WO2023275981A1 - 半導体装置および電力変換装置 - Google Patents
半導体装置および電力変換装置 Download PDFInfo
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- 239000004065 semiconductor Substances 0.000 title claims abstract description 291
- 238000006243 chemical reaction Methods 0.000 title description 28
- 238000001514 detection method Methods 0.000 claims description 78
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- 238000009529 body temperature measurement Methods 0.000 description 25
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- 238000000691 measurement method Methods 0.000 description 2
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- 229910003460 diamond Inorganic materials 0.000 description 1
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
- H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
- H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
- H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M7/53—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
- H02M7/537—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters
- H02M7/539—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters with automatic control of output wave form or frequency
- H02M7/5395—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters with automatic control of output wave form or frequency by pulse-width modulation
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/0003—Details of control, feedback or regulation circuits
- H02M1/0009—Devices or circuits for detecting current in a converter
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/08—Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/32—Means for protecting converters other than automatic disconnection
- H02M1/327—Means for protecting converters other than automatic disconnection against abnormal temperatures
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
- H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
- H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
- H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
Definitions
- the present disclosure relates to semiconductor devices and power conversion devices.
- IGBTs Insulated Gate Bipolar Transistors
- MOSFETs Metal-Oxide-Semiconductor Field-Effect Transistors
- a power semiconductor device for electric power has a maximum allowable operating temperature defined by the characteristics of the semiconductor material, etc. Above that temperature, the power semiconductor device may undergo thermal runaway and be destroyed. Therefore, in recent years, temperature control of power semiconductor elements has become more important.
- Patent Document 1 Japanese Patent Application Laid-Open No. 2016-12670.
- This method is a method in which a plurality of gate electrodes are provided on a power semiconductor element and the temperature is obtained from the resistance value between the gate electrodes in an energized state.
- Patent Document 2 Yet another method is disclosed in Japanese Patent Application Laid-Open No. 2020-72569 (Patent Document 2).
- Patent Document 2 information indicating the relationship between the temperature of the power semiconductor element and the change in the gate voltage over time during the switching operation of the semiconductor device is stored in advance, and the temperature of the power semiconductor element is estimated from the gate voltage rise time. be.
- Patent Document 1 it is necessary to provide a plurality of gate electrodes in order to read the value of the gate resistance on the power semiconductor element. This becomes a constraint on miniaturization of the power module.
- the method disclosed in Patent Document 2 requires a highly accurate time measurement mechanism and a high-speed processor to measure the gate voltage rise time. can be a constraint on integration.
- the present disclosure has been made in consideration of the above problems, and one of its purposes is to provide a semiconductor device that drives and controls a power semiconductor element, while having a function of measuring the temperature of the power semiconductor element.
- An object of the present invention is to provide a semiconductor device that can be miniaturized without reducing the effective area of the semiconductor element.
- a semiconductor device that drives and controls a semiconductor element includes a pulse current source, a drive control section, a current detection section, a voltage detection section, a temperature detection section, and a timing control section.
- the semiconductor device has a positive terminal, a negative terminal, and a control terminal for supplying a drive voltage that controls current flowing between the positive and negative terminals.
- a pulsed current source is provided to apply a pulsed current between the control terminal and the negative terminal.
- the drive control unit supplies a drive voltage to the control terminal to cause the semiconductor element to transition between an ON state and an OFF state.
- the current detector detects a current flowing through the semiconductor element from a pulse current source.
- the voltage detector detects a voltage between a control terminal or a negative terminal and a reference potential.
- the temperature estimator estimates the temperature of the semiconductor element based on the values detected by the current detector and the voltage detector.
- the timing control section controls the timing of outputting the current from the pulse current source.
- the timing control unit causes the pulse current source to output a current during the ON period after the semiconductor element transitions to the ON state or during the OFF period after the semiconductor element transitions to the OFF state.
- the current is caused to flow between the control terminal and the negative terminal of the semiconductor element by the pulse current source during the ON period or the OFF period of the semiconductor element, and the voltage and current generated by this current are The temperature is estimated based on Therefore, it is possible to provide a semiconductor device having a temperature measurement function that can be miniaturized without reducing the effective area of the semiconductor element.
- FIG. 1 is a configuration diagram showing an example of a power module 101 according to Embodiment 1;
- FIG. 1B is a circuit diagram showing a configuration example of a current control unit 1 of FIG. 1A;
- FIG. 1B is a configuration diagram showing a modification of the power module 101 of FIG. 1A;
- FIG. 1B is a timing chart for explaining a temperature estimation method by the semiconductor device 100 of FIG. 1A;
- FIG. 4 is a diagram showing changes in gate capacitance of a typical MOSFET;
- FIG. 10 is a configuration diagram showing a first mode of a power module according to Embodiment 3;
- FIG. 11 is a configuration diagram showing a second aspect of the power module of Embodiment 3; 7 is a configuration diagram showing the current control unit 1, the output stage of the driver circuit 42, the resistance element 8, and the power semiconductor element 10 extracted from the circuit configuration of FIG. 6.
- FIG. 8 is a timing chart for explaining a temperature measurement method of the power semiconductor element 10 by the semiconductor device 100 shown in FIGS. 6 and 7.
- FIG. 11 is a configuration diagram showing a third aspect of the power module of Embodiment 3;
- FIG. 10 is a configuration diagram showing the current control unit 1, the output stage of the driver circuit 42, the resistance element 8, and the power semiconductor element 10 extracted from the circuit configuration of FIG. 9 (in the case of a current sink current source).
- FIG. 10 is a configuration diagram showing the current control unit 1, the output stage of the driver circuit 42, the resistance element 8, and the power semiconductor element 10 extracted from the circuit configuration of FIG. 9 (in the case of a current sink current source).
- 10 is a configuration diagram showing the current control unit 1, the output stage of the driver circuit 42, the resistance element 8, and the power semiconductor element 10 extracted from the circuit configuration of FIG. 9 (in the case of the current source of the current source).
- 10B is a timing chart for explaining a method of measuring the temperature of the power semiconductor element 10 in the case of the circuit configuration of the current control section of FIG. 10A.
- FIG. 10B is a timing chart for explaining a method of measuring the temperature of the power semiconductor element 10 in the case of the circuit configuration of the current control section of FIG. 10B.
- FIG. FIG. 11 is a configuration diagram of a power module according to Embodiment 4; 13 is a timing chart showing a method of measuring temperatures of power semiconductor elements 10A, 10B, and 10C by the semiconductor device 100 of FIG.
- FIG. 13 is a timing chart showing a method of measuring temperatures of power semiconductor elements 10A, 10B, and 10C by semiconductor device 100 of FIG. 12 (second method).
- FIG. 3 is a diagram more realistically showing an output current waveform of a current control section 1 and a detected voltage waveform of a voltage detection section 6 when a switch control signal 31 is at L level;
- FIG. 11 is a timing chart for explaining the operation of a temperature estimator in the power module of Embodiment 6; It is a figure which shows an example of the capacitance characteristic of a power semiconductor element.
- FIG. 11 is a configuration diagram of a power module according to Embodiment 7; BRIEF DESCRIPTION OF THE DRAWINGS It is a block diagram which shows the structure of the power conversion system to which the power converter device concerning this Embodiment is applied.
- FIG. 1A is a configuration diagram showing an example of a power module 101 according to Embodiment 1.
- FIG. 1B is a circuit diagram showing a configuration example of the current control section 1 of FIG. 1A. The configuration of the power module 101 will be described below with reference to FIGS. 1A and 1B.
- the power module 101 includes a power semiconductor element 10 and a semiconductor device 100 that drives and controls the power semiconductor element 10 .
- the semiconductor device 100 controls switching of the power semiconductor element 10 and measures the element temperature of the power semiconductor element 10 .
- the semiconductor device 100 includes a gate driver 4, a current controller 1, a timing controller 3, a current detector 5, a voltage detector 6, a temperature estimator 7, and a resistance element 8 (also called gate resistance). and
- the gate drive section 4 includes a driver circuit 42 as a drive control section that is connected to the power semiconductor element 10 to drive the power semiconductor element 10 and a main control section 41 that controls the driver circuit 42 .
- the current control section 1 is connected to the driver circuit 42 and supplies current between the control terminal G and the negative terminal S of the power semiconductor element 10 via the driver circuit 42 .
- the current controller 1 includes a pulse current source 20 capable of supplying pulsed current.
- pulse current source 20 includes, for example, current source 11 and current control switch 12 connected in parallel with current source 11 . By switching the current control switch 12 from the closed state to the open state, the pulse current source 20 starts outputting current, and by switching the current control switch 12 from the open state to the closed state, the pulse current source 20 starts to output current. end the output of
- the current source 11 for example, a bipolar transistor, a current mirror, or a constant voltage source provided with a resistor on the output side may be used. can be used. Also, the current source 11 may be configured as a current source that outputs current or as a current sink that sinks current, depending on its circuit configuration.
- the current control switch 12 can use a switching element such as a MOSFET that operates at a relatively high speed. If measurement accuracy is required, an ultra-high-speed device such as a GaN HEMT (High Electron Mobility Transistor) may be used as the current control switch 12 .
- each of the current source 11 and the current control switch 12 is connected to a reference potential node 90 that provides a reference potential.
- the reference potential is, for example, the control ground of the driver circuit 42 or the power supply voltage of the driver circuit 42 .
- the other ends of the current source 11 and the current control switch 12 are directly or indirectly connected to the control terminal G or negative terminal S of the power semiconductor element 10 .
- the other ends of the current source 11 and the current control switch 12 are connected to the power semiconductor device 10 via other electronic components such as semiconductor switching devices or resistors mounted in the driver circuit 42. It is connected to the control terminal G or the negative terminal S.
- the control terminal G is also referred to as the gate G
- the negative terminal S is also referred to as the source S.
- the voltage detection unit 6 is connected to the driver circuit 42 and directly or indirectly detects the voltage between the control terminal G or the negative terminal S and the reference potential via the driver circuit 42 .
- semiconductor switching elements or resistors which are other electronic components mounted in the driver circuit 42, are included between the voltage detection section and the power semiconductor element.
- the detected value of the voltage detection unit 6 includes the influence of potential effects due to other electronic components.
- the timing control section 3 outputs a switch control signal 31 for controlling the current control switch 12 of the current control section 1 based on the command 412 from the main control section 41 of the gate driving section 4 .
- the timing control section 3 and the gate driving section 4 are clearly distinguished for the sake of explanation, but the timing control section 3 may be included in the main control section 41 .
- the driver circuit 42 and the timing control section 3 may be mounted on the same board, or the main control section 41, the driver circuit 42, the timing control section 3, and the current control section 1 may all be mounted on the same board. I don't mind.
- the main control section 41 controls the driver circuit 42 and the timing control section 3 as already described.
- functional devices such as a microprocessor, ASIC (Application Specific Integrated Circuit), and FPGA (Field Programmable Gate Array) are used.
- the power semiconductor element 10 may be a MOSFET, an IGBT, a MESFET (Metal-Semiconductor Field-Effect Transistor), a bipolar transistor, or the like.
- a MOSFET will be described below as an example.
- Si, SiC, GaN, Ga 2 O 3 , diamond, or the like may be used as the material of the power semiconductor element 10 .
- the power semiconductor element 10 includes a positive terminal D, a negative terminal S, and a control terminal G. As shown in FIG. The current flowing between the positive terminal D and the negative terminal S is controlled by the driving voltage applied to the control terminal G.
- the control terminal G of the power semiconductor element 10 is connected to the driver circuit 42 through the resistance element 8 provided in the gate wiring section 2, for example.
- the gate wiring portion 2 represents a series of loop wirings connecting the control terminal G, the negative terminal S, and the driver circuit 42 of the power semiconductor element 10 .
- the current detection section 5 detects the current flowing through the gate wiring section 2 . Therefore, the current detection unit 5 detects the current flowing through the power semiconductor element 10 from the current source 11 when the current control switch 12 is in the open state.
- the current detector 5 estimates the current from the voltage across the resistance element 8 connected to the control terminal G of the power semiconductor element 10, as an example. In this case, for example, an instrumentation amplifier can be used as the current detector 5 .
- the resistor element 8 is clearly shown, but depending on the application, there may be cases where the gate resistor is not provided outside the power semiconductor element 10.
- FIG. Other configurations of the current detection unit 5 include a current transformer, a Hall element, a Rogowski coil, and the like.
- the temperature estimation unit 7 calculates the resistance value of the power semiconductor element 10 based on the detection value of the voltage detection unit 6, the detection value of the current detection unit 5, and the control information 32 of the timing control unit 3.
- the temperature estimator 7 converts the newly measured resistance value of the power semiconductor element 10 into a temperature by comparing with conversion data indicating the relationship between the resistance value and the element temperature measured and recorded in advance. The converted temperature information is fed back to the main controller 41 .
- the main control unit 41 changes the drive pattern so as to reduce the loss of the power semiconductor element, and outputs warning information to a higher system. can do.
- FIG. 1A shows the main controller 41 and the temperature estimator 7 as separate configurations for the sake of explanation, the function of the temperature estimator 7 may be included in the main controller 41 .
- FIG. 2 is a configuration diagram showing a modification of the power module 101 of FIG. 1A.
- the resistive element 8 is connected not to the wiring (gate wiring) connected to the control terminal G but to the wiring (source wiring) connected to the negative terminal S, which is different from that shown in FIG. 1A. is different from the power module 101 of In this case as well, the resistance element 8 is still provided for detecting the current flowing through the gate wiring portion 2 .
- Other points in FIG. 2 are the same as in FIG. 1A, so the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.
- FIG. 3 is a timing chart for explaining the temperature estimation method by the semiconductor device 100 of FIG. 1A.
- waveforms up to time t2 show voltage waveforms and signal waveforms during normal switching operation without temperature measurement
- waveforms after time t2 show voltage waveforms and signal waveforms when temperature measurement is performed along with switching operation. show.
- the driver circuit 42 outputs a positive potential Vcc higher than the threshold voltage and a potential Vee lower than the threshold voltage (usually a negative potential or zero potential) to drive the power semiconductor element 10 .
- driver circuit 42 applies positive potential Vcc or negative or zero potential Vee as a gate voltage to control terminal G of power semiconductor element 10 based on input signal 411 from main control section 41 .
- the timing control section 3 always controls the current control switch 12 of the current control section 1 to be in a conductive state. Therefore, when the current control switch 12 uses an enhancement element such as an n-type MOSFET, a high (H) level signal is always input as the switch control signal 31 for the current control switch 12 . When a depletion type element such as a p-type MOSFET is used for the current control switch 12 , a low (L) level signal is always input as the switch control signal 31 .
- the input signal 411 of the driver circuit 42 changes from H level to L level at time t1.
- a negative or zero potential Vee is applied to the control terminal G of the power semiconductor element 10, and the gate voltage drops.
- the gate voltage reaches the negative or zero potential Vee at time t1' through a falling period as in the case of turn-on.
- gate current flows through current control switch 12 to reference potential node 90 .
- Current from current source 11 flows through current control switch 12 to reference potential node 90 and is not output to driver circuit 42 . Note that the mirror voltage is also observed during the fall period.
- the temperature measurement is performed during a period in which the gate voltage is stable other than the rise period and fall period of the gate voltage.
- the period during which the gate voltage is stable includes the period during which the gate voltage is stable at the positive potential Vcc (hereinafter referred to as "on period") and the period during which the gate voltage is stable at the negative or zero potential Vee ( hereinafter referred to as "off period").
- switch control signal 31 switches to L level at time t3 after a predetermined delay period has elapsed.
- This delay time can be simply set as a time constant consisting of the resistance value of the resistance element 8 and the element capacitance of the power semiconductor element 10, or a time longer than that. If this delay time is short, the gate driving current from the driver circuit 42 is also detected by the current detecting section 5, which affects the accuracy of temperature measurement. On the other hand, if this delay time is long, the time t4 at which the switch control signal 31 is returned to the H level becomes closer to the turn-off start time t5. As a result, the gate drive current from the driver circuit 42 is also detected by the current detector 5, which affects the accuracy of temperature measurement.
- the switch control signal 31 becomes L level (time t3)
- the current control switch 12 in FIG. 1B is turned off.
- the current from current source 11 flows not to reference potential node 90 but to power semiconductor element 10 .
- the voltage detected by the voltage detection unit 6 is represented by the following equation (1).
- V Ig (t ⁇ t3) represents the voltage detected by voltage detection unit 6 at time t.
- R gint is the value of the gate resistance (built-in gate resistance) present in the power semiconductor device 10 .
- the built-in gate resistor is made of a material such as polysilicon on the power semiconductor element 10, for example.
- the built-in gate resistance includes parasitic resistance due to the gate wiring pattern on the power semiconductor element 10 .
- Rg represents the resistance on the driver circuit 42 and the value of the resistive element 8, and represents a resistance component other than the resistance caused by the power semiconductor element 10 itself.
- C die represents a capacitance value viewed from the gate side of the power semiconductor device 10 .
- Ig represents the supply current from the current source 11;
- the charging voltage of the parasitic capacitance of the power semiconductor element 10 is (t ⁇ t3) ⁇ I g / It rises according to C die .
- the voltage detected by the voltage detection unit 6 linearly rises. Therefore, the voltage detection value at arbitrary time t3', the elapsed time ( t3' -t3) from time t3 when the current control switch 12 is turned off, and the gate current value Ig detected by the current detection unit 5 are used. , the resistance value R g +R gint can be calculated.
- each of the resistance values R g and R gint has temperature dependence.
- R gint (T) ⁇ R gint0 (1+K 2 ⁇ T) is represented as If the temperature dependence of the resistance Rg other than the built-in gate resistance of the power semiconductor element 10 is sufficiently smaller than the temperature dependence of the built-in gate resistance Rgint of the power semiconductor element 10, that is, if ⁇ R g ⁇ R gint , the resistance value
- the temperature dependence of R g +R gint represents the temperature dependence of the built-in gate resistance of the power semiconductor device 10 .
- the temperature of the power semiconductor element 10 can be calculated by comparing the resistance value R g +R gint obtained by the above calculation with the previously recorded calibration data representing the relationship between the resistance value and the temperature.
- the resistance value R g It can be obtained by calculating +R gint . If it is difficult to obtain the calibration data, the rate of change (temperature coefficient) of the built-in gate resistance R gint due to temperature is obtained in advance, and calculation using the obtained temperature coefficient can be performed instead.
- this delay time can be simply set as a time constant consisting of the resistance value of the resistance element 8 and the element capacitance of the power semiconductor element 10, or a time longer than that. If this delay time is short, the gate driving current from the driver circuit 42 is also detected by the current detecting section 5, which affects the accuracy of temperature measurement.
- the voltage detected by the voltage detecting section 6 rises linearly, as in the measurement during the ON period. Therefore, the voltage detection value at an arbitrary time t6' between time t6 and time t7, the elapsed time (t6'-t6) from time t6 when the current control switch 12 was turned off, and the current detection unit 5 detect Using the calculated gate current value I g , the resistance value R g +R gint can be calculated.
- the temperature dependence of the gate resistances other than the built-in gate resistance of the power semiconductor element 10 is sufficiently smaller than the temperature dependence of the built-in gate resistance, the temperature dependence of the resistance value R g +R gint is Represents the temperature dependence of the built-in gate resistance. Therefore, the temperature of the power semiconductor element 10 can be calculated by comparing the resistance value R g +R gint obtained by the above calculation with the previously recorded calibration data representing the relationship between the resistance value and the temperature.
- the timing of starting the injection of the gate current is defined as the delay time set as a time constant consisting of the gate resistance and the element capacitance, or a time longer than that, based on the rise and fall timings of the driver voltage. be able to.
- Embodiment 2 In practice, the gate capacitance C die of the power semiconductor device 10 changes according to the terminal voltage of the power semiconductor device 10 . Therefore, in the second embodiment, a method for suppressing the influence of changes in the gate capacitance C die will be described.
- FIG. 4 is a diagram showing changes in gate capacitance of a typical MOSFET.
- the gate capacitance C die has a substantially constant value in a region where the gate-source voltage Vgs is sufficiently low (accumulation region) and a region where the gate-source voltage Vgs is sufficiently high (inversion region).
- the gate capacitance C die varies greatly.
- the variation of the gate capacitance C die in the intermediate region is about 30% of the gate capacitance C die in the accumulation region.
- Such characteristics can be confirmed in advance, for example, by measuring the gate-source voltage Vgs dependency of the gate capacitance C die for MOSFETs before shipment.
- the voltage of the voltage detection unit 6 does not rise linearly as shown in equation (1), affecting the accuracy of temperature estimation.
- the source-to-source voltage Vgs changes.
- the timing control unit 3 reduces the amount of change in the voltage value detected by the voltage detection unit 6 to a certain voltage V1 or less.
- the switch control signal 31 is held at the L level only for a certain period of time t4-t3, and when the amount of change in the detected voltage exceeds the voltage V1, the switch control signal 31 is brought to the H level.
- current control switch 12 is turned on, and voltage Vgs applied between the gate and source of power semiconductor device 10 becomes equal to the voltage supplied from driver circuit .
- the device capacitance C die also changes depending on the drain-source voltage of the power semiconductor device 10 . Therefore, the degree of change in the element capacitance C die differs between the ON period and the OFF period. For this reason, in the measurement during the OFF period, the timing control unit 3 controls the voltage detection unit 3 to set the amount of change in the voltage detected by the voltage detection unit to be equal to or less than a certain voltage V2 different from the above voltage V1, and the constant period t5-t6. Only during this period, the switch control signal 31 is held at L level to turn off the current control switch 12 . By returning the switch control signal 31 to the H level at time t6, the current control switch 12 becomes conductive, and the gate-source voltage Vgs of the power semiconductor device 10 becomes equal to the voltage supplied from the driver circuit 42.
- the main control unit 41 performs timing control so that the amount of change in the voltage detected by the voltage detection unit 6 is equal to or less than the threshold, thereby estimating the temperature. It is possible to prevent deterioration of accuracy.
- Embodiment 3 The configuration of the semiconductor device 100 of the power module 101 according to the third embodiment will be described below with reference to FIGS. 5 to 11B.
- the configuration of the current control section 1 is shown more specifically, unlike the case of FIGS. 1A and 1B. Except for the current control unit 1, the configuration of the power module 101 of the third embodiment is the same as that of the first and second embodiments. do not repeat the description.
- the current source 11 constituting the current control unit 1 a current source that supplies current to the load or a current sink that absorbs current from the load can be used.
- FIG. 5 is a configuration diagram showing a first mode of the power module of Embodiment 3.
- FIG. FIG. 5 shows an example in which the current control section 1 is arranged on the source S side of the power semiconductor element 10 .
- the reference potential of the current controller 1 is the control ground 900 of the driver circuit 42 .
- the current source 11 and the current control switch 12 are thus connected between the negative terminal S of the power semiconductor component 10 and the control ground 900 .
- All the current from the current source 11 flows to the reference potential 900 when the switch control signal 31 is at H level, that is, when the current control switch 12 is in a conductive state.
- the switch control signal 31 is at L level
- the current from the current source 11 flows toward the power semiconductor element 10 and flows from the source S into the power semiconductor element 10 . Therefore, the gate-source voltage Vgs of the power semiconductor device 10 changes as shown from time t3 to time t4 in FIG. 3 during the ON period, and changes from time t6 to time t6 in FIG. It changes as shown at t7.
- the voltage between the gate and the source and the voltage between the drain and the source applied to the power semiconductor element 10 are different during the ON period and during the OFF period, respectively, and as a result, the capacitance C die of the power semiconductor element 10 is also different. Therefore, the voltage waveform of the gate voltage is not the same during the ON period and during the OFF period. Therefore, the voltage detected by the voltage detection unit 6 is V1 during the ON period and V1 during the OFF period, as shown in FIG. takes different values such as V2.
- FIG. 6 is a configuration diagram showing a second aspect of the power module according to the third embodiment.
- FIG. 6 shows an example in which the current control section 1 is arranged on the gate side of the power semiconductor element 10 .
- a current source is used for the current source 11 .
- the reference potential of the current controller 1 is the control ground 900 of the driver circuit 42 .
- FIG. 7 is a configuration diagram showing the current control unit 1, the output stage of the driver circuit 42, the resistance element 8, and the power semiconductor element 10 extracted from the circuit configuration of FIG.
- the output stage of driver circuit 42 includes a high potential side switch 42H and a low potential side switch 42L connected in series.
- One end of the high potential side switch 42H is connected to the positive potential Vcc.
- One end of the low potential side switch 42L is connected to the reference potential 900 via the current source 11 and the current control switch 12 of the current control section 1.
- Each other end of the high potential side switch 42H and the low potential side switch 42L (that is, the connection point of these switches 42H and 42L) is connected to the control terminal G of the power semiconductor device 10 via the resistive element 8 .
- Current source 11 and current-controlled switch 12 are therefore connected between control terminal G of power semiconductor component 10 and control ground 900, which provides a reference potential.
- the current from the current source 11 of the current control unit 1 is supplied to the power semiconductor element 10 only when the output of the driver circuit 42 is at L level (that is, only when the low potential side switch 42L is in the ON state). can be supplied to the control terminal G of
- FIG. 8 is a timing chart for explaining the method of measuring the temperature of the power semiconductor element 10 by the semiconductor device 100 shown in FIGS. 6 and 7.
- the main control unit 41 sets the switch control signal 31 to L level between time t6 and time t7 after time t5 when the driver input signal 411 is at L level.
- a current from the current source 11 is input to the control terminal G of the power semiconductor element 10 .
- FIG. 9 is a configuration diagram showing a third mode of the power module according to the third embodiment.
- FIG. 9 shows an example in which the current control section 1 is arranged on the gate side of the power semiconductor element 10 .
- the current source 11 can be a current source or a current sink.
- Reference potential 901 of driver circuit 42 will be described later with reference to FIGS. 10A and 10B.
- FIG. 10A and 10B are configuration diagrams showing the current control unit 1, the output stage of the driver circuit 42, the resistance element 8, and the power semiconductor element 10 extracted from the circuit configuration of FIG.
- the circuit diagram of FIG. 10A shows a case where a current sink is used as the current source 11, and the circuit diagram of FIG. 10B shows a case where the current source 11 is a current source.
- the output stage of the driver circuit 42 includes a high potential side switch 42H and a low potential side switch 42L connected in series with each other.
- One end of the high potential side switch 42H is connected to the reference potential 901 via the current source 11 and the current control switch 12 of the current control section 1 .
- the reference potential 901 in this case is equal to the power supply voltage Vcc of the driver circuit 42 .
- One end of the low potential side switch 42L is connected to the ground potential Vee of the driver circuit 42 .
- Each other end of the high potential side switch 42H and the low potential side switch 42L (that is, the connection point of these switches 42H and 42L) is connected to the control terminal G of the power semiconductor device 10 via the resistive element 8 . Therefore, current source 11 and current control switch 12 are connected between control terminal G of power semiconductor element 10 and reference potential 901 equal to power supply voltage Vcc of driver circuit 42 .
- the output stage of driver circuit 42 includes a high potential side switch 42H and a low potential side switch 42L connected in series with each other.
- One end of the high-potential side switch 42H is connected to the power supply voltage Vcc of the driver circuit 42 via the disconnecting switch 43, and is connected to the reference potential 901 via the current source 11 and the current control switch 12 of the current control section 1. be done.
- the reference potential 901 in this case is higher than the power supply voltage Vcc of the driver circuit 42 .
- Each other end of the high potential side switch 42H and the low potential side switch 42L (that is, the connection point of these switches 42H and 42L) is connected to the control terminal G of the power semiconductor device 10 via the resistive element 8 . Therefore, current source 11 and current control switch 12 are connected between control terminal G of power semiconductor element 10 and reference potential 901 higher than power supply voltage Vcc of driver circuit 42 .
- the disconnecting switch 43 is provided to disconnect the driver circuit 42 from the power supply voltage Vcc of the driver circuit 42 while current is being supplied from the current source 11 of the current control section 1 . Thereby, the current output from the current source 11 of the current control section 1 can be supplied to the power semiconductor element 10 .
- the disconnecting switch 43 is controlled at the same timing as the switch control signal 31 .
- a signal obtained by shifting the reference potential of the switch control signal 31 by a level shifter or the like can be used as the control signal for the disconnecting switch 43 .
- FIG. 11A is a timing chart for explaining the temperature measurement method of the power semiconductor element 10 in the case of the circuit configuration of the current control section of FIG. 10A.
- the current source 11 of the current control section 1 is connected to the high potential side of the output stage of the driver circuit 42 as a current sink.
- the main control unit 41 sets the switch control signal 31 to the L level only from time t3 to time t4 during the ON period of FIG. can be absorbed.
- the gate voltage decreases and the voltage detected by the voltage detector 6 increases.
- FIG. 11B is a timing chart for explaining the method of measuring the temperature of the power semiconductor element 10 in the case of the circuit configuration of the current control section of FIG. 10B.
- the current source 11 of the current control section 1 is connected as a current source to the high potential side of the output stage of the driver circuit 42 .
- the main control unit 41 sets the switch control signal 31 to L level only from the time t3 to the time t4 during the ON period of FIG. can be supplied to G.
- the gate voltage rises and the voltage detected by the voltage detector 6 rises.
- the driver circuit 42 supplies current to the control terminal G of the power semiconductor element 10 only when the power semiconductor element 10 is on. can. 5, 6 and 9 of the third embodiment, even when the current output from the current control unit 1 is supplied to the control terminal G of the power semiconductor element 10, the negative terminal S , the temperature of the power semiconductor element 10 can be estimated.
- Embodiment 4 describes an example in which a plurality of power semiconductor elements 10 are connected in parallel. A case where three power semiconductor elements 10A, 10B, and 10C are connected in parallel will be described below, but the number of power semiconductor elements 10 connected in parallel is not limited to three. When collectively referring to the plurality of power semiconductor elements 10A, 10B, and 10C, or when indicating an arbitrary one, the power semiconductor element 10 is used.
- FIG. 12 is a configuration diagram of the power module of the fourth embodiment.
- the semiconductor device 100 of FIG. 12 further includes a switching circuit (MUX) 51 and resistance elements 8A, 8B, and 8C connected to control terminals G of the power semiconductor elements 10A, 10B, and 10C, respectively.
- MUX switching circuit
- resistance elements 8A, 8B, and 8C connected to control terminals G of the power semiconductor elements 10A, 10B, and 10C, respectively. is different from the semiconductor device 100 of Other points in FIG. 12 are the same as in FIG. 1A, so the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.
- the switching circuit 51 is connected between the current detection section 5 and each control terminal G of the power semiconductor elements 10A, 10B, 10C.
- the current detection unit 5 detects currents flowing through the gate wirings including the resistance elements 8A, 8B, and 8C.
- the gate current Ig of each power semiconductor element 10 is detected from the voltage across each of the resistance elements 8A, 8B, 8C.
- a signal for controlling switching by the switching circuit 51 may be supplied via the temperature estimation unit 7 or may be supplied directly from the main control unit 41 .
- the current detection section is provided so as to detect the current flowing through the gate wiring section including the resistance elements 8A, 8B, and 8C, for example.
- the gate resistance may not be provided outside the power semiconductor element 10, and the resistance element may be provided on the source side.
- Other configuration examples of the current detector 5 include a current transformer, a Hall element, and a Rogowski coil.
- 13 and 14 are timing charts showing the temperature measurement method of the power semiconductor elements 10A, 10B, and 10C by the semiconductor device 100 of FIG. The following two methods are conceivable for the switching timing of the switching circuit 51 of FIG.
- the first method is to switch the gate wiring portion 2 to be measured during one switching cycle, as shown in FIG. Although FIG. 13 shows the measurement method during the ON period, the temperature of each power semiconductor element 10 can be similarly measured during the OFF period.
- the switch of the switching circuit 51 is switched in order of the terminals posA, posB, and posC.
- terminal posA is connected to resistive element 8A
- terminal posB is connected to resistive element 8B
- terminal posC is connected to resistive element 8C. That is, each terminal is connected to power semiconductor elements 10A, 10B, and 10C.
- the main control unit 41 connects the switch of the switching circuit to the terminal posA at the start of the sequence. Therefore, the temperature of the power semiconductor element 10A is measured first.
- the timing control section 3 changes the switch control signal 31 to L level.
- the current detector 5 measures the current IA in the path passing through the power semiconductor element 10A.
- Voltage detector 6 measures the voltage of the parallel connection circuit of power semiconductor elements 10A, 10B, and 10C. That is, according to the equation (1), the voltage detected by the voltage detection unit 6 rises to the voltage V0 corresponding to the resistance component of the power semiconductor element, then the element capacitance C die , the gate current value I g , and the conduction period t4A ⁇ It rises to voltage V1 according to t3A.
- the temperature estimator 7 calculates the equivalent resistance value of the power semiconductor element 10A from the voltage value and the current value during this period, and estimates the temperature of the power semiconductor element 10A from a comparison with previously acquired calibration data. do.
- the timing control unit 3 changes the switch control signal 31 to H level.
- the gate voltage of the power semiconductor element 10A returns to the power supply voltage Vcc of the driver circuit 42.
- FIG. The certain period of time is selected, for example, as described in the second embodiment, so that the voltage rise amount is determined so as to reduce the fluctuation of the capacitance C die of the power semiconductor element.
- This delay time is, for example, a value longer than the time constant that can be calculated from the change in gate voltage (V1), the capacitance C die of the power semiconductor element, the gate resistance R g , and the built-in gate resistance R gint .
- the timing control section 3 supplies current from the current source 11 of the current control section 1 to each power semiconductor element 10 by setting the switch control signal 31 to the L level again. Since the switch of the switching circuit 51 is connected to the terminal posB, the current detection section 5 detects the current IB on the path passing through the power semiconductor element 10B. Voltage detector 6 detects the voltage of the parallel connection circuit of power semiconductor elements 10A, 10B, and 10C. That is, according to the equation (1), the voltage detected by the voltage detection unit 6 rises to the voltage V0 corresponding to the resistance component of the power semiconductor element, then the element capacitance C die , the gate current value I g , and the conduction period t4B ⁇ It rises to voltage V1 according to t3B.
- the time from time t3B to time t4B is the same as the time from time t3A to time t4A, so the voltage detected by the voltage detection unit 6 rises to the same V1.
- the temperature estimating unit 7 calculates an equivalent resistance value of the power semiconductor element 10B from the voltage value and the current value during this period, and estimates the temperature of the power semiconductor element 10B from a comparison with previously acquired calibration data. do.
- the timing control section 3 sets the switch control signal 31 to H level. As a result, when the current injection to the power semiconductor element 10B stops, the gate voltage of the power semiconductor element 10B returns to the power supply voltage Vcc of the driver circuit 42.
- This delay time is, for example, a value longer than the time constant that can be calculated from the change in gate voltage (V1), the capacitance C die of the power semiconductor element, the gate resistance R g , and the built-in gate resistance R gint .
- the timing control section 3 supplies current from the current source 11 of the current control section 1 to each power semiconductor element 10 by setting the switch control signal 31 to L level again. Since the switch of the switching circuit 51 is connected to the terminal posC, the current detection section 5 detects the current IC on the path passing through the power semiconductor element 10C. Voltage detector 6 detects the voltage of the parallel connection circuit of power semiconductor elements 10A, 10B, and 10C. That is, according to the equation (1), the voltage detected by the voltage detection unit 6 rises to the voltage V0 corresponding to the resistance component of the power semiconductor element, then the element capacitance C die , the gate current value I g , and the conduction period t4C ⁇ It rises to voltage V1 according to t3C.
- the time from time t3C to time t4C is the same as the time from time t3A to time t4A, so the voltage detected by the voltage detector 6 rises to the same V1.
- the temperature estimator 7 calculates the equivalent resistance of the power semiconductor element 10C from the voltage value and the current value during this period, and estimates the temperature of the power semiconductor element 10C from a comparison with previously acquired calibration data. .
- the power semiconductor elements 10A, 10B and 10C have different built-in gate resistances, external resistance elements 8A, 8B and 8C, element capacitances Cdie, and element temperatures, the currents IA and IB detected by the current detector 5 are different. , IC are also different.
- the device temperatures of the power semiconductor devices 10 connected in parallel can be individually measured without increasing the driver circuit 42 and the current detection unit 5. .
- the second method is to switch the gate wiring section 2 to be measured for each switching cycle.
- FIG. 14 shows the measurement method during the ON period, but the temperature of each power semiconductor element 10 can be similarly measured during the OFF period, except that the gate voltage and the driver input signal 411 are different.
- the terminal posA is selected as the initial setting of the connection destination of the changeover switch of the switching circuit 51 below, the terminals posB and posC may be the initial setting of the connection destination.
- the timing control section 3 sets the switch control signal 31 to the L level at time t3A after a certain period of time has passed, the current starts to flow from the current control section to the power semiconductor elements 10A, 10B, and 10C.
- the current detecting section 5 detects the current IA flowing through the power semiconductor element 10A.
- voltage detector 6 detects the voltage of the parallel connection circuit of power semiconductor elements 10A, 10B, and 10C.
- the voltage detected by the voltage detection unit 6 rises to the voltage V0 corresponding to the resistance component of the power semiconductor element, then the element capacitance C die , the gate current value I g , and the conduction period t4A ⁇ It rises to voltage V1 according to t3A.
- the temperature estimator 7 calculates the equivalent resistance value of the power semiconductor element 10A from the voltage value and the current value during this period, and estimates the temperature of the power semiconductor element 10A from a comparison with previously acquired calibration data. do.
- timing control unit 3 changes the switch control signal 31 to H level, current injection to the power semiconductor element 10A stops, and the gate voltage of the power semiconductor element 10A returns to the power supply voltage Vcc of the driver circuit 42.
- the main control section 41 connects the switch of the switching circuit 51 to the terminal posB.
- the switching timing of the switching circuit 51 is set to be the same as the timing of changing the driver input signal 411 to H level, but the timing may not necessarily be the same.
- the switching timing of the switching circuit 51 may be before the timing when the switch control signal 31 is changed to L level again.
- the timing control section 3 changes the switch control signal 31 to the L level again while the switch of the switching circuit 51 is connected to the terminal posB. Thereby, the current from the current control unit 1 flows through the power semiconductor elements 10A, 10B, and 10C.
- the current detection unit 5 detects the current IB in the path passing through the power semiconductor element 10B.
- Voltage detector 6 detects the voltage of the parallel connection circuit of power semiconductor elements 10A, 10B, and 10C.
- the voltage detected by the voltage detection unit 6 rises to the voltage V0 corresponding to the resistance component of the power semiconductor element, then the element capacitance C die , the gate current value I g , and the conduction period t4B ⁇ It rises to voltage V1 according to t3B.
- the temperature estimating unit 7 calculates an equivalent resistance value of the power semiconductor element 10B from the voltage value and the current value during this period, and estimates the temperature of the power semiconductor element 10B from a comparison with previously acquired calibration data. do.
- the timing control section 3 sets the switch control signal 31 to H level, so the current control section 1 no longer outputs current, so the gate voltage of the power semiconductor element returns to the power supply voltage Vcc of the driver circuit 42.
- the main control section 41 turns off each power semiconductor element 10 by setting the driver input signal 411 to L level.
- the main control unit 41 connects the switch of the switching circuit 51 to the terminal posC.
- the switching timing of the switching circuit 51 is set to be the same as the timing of changing the driver input signal 411 to H level, but the timing may not necessarily be the same.
- the switching timing of the switching circuit 51 may be before the timing when the switch control signal 31 is changed to L level again.
- the timing control section 3 changes the switch control signal 31 to the L level again while the switch of the switching circuit 51 is connected to the terminal posC. Thereby, the current from the current control unit 1 flows through the power semiconductor elements 10A, 10B, and 10C.
- the current detector 5 detects the current IB in the path passing through the power semiconductor element 10C.
- Voltage detector 6 detects the voltage of the parallel connection circuit of power semiconductor elements 10A, 10B, and 10C.
- the voltage detected by the voltage detection unit 6 rises to the voltage V0 corresponding to the resistance component of the power semiconductor element, then the element capacitance C die , the gate current value I g , and the conduction period t4C ⁇ It rises to voltage V1 according to t3C.
- the temperature estimating unit 7 calculates the equivalent resistance value of the power semiconductor element 10C from the voltage value and current value during this period, and estimates the temperature of the power semiconductor element 10C from a comparison with previously acquired calibration data. do.
- the timing control section 3 sets the switch control signal 31 to H level
- the current control section 1 stops outputting current, so the gate voltage of the power semiconductor element returns to the power supply voltage Vcc of the driver circuit 42.
- the main control unit 41 turns off each power semiconductor element 10 by setting the driver input signal 411 to L level.
- the current detector 5 is connected to the plurality of power semiconductor elements 10 via the switching circuit 51, respectively, so that the plurality of power semiconductor elements 10 connected in parallel are connected. temperature can be detected individually.
- Embodiment 5 the details of the temperature estimation method by the temperature estimation unit 7 will be described. Points other than the temperature estimating unit 7 are the same as those described in the first to fourth embodiments, so the description will not be repeated. In addition, although the temperature measurement during the ON period of the power semiconductor element 10 will be described below, the same applies to the temperature measurement during the OFF period.
- FIG. 15 is a diagram more realistically showing the waveform of the output current of the current control section 1 and the waveform of the detected voltage of the voltage detection section 6 when the switch control signal 31 is at L level.
- switch control signal 31 becomes L level at time t3
- current flowing from current source 11 to current control switch 12 in current control unit 1 changes to flow to power semiconductor element 10.
- a surge current and a surge voltage are generated due to changes in wiring inductance and current from the current source 11 .
- the waveform of the output current of the current control section 1 and the waveform of the detected voltage of the current detection section 5 oscillate.
- the waveform of the voltage detected by the current detection unit 5 does not necessarily rise linearly due to the influence of external noise other than the above and noise generated from the current source 11 .
- the current detection unit 5 measures the voltage at time t31 after the surge current and surge voltage have decreased from the time t3.
- the equivalent resistance value of power semiconductor element 10 can be calculated from the voltage and current values detected at time t31. If the time difference ⁇ t between time t31 and time t3 is within an allowable range, the above resistance value is considered to represent the resistance of power semiconductor element 10 .
- I g ⁇ (t31 ⁇ t3)/C die which is a voltage value calculated from the output current from current control unit 1 and capacitance C die of power semiconductor element 10 can be selected so as to be equal to or lower than the detection sensitivity of the voltage detection unit 6 .
- the temperature of the power semiconductor element 10 can be estimated from the detection data at one point of time t31.
- the voltage is detected by the voltage detection unit 6 at time t32 immediately before the switch control signal 31 is returned to H level.
- the above describes an example in which the temperature measurement time is up to two points in time, but by further increasing the number of data points, the calculation accuracy of the slope can be improved.
- the method of least squares or the like is used to calculate the slope from a plurality of data points. By doing so, the noise from the current control section 1 and the measurement error of the voltage detection section 6 are averaged.
- temperature measurement accuracy can be improved by using time information for calculation.
- Embodiment 6 describes the temperature estimation operation by the temperature estimator 7 using a method different from that of Embodiment 5.
- FIG. Points other than the temperature estimating unit 7 are the same as those described in the first to fourth embodiments, so the description will not be repeated.
- the temperature measurement during the ON period of the power semiconductor element 10 will be described below, the same applies to the temperature measurement during the OFF period.
- FIG. 16 is a timing chart for explaining the operation of the temperature estimator in the power module of the sixth embodiment.
- FIG. 17 is a diagram showing an example of capacitance characteristics of a power semiconductor device.
- the capacitance C die of the power semiconductor element changes according to the gate-source voltage V gs and the drain-source voltage V ds of the power semiconductor element.
- FIG. 16 shows an example in which the capacitance characteristics vary greatly depending on the gate-source voltage Vgs within the range of the maximum voltage variation V1 during temperature measurement because the power supply voltage Vcc of the driver circuit 42 is low.
- C die (V gs ) represents a function of the gate-source voltage Vgs of the element capacitance C die .
- the capacitance characteristic indicating the relationship between the element capacitance C die of the power semiconductor element 10 and the gate-source voltage V gs is acquired in advance, and the data is stored in the memory of the main control unit 41.
- the voltage detection unit 6 continuously acquires voltage data from time t31 to time t32.
- the gate-source voltage of the power semiconductor element 10 can be calculated by using the detection data of the voltage detection unit 6 and the value of the power supply voltage Vcc or the ground voltage Vee. From previously acquired capacitance characteristic data, gate-source voltage data, and measurement time information, an approximate straight line Vfit of the voltage detected by the voltage detection unit 6 when the element capacitance C die is constant can be calculated. This approximate straight line Vfit of the detected voltage is linear because the element capacitance C die is constant. Therefore, voltage V0 at time t3 can be calculated from the time information at times t31 and t32 and the approximate voltages at times t31 and t32.
- the temperature measurement accuracy can be improved by acquiring in advance the capacitance characteristic data indicating the relationship between the element capacitance C die of the power semiconductor element 10 and the gate-source voltage V gs . .
- the dependence on the gate-source voltage V gs has been shown above, the drain-source voltage V ds can also be corrected in the same way.
- Embodiment 7. 18 is a configuration diagram of a power module according to Embodiment 7.
- FIG. A semiconductor device 100 of a power module 101 of FIG. 18 differs from the semiconductor devices of the power modules of Embodiments 1 to 6 in that a differential voltmeter 52 is provided in place of the current detector 5 .
- Other configurations in FIG. 18 are the same as those in FIG. 1A and the like, so the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated.
- the voltage across the resistance element 8 is detected by the differential voltmeter 52 (eg instrumentation amplifier).
- the differential voltmeter 52 eg instrumentation amplifier
- an additional gate resistor may be provided in addition to the resistor element 8 in FIG. By doing so, it is possible to improve the degree of freedom of board wiring when fabricating the driver board.
- the temperature estimator 7 uses a value obtained by subtracting the value detected by the differential voltmeter 52 from the voltage detected by the voltage detector 6 as a voltage value. Calculate the resistance value using the current value. By doing so, the voltage drop due to the resistance element 8 can be removed, so that the temperature estimation accuracy can be improved.
- Embodiment 8 applies the power module 101 according to Embodiments 1 to 7 described above to a power converter. Although the present disclosure is not limited to a specific power converter, a case where the present disclosure is applied to a three-phase inverter will be described below as an eighth embodiment.
- FIG. 19 is a block diagram showing the configuration of a power conversion system to which the power conversion device according to this embodiment is applied.
- the power conversion system shown in FIG. 19 includes a power supply 120, a power conversion device 110, and a load 130.
- the power supply 120 is a DC power supply and supplies DC power to the power converter 110 .
- the power supply 120 can be composed of various things, for example, it can be composed of a DC system, a solar battery, a storage battery, or it can be composed of a rectifier circuit or an AC/DC converter connected to an AC system. good too.
- the power supply 120 may be configured by a DC/DC converter that converts the DC power output from the DC system into the set power.
- the power conversion device 110 is a three-phase inverter connected between the power supply 120 and the load 130 , converts the DC power supplied from the power supply 120 into AC power, and supplies the AC power to the load 130 .
- the power conversion device 110 includes a main conversion circuit 111 that converts DC power into AC power and outputs it, and a control circuit 112 that outputs a control signal for controlling the main conversion circuit 111 to the main conversion circuit 111.
- the load 130 is a three-phase electric motor driven by AC power supplied from the power converter 110 .
- the load 130 is not limited to a specific application, but is an electric motor mounted on various electrical equipment, such as a hybrid vehicle, an electric vehicle, a railway vehicle, an elevator, or an electric motor for air conditioning equipment.
- the main conversion circuit 111 includes a switching element and a freewheeling diode (not shown). By switching the switching element, the DC power supplied from the power supply 120 is converted into AC power and supplied to the load 130 .
- the main conversion circuit 111 is a two-level three-phase full bridge circuit, and has six switching elements and It can consist of six freewheeling diodes in anti-parallel. At least one of the switching elements of the main conversion circuit 111 is the power semiconductor element 10 included in the power module 101 of any one of the first to seventh embodiments described above.
- each upper and lower arm forms each phase (U phase, V phase, W phase) of the full bridge circuit.
- Output terminals of the upper and lower arms, that is, three output terminals of the main conversion circuit 111 are connected to the load 130 .
- the power module 101 includes the semiconductor device 100 (not shown) for driving each switching element. ing.
- the semiconductor device 100 generates a drive signal for driving the switching element of the main converter circuit 111 and supplies it to the control electrode of the switching element of the main converter circuit 111 .
- a drive signal for turning on the switching element and a drive signal for turning off the switching element are output to the control electrode of each switching element.
- the driving signal When maintaining the switching element in the ON state, the driving signal is a voltage signal (ON signal) equal to or higher than the threshold voltage of the switching element, and when maintaining the switching element in the OFF state, the driving signal is a voltage equal to or less than the threshold voltage of the switching element. signal (off signal).
- the control circuit 112 controls the switching elements of the main conversion circuit 111 so that the desired power is supplied to the load 130 . Specifically, based on the power to be supplied to the load 130, the time (on time) during which each switching element of the main conversion circuit 111 should be in the ON state is calculated. For example, the main conversion circuit 111 can be controlled by PWM control that modulates the ON time of the switching element according to the voltage to be output. Then, a control command (control signal ). The semiconductor device 100 outputs an ON signal or an OFF signal as a drive signal to the control electrode of each switching element according to this control signal.
- the power module 101 according to the first to seventh embodiments is applied as the power module 101 constituting the main conversion circuit 111, power conversion is performed based on the temperature measurement result of the power semiconductor element. Device reliability can be improved.
- the present disclosure is not limited to this, and can be applied to various power converters.
- a two-level power conversion device is used, but a three-level or multi-level power conversion device may be used. You can apply it.
- the present disclosure can be applied to a DC/DC converter or an AC/DC converter when power is supplied to a DC load or the like.
- the power conversion device to which the present disclosure is applied is not limited to the case where the above-described load is an electric motor. It can also be used as a power conditioner for a photovoltaic power generation system, an electric storage system, or the like.
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Abstract
Description
図1Aは、実施の形態1によるパワーモジュール101の一例を示す構成図である。図1Bは、図1Aの電流制御部1の構成例を示す回路図である。以下、図1Aおよび図1Bを参照して、パワーモジュール101の構成について説明する。
以下、図1Aの半導体装置100によるパワー半導体素子10の温度の推定方法についてより具体的に説明する。
ドライバ回路42は、パワー半導体素子10を駆動するために閾値電圧より大きい正電位Vccおよび閾値電圧以下の電位Vee(通常、負電位もしくはゼロ電位となる)を出力する。具体的に、ドライバ回路42は、主制御部41からの入力信号411に基づいて、パワー半導体素子10の制御端子Gに、ゲート電圧として正電位Vccまたは負もしくはゼロ電位Veeを印加する。
次に、温度計測を行う場合の半導体装置100の動作について説明する。温度計測は、ゲート電圧の立ち上がり期間および立ち下がり期間以外のゲート電圧が安定している期間で行われる。ゲート電圧が安定している期間には、ゲート電圧が正電位Vccで安定している期間(以下、「オン期間」と称する)と、ゲート電圧が負もしくはゼロ電位Veeで安定している期間(以下、「オフ期間」と称する)とがある。
次にオフ時間中での温度測定について説明する。図3の時刻t5で、ドライバ入力信号411がLレベルになってから、一定の遅延期間の経過後である時刻t6に、スイッチ制御信号31がLレベルに切り替わる。前述したように、この遅延時間は、簡単には、抵抗素子8の抵抗値とパワー半導体素子10の素子容量とからなる時定数、またはそれ以上の時間として設定することができる。この遅延時間が短いと、ドライバ回路42からのゲート駆動電流も電流検出部5によって検出されるため、温度測定の精度に影響を与える。
以上のように、本実施の形態のパワーモジュール101では、パワー半導体素子10のオン期間中またはオフ期間中に、電流源11からゲート電流Igを注入したときの電圧変化を測定することにより、パワー半導体素子10の温度を安定的に求めることができる。上記のゲート電流の注入開始のタイミングは、ドライバ電圧の立ち上がりや立下りタイミングから、簡単にはゲート抵抗と素子容量からなる時定数、またはそれ以上の時間として設定された遅延時間の経過後として定めることができる。
実際には、パワー半導体素子10のゲート容量Cdieは、パワー半導体素子10の端子電圧によって変化する。そこで、実施の形態2では、ゲート容量Cdieの変化の影響を抑制する方法について説明する。
以下、図5~図11Bを参照して、実施の形態3によるパワーモジュール101の半導体装置100の構成について説明する。実施の形態3のパワーモジュール101では、電流制御部1の構成が図1Aおよび図1Bの場合と異なり、より具体的に示されている。電流制御部1以外の点ついては、実施の形態3のパワーモジュール101の構成は実施の形態1および実施の形態2の場合と同様であるので、同一または相当する部分には同一の参照符号を付して説明を繰り返さない。なお、電流制御部1を構成する電流源11として、負荷に対して電流を供給するカレントソースを用いることもできるし、負荷から電流を吸収するカレントシンクを用いることもできる。
図5は、実施の形態3のパワーモジュールの第1の態様を示す構成図である。図5では、電流制御部1をパワー半導体素子10のソースS側に配置した場合の例を示す。この場合、電流制御部1の基準電位は、ドライバ回路42の制御グラウンド900である。したがって、電流源11および電流制御スイッチ12は、パワー半導体素子10の負極端子Sと制御グラウンド900との間に接続されている。
図6は、実施の形態3のパワーモジュールの第2の態様を示す構成図である。図6では、電流制御部1をパワー半導体素子10のゲート側に配置した場合の例を示す。図6の場合、電流源11にはカレントソースが用いられている。電流制御部1の基準電位は、ドライバ回路42の制御グラウンド900である。
図9は、実施の形態3のパワーモジュールの第3の態様を示す構成図である。図9では、電流制御部1をパワー半導体素子10のゲート側に配置した場合の例を示す。図9の場合、電流源11にはカレントソースまたカレントシンクを用いることができる。ドライバ回路42の基準電位901に関しては、図10Aおよび図10Bを参照して後述する。
実施の形態4では、パワー半導体素子10が並列に複数接続されている場合の例について説明する。以下では、3個のパワー半導体素子10A,10B,10Cが並列に接続されている場合について説明するが、並列接続されている複数のパワー半導体素子10は、3個に限定されない。なお、複数のパワー半導体素子10A,10B,10Cを総称する場合、または任意の1個を示す場合にパワー半導体素子10と記載する。
第一の方法は、図13に示すように、一つのスイッチングサイクル中に測定するゲート配線部2を切り替える方法である。図13では、オン期間中の測定方法について示しているが、オフ期間中においても同様に各パワー半導体素子10の温度を測定できる。
上記の第一の方法では、単一のスイッチングサイクルの中で複数回温度を測定するため、ゲート電圧の変動が大きく、パワー半導体素子10の損失が増加する可能性がある。この点を改良したものが、次の第二の方法である。
実施の形態5では、温度推定部7による温度推定方法の詳細について説明する。温度推定部7以外の点については、実施の形態1~4で説明したものと同様であるので説明を繰り返さない。また、以下では、パワー半導体素子10のオン期間中の温度測定について説明するが、オフ期間中の温度測定ついても同様である。
実施の形態6では、実施の形態5とは異なる手法を用いた温度推定部7による温度推定動作について説明する。温度推定部7以外の点については、実施の形態1~4で説明したものと同様であるので説明を繰り返さない。また、以下では、パワー半導体素子10のオン期間中の温度測定について説明するが、オフ期間中の温度測定ついても同様である。
図18は、実施の形態7によるパワーモジュールの構成図である。図18のパワーモジュール101の半導体装置100は、電流検出部5に代えて差動電圧計52が設けられている点で、実施の形態1~6のパワーモジュールの半導体装置と異なる。図18のその他の構成は、図1Aなどの場合と同様であるので、同一または相当する部分には同一の参照符号を付して説明を繰り返さない。
実施の形態8は、上述した実施の形態1~7にかかるパワーモジュール101を電力変換装置に適用したものである。本開示は特定の電力変換装置に限定されるものではないが、以下、実施の形態8として、三相のインバータに本開示を適用した場合について説明する。
Claims (14)
- 半導体素子を駆動制御する半導体装置であって、
前記半導体素子は、正極端子と、負極端子と、前記正極端子および前記負極端子間を流れる電流を制御する駆動電圧を供給するための制御端子とを有し、
前記半導体装置は、
前記制御端子と前記負極端子との間にパルス状の電流を流すために設けられたパルス電流源と、
前記制御端子に前記駆動電圧を供給することにより、前記半導体素子をオン状態およびオフ状態に遷移させる駆動制御部と、
前記パルス電流源によって前記半導体素子に流れる電流を検出する電流検出部と、
前記制御端子または前記負極端子と基準電位との間の電圧を検出する電圧検出部と、
前記電流検出部および前記電圧検出部の検出値に基づいて前記半導体素子の温度を推定する温度推定部と、
前記パルス電流源に電流を出力させるタイミングを制御するタイミング制御部とを備え、
前記タイミング制御部は、前記半導体素子が前記オン状態に遷移した後のオン期間中または前記オフ状態に遷移した後のオフ期間中に、前記パルス電流源に電流を出力させる、半導体装置。 - 前記タイミング制御部は、前記半導体素子が前記オン状態に遷移してから一定時間後、または前記半導体素子が前記オフ状態に遷移してから一定時間後に、前記パルス電流源に電流の出力を開始させる、請求項1に記載の半導体装置。
- 前記タイミング制御部は、前記パルス電流源に電流の出力を開始させてから、前記電流検出部によって検出された電圧の変化量が閾値を超えたときに、前記パルス電流源に電流の出力を終了させる、請求項1または2に記載の半導体装置。
- 前記半導体素子は、前記電流検出部による電流検出用の抵抗素子を有する、請求項1~3のいずれか1項に記載の半導体装置。
- 前記パルス電流源は、前記負極端子と前記基準電位との間に接続される、請求項1~4のいずれか1項に記載の半導体装置。
- 前記パルス電流源は、前記制御端子と前記基準電位との間に接続される、請求項1~4のいずれか1項に記載の半導体装置。
- 前記半導体素子は、第1の半導体素子であり、
前記半導体装置は、前記第1の半導体素子と並列に接続された第2の半導体素子をさらに駆動制御し、
前記半導体装置は、前記第1の半導体素子および前記第2の半導体素子と前記電流検出部との間の接続を切り替える切り替え回路をさらに備える、請求項1~6のいずれか1項に記載の半導体装置。 - 前記電流検出部は、前記負極端子に接続された配線に流れる電流を検出する、請求項1~7のいずれか1項に記載の半導体装置。
- 前記電流検出部は、前記制御端子に接続された配線に流れる電流を検出する、請求項1~7のいずれか1項に記載の半導体装置。
- 前記温度推定部は、前記パルス電流源から電流が出力されている期間の複数時点において、前記電流検出部および前記電圧検出部の検出値を取得する、請求項1~9のいずれか1項に記載の半導体装置。
- 前記温度推定部は、前記パルス電流源から電流の出力が開始されてから、前記電流検出部および前記電圧検出部による電流および電圧の検出時刻までの経過時間と、前記半導体素子の前記制御端子の入力容量の値とに基づいて、前記電流検出部および前記電圧検出部の検出値から計算した抵抗値を補正する、請求項1~9のいずれか1項に記載の半導体装置。
- 前記電流検出部は、
前記制御端子または前記負極端子に一端が接続された抵抗素子と、
前記抵抗素子に生じる電圧を検出する差動電圧計とを含む、請求項1~11のいずれか1項に記載の半導体装置。 - 前記温度推定部は、前記電圧検出部の検出値から前記差動電圧計の検出値を減算することにより得られた電圧値と、前記差動電圧計の検出値に基づく電流値とから抵抗値を計算する、請求項12に記載の半導体装置。
- 請求項1~13のいずれか1項に記載の半導体装置と半導体素子とを搭載した電力変換装置。
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