Control device for controlling a power semiconductor component and method for controlling a power semiconductor component

Abstract

A control device for controlling a power semiconductor component which includes at least two voltage-controlled power semiconductor devices which are electrically connected in parallel and which have each a control connection is disclosed. The control device includes a driver element which can be used to set electrical voltages at the control connections of the power semiconductor devices. The control device includes a measuring unit configured to capture electrical currents which flow through the power semiconductor devices. The driver element is configured to set a level and/or a temporal profile of the electrical voltages on the basis of the electrical currents.

Claims

1. A control device for controlling a power semiconductor component having at least two voltage-controlled power semiconductor component parts which are electrically connected in parallel and which each have a control connection, said control device comprising: a measuring unit configured to detect electric currents flowing through the power semiconductor component parts; and a driver element configured to set electrical voltages at the control connections of the power semiconductor component parts, to set an amount and/or a time curve of the electrical voltages as a function of the electric currents, to set a temporal change in the electrical voltages applied at the control connections by adjusting a slope of straight edges of the electrical voltages when the power semiconductor component parts are switched on and/or switched off as a function of the electric currents, to set the electrical voltages on the basis of voltages set during a preceding operation of the power semiconductor component, wherein the electrical currents, which flow through the power semiconductor component parts with specific settings with respect to the electrical voltages, are stored, and to determine the temporal change in the electrical voltages on the basis of the preceding settings.

2. The control device of claim 1, wherein the driver element is configured to set the electrical voltages such that the electric currents are essentially the same.

3. The control device of claim 1, wherein the driver element is configured to set start times and an end time, between which the electrical voltages are applied to the control connections, as a function of the electric currents.

4. The control device of claim 1, wherein the driver element includes an output and an input for each of the power semiconductor component parts for receiving measured values which describe the electric currents.

5. The control device of claim 1, further comprising a further said driver element, with the driver elements operably connected to the power semiconductor component parts in one-to-one correspondence, with the driver elements having each an output connected to the power semiconductor component parts, respectively.

6. The control device of claim 5, wherein the driver elements have each an input for receiving measured values which describe the electric currents through the power semiconductor component parts, and further comprising a communication unit configured to transmit the measured values between the driver elements.

7. The control device of claim 5, further comprising: a central computing unit configured to receive measured values which describe the electric currents; and a communication unit configured to transmit the measured values to the driver elements.

8. A power semiconductor component, comprising: at least two voltage-controlled power semiconductor component parts which are electrically connected in parallel and which each have a control connection; and a control device for controlling the at least two voltage-controlled power semiconductor component parts, said control device comprising a measuring unit configured to detect electric currents flowing through the power semiconductor component parts, and a driver element configured to set electrical voltages at the control connections of the power semiconductor component parts, to set an amount and/or a time curve of the electrical voltages as a function of the electric currents, to set a temporal change in the electrical voltages applied at the control connections by adjusting a slope of straight edges of the electrical voltages when the power semiconductor component parts are switched on and/or switched off as a function of the electric currents, to set the electrical voltages on the basis of voltages set during a preceding operation of the power semiconductor component, wherein the electrical currents, which flow through the power semiconductor component parts with specific settings with respect to the electrical voltages, are stored, and to determine the temporal change in the electrical voltages on the basis of the preceding settings.

9. The power semiconductor component of claim 8, wherein the at least two power semiconductor component parts are embodied as an IGBT or as a MOS FET.

10. The power semiconductor component of claim 8, wherein the driver element is configured to set the electrical voltages such that the electric currents are essentially the same.

11. The power semiconductor component of claim 8, wherein the driver element is configured to set start times and an end time, between which the electrical voltages are applied to the control connections, as a function of the electric currents.

12. The power semiconductor component of claim 8, wherein the driver element includes an output and an input for each of the power semiconductor component parts for receiving measured values which describe the electric currents.

13. The power semiconductor component of claim 8, wherein the control device comprises a further said driver element, with the driver elements operably connected to the power semiconductor component parts in one-to-one correspondence, with the driver elements having each an output for the power semiconductor component parts, respectively.

14. The power semiconductor component of claim 13, wherein the driver elements have each an input for receiving measured values which describe the electric currents through the power semiconductor component parts, said control device comprising a communication unit configured to transmit the measured values between the driver elements.

15. The power semiconductor component of claim 13, wherein the control device comprises a central computing unit configured to receive measured values which describe the electric currents, and a communication unit configured to transmit the measured values to the driver elements.

16. A method for controlling a power semiconductor component having at least two voltage-controlled power semiconductor component parts which are electrically connected in parallel and which each have a control connection, said method comprising: setting with a driver element electrical voltages at the control connections of the power semiconductor component parts; detecting by a measuring unit electric currents flowing through the respective power semiconductor component parts; setting by the driver element an amount and/or a time curve of the electrical voltages as a function of the electric currents; setting by the driver element a temporal change in the electrical voltages applied to the control connections by adjusting a slope of straight edges of the electrical voltages when the power semiconductor component parts are switched on and/or switched off as a function of the electric currents; setting by the driver element the electrical voltages on the basis of voltages set during a preceding operation of the power module; storing the electrical currents, which flow through the power semiconductor component parts with specific settings with respect to the electrical voltages; and determining the temporal change in the electrical voltages on the basis of the preceding settings.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) The invention is now explained in more detail on the basis of preferred exemplary embodiments and with reference to the appended drawings, in which:

(2) FIG. 1 shows a power semiconductor component according to an embodiment of the invention, which has two voltage-controlled power semiconductor component parts and a control device;

(3) FIG. 2 shows a time curve of the respective currents, which flow through the power semiconductor component parts;

(4) FIG. 3 shows respective electrical voltages, which are applied to control connections of the power semiconductor component parts as a function of the currents;

(5) FIG. 4 shows respective electrical voltages, which are applied to control connections of the power semiconductor component parts as a function of the currents in accordance with a further embodiment;

(6) FIG. 5 shows a power semiconductor component according to a further embodiment; and

(7) FIG. 6 shows a power semiconductor component according to a further embodiment.

(8) In the figures, similar and functionally similar elements are provided with the same reference signs.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

(9) FIG. 1 shows a power semiconductor component 1 according to an embodiment of the present invention in a schematic representation. The power semiconductor component 1 can be part of a power converter or a converter. The power semiconductor component 1 comprises a first power semiconductor component part V1 and a second power semiconductor component part V2. The power semiconductor component parts V1, V2 are embodied as MOSFETs. The power semiconductor component parts V1, V2 are electrically connected in parallel. An overall current I.sub.V is currently divided between the two power semiconductor component parts V1, V2. A current I.sub.V1 thus flows through the first power semiconductor component part V1 and a current I.sub.V2 flows through the second power semiconductor component part V2. During operation of the power semiconductor component 1, attempts are made to ensure that the electric currents I.sub.V1 and I.sub.V2 are essentially the same.

(10) Furthermore, the power semiconductor component 1 comprises a control device 2 for controlling the power semiconductor component parts V1, V2. The control device 2 comprises at least one driver element GU1, GU2, with which a respective electrical voltage U.sub.G1, U.sub.G2 can be applied to respective control connections 3 of the power semiconductor component parts V1, V2. The control connections 3 correspond to the gate connections of the MOSFETs. In the present example, a driver element GU1, GU2 is assigned to each of the power semiconductor component parts V1, V2. In this case a first driver element GU1 is assigned to the first power semiconductor component part V1, wherein an output 4 of the first driver element GU1 is connected to the control connection 3 of the first power semiconductor component part V1. The electrical voltage U.sub.G1 can thus be applied to the control connection 3 of the first power semiconductor component V1. In the same way, an electrical voltage U.sub.G2 can be applied to the control connection 3 of the second power semiconductor component V2 with the second driver element GU2.

(11) Furthermore, the control device 2 comprises a measuring unit 5, by means of which the respective currents I.sub.V1, I.sub.V2 through the power semiconductor component parts V1, V2 can be determined. The measuring unit 5 currently comprises two current sensors 6, wherein in each case a current sensor 6 is assigned to a power semiconductor component part V1, V2. The respective current sensors 6 are connected to respective inputs 7 of the driver elements GU1, GU2. Each measured value which describe the electric currents IV.sub.1, IV.sub.2 can thus be received by the driver elements GU1, GU2.

(12) Furthermore, the control device 2 comprises a communication unit 8, by means of which the driver elements GU1, GU2 are connected for data transmission purposes. This thus enables measured values to be exchanged between the driver elements GU1, and GU2. As a function of the measured values or the currents I.sub.V1 and I.sub.V2 through the power semiconductor component parts V1, V2, the electrical voltages U.sub.G1 and U.sub.G2, which are output with the driver elements GU1, UG2, can then be adjusted.

(13) FIG. 2 shows the respective electric currents I.sub.V1 and I.sub.V2 through the power semiconductor component parts V1 and V2 as a function of the time t. The diagram in FIG. 2 shows the electric current I as a function of the time t. In this regard, it should be mentioned here that the electric current I.sub.V1 through the first power semiconductor component part V1 increases as a function of the time t and the electric current I.sub.V2 through the second power semiconductor component part V2 reduces as a function of the time t. The changes to the electric currents I.sub.V1 and I.sub.V2 can be substantiated by external influences, such as heating, and by parameter fluctuations in the individual power semiconductor components V1, V2.

(14) This change in the division of the electric currents I.sub.V1, I.sub.V2 through the power semiconductor component parts V1, V2 can be detected with the aid of the driver elements GU1, GU2 on the basis of the measured value. As a function of the respective electric currents I.sub.V1, I.sub.V2, the electrical voltages U.sub.G1 and U.sub.G2, which are output by the driver elements GU1, GU2, are adjusted. This is shown in FIG. 3. At present the electrical voltage U.sub.G2 at the second power semiconductor component part V2 is increased as a function of the time t. The electrical resistance within the second power semiconductor component part V2 can thus be reduced. The electrical voltage U.sub.G1 at the first power semiconductor component V1 is reduced in the same way. The electrical resistance within the first power semiconductor component part V1 can thus be increased. Overall, it is therefore possible, for instance, for the currents, I.sub.V1, I.sub.V2, which flow through the power semiconductor component parts V1 and V2 to be essentially the same.

(15) FIG. 4 shows the curve of the electrical voltages U.sub.G1 and U.sub.G2 according to a further embodiment. Here the voltages U.sub.G1 and U.sub.G2 differ with respect to the start times t.sub.s1 and t.sub.s2, from which these are applied to the control connections 3. At present the electrical voltage U.sub.G1 is firstly applied to the control connection 3 at the start time t.sub.s1. The electrical voltage U.sub.G2 is then applied to the control connection 3 at the start time t.sub.s2. End times, from which the respective electrical voltages U.sub.G1 and U.sub.G2 are no longer applied to the control connections 3, can be adjusted similarly. Moreover, the electrical voltages U.sub.G1 and U.sub.G2 differ with respect to their temporal changes when switching-on or applying voltage. At present the electrical voltages U.sub.G1 and U.sub.G2 have straight edges with a different slope when switched on. The second power semiconductor component part V2, to which the voltage U.sub.G2 is applied, is currently switched on more quickly than the first power semiconductor component part V1, to which the voltage U.sub.G1 is applied. The second power semiconductor component part V2 thus draws dynamically more current than the first power semiconductor component part V1.

(16) FIG. 5 shows a power semiconductor component 1 according to a further embodiment. In this case, the control device 2 comprises additionally a central computing unit 9. This central computing unit 9 is connected to the respective current sensors 6 for data transmission purposes. The computing unit 9 can thus receive the measured values provided with the current sensors 6. These measured values can be transmitted to the driver elements GU1, GU2 by way of corresponding communication units 8.

(17) FIG. 6 shows the power semiconductor component 1 according to a further embodiment. In this case, the control device 2 has a single driver element GU. The driver element GU presently has a first output 4, which is connected to the first power semiconductor component part V1, and a second output 4, which is connected to the second power semiconductor component part V2. Furthermore, the driver element GU has respective inputs 7 and 7 which are connected to the respective current sensors 6.

(18) Basically there can be provision for the power semiconductor component 1 to have a plurality of power semiconductor component parts V1, V2, which are connected in parallel. With the respective driver elements GU, GU1, GU2, the amount and/or the time curve of the respective electrical voltages U.sub.G1, U.sub.G2 can be adjusted as a function of the currents I.sub.V1, I.sub.V2. Different through properties of the power semiconductor component parts V1, V2 can be compensated by adjusting the amount of voltage. Provision can also be made here for the switch-on pulses ts1, ts2 and/or the switch-off pulses to be displaced temporally in order to apply the respective electrical voltages U.sub.G1, U.sub.G2 to the power semiconductor component part V1, V2. Moreover, the time change in the electrical voltages U.sub.G1, U.sub.G2 can be adjusted as a function of the currents I.sub.V1, I.sub.V2. In this way, different stray inductances can be compensated. Furthermore, the method can be applied so that the specific switching properties, in other words the voltage curve, the amount of voltage and/or the switching times, can be obtained from current information of previous pulses. A learnable system can therefore be provided.