CN211061674U

CN211061674U - IPM module short circuit detection circuit

Info

Publication number: CN211061674U
Application number: CN201921657080.2U
Authority: CN
Inventors: 孟昭亮; 方正鹏; 高勇; 杨媛; 艾胜胜; 卢志鹏; 吕亚茹
Original assignee: Xian Polytechnic University
Current assignee: Xian Polytechnic University
Priority date: 2019-09-30
Filing date: 2019-09-30
Publication date: 2020-07-21
Anticipated expiration: 2029-09-30

Abstract

The utility model discloses a IPM module short circuit detection circuitry, including connecting low resistance value resistance R, the filter circuit that amplifies, protection circuit and the drive circuit between IPM module projecting pole terminal and grid terminal, amplify filter circuit and gather amplifier resistance R's electric current, protection circuit converts the electric current signal who enlargies into voltage signal U to with threshold voltage U _refMaking a comparison if U <U_refThe protection circuit outputs a low level signal to the drive circuit, and the drive circuit drives the IPM module to normally work; if U is more than or equal to U _refThe protection circuit outputs a high level signal to the driving circuit, and the driving circuit turns off the IPM module. The utility model discloses short-circuit inspection The circuit collects the current of the amplifying resistor R through the amplifying filter circuit, the required time is extremely short, interference current burrs are filtered, the threshold value can be set easily after the current is amplified, the IPM module short circuit detection time is effectively shortened, and the protection effect is improved.

Description

IPM module short circuit detection circuit

Technical Field

The utility model belongs to the technical field of intelligent power module protection circuit, a IPM module short circuit detection circuit is related to.

Background

IPM (Intelligent Power Module), i.e. an Intelligent Power Module, integrates not only the Power switch device and the driving circuit. And fault detection circuits such as overvoltage, overcurrent and overheat are integrated in the CPU, and detection signals can be sent to the CPU. The high-speed low-power-consumption transistor consists of a high-speed low-power-consumption transistor core, an optimized gate driving circuit and a quick protection circuit. Even if a load accident or misuse occurs, it is possible to ensure that the IPM itself is not damaged.

In recent years, IPM modules have been widely used in various fields such as automotive electronics, locomotive traction, and new energy. With the further application of the IPM module in various fields, the requirements for the IPM module and the application thereof are further improved, and since the high-power IPM module usually works under the condition of high voltage and large current, the IPM module is damaged by short circuit in the system operation process, which seriously affects the application thereof. Therefore, short circuit detection of IPM modules is one of the key technologies.

Because the switching speed of the IPM module is faster and faster, the current of the IPM module is 4-6 times of the rated current when the IPM module is in short circuit, if the short circuit fault cannot be detected quickly, the protection circuit cannot perform device protection at the first time, and the damage of the IPM module is inevitably caused, so the requirement on the precision of short circuit monitoring of the IPM module is higher and higher, the disadvantage of the traditional IPM module desaturation detection method is more and more obvious, and the misoperation under the desaturation short circuit detection method is more likely to be caused due to the inaccuracy of the set reference voltage. This is mainly due to the use of V _ceWhen the saturation is removed, the detection blind area (1-8 microsecond) The detection effect is not ideal because the emitter voltage detection threshold is set to be relatively high due to the relatively long length.

Disclosure of Invention

The utility model aims at providing a IPM module short circuit detection circuitry has solved current IPM module and has moved back the saturated short circuit and detect because of detecting the blind area time long, makes the IPM module take place the problem of damage.

The utility model provides an adopted technical scheme is, an IPM module short circuit detection circuitry, including connecting low resistance R, amplification filter circuit, protection circuit and the drive circuit between IPM module projecting pole terminal and grid terminal, amplification filter circuit gathers amplification resistance R's electric current, and protection circuit converts the electric current signal of enlarging into voltage signal U to with threshold voltage U _refMaking a comparison if U <U_refThe protection circuit outputs a low level signal to the drive circuit, and the drive circuit drives the IPM module to normally work; if U is more than or equal to U _refThe protection circuit outputs a high level signal to the driving circuit, and the driving circuit turns off the IPM module.

The utility model is also characterized in that,

The resistance value of the resistor R is 0.4-1.5 ohm.

The protection circuit is including the resistance R1, high-voltage diode D2, resistance R2, amplitude limiting circuit and the comparator that connect gradually, and amplitude limiting circuit includes diode VD1 and diode VD2, diode VD1 input connects +15V power and resistance R2 respectively in the amplitude limiting circuit, and diode VD1 output is connected with diode VD2 input, and diode VD2 output ground, and high-voltage diode D2 output is connected with diode VD2 input, and diode VD1 output is connected with the comparator input, the filter circuit that amplifies is connected with resistance R1.

The driving circuit comprises a power amplification module.

The amplification factor of the amplifying and filtering circuit is 20 times.

The utility model has the advantages that the short-circuit detection circuit of the IPM module is formed by arranging the low-resistance resistor R, the amplifying filter circuit, the protection circuit and the driving circuit which are connected with each other between the emitter terminal and the grid terminal of the IPM module, the amplifying filter circuit can amplify the current signal flowing through the resistor R, the time required by current collection is extremely short, interference current burrs are filtered, the setting of threshold current value is easier to be carried out after current amplification, the accuracy of short-circuit current detection is effectively improved, and the short-circuit detection time is shortened; the amplified current signal is transmitted to the protection circuit, so that the protection circuit can detect whether the IPM module is short-circuited in a short time, the IPM module is protected, and the phenomenon that a chip in the IPM module is burnt due to the fact that the chip bears overlarge short-circuit current is avoided, so that the reliability of the IPM module is improved, and the service life of the IPM module is prolonged.

Drawings

FIG. 1 is a schematic diagram of an IPM module short circuit detection circuit of the present invention;

FIG. 2 is a schematic diagram of a protection circuit in the IPM short circuit detection circuit of the present invention;

Fig. 3 is a comparison graph of the short-circuit detection circuit of the IPM module of the present invention.

In the figure, 1, IPM module, 3, amplifying and filtering circuit, 4, protection circuit, 5, driving circuit and 7, resistor R.

Detailed Description

The present invention will be described in detail with reference to the accompanying drawings and specific embodiments.

The utility model relates to a IPM module short circuit detection circuitry, refer to fig. 1, including connecting resistance R7, amplification filter circuit 3, protection circuit 4 and the drive circuit 5 between IPM module 1 projecting pole terminal and grid terminal, amplification filter circuit 3 gathers amplification resistance R7's electric current, and protection circuit 4 converts the electric current of enlargeing into voltage U to with threshold voltage U _refMaking a comparison if U <U_refThe protection circuit 4 outputs a low level signal to the driving circuit 5, and the driving circuit 5 drives the IPM module 1 to normally work; if U is more than or equal to U _refThe protection circuit 4 outputs a high level signal to the driving circuit 5, which indicates that the IPM module 1 is short-circuited, and the driving circuit 5 turns off the IPM module 1. In this embodiment, the IPM module 1 has a rated current of 150A and a rated voltage of 1700V. The short circuit current value of the IPM module is 4-6 times of the rated current, the current amplification factor of the amplifying and filtering circuit 3 is 20 times, The resistance of the resistor R7 is 1 ohm, so the threshold voltage U _ref＝150×4×20×1＝12000V。

Referring to fig. 2, the protection circuit 4 includes a resistor R1, a high voltage diode D2, a resistor R2, a limiting circuit and a comparator, which are connected in sequence, the limiting circuit includes a diode VD1 and a diode VD2, an input terminal of the diode VD1 in the limiting circuit is respectively connected to a +15V power supply and the resistor R2, an output terminal of the diode VD1 is connected to an input terminal of the diode VD2, an output terminal of the diode VD2 is grounded, an output terminal of the high voltage diode D2 is connected to an input terminal of the diode VD2, an output terminal of the diode VD1 is connected to an input terminal of the comparator, and the amplifying filter circuit.

The amplifying filter circuit amplifies the collected current flowing through the resistor R7 and inputs the current into the protection circuit, the current forms voltage through the resistor R1, the high-voltage diode D2 prevents the high voltage at the power side from causing interference to the front-end comparator, the diode VD1 and the diode VD2 form an amplitude limiting circuit, the voltage between the diode VD1 and the diode VD2 can be prevented, namely the voltage U at the point A exceeds the input allowable range of the comparator, and the threshold voltage U is higher than the threshold voltage U _refThe voltage is generated by dividing the voltage by two precise resistors if the voltage U is at the point A <U_refThe comparator outputs a low level signal to indicate that the IPM module is not short-circuited and works normally; if the voltage U at the point A is not less than U _refThe comparator outputs a high signal indicating that the IPM module 1 is short-circuited.

The driving circuit 5 comprises a driving selection circuit and a power amplification module which are connected, the output end of the comparator is connected with the input end of the driving selection circuit, the output end of the power amplification module is connected with the gate terminal of the IPM module 1, the IPM module is a voltage-driven power module, the switching behavior of the IPM module is equivalent to that a large instantaneous peak current is injected into or pumped out of a gate, and the gate capacitance is controlled to charge and discharge. The power amplification module, namely the power amplifier, can amplify the received signal power to the maximum value, namely amplifying the power of the on/off signal of the IPM module to the maximum value to drive the on/off of the IPM module.

Adopt the utility model discloses IPM module short-circuit detection circuit and current saturation detection circuit that moves back carry out the short-circuit detection to IPM module, and the result is as shown in FIG. 3, and in FIG. 3, the axis of ordinates Vce is The voltage between the collector and the emitter of the IPM module is represented by time on the horizontal axis, and the uppermost dotted line in the graph represents the change trend of the voltage between the collector and the emitter of the IPM module along with the time after the IPM module is subjected to short-circuit fault; the middle solid line represents the time-varying trend of the voltage between the collector and the emitter of the IPM module when the IPM module normally works, namely, when no short circuit occurs; the bottom dotted line represents the time variation trend of the threshold voltage Vref set by the existing desaturation detection circuit; when the IPM module is short-circuited, the time required for the IPM module short-circuit detection circuit to test the short-circuit fault is t ₁The time required for the existing desaturation detection circuit to test the short-circuit fault is t ₂As can be seen from FIG. 3, t is ₂≈2t₁The utility model discloses the required check-out time of IPM module short-circuit detection circuit is shorter, can in time turn-off IPM module when the short circuit takes place for IPM module, has avoided IPM module inner chip to take place to damage, has improved IPM module's reliability and life.

Claims

1. The short-circuit detection circuit of the IPM module is characterized by comprising a resistor R (7), an amplification filter circuit (3), a protection circuit (4) and a driving circuit (5), wherein the resistor R (7), the amplification filter circuit (3), the protection circuit (4) and the driving circuit are connected between an emitter terminal and a gate terminal of the IPM module (1), the amplification filter circuit (3) collects current of the amplification resistor R (7), the protection circuit (4) converts an amplified current signal into a voltage signal U, and the voltage signal U is connected with a threshold voltage U _refMaking a comparison if U <U_refThe protection circuit (4) outputs a low level signal to the driving circuit (5), and the driving circuit (5) drives the IPM module (1) to normally work; if U is more than or equal to U _refThe protection circuit (4) outputs a high level signal to the drive circuit (5), and the drive circuit (5) turns off the IPM module (1).

2. The IPM module short circuit detection circuit of claim 1, wherein said resistor R (7) has a resistance of 0.4-1.5 ohm.

3. The IPM module short circuit detection circuit of claim 2, wherein said protection circuit (4) comprises a resistor R1, a high voltage diode D2, a resistor R2, a limiter circuit and a comparator connected in sequence, the limiter circuit comprises a diode VD1 and a diode VD2, the input terminal of the diode VD1 in the limiter circuit is connected to the +15V power supply and the resistor R2, the output terminal of the diode VD1 is connected to the input terminal of the diode VD2, the output terminal of the diode VD2 is connected to the ground, the output terminal of the high voltage diode D2 is connected to the input terminal of the diode VD2, the output terminal of the diode VD1 is connected to the input terminal of the comparator, and said amplification filter circuit (3) is connected to the resistor R1.

4. An IPM module short circuit detection circuit according to claim 3, characterised in that said driving circuit (5) comprises a power amplifying module (2).

5. An IPM module short-circuit detection circuit according to claim 3, wherein said amplification filter circuit (3) has a 20-fold amplification factor.