greater than or equal to the preset minimum pulse width Tmin, setting the widened driving pulse qptd to be low level, that is, qptd is 0;

wherein, the preset minimum pulse width Tmin is the minimum pulse width set by the driving pulse Qup;

the widened driving pulse qptd is obtained by extending a narrow pulse qpt larger than the dead time Td and smaller than the Tmin + Td pulse action time to Tmin + Td (3.5 μ s) to eliminate the narrow pulse.

3) Carrying out OR logic operation on the drive pulse Qup and the widened drive pulse Quptd to obtain a suppression trigger drive narrow pulse PWMQ 1;

the purpose of suppressing the triggering of the driving narrow pulse PWMQ1 is to filter out the pulse with the action time of the driving pulse Qup being less than the dead time Td, and carry out pulse continuation on the pulse with the action time of the driving pulse Qup being more than the dead time Td and less than Tmin + Td, so as to prolong the pulse action time of Tmin + Td, and eliminate the driving narrow pulse, thereby achieving the purpose of suppressing the triggering of the driving narrow pulse signal.

(2) Inhibit-off drive narrow pulse pwmden treatment:

acquiring single high level action time T3 of the drive narrow pulse for restraining triggering, and setting the drive narrow pulse for restraining turning off as high level when judging that T3 is smaller than the maximum pulse width Tmax; when the T3 is judged to be more than or equal to the maximum pulse width Tmax, the drive narrow pulse for restraining the turn-off is set to be at a low level;

detecting the rising edge of the suppression trigger driving narrow pulse PWMQ1, starting timing until the first falling edge, acquiring single high-level action time T3 of a suppression trigger driving narrow pulse signal PWMQ1, judging, and if T3 is smaller than the maximum pulse width Tmax, setting the suppression shutdown driving narrow pulse pwmden to be high level, namely pwmden is 1; if T3 is equal to or greater than the maximum pulse width Tmax, the inhibit-off drive narrow pulse pwmden is set to low level, that is, pwmden is equal to 0; the maximum pulse width Tmax is T-Tmin, wherein T is a switching period;

the switching period is a fixed value, and the switching period T is 1/f, where f is the switching frequency of the control, i.e., the switching frequency of the pulse width modulation.

Example (c): when f is 12.8kHz, T is 78.125 μ s, Tmin is 1 μ s, and Tmax is 77.125 μ s.

(3) Obtaining a suppressed drive narrow pulse:

and (3) carrying out AND logic operation on the suppression cut-off driving narrow pulse pwmden and the suppression trigger driving narrow pulse PWMQ1 to obtain a suppression driving narrow pulse PWMQ1 d.

The application widens the suppression of the shutdown driving narrow pulse pwmden to the minimum pulse action time Tmin by suppressing the driving action time of the trigger driving narrow pulse PWMQ1, and obtains the suppression driving narrow pulse PWMQ1 d. The IGBT module driving pulse control method and device are achieved through software programming, logic is simple and clear, accurate control of IGBT module driving pulse is achieved, stable operation of the IGBT module is guaranteed, and working safety of the IGBT module is improved.

In the description of the present specification, the terms "connect", "mount", "fix", and the like are to be understood in a broad sense, for example, "connect" may be a fixed connection, a detachable connection, or an integral connection; may be directly connected or indirectly connected through an intermediate. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

In the description of the present application, the description of the terms "one embodiment," "some embodiments," etc. means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the application. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.