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   Abstract: The SCALE actuation is the IGBT intellectualization actuation board which Swiss Concept Corporation produces, may use in actuating and protecting IGBT. In the article introduced this IGBT intellectualization actuation board’s major function, the working pattern and the pin function, give this component’s model application electric circuit.

    Key word: IGBT; Actuation module; SCALE

1 outline

Because IGBT (insulation grid bipolarity transistor) is one kind of voltage control power component, it must the driver power to be young, the control circuit is simple, the breakover pressure drop is low, and has the big clear working place and short circuit bearing capacity. Therefore, IGBT in the power above electric power electron system (for example frequency changer, the UPS power source, high frequency welding machine and so on) has substituted for POWER MOSFET and POWER BJT gradually at present becomes in the power on-off element market important. However 熑 coils mediates line of у She Dong and protects IGBT to become one in present electric power electron domain important research subjects. Not only has the protection function driving circuit to be able under the normal work condition the driver power which provides to IGBT needs, can play under exceptionally the active status protects IGBT the role, moreover must be able to enable in electric power electron system’s IGBT to have the very good replace characteristic. Therefore 煾 si reads nai that to move the electric circuit is improves the electronic products quality and the reliability, thus strengthens one of its competitive power keys. This article introduces one kind of high performance, intellectualized IGBT actuation board SCALE.

Figure 1

2 function introductions

The SCALE actuation board series is Swiss Concept Corporation produces, Concept Corporation is the specialized production IGBT driving circuit’s company, mainly module forms a complete set for Simens /EUPEC the high-pressured big electric current IGBT. This SCALE actuation board uses the ASIC design, only uses the 15V power source to actuate, the turn-on frequency may be bigger than 100kHz, and has high reliable and the long life characteristic, may actuate 1700V, 1200A IGBT. 1998 year won the ABB outstanding electric power electron project title, its main model and driving force like table 1 arranged in order.

Table 1 SCALE main model and driving force

2.1 SCALE characteristics

* the practical scope wide 熆 takes Tau the fan to joke the kilowatt to several megawatt power ranges and in the practical pressure resistance request scope, may work nearly in all frequencies and the modulation pattern, is suitable in any factory module.

* the volume is exquisite, the structure is compact, the application is flexible, has direct and half bridge pattern may supply the choice. Under half bridge pattern, may select the dead time which requests.

* the cost is low, has the very high performance/price ratio. Besides may provide the electronics grid to actuate, but also has examination functions and so on condition demonstration and power source isolation, is one kind may satisfy market all requests, the most economical practical actuation board.

* the use is simple. This actuation board’s electrical interface is simple, may process the 5~15V level the standard logical signal. Has the Schmitt trigger input characteristic, and does not have the special request to the input signal. The breakdown transmission use collecting electrode leads the way the output, may with the commonly used logic level compatible. Because the actuation board has all intellectualized actuation function, and the driving signal, the condition transmission and the power source and the power part isolate completely, therefore the use is simple. In the majority situations, actuates the standard IGBT module with the intellectualized SCALE actuation board, (IPM) is simpler than the use intellectualization IGBT module, is also more nimble.

2.2 SCALE major functions

SCALE by electronic connection LDI, the intelligent electronics grid actuates IGD and 15V the DC/DC power source is composed, its principle block diagram as shown in Figure 1. The figure shows, this actuation board mainly has two function blocks. And function block #1 is LDI (between logical and actuation connection), each LDI may actuate two groups. Adds in input end’s PWM signal again after the pulse transformer isolation, then outputs the driving signal, actuates the IGBT work.

Function block #2 is IGD (intelligent electronics grid actuation), when this function block work, each Lu Yong IGD from the pulse transformer receive coded pulse anticlutter system signal, then decodes the primitive PWM signal. Passes through the power amplifier again, then may give the IGBT electronics grid to provide several ampere drive currents.

(1) electronic connection LDI001

Because the PWM signal’s frequency and the dutyfactor change are big, therefore cannot simply through the transformer transmission. Therefore, SCALE provided the LDI001 logic actuation connection, LDI001 structure as shown in Figure 2, it had the following function:

* may provide a simple connection for the user, two signal input ends have the Schmitt trigger characteristic;

* with 5V, the 15V logic level matches.

* has the dead time which half bridge needs;

* carries on the code to the PWM signal, causes its to be possible through the pulse transformer transmission;

* the recognition code transmission’s condition announcing signal and enlarges, the thinking user provides a quasistatic the status signal.

Figure 2

    The SCALE driver may not add any part, but is directly connected with the logic circuit, may also pass the long electric cable to be connected. In this kind of situation, to obtain the high letter to be hot-tempered the ratio, should use the 15V level. Simultaneously should obtain the dead time which through the external connection RC network requests.

(2) actuates block IGD001

IGD001 has all essential intelligent actuation function, like transformer connection, overload and short circuit protection, locking time logic, condition notice, to supply voltage and output stage monitor and so on.

IGD actuation block’s internal structure diagram as shown in Figure 3, this actuation block mainly uses in completing the following function:

* to the coded signal which receives from the pulse transformer carries on the decoding;

* actuates IGBT with the power amplifier PWM signal;

* monitors IGBT the overload and the short circuit;

* monitor undervoltage;

* has the response time and the locking time;

* (LDI001) sends out the condition announcing signal for the controller.

Intelligent actuation block IGD001 all protections, the monitor function (for example overflow, short circuit protection and undervoltage protection) put in secondarily. Thus, when presents the breakdown, the electric circuit will immediately be shut down and locks.

Figure 3

    (3) SCALE actuation block protection function

The SCALE protection mainly includes the short circuit and the overflow as well as the power source monitor. Regarding the short circuit and the overflow protection, in SCALE actuation each group have a Vce observation circuit. Rth is the shutdown threshold value reference resistance. After a IGBT clear’s section of response time, the Vce observation circuit does not have an effect. After but when Vce presents the breakdown, the locking time function starts to start, and causes the driver in the locking time to lock IGBT, but no longer accepts the input signal. In module each group has own fixed function, and realizes by each road’s LGD001. Once Vce surpasses by the Rth hypothesis threshold value, locking will start immediately.

In SCALE each group has an undervoltage observation circuit. When the supply voltage drops to 10V or 11V, IGBT will carry out the negative pressure to shut off and to carry on the malfunction alert.

3 SCALE prime task patterns

3.1 direct patterns

Under the direct pattern, each group IGBT will work independently. This pattern may use in having the dead time PWM signal actuation, may also use in the independent working each group IGBT. The MOD input and V connected, RC1 and the RC2 earth, is the direct pattern. Under the direct pattern, the condition outputs SO1 and SO2 returns separately, when therefore presents the breakdown, may conveniently determine the breakdown appears in that group.

3.2 half bridge patterns

Through network may obtain several hundred nanosecond dead times with RC1 and RC2 the connected RC. When input end B is the low level, two group IGBT is shut both off. The MOD input earth is half bridge pattern, inputs IA is the PWM input, IB is enables the input. Joins the 4.7V zener diode in the VL/R input end to be possible to cause input end IA and IB establishes in the TTL level. Because under this pattern’s condition outputs SO1 and SO2 connects in together, therefore, two groups breakdowns are “or” relations. When the RC network is 10kΩ/100pF, the dead time is 500s.

4 pin functions

Presently take in SCALE 2SD315A as an example, gave this module the pin function, Figure 4 has given the 2SD315A pin distribution map.

    4.1 input section pin function

GND: Power source place;

VDC: Power source 15V, for DC/DC power source use;

VDD: Power source 15V, uses for LDI001;

VL/R: Uses for to establish input end InA and the InB Schmitt trigger’s switch threshold value. When input signal for Canada when VL/R terminal voltage’s 2/3, clear; For 1/3 when shuts off;

MOD: Pattern choice;

INA: Signal input end A;

INB: Signal input end B;

SO1: The condition outputs 1;

SO2: The condition outputs 2;

RC1: Produces #1 the road dead time RC network;

RC2: Produces #2 the road dead time RC network;

RC end: Establishment dead time RC network.

In half bridge pattern, looks carefully the connection the RC network with each RC to be possible to determine that corresponds each road’s dead time. The dead time possibly has the very small drifting along with the temperature. Meets the resistance not to permit is smaller than 5kΩ. The RC network must according to the chart connection, and the resistance and the VCC connection, the capacity ground. Table 2 have given the RC network and the dead time corresponding relationships.

Table 2 RC networks and dead time

4.2 output unit pin function

G end (electronics grid): Is connected with the IGBT electronics grid, and actuates with 15V.

E end (emitter electrode): With the IGBT emitter electrode direct connected, and the segment should as far as possible short.

C end (collecting electrode): Uses for examines when the clear the IGBT loss of voltage, therefore 煴 the small box shin benzene blesses advanced in age Sang Qian to gather together the electrode to be approximately connected. Regarding 1200V and the 1300V module, applies 2 or 3 1N4007 diodes satisfies 140% pressure resistance request. Uses the ordinary high-voltage diode then, generally cannot restore the diode quickly with the high pressure.

Rth end (reference resistance): Through meets may determine IGBT in the Rth end reference resistance the protection shutdown threshold value. The E end’s reference potential, the reference resistance must approach the IGBT module as far as possible. When the C end’s voltage surpasses the Rth end the voltage, will start the IGBT protection function. This time the current supply will provide 150μA electric current.

The reference resistance value may calculate through the following formula:

Rth=Vth/150μA

If Vth is time 5.85V, Rth should choose 39 kΩ resistances.

5 concluding remark

Intellectualized IGBT actuation board SCALE has the driving force to be strong, the reliability high, has characteristics and so on many kinds of protection functions, not only it can provide the driver power which under the normal work condition to IGBT needs; Moreover may protect IGBT under exceptionally the active status, meanwhile can enable in electric power electron system’s IGBT to have the very good replace characteristic. Therefore, use high performance’s actuation circuit wafer SCALE is improves the electronic products quality and the reliability, thus strengthens one of its competitive power keys.