EPE Association: EPE 1985 - 03 - Lecture Session 1.03: GTO AND RCT CONVERTERS

EPE 1985 - 03 - Lecture Session 1.03: GTO AND RCT CONVERTERS
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 1985 - Conference > EPE 1985 - 03 - Lecture Session 1.03: GTO AND RCT CONVERTERS

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   CHARACTERISTICS OF A NEW PWM-CONTROLLED GTO THREE-PHASE CONVERTER
By P. Viriya; H. Kubota; K. Matsuse [View]
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Abstract: In this paper, the characteristics of a New PWM-controlled GTO Three-Phase Converter are described. An auxiliary circuit consisting of GTO thyristors is newly developed to treat the commutating energy generated in ac source leakage reactance during circuit commutation so as to maintain high efficiency. Various characteristics of the auxiliary circuit, snubber capacitor and the new converter circuit are investigated. The harmonic distribution curves from this PWM-Controlled method over a wide control range of modulation factor are calculated and compared with conventional ones. The new converter investigated in this paper has high efficiency and low harmonic content. An auxiliary capacitor makes the snubber capacitor smaller and its voltage is also used to limit voltage spikes generated in the ac source by controlling the conducting state of the GTO's in the auxiliary circuit.

   A SINGLE GTO RESONANT DC-DC CONVERTER
By J. P. Ferrieux; R. Feuillet; H. Le Huy; E. Toutain [View]
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Abstract: This paper presents a resonant dc-dc converter in which a single GTO thyristor is used as power switch. The operation of GTO thyristors is considered and the choice of these devices for use in resonant converters is explained and justified. In the presented converter, a single inductive element is used. Steady state operation is studied with the aid of a simulation program. Design considerations and experimental results are given.

   APPLICATION OF GATE TURN-OFF THYRISTORS (GTO) - CONCEPTS AND PROBLEMS TODAY
By M. Peppel; Th. Salzmann; A. Schönherr [View]
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Abstract: Self-commutated converters can be considerably simplified and improved by the use of turnoff thyristors (GTO's). In order to exploit the advantages of the GTO's in practica, concepts concerning their gating, circuitry and protection are required which take their special requirements into account. The gating requirements of a GTO thyristor are described, as is a modular gating unit with integrated protective functions which fulfills all the requirements and operates the GTO optimally under all conditions. To ensure safe operating conditions, particular circuits are required which reduce switching losses in the GTO. However, the energy converted in the resistors of conventional switching aid networks raises the total losses of a GTO equipment considerably. An auxiliary circuit for an inverter is described by means of which a large proportion of this energy can be fed back into the dc-link with only minor design and operational limitations. At present the fault-protection of the GTO's has usually more influence on their dimensioning than the operational demands. On the other hand a high level of protection should be realized with little additional circuit complexity and nevertheless a good use of the GTO capacity. The GTO inverter protection system presented here takes these partially contradictory demands into account.

   SWITCHING CHARACTERISTICS OF HIGH POWER GATE TURN-OFF THYRISTORS
By F. Fasce; M. Zambelli [View]
[Download]

Abstract: High power GTOs are now entering the European market of power conversion. Even if these devices have been available for many years from Japanese manufacturers there is little standardization in their characterization. This is particularly important as far as the switching characteristics are concerned. This paper tries to outline a possible set of data for switching and on-state characteristics and to explain some important details in the related waveforms.

   PARALLEL AND SERIE CONNECTION OF GTOs IN TRACTION APPLICATIONS
By B. Detemmerman [View]
[Download]

Abstract: In the actual state of development of GTOs, it is sometimes necessary to parallel or serie connect these semiconductors when they handle high currents or withstand high voltages, particularly for propulsion or supply of auxiliaries in traction applications on urban network (600 and 750 Vdc) or railway netvork (3 kV). Classical methods well experienced with thyristors are not always satisfying because of wide spread of characteristics of GTOs. Usual or orginal technics for parallel and serie connections of these new components are reviewed in this paper in the case of choppers and inverters for motorization (250 kW to 600 KVA), or for choppers and converters supplying traction auxiliaries from 3 kV railway network. In these applications measurements of characteristics of GTOs are often necessary in order to connect those which have a similar behaviour, and great care has to be taken with the achievement and wiring of gate drivers.

   FAST-SWITCHING REVERSE CONDUCTING THYRISTORS IMPROVE PERFORMANCE OF HIGH POWER SERIES RESONANT CIRCUITS
By H. Renggli; J. L. Steiner; J. Vitins [View]
[Download]

Abstract: The advantages of short turn-off time, high blocking voltage, simple gate drive requirements and the benefit of integration of thyristor and antiparallel diode together give the reverse conducting thyristor substantial merit in industrial high power series resonant circuits with switching frequencies up to 50kHz. Guidelines are given for the design of the snubber and protection circuits which permit safe operation in power supplies with high internal switching frequency and resonant inverters for induction heating in the range P>=1 kW. Higher power levels >= 100 kW are readily obtained by operating at high voltages of several kV in the same circuits with devices connected in series.

EPE 1985 - 03 - Lecture Session 1.03: GTO AND RCT CONVERTERS
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 1985 - Conference > EPE 1985 - 03 - Lecture Session 1.03: GTO AND RCT CONVERTERS
	[return to parent folder]

	CHARACTERISTICS OF A NEW PWM-CONTROLLED GTO THREE-PHASE CONVERTER By P. Viriya; H. Kubota; K. Matsuse	[View] [Download]
Abstract: In this paper, the characteristics of a New PWM-controlled GTO Three-Phase Converter are described. An auxiliary circuit consisting of GTO thyristors is newly developed to treat the commutating energy generated in ac source leakage reactance during circuit commutation so as to maintain high efficiency. Various characteristics of the auxiliary circuit, snubber capacitor and the new converter circuit are investigated. The harmonic distribution curves from this PWM-Controlled method over a wide control range of modulation factor are calculated and compared with conventional ones. The new converter investigated in this paper has high efficiency and low harmonic content. An auxiliary capacitor makes the snubber capacitor smaller and its voltage is also used to limit voltage spikes generated in the ac source by controlling the conducting state of the GTO's in the auxiliary circuit.

	A SINGLE GTO RESONANT DC-DC CONVERTER By J. P. Ferrieux; R. Feuillet; H. Le Huy; E. Toutain	[View] [Download]
Abstract: This paper presents a resonant dc-dc converter in which a single GTO thyristor is used as power switch. The operation of GTO thyristors is considered and the choice of these devices for use in resonant converters is explained and justified. In the presented converter, a single inductive element is used. Steady state operation is studied with the aid of a simulation program. Design considerations and experimental results are given.

	APPLICATION OF GATE TURN-OFF THYRISTORS (GTO) - CONCEPTS AND PROBLEMS TODAY By M. Peppel; Th. Salzmann; A. Schönherr	[View] [Download]
Abstract: Self-commutated converters can be considerably simplified and improved by the use of turnoff thyristors (GTO's). In order to exploit the advantages of the GTO's in practica, concepts concerning their gating, circuitry and protection are required which take their special requirements into account. The gating requirements of a GTO thyristor are described, as is a modular gating unit with integrated protective functions which fulfills all the requirements and operates the GTO optimally under all conditions. To ensure safe operating conditions, particular circuits are required which reduce switching losses in the GTO. However, the energy converted in the resistors of conventional switching aid networks raises the total losses of a GTO equipment considerably. An auxiliary circuit for an inverter is described by means of which a large proportion of this energy can be fed back into the dc-link with only minor design and operational limitations. At present the fault-protection of the GTO's has usually more influence on their dimensioning than the operational demands. On the other hand a high level of protection should be realized with little additional circuit complexity and nevertheless a good use of the GTO capacity. The GTO inverter protection system presented here takes these partially contradictory demands into account.

	SWITCHING CHARACTERISTICS OF HIGH POWER GATE TURN-OFF THYRISTORS By F. Fasce; M. Zambelli	[View] [Download]
Abstract: High power GTOs are now entering the European market of power conversion. Even if these devices have been available for many years from Japanese manufacturers there is little standardization in their characterization. This is particularly important as far as the switching characteristics are concerned. This paper tries to outline a possible set of data for switching and on-state characteristics and to explain some important details in the related waveforms.

	PARALLEL AND SERIE CONNECTION OF GTOs IN TRACTION APPLICATIONS By B. Detemmerman	[View] [Download]
Abstract: In the actual state of development of GTOs, it is sometimes necessary to parallel or serie connect these semiconductors when they handle high currents or withstand high voltages, particularly for propulsion or supply of auxiliaries in traction applications on urban network (600 and 750 Vdc) or railway netvork (3 kV). Classical methods well experienced with thyristors are not always satisfying because of wide spread of characteristics of GTOs. Usual or orginal technics for parallel and serie connections of these new components are reviewed in this paper in the case of choppers and inverters for motorization (250 kW to 600 KVA), or for choppers and converters supplying traction auxiliaries from 3 kV railway network. In these applications measurements of characteristics of GTOs are often necessary in order to connect those which have a similar behaviour, and great care has to be taken with the achievement and wiring of gate drivers.

	FAST-SWITCHING REVERSE CONDUCTING THYRISTORS IMPROVE PERFORMANCE OF HIGH POWER SERIES RESONANT CIRCUITS By H. Renggli; J. L. Steiner; J. Vitins	[View] [Download]
Abstract: The advantages of short turn-off time, high blocking voltage, simple gate drive requirements and the benefit of integration of thyristor and antiparallel diode together give the reverse conducting thyristor substantial merit in industrial high power series resonant circuits with switching frequencies up to 50kHz. Guidelines are given for the design of the snubber and protection circuits which permit safe operation in power supplies with high internal switching frequency and resonant inverters for induction heating in the range P>=1 kW. Higher power levels >= 100 kW are readily obtained by operating at high voltages of several kV in the same circuits with devices connected in series.