CN111313881A - Method for improving anti-interference performance of IGBT driver - Google Patents
Method for improving anti-interference performance of IGBT driver Download PDFInfo
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- CN111313881A CN111313881A CN201811507254.7A CN201811507254A CN111313881A CN 111313881 A CN111313881 A CN 111313881A CN 201811507254 A CN201811507254 A CN 201811507254A CN 111313881 A CN111313881 A CN 111313881A
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- 238000000034 method Methods 0.000 title claims abstract description 34
- 238000001514 detection method Methods 0.000 claims abstract description 20
- 230000001629 suppression Effects 0.000 claims abstract description 16
- 230000001052 transient effect Effects 0.000 claims abstract description 16
- 238000010521 absorption reaction Methods 0.000 claims abstract description 8
- 239000003990 capacitor Substances 0.000 claims description 25
- 230000036039 immunity Effects 0.000 claims description 4
- 230000035772 mutation Effects 0.000 claims description 4
- 230000000694 effects Effects 0.000 abstract description 4
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- 230000015556 catabolic process Effects 0.000 description 1
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- 230000006872 improvement Effects 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
- H03K17/51—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used
- H03K17/56—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices
- H03K17/567—Circuits characterised by the use of more than one type of semiconductor device, e.g. BIMOS, composite devices such as IGBT
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03K—PULSE TECHNIQUE
- H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
- H03K17/16—Modifications for eliminating interference voltages or currents
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Abstract
The invention discloses a method for improving the anti-interference performance of an IGBT driver, which comprises the step of arranging an external constant current source, a pi-type resistance-capacitance absorption circuit, a transient suppression diode and corresponding control logic between pins of the driver, solves the problem of poor anti-interference performance caused by small current of the constant current source in the driver, enhances the filtering effect of an IGBT fault detection circuit, and limits the amplitude of peak voltage generated by a C pole and an E pole in the turn-on and turn-off processes of the IGBT and absorbs the energy of the peak voltage.
Description
Technical Field
The invention belongs to the field of IGBT drivers, and particularly provides a method for improving the anti-interference performance of an IGBT driver.
Background
With the continuous and dramatic development of integrated circuit design and manufacturing technology, the functions of the circuit system are more and more powerful, but the composition is more and more simple, and the current modularization technology of power electronic products is particularly prominent, which puts higher requirements on the whole design. The importance of software design goes undoubtedly, but the importance of hardware circuit design is more neglected, and most components are integrated in an integrated PCB circuit board in the modularized design, so that the problems of coexistence of small control signals and high-voltage and high-current signals and the like are inevitable.
An Insulated Gate Bipolar Transistor (IGBT) is a novel power electronic switching device, and has the characteristics of easy driving, and also has the advantages of large tube voltage and current capacity, and the like. The operating frequency of the IGBT is in the frequency range of several tens of kHz, and therefore, the IGBT occupies a major application position in high-frequency, medium-power electronic equipment. The IGBT drive circuit integrates the characteristics of an MOS tube and a bipolar triode, has the advantages of high frequency, high voltage resistance, large current, small on-resistance and the like, is applied to a circuit system with high voltage and large current, and has the functions of overvoltage protection, short-circuit protection, reliable turn-off and the like, so that the design of the IGBT drive circuit is very important.
At present, the IGBT is driven by an IGBT driving chip, the IGBT driving chip provides a trigger pulse signal when the IGBT is normally turned on and turned off, and the IGBT is turned off when the IGBT breaks down, so that damage caused by overcurrent is avoided. During normal operation, the spike pulse voltage caused by turn-on and turn-off of the IGBT may interfere with a fault detection circuit that is mainly composed of the desaturation voltage input pin DESAT and is matched with other pins and related components, thereby causing the IGBT to turn off by mistake.
Disclosure of Invention
This patent has provided improvement measure to the fault detection circuit of traditional control chip, avoids switching on the interference of turn-off in-process spike pulse to cause power electronic switch such as IGBT to start short-circuit protection and turn-off. A method for improving the anti-interference performance of an IGBT driver by adding a corresponding anti-interference design circuit into a fault detection circuit of the driver is provided, and the method comprises the following steps:
(1): at the gate drive output voltage pin (V) of the IGBT driverOPin) and a desaturation voltage input pin (DESAT pin) of the driver;
(2): at the desaturation voltage input pin (DESAT pin) of the IGBT driver and the output supply voltage pin (V) of the driverEPins) are arranged between the two circuits;
(3): at the desaturation voltage input pin (DESAT pin) of the IGBT driver and the output supply voltage pin (V) of the driverEPin) is provided with a transient suppression diode.
(4): when the FAULT signal of the FAULT pin of the IGBT driver is output and reported to the controller, the controller should emergently close other normally working IGBTs or keep the opening state of part of the IGBTs to enable the current of the device to smoothly flow through the load, so as to avoid current mutation, and after the FAULT of the FAULT pin of the driver disappears, the IGBT switching logic is changed into a normal state to continue working.
The method for setting the external constant current source comprises the following steps: at the output voltage pin (V)OPin) driving resistor RGOutput terminal and dead zone capacitor CBLANKA constant current source is connected between the two capacitors, and the current of the constant current source is opposite to the blind area capacitor CBLANKCharging; the blind area capacitor CBLANKSet at the desaturation voltage input pin (DESAT pin) and the output supply voltage pin (V)EPins).
The method for setting a pi-type resistor-capacitor absorption circuit comprises connecting a blind area capacitor C at one end of a detection resistor R of a desaturation voltage input pin (DESAT pin) of a driverBLANKOne end of the detection resistor R is connected with the other endCapacitor C1BLANKC1BLANKThe other end of the first and second terminals is connected with an output power supply voltage pin (VEPin) from C1BLANKDetecting resistance and CBLANKForming a pi-type RC absorption circuit.
The method for arranging a transient suppression diode is to connect the anode of the transient suppression diode with the output power supply voltage pin (V)EPin), a detection resistor R and a detection diode D of a cathode of the transient suppression diode and a desaturation voltage input pin (DESAT pin)DESATAre connected.
The driver is FOD8332, C1BLANKThe capacitance value is of nF order.
The invention has the technical effects that: by implementing the method for improving the anti-interference performance, the problem of poor anti-interference performance caused by small current of the constant current source in the driver is solved, the filtering effect of the IGBT fault detection circuit is enhanced, the amplitude of peak voltage generated by the C pole and the E pole in the turn-on and turn-off processes of the IGBT is limited, and the energy of the peak voltage is absorbed. And the anti-interference performance of the driver is further improved by matching the driver with the control logic design of the device.
Drawings
FIG. 1 is a diagram of a common application circuit of an IGBT driver
FIG. 2 is a circuit structure diagram for improving the anti-interference performance of the IGBT driver
FIG. 3 is a flow chart of a method for improving the anti-interference performance of an IGBT driver
Detailed Description
The present invention will be described below based on examples, but the present invention is not limited to only these examples. In the following detailed description of the present invention, certain specific details are set forth. It will be apparent to one skilled in the art that the present invention may be practiced without these specific details. Well-known methods, procedures, components and circuits have not been described in detail so as not to obscure the present invention.
Further, those of ordinary skill in the art will appreciate that the drawings provided herein are for illustrative purposes and are not necessarily drawn to scale.
Meanwhile, it should be understood that, in the following description, a "circuit" refers to a conductive loop constituted by at least one element or sub-circuit through electrical or electromagnetic connection. When an element or circuit is referred to as being "connected to" another element or element/circuit is referred to as being "connected between" two nodes, it may be directly coupled or connected to the other element or intervening elements may be present, and the connection between the elements may be physical, logical, or a combination thereof. In contrast, when an element is referred to as being "directly coupled" or "directly connected" to another element, it is intended that there are no intervening elements present.
The drivers sold on the market at present mostly adopt a current source type to detect IGBT saturation voltage reduction, the current of a current source in the drivers is very small, and the capacitance value of an external blind area capacitor is very small, so that the anti-interference performance is poor, and IGBT error protection is easy to occur. Taking the FOD8332 chip as an example, the FOD8332 is an advanced 2.5A output current IGBT driving photoelectric coupler which can drive medium-sized power IGBTs up to 1200V and 150A. The method is suitable for the application of a motor control inverter and the quick switch driving of the IGBT and the MOSFET in a high-performance power system. The FOD8332 may provide the necessary protection from failure to ensure that the IGBT is not damaged by overheating. The device adopts the Optoplanar coplanar packaging technology special for the femto, optimizes the IC design, and realizes reliable high isolation voltage and high noise resistance through the specification characteristics of high common mode rejection and power supply rejection. The device is contained in a broad 16-pin small plastic package. The common application circuit is shown in figure 1, and in the driving application, the V of FOD8332OPin (gate drive output voltage pin) via drive resistor RGAnd a voltage booster formed by a discrete NPN and PNP totem pole configuration to increase output drive current, while the DESAT pin (desaturation voltage input pin) of the FOD8332 passes through a 100 omega resistor and a diode DDESATConnected with the collector of IGBT, and connected with V at DESAT pinEA blind area capacitor C is connected between the pins (output power supply voltage)BLANK. However, the current general driving chip mostly adopts a current source type IGBT driver, detects the saturation voltage drop of the current source type IGBT driver, and is arranged in the driverThe partial current source has small current and small external blind area capacitance value, so that the anti-interference performance is poor, and IGBT error protection is easy to occur.
For this, it is necessary to specially design the corresponding anti-interference performance circuit, as shown in fig. 2, first of all, V at FOD8332OA constant current source is led out of the pin, and the output voltage of the Vo pin is 15V and used for sending a driving signal to the gate pole of the IGBT. The driving resistance is RGAt RGOutput terminal and dead zone capacitor CBLANKA constant current source circuit is connected between the two capacitors, and the current of the constant current source is opposite to the blind area capacitor CBLANKAnd charging, namely, adding a constant current source, so that the capacitance value of the blind area capacitor can be increased to be an nF level. Secondly, another capacitor C1 is added into the DESAT pin of the IGBT desaturation voltage input pinBLANK，C1BLANKCapacitance of nF class, C1 BLANK100 omega detection resistors R and CBLANKForming a pi-type capacitance-resistance network.
The spike voltage pulse generated when the IGBT switches is passed through the diode DDESATIs capacitively coupled into the desaturation voltage input pin of the IGBT, resulting in driver mis-protection. The addition of the pi-type resistance-capacitance network can well absorb spike voltage, and prevents the IGBT fault turn-off caused by interference of spike voltage pulses on the IGBT fault detection circuit. When the IGBT has a short-circuit fault, the IGBT enters a desaturation region, the current of the constant current source cannot flow away through the IGBT, the charging time constant is small, the IGBT can be rapidly charged to the threshold voltage, and the fault detection circuit is started at 10 mu s to ensure that the IGBT is not damaged.
Finally, at the DESAT pin and V of the IGBT driverETransient voltage Suppressor (TVS diode) V is incorporated in a pinZFor peak clipping, transient suppression diode VZThe IGBT power supply device is matched with a pi-type resistance-capacitance network for use and is used for absorbing spike voltage generated by a C pole and an E pole in the turn-on and turn-off processes of the IGBT. When the peak voltage exceeds the breakdown voltage of the transient suppression diode, the peak voltage is limited in a voltage range by the transient suppression diode, and the energy of the peak voltage is consumed. In addition to the above three measures for improving the noise immunity, it is also necessary to cooperate with the control logic to better improve the noise immunity.When the FAULT signal of the FAULT pin of the IGBT driver is output and reported to the controller, the controller should shut down other normally working IGBTs in an emergency, or some IGBT turn-on states are reserved according to actual conditions so that the current of the device can smoothly flow through the load, and current mutation is avoided. After the FAULT of the FAULT pin of the driver disappears, the switching logic of the device is changed into a normal state to continue working, so that the reliability is further improved.
Therefore, a method for improving the anti-interference performance of the IGBT driver can be obtained, and as shown in the attached figure 3, the method comprises the following steps:
the method comprises the following steps:
(1): at the gate drive output voltage pin (V) of the IGBT driverOPin) and a desaturation voltage input pin (DESAT pin) of the driver;
(2): at the desaturation voltage input pin (DESAT pin) of the IGBT driver and the output supply voltage pin (V) of the driverEPins) are arranged between the two circuits;
(3): at the desaturation voltage input pin (DESAT pin) of the IGBT driver and the output supply voltage pin (V) of the driverEPin) is provided with a transient suppression diode.
(4): when the FAULT signal of the FAULT pin of the IGBT driver is output and reported to the controller, the controller should emergently close other normally working IGBTs or keep the opening state of part of the IGBTs to enable the current of the device to smoothly flow through the load, so as to avoid current mutation, and after the FAULT of the FAULT pin of the driver disappears, the IGBT switching logic is changed into a normal state to continue working.
The method for setting the external constant current source comprises the following steps: at the output voltage pin (V)OPin) driving resistor RGOutput terminal and dead zone capacitor CBLANKA constant current source is connected between the two capacitors, and the current of the constant current source is opposite to the blind area capacitor CBLANKCharging; the blind area capacitor CBLANKSet at the desaturation voltage input pin (DESAT pin) and the output supply voltage pin (V)EPins).
The method for setting a pi-type RC absorption circuit comprises detecting at desaturation voltage input pin (DESAT pin) of driverOne end of the measuring resistor R is connected with the blind area capacitor CBLANKOne end of the detection resistor R is connected with another capacitor C1BLANKC1BLANKThe other end of the first and second terminals is connected with an output power supply voltage pin (VEPin) from C1BLANKDetecting resistance and CBLANKForming a pi-type RC absorption circuit.
The method for arranging a transient suppression diode is to connect the anode of the transient suppression diode with the output power supply voltage pin (V)EPin), a detection resistor R and a detection diode D of a cathode of the transient suppression diode and a desaturation voltage input pin (DESAT pin)DESATAre connected.
By the method for improving the anti-interference performance, the constant current source is added from the output end of the driver Vo and the fault detection circuit, and the problem of poor anti-interference performance caused by small current of the constant current source in the driver is solved. A pi-type resistance-capacitance absorption circuit is added in the base pin DESAT, the filtering effect of the IGBT fault detection circuit is enhanced, and the filter is combined with the TVS diode, so that the amplitude of peak voltage generated by a C pole and an E pole in the turn-on and turn-off processes of the IGBT is limited, and the energy of the peak voltage is absorbed. The driver is matched with the control logic design of the device, so that the anti-interference performance of the driver is further improved.
There has been described herein only the preferred embodiments of the invention, but it is not intended to limit the scope, applicability or configuration of the invention in any way. Rather, the detailed description of the embodiments is presented to enable any person skilled in the art to make and use the embodiments. It will be understood that various changes and modifications in detail may be effected therein without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (6)
1. A method of improving interference immunity of an IGBT driver, the method comprising the steps of:
(1): at the gate drive output voltage pin (V) of the IGBT driverOPin) and a desaturation voltage input pin (DESAT pin) of the driver;
(2): at the desaturation voltage input pin (DESAT pin) of the IGBT driver and the output supply voltage pin (V) of the driverEPins) are arranged between the two circuits;
(3): at the desaturation voltage input pin (DESAT pin) of the IGBT driver and the output supply voltage pin (V) of the driverEPin) is provided with a transient suppression diode.
(4): when the FAULT signal of the FAULT pin of the IGBT driver is output and reported to the controller, the controller should emergently close other normally working IGBTs or keep the opening state of part of the IGBTs to enable the current of the device to smoothly flow through the load, so as to avoid current mutation, and after the FAULT of the FAULT pin of the driver disappears, the IGBT switching logic is changed into a normal state to continue working.
2. The method for improving the interference resistance of the IGBT driver as claimed in claim 1, wherein the method for providing an external constant current source comprises: at the output voltage pin (V)OPin) driving resistor RGOutput terminal and dead zone capacitor CBLANKA constant current source is connected between the two capacitors, and the current of the constant current source is opposite to the blind area capacitor CBLANKCharging; the blind area capacitor CBLANKSet at the desaturation voltage input pin (DESAT pin) and the output supply voltage pin (V)EPins).
3. The method of claim 1, wherein the arrangement of the pi-type RC absorption circuit is such that a dead zone capacitor C is connected to an end of a detection resistor R of a desaturation voltage input pin (DESAT pin) of the driverBLANKOne end of the detection resistor R is connected with another capacitor C1BLANKC1BLANKThe other end of the first and second terminals is connected with an output power supply voltage pin (VEPin) from C1BLANKDetecting resistance and CBLANKForming a pi-type RC absorption circuit.
4. The method of claim 1, wherein the step of providing a transient suppression diode comprises connecting an anode of the transient suppression diode to the output supply voltage pin (V)EPin), of transient suppression diodesDetection resistor R and detection diode D of cathode and desaturation voltage input pin (DESAT pin)DESATAre connected.
5. The method for improving the interference resistance of the IGBT driver as claimed in claim 1, wherein the C1BLANKThe capacitance value is of nF order.
6. A method of improving the immunity of an IGBT driver to interference as claimed in any one of claims 1 to 5, said driver being FOD 8332.
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| CN201811507254.7A CN111313881B (en) | 2018-12-11 | 2018-12-11 | Method for improving anti-interference performance of IGBT driver |
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| CN201811507254.7A CN111313881B (en) | 2018-12-11 | 2018-12-11 | Method for improving anti-interference performance of IGBT driver |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN114421941A (en) * | 2022-01-19 | 2022-04-29 | 赛晶亚太半导体科技(浙江)有限公司 | IGBT grid digital driving system |
| CN115149939A (en) * | 2022-09-01 | 2022-10-04 | 清华大学 | Discrete high-voltage electronic device and method |
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Cited By (3)
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| CN114421941A (en) * | 2022-01-19 | 2022-04-29 | 赛晶亚太半导体科技(浙江)有限公司 | IGBT grid digital driving system |
| CN115149939A (en) * | 2022-09-01 | 2022-10-04 | 清华大学 | Discrete high-voltage electronic device and method |
| CN115149939B (en) * | 2022-09-01 | 2023-01-06 | 清华大学 | Discrete high-voltage electronic device and method |
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