EPE Association: EPE 1993 - 44 - Dialogue Session DS3.2: DEVICES: IGBT CIRCUITS, MCT's

EPE 1993 - 44 - Dialogue Session DS3.2: DEVICES: IGBT CIRCUITS, MCT's
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 1993 - Conference > EPE 1993 - 44 - Dialogue Session DS3.2: DEVICES: IGBT CIRCUITS, MCT's

   [return to parent folder]

   COMPARISON OF THREE IGBT-INVERTERS, ONE HARD-SWITCHED AND TWO WITH SNUBBER CIRCUITS USING A MINIMUM NUMBER OF COMPONENTS
By M. A. E. Andersen [View]
[Download]

Abstract: This paper describes a comparison of a hard-switched lGBT-inverter and a symmetrical and an asymmetrical snubber circuit for IGBT-inverters using a minimum number of components. The two snubber circuits are optimally designed and they are compared to the hard-switched inverter with respect to switching times, switching energy losses in the IGBT and to the snubber circuit and the maximum switching frequency obtainable. ln this way some guide-lines for using hard-switching and the two different snubber circuits are given.

   THE SWITCHING BEHAVIOUR OF AN IGBT IN ZERO CURRENT SWITCH MODE
By S. Huth; S. Winternheimer [View]
[Download]

Abstract: The IGBT is a useful device for resonant applications. Because of its bipolar conduction mode and its ability of blocking a reverse voltage it seems to be well suited to the zero current switching. Measurements in a quasi resonant configuration which works in a full wave mode show, that the switching losses are dependent on the time between the begin of current oscillation and the moment the IGBT is turned off. These losses are at a minimum when the channel of the IGBT is opened as long as possible. For the half wave mode it is shown that the stationary reverse blocking capability of a non-punch-through-IGBT can be improved by turning on the MOSFET-channel with a positive gate-source-voltage.

   OPTIMIZATION OF THE TURN-OFF PERFORMANCE OF IGBT AT OVERCURRENT AND SHORT-CIRCUIT CURRENT
By H.-G. Eckel; L. Sack [View]
[Download]

Abstract: The maximum safe collector current of an lnsulated-Gate-Bipolar Transistor is limited by the junction temperature and the overvoltage due to the parasitic inductance at turn-off. In applications, which require a high utilization of the rated collector-emitter breakdown voltage of the IGBT, the gate control has to ensure low loss turn-off at nominal current and low overvoltage turn-off at overcurrent and short-circuit current. A two-stage gate control for the IGBT is presented, which allows a reduction of the overvoltage at overcurrent turn-off without increasing the switching losses at nominal current. A further reduction of the overvoltage is achieved by a current dependent change over of the gate resistance. The measure of the current is the miller-plateau of the gate-emitter voltage. The experimental results prove, that it is possible to achieve a considerable reduction of the overvoltage at overcurrent and short-circuit current.

   INVESTIGATION ON IGBT SWITCHING PROCESS WITH VARIABLE GATE CHARGE CURRENT
By L. Abraham; G. Bramm; M. Reddig [View]
[Download]

Abstract: Turn on and turn off switching characteristic of an IGBT can be widely influenced by the shape of gate current. The paper treats measurements of switching behaviour with extremly high gate charging currents at turn on and turn off for inductive load with free wheeling diode. The gate drive for high slew rates must be designed in respect of HF rules, and the commutation circuit should be laid out with very low inductance. The test circuits are described. The measurements are demonstrated and compared with computer simulations developed elsewhere /1/.

   THE INSULATED GATE BIPOLAR TRANSISTOR RESPONSE IN DIFFERENT SHORT CIRCUIT SITUATIONS
By T. Nilsson [View]
[Download]

Abstract: This paper presents a study of commercially available Insulated Gate Bipolar Transistors (IGBT) when subjected to extreme stress. The purpose is to achieve an improved understanding of the consequences of different types of short-circuit situations. It is evident that different types of short-circuits will stress the IGBT in different ways. This is vital information for the design of short-circuit proof converters using the IGBT. Such a design will require both understanding of the underlying physical mechanisms and adequate testing procedures for the IGBT. To ensure safe operation of these transistors in different short-circuit situations, at least results from the following safe operatinq area measurements sbould be included in the data sheets. Firstly a measurement stating the combinations of current, voltage and temperature, which the IGBT can handle at turn-off from full conduction and extreme current levels. Secondly a measurement stating the combinations of temperature and load which the IGBT can handle at simultaneously high voltage and current.

   CURRENT MEASUREMENT USING SWITCH VOLTAGE DROP IN IGBT DC CIRCUIT BREAKER APPLICATION
By X. Tian; R. Moussanet [View]
[Download]

Abstract: Electrical systems using solid-state devices and controlled by computer have more and more being developed. The new architecture opens up new possibilities of measuring current. In static DC circuit breaker, the current measurement can be easier carried out by means of switch voltage drop than other classical methods. This paper describes the design and the test results of this current measuring principle in an IGBT DC circuit breaker. A computer along with an analogue circuit is used to estimate the IGBT junction temperature, to compensate the IGBT on-state characteristic drift, and then to compute the current from the voltage drop measurement. It is shown that such a design gives a good measure precision in the current range of static circuit breaker applications.

   On the selection of IGBT devices in Soft-Switching applications
By A. Consoli; C. Licitra; S. Musumeci; A. Testa; F. Frisina; R. Letor [View]
[Download]

Abstract: The purpose of the present paper is to give a support to designers of resonant circuits in selecting the more appropriate IGBT devices to be used on the basis of the design requirements. A new method to characterize IGBT devices in resonant circuits has been developed and used to obtain diagrams giving IGBT power losses with the main parameters related to resonant topology, output requirements and resonant link features.

   ANALYSIS AND COMPARISON OF A NEW PASSIVE LOSSLESS SNUBBER FOR HIGH FREQUENCY CONVERTER APPLICATION
By X. He; B.W. Williams; S. J. Finney; T. C. Green [View]
[Download]

Abstract: Two variations of a new adaptive turn on/off snubber configuration are developed where energy trapped in the snubber is fully recovered, passively, into the DC rail, in addition to the load, without any active devices or resistors. The circuit may be operated in a soft-clamped, or hard-clamped snubber mode. The circuit models are analyzed in detail and their relative circuit performances are compared. Besides individual advantages, the two variations of the snubber posses the common characteristics that maximum over-shoot voltage on the switch is fixed, peak switch current is low and the operational range of load current is wider than conventional snubbers. The application of the two variations of the snubber, for use in high frequency power converters, is discussed and design equations are given, along with simulations and experimental results for an IGBT converter.

   EXPERIMENTAL RESULTS USING MCTS IN HARD AND SOFT SWITCHING MODES
By F.-F. Protiwa; E. Seekamp [View]
[Download]

Abstract: The huge advances in power electronics during the last decade are mainly due to the revolution in semiconductor technology. New power switching devices - like e.g. the IGBT - emerged in recent years making the task for system designers much easier. But the search for even better power electronic switches still goes on. One of the most promising attempts is the MCT, the MOS controlled thyristor. lts principal operation mode is based on the internal thyristor structure combined with MOS technology. The main advantage of the MCT lies in its extremely low on-state voltage and its ease of control. This paper presents practical experience using a p-type MCT. The investigations focus on the dynamic and static characteristics including a comparison of the behaviour in the hard and soft switching modes. Limitations to the switching frequency, short circuit behaviour and driving requirements are covered, too.

EPE 1993 - 44 - Dialogue Session DS3.2: DEVICES: IGBT CIRCUITS, MCT's
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 1993 - Conference > EPE 1993 - 44 - Dialogue Session DS3.2: DEVICES: IGBT CIRCUITS, MCT's
	[return to parent folder]

	COMPARISON OF THREE IGBT-INVERTERS, ONE HARD-SWITCHED AND TWO WITH SNUBBER CIRCUITS USING A MINIMUM NUMBER OF COMPONENTS By M. A. E. Andersen	[View] [Download]
Abstract: This paper describes a comparison of a hard-switched lGBT-inverter and a symmetrical and an asymmetrical snubber circuit for IGBT-inverters using a minimum number of components. The two snubber circuits are optimally designed and they are compared to the hard-switched inverter with respect to switching times, switching energy losses in the IGBT and to the snubber circuit and the maximum switching frequency obtainable. ln this way some guide-lines for using hard-switching and the two different snubber circuits are given.

	THE SWITCHING BEHAVIOUR OF AN IGBT IN ZERO CURRENT SWITCH MODE By S. Huth; S. Winternheimer	[View] [Download]
Abstract: The IGBT is a useful device for resonant applications. Because of its bipolar conduction mode and its ability of blocking a reverse voltage it seems to be well suited to the zero current switching. Measurements in a quasi resonant configuration which works in a full wave mode show, that the switching losses are dependent on the time between the begin of current oscillation and the moment the IGBT is turned off. These losses are at a minimum when the channel of the IGBT is opened as long as possible. For the half wave mode it is shown that the stationary reverse blocking capability of a non-punch-through-IGBT can be improved by turning on the MOSFET-channel with a positive gate-source-voltage.

	OPTIMIZATION OF THE TURN-OFF PERFORMANCE OF IGBT AT OVERCURRENT AND SHORT-CIRCUIT CURRENT By H.-G. Eckel; L. Sack	[View] [Download]
Abstract: The maximum safe collector current of an lnsulated-Gate-Bipolar Transistor is limited by the junction temperature and the overvoltage due to the parasitic inductance at turn-off. In applications, which require a high utilization of the rated collector-emitter breakdown voltage of the IGBT, the gate control has to ensure low loss turn-off at nominal current and low overvoltage turn-off at overcurrent and short-circuit current. A two-stage gate control for the IGBT is presented, which allows a reduction of the overvoltage at overcurrent turn-off without increasing the switching losses at nominal current. A further reduction of the overvoltage is achieved by a current dependent change over of the gate resistance. The measure of the current is the miller-plateau of the gate-emitter voltage. The experimental results prove, that it is possible to achieve a considerable reduction of the overvoltage at overcurrent and short-circuit current.

	INVESTIGATION ON IGBT SWITCHING PROCESS WITH VARIABLE GATE CHARGE CURRENT By L. Abraham; G. Bramm; M. Reddig	[View] [Download]
Abstract: Turn on and turn off switching characteristic of an IGBT can be widely influenced by the shape of gate current. The paper treats measurements of switching behaviour with extremly high gate charging currents at turn on and turn off for inductive load with free wheeling diode. The gate drive for high slew rates must be designed in respect of HF rules, and the commutation circuit should be laid out with very low inductance. The test circuits are described. The measurements are demonstrated and compared with computer simulations developed elsewhere /1/.

	THE INSULATED GATE BIPOLAR TRANSISTOR RESPONSE IN DIFFERENT SHORT CIRCUIT SITUATIONS By T. Nilsson	[View] [Download]
Abstract: This paper presents a study of commercially available Insulated Gate Bipolar Transistors (IGBT) when subjected to extreme stress. The purpose is to achieve an improved understanding of the consequences of different types of short-circuit situations. It is evident that different types of short-circuits will stress the IGBT in different ways. This is vital information for the design of short-circuit proof converters using the IGBT. Such a design will require both understanding of the underlying physical mechanisms and adequate testing procedures for the IGBT. To ensure safe operation of these transistors in different short-circuit situations, at least results from the following safe operatinq area measurements sbould be included in the data sheets. Firstly a measurement stating the combinations of current, voltage and temperature, which the IGBT can handle at turn-off from full conduction and extreme current levels. Secondly a measurement stating the combinations of temperature and load which the IGBT can handle at simultaneously high voltage and current.

	CURRENT MEASUREMENT USING SWITCH VOLTAGE DROP IN IGBT DC CIRCUIT BREAKER APPLICATION By X. Tian; R. Moussanet	[View] [Download]
Abstract: Electrical systems using solid-state devices and controlled by computer have more and more being developed. The new architecture opens up new possibilities of measuring current. In static DC circuit breaker, the current measurement can be easier carried out by means of switch voltage drop than other classical methods. This paper describes the design and the test results of this current measuring principle in an IGBT DC circuit breaker. A computer along with an analogue circuit is used to estimate the IGBT junction temperature, to compensate the IGBT on-state characteristic drift, and then to compute the current from the voltage drop measurement. It is shown that such a design gives a good measure precision in the current range of static circuit breaker applications.

	On the selection of IGBT devices in Soft-Switching applications By A. Consoli; C. Licitra; S. Musumeci; A. Testa; F. Frisina; R. Letor	[View] [Download]
Abstract: The purpose of the present paper is to give a support to designers of resonant circuits in selecting the more appropriate IGBT devices to be used on the basis of the design requirements. A new method to characterize IGBT devices in resonant circuits has been developed and used to obtain diagrams giving IGBT power losses with the main parameters related to resonant topology, output requirements and resonant link features.

	ANALYSIS AND COMPARISON OF A NEW PASSIVE LOSSLESS SNUBBER FOR HIGH FREQUENCY CONVERTER APPLICATION By X. He; B.W. Williams; S. J. Finney; T. C. Green	[View] [Download]
Abstract: Two variations of a new adaptive turn on/off snubber configuration are developed where energy trapped in the snubber is fully recovered, passively, into the DC rail, in addition to the load, without any active devices or resistors. The circuit may be operated in a soft-clamped, or hard-clamped snubber mode. The circuit models are analyzed in detail and their relative circuit performances are compared. Besides individual advantages, the two variations of the snubber posses the common characteristics that maximum over-shoot voltage on the switch is fixed, peak switch current is low and the operational range of load current is wider than conventional snubbers. The application of the two variations of the snubber, for use in high frequency power converters, is discussed and design equations are given, along with simulations and experimental results for an IGBT converter.

	EXPERIMENTAL RESULTS USING MCTS IN HARD AND SOFT SWITCHING MODES By F.-F. Protiwa; E. Seekamp	[View] [Download]
Abstract: The huge advances in power electronics during the last decade are mainly due to the revolution in semiconductor technology. New power switching devices - like e.g. the IGBT - emerged in recent years making the task for system designers much easier. But the search for even better power electronic switches still goes on. One of the most promising attempts is the MCT, the MOS controlled thyristor. lts principal operation mode is based on the internal thyristor structure combined with MOS technology. The main advantage of the MCT lies in its extremely low on-state voltage and its ease of control. This paper presents practical experience using a p-type MCT. The investigations focus on the dynamic and static characteristics including a comparison of the behaviour in the hard and soft switching modes. Limitations to the switching frequency, short circuit behaviour and driving requirements are covered, too.