JP2003009509A - Intelligent power module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly reliable intelligent power module of a relatively simple structure. SOLUTION: This intelligent power module for controlling power in which a prescribed power semiconductor device incorporates a circuit for protecting the semiconductor device includes at least a pair of power semiconductor device connected in parallel with each other each of which has a diode connected in a forward direction from an emitter to a collector, circuit structures for detecting the semiconductor device current each of which is provided so as to correspond to each semiconductor device and has a shunt resistor connected to the emitter of the semiconductor device, and a synthesizing part which synthesizes current values detected by the respective circuit structures for detecting current and outputs it to a control circuit outside the module.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intelligent power module in which a predetermined power control power device is incorporated with a driver circuit and a protection circuit.

[0002]

2. Description of the Related Art In recent years, in home electric appliances and industrial equipment, a driver circuit and a protection circuit are incorporated in a power device such as a power MOSFET or an IGBT as an element for power control such as motor drive control and heater temperature control. Intelligent Power Module (Intelligent Power
Module: Hereinafter, demand for IPM) is increasing. The IPM usually has a self-protection function that protects built-in power devices by suppressing short-circuit current, overcurrent, control power supply, and overheat, and has a configuration that realizes that function compared to conventional modules that are externally attached. In addition to being easy to design, the module itself is resistant to breakage.

FIG. 7 shows an internal configuration of a conventionally known IPM for a motor drive inverter. This IPM80 uses an IGBT as an output terminal for driving a load.
IGBTs 81A and 81 in which two IGBTs (P-side IGBT and N-side IGBT, respectively) are connected in parallel
A pair of B, 82A and 82B, 83A and 83B is provided, and the output from each pair is connected to a three-phase induction motor 90 which is a control target. Also, each IGB on the P side and the N side
T has a free wheeling diode (Free Wheelin
g Diode: hereinafter referred to as FWDi) 87 is the IGBT
Is connected in a forward direction from the emitter to the collector. And N side IGBT81B, 82B, 83B
The shunt resistors 84 and 8 for current detection are provided on the emitter side of the
5,86 are connected. With this configuration, the IPM
When 80 is used, it is not necessary to attach a drive circuit or a protection circuit to the module main body, and the design can be facilitated.

By the way, when the load is limited to the compressor motor and there is almost no possibility that a ground fault will occur in the circuit, such as in an air conditioner, the protection circuit portion, that is, the shunt resistors 84, 85, 86 are installed. As shown in FIG. 7, the internal structure can be simplified by providing the N-side IGBTs 81B, 82B, and 83B only.

[0005]

However, the shunt resistances 84, 85, 86 are N-side IGBTs 81B, 82B, 83.
When connecting only to the emitter side of B, the internal structure can be simplified, but there are the following drawbacks. Since the gate voltage of the N-side IGBTs 81B, 82B, 83B is reduced by the amount of voltage drop of the shunt resistors 84, 85, 86, the saturation current characteristic of the IGBT is degraded. F
Shunt resistors 84 and 8 during recirculation in WDi87
Due to the voltage drop of 5,86, the VS potential of the IC in FIG.
There is a risk that the potential may drop below the potential and the IC may malfunction. Since the N side of the shunt resistors 84, 85, 86 of each phase is common, it is easily affected by noise during switching of other phases.
Since the current is detected by the shunt resistors 84, 85, 86 on the N side, the current flowing through the P side IGBTs 81A, 82A, 83A cannot be protected. When controlling a two-phase modulation or a DC brushless motor (hereinafter referred to as DCBLM), the N-side IGBTs 81B, 82B, 83B have a long off-time, and three-phase shunt resistors 84, 85, 86 are required. The points increase.

The present invention has been made in view of the above technical problems, and an object of the present invention is to provide an intelligent power module having a relatively simple structure and high reliability while realizing a simplified internal structure. To do.

[0007]

A first invention of the present application is a power control intelligent power module in which a circuit for protecting a semiconductor element is incorporated in a predetermined power semiconductor element. A pair of power semiconductor elements connected in parallel with each other, and a shunt resistor provided corresponding to each semiconductor element and connected to the emitter side of the semiconductor element. A semiconductor element current detection circuit configuration, and a synthesis unit that synthesizes the current values detected by the above current detection circuit configurations and outputs the synthesized current value to a control circuit outside the module. It is what

A second invention of the present application is the first invention according to the first invention, wherein a temperature detecting diode is provided on the emitter side of each of the semiconductor elements so as to be connected on the cathode side thereof, and each of the currents described above is provided. The detection circuit configuration is characterized in that a temperature detection diode is connected on the anode side thereof, and a correction circuit for correcting the temperature of the current detected by the shunt resistor is provided.

Further, the third invention of the present application is the first or second invention.
In the invention, the serial communication circuit unit for converting an input signal into serial digital data is provided on the output side of the synthesizing unit.

Further, the fourth invention of the present application is the first to the first inventions.
In any one of the third aspect of the present invention, in each of the current detection circuit configurations, the current detected by the shunt resistor is extracted based on a value after a predetermined time from its input. It is a thing.

[0011]

DETAILED DESCRIPTION OF THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings. Embodiment 1. FIG. 1 shows an I according to the first embodiment of the present invention.
It is a figure which shows the circuit structure for current detection of PM. This IP
M1 employs an IGBT as an output element for driving a load, and basically, P1s connected in parallel with each other.
Side and N side IGBTs 2A and 2B, and an I having an upper arm circuit configuration and a lower arm circuit configuration corresponding to each IGBT
C10 and. IGBT 2A on the P side and the N side,
FWDi 3A and 3B are both connected to 2B in a forward direction from the emitter to the collector of each IGBT.

The upper arm circuit configuration in the IC 10 is P side I
Shunt resistor 5A connected to the emitter side of GBT2A
An amplifier (denoted as AMP in the figure) 6A for amplifying the current detection value of the shunt resistor 5A, a gate driver (denoted as driver in the figure) 7A connected to the gate side of the P-side IGBT 2A, and an amplifier 6A The output is evaluated, and a protection circuit section 8A for turning off the gate driver 7A when the output exceeds a predetermined value, an A / D conversion section 9A for converting an analog signal from the amplifier 6A into a digital signal, and the A / D conversion. A pulse conversion unit 11A for converting a digital signal from the unit 9A into a current pulse train, and a level shift circuit unit (denoted as level shift in the figure) 12A for downshifting the output from the pulse conversion unit 11A to a low level reference potential. Have

On the other hand, the lower arm circuit configuration in the IC 10 includes a shunt resistor 5B connected to the emitter side of the N-side IGBT 2B, an amplifier 6B for amplifying a current detection value of the shunt resistor 5B, and an N-side IGBT 2B. The outputs from the gate driver 7B connected to the gate side and the amplifier 6B are evaluated, and if a predetermined value is exceeded, the gate driver 7B
And a pulse demodulator 13B for demodulating the pulse code modulated data from the level shift circuit 12A on the upper arm circuit side, and the pulse demodulator 1
It has a combiner 14B for combining the signal sent from the upper arm circuit configuration via 3B and the output from the amplifier 6B.

Further, in the IC 10, an input I / I is inputted to the lower arm circuit configuration side, to which the voltages VCIN (P) and VCIN (N) for the P-side and N-side IGBTs 2A and 2B are inputted.
An F section 15B and a pulse conversion section 11B for converting the output from the input I / F section 15B into a current pulse train are provided.
On the other hand, the pulse conversion unit 11B is provided on the upper arm circuit configuration side.
Level shift circuit section 16A for upshifting the output from the above to a high level reference potential, and pulse code modulation data from the level shift circuit section 16A are demodulated,
A pulse demodulation unit 13A for outputting to the protection circuit unit 8A is provided. The output from the input I / F unit 15B is
On the lower arm circuit configuration side, together with the pulse conversion unit 11B,
It is adapted to be input to the protection circuit section 8 and the combining section 14B.

In the IPM 1 having such a configuration, in both the upper arm circuit configuration and the lower arm circuit configuration, the voltage values amplified by the amplifiers 6A and 6B are the protection circuit portions 8A and 8A.
Input to the comparator in 8B. When the preset reference value is exceeded, the gate drivers 7A and 7B connected to the gates of the IGBTs 2A and 2B are turned off, and the IGBTs 2A and 2B are prevented from being destroyed by overcurrent.

Further, in this IPM1, each IGBT2
Current flowing through the sense terminals 2a and 2b of A and 2B (1 / 10,000 of the main current) based on the voltage across the shunt resistors 5A and 5B when flowing into the shunt resistors 5A and 5B. Is detected.

The current detection value detected in the upper arm circuit configuration is amplified by the amplifier 6A, and then the A / D converter 9
A, pulse converter 11A and level shift circuit 12A
And is input to the combining unit 14B on the lower arm circuit configuration side. On the other hand, the current detection value detected in the lower arm circuit configuration is amplified by the amplifier 6B and then input to the combining unit 14B.

The synthesizing unit 14B synthesizes the current detection value of the upper arm circuit configuration and the current detection value of the lower arm circuit configuration according to the input signal state of the input I / F unit 15B. Then, the current value VC synthesized by the synthesizer 14B is
It is output to an external control circuit (CPU or the like). In connection with this operation, FIG. 2 shows operation waveforms in each configuration of the IPM 1. 2A to 2F respectively show the input I
Voltage VC for P-side IGBT 2A input to the / F unit 15B
IN (P), N side IG input to the input I / F unit 15B
The waveforms of the BT2B voltage VCIN (N), the output current I ₀ , the detection voltage in the upper arm circuit configuration, the detection voltage in the lower arm circuit configuration, and the combined output are shown. As can be seen from this figure, P-side and N-side IGBTs 2A, 2B
The previous voltage value is held during a period in which both signals VCIN (P) and VCIN (N) for use are off (so-called dead time period).

With the above-described operation, the IPM 1 makes it possible to detect the current value flowing in a controlled object such as a motor without depending on the configuration arranged outside the module. Further, it is not necessary to incorporate a high-power resistor in the module, so that the module body can be downsized and the number of parts can be reduced. Further, it is possible to solve problems such as a decrease in gate voltage and a decrease in VS potential at the time of recirculation in the circuit configuration for current detection incorporated in the conventional module.

Next, another embodiment of the present invention will be described. Note that, in the following, the same components as those in the above-described embodiment will be denoted by the same reference numerals, and further description will be omitted. Embodiment 2. FIG. 3 shows the I according to the second embodiment of the present invention.
It is a figure which shows the circuit structure for current detection of PM. IPM2
1 has the same configuration as that of the first embodiment. In the second embodiment, the temperature detecting diodes 23A and 23B are further provided on the emitter side of each of the IGBTs 2A and 2B.
The correction circuits 25A, 2 are provided on the output side of the amplifiers 6A, 6B while being provided so as to be connected on the cathode side.
5B is provided. In addition, the correction circuits 25A and 25B
The temperature detecting diodes 23A and 23B are connected to the anode side thereof.

In the second embodiment, the temperature detecting diodes 23A and 23B and the correction circuits 25A and 25 are used.
By providing B, in addition to the effect described in the first embodiment, the temperature of the current detection voltage is corrected, and the current can be detected while suppressing the fluctuation due to temperature.

Embodiment 3. FIG. 4 is a diagram showing a circuit configuration for current detection of the IPM according to the third embodiment of the present invention. The IPM 31 has the same configuration as that of the first embodiment. In the third embodiment, the serial communication circuit section 33B is further provided on the output side of the combining section 14B on the lower arm circuit configuration side. When the voltage value output from the synthesizing unit 14B passes through the serial communication circuit unit 33B,
After being A / D converted into serial digital data, it is output to the outside of the module.

In the third embodiment, by providing the serial communication circuit section 33B, in addition to the effect described in the first embodiment, communication with the outside of the module can be digitized, and noise resistance is improved. It becomes possible. In addition, the module and external control circuit (CPU
Since the connection with (1) and the like) is digitized, the configurations of the I / F units of both can be simplified.

Fourth Embodiment FIG. 5 is a diagram showing operation waveforms of respective parts in the circuit configuration for current detection of the IPM according to the fourth embodiment of the present invention. (A) to (f) of FIG.
P-side IGB input to the input I / F unit 15B, respectively
T2A voltage VCIN (P), N-side IGBT2B voltage VCIN (N) input to input I / F unit 15B, output current I ₀ , detection voltage in upper arm circuit configuration, detection voltage in lower arm circuit configuration, combined Represents the output waveform.

FIG. 6 further shows shunt resistors 5A and 5B.
3 shows the relationship between the current value and the detected voltage at. In the fourth embodiment, a different method is used as the current detection method performed by the upper arm circuit configuration and the lower arm circuit configuration described in the first embodiment. In the first embodiment, the current is continuously detected, but in the fourth embodiment,
The voltage is detected based on the current value after a fixed time (“detection delay time” in the figure) from the rising edge of the input signal in the shunt resistors 5A and 5B, and the voltage value is held until the next detection. . The output value of the detected voltage is output as a stepped voltage value.

As can be seen from FIG. 6, in the upper arm circuit configuration and the lower arm circuit configuration, the shunt resistor 5 is used.
The current detected in A and 5B is extracted based on the value after a certain time from the input, so that the IG in the IPM
It is possible to avoid the influence of switching noise that may occur in BT, and it is possible to perform detection with high noise resistance.

Needless to say, the present invention is not limited to the illustrated embodiments, and various improvements and design changes can be made without departing from the gist of the present invention.

[0028]

According to the invention of claim 1 of the present application, in the intelligent power module for power control in which a circuit for protecting the semiconductor element is incorporated in a predetermined power semiconductor element, the forward direction is from the emitter to the collector. At least one pair of power semiconductor elements connected in parallel with each other, and a shunt resistor provided corresponding to each semiconductor element and connected to the emitter side of the semiconductor element. A semiconductor element current detection circuit configuration and a combination unit for combining the current values detected by each of the current detection circuit configurations and then outputting the combined current value to a control circuit outside the module are used. It is possible to detect the current value flowing in the controlled object such as, without depending on the configuration arranged outside the module. Further, it is not necessary to incorporate a large resistor having high power in the module, and it is possible to realize downsizing of the module body and reduction of the number of parts. Further, it is possible to solve problems such as a decrease in gate voltage and a decrease in VS potential at the time of recirculation in the circuit configuration for current detection incorporated in the conventional module.

Further, according to the invention of claim 2 of the present application, a temperature detecting diode is provided on the emitter side of each of the semiconductor elements so as to be connected on the cathode side thereof, and at the same time, for detecting each of the currents. Since the temperature detecting diode is connected to the anode side of the circuit configuration and a correction circuit for correcting the temperature of the current detected by the shunt resistor is provided, temperature correction of the current detection voltage is performed, It is possible to detect the current while suppressing fluctuation due to temperature.

Further, according to the invention of claim 3 of the present application, a serial communication circuit section for converting an input signal into serial digital data is provided on the output side of the synthesizing section. Communication can be digitized, and noise resistance can be improved.
Further, since the connection between the module and the external control circuit is digitized, the configuration of the I / F section of both can be simplified.

Further, according to the invention of claim 4 of the present application, in the circuit configuration for detecting each of the currents, the current detected by the shunt resistor is based on the value after a predetermined time from its input, IG included in IPM as it is extracted
It is possible to avoid the influence of switching noise that may occur in BT, and it is possible to perform detection with high noise resistance.

[Brief description of drawings]

FIG. 1 is a diagram showing a circuit configuration for current detection of a power module according to a first embodiment of the present invention.

FIG. 2A is a P-side IGBT input to an input I / F unit in the circuit configuration for current detection of the power module.
It is a figure which shows the waveform of the voltage VCIN (P) for T. (B) N-side IGBT voltage V input to the input I / F section in the current detection circuit configuration of the power module
It is a figure which shows the waveform of CIN (N). (C) is a diagram showing the waveform of the output current I ₀ of the circuit configuration of the current detection of the power module. (D) It is a figure which shows the waveform of the detection voltage in the upper arm in the circuit structure for current detection of the said power module. (E) It is a figure which shows the waveform of the detection voltage in the lower arm circuit structure in the circuit structure for current detection of the said power module. (F) It is a figure which shows the waveform of the synthetic | combination output in the circuit structure for the current detection of the said power module.

FIG. 3 is a diagram showing a circuit configuration for current detection of a power module according to a second embodiment of the present invention.

FIG. 4 is a diagram showing a circuit configuration for current detection of a power module according to a third embodiment of the present invention.

FIG. 5A is a diagram showing a waveform of a P-side IGBT voltage VCIN (P) input to the input I / F section in the circuit configuration for current detection of the power module according to the fourth embodiment of the present invention. is there. (B) N-side IGBT voltage V input to the input I / F section in the current detection circuit configuration of the power module
It is a figure which shows the waveform of CIN (N). (C) is a diagram showing the waveform of the output current I ₀ of the circuit configuration of the current detection of the power module. (D) It is a figure which shows the waveform of the detection voltage in the upper arm in the circuit structure for current detection of the said power module. (E) It is a figure which shows the waveform of the detection voltage in the lower arm circuit structure in the circuit structure for current detection of the said power module. (F) It is a figure which shows the waveform of the synthetic | combination output in the circuit structure for the current detection of the said power module.

FIG. 6 is a diagram showing the operation waveforms of FIG. 5 in more detail.

FIG. 7 is a diagram showing an internal configuration of a conventionally known power module.

[Explanation of symbols]

1 Intelligent power module, 2A, 2B
IGBT, 2a, 2b sense terminal, 3A, 3B freewheeling diode, 5A, 5B shunt resistor,
6A, 6B amplifier, 7A, 7B gate driver, 8
A, 8B protection circuit section, 14B combining section, 15B input I / F section, 23A, 23B temperature detecting diode, 2
5A, 25B correction circuit, 33B serial communication circuit section

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H03K 17/08 H03K 17/08 ZF term (reference) 5H007 AA12 CA01 CB05 FA03 FA06 FA13 5H740 BA13 BB05 MM08 MM12 5J055 AX15 AX32 AX37 AX44 AX64 BX16 CX07 CX20 DX09 DX59 DX84 EX02 EY01 EY12 EZ08 EZ09 EZ20 EZ23 EZ24 EZ61 FX04 FX13 FX18 FX32 GX02 GX04

Claims (4)

[Claims] 1. An intelligent power module for power control in which a circuit for protecting the semiconductor element is incorporated in a predetermined power semiconductor element, each including a diode connected in a forward direction from an emitter to a collector, At least a pair of power semiconductor elements connected in parallel, a circuit configuration for semiconductor element current detection, which is provided corresponding to each of the semiconductor elements and includes a shunt resistor connected to the emitter side of the semiconductor element, and An intelligent power module, characterized in that it has a combining section for combining the current values detected by the circuit configurations for detecting each current and then outputting the combined current value to a control circuit outside the module. 2. A temperature detecting diode is provided on the emitter side of each semiconductor element so as to be connected on the cathode side thereof, and a temperature detecting diode is included in the circuit configuration for detecting each current. The intelligent power module according to claim 1, further comprising a correction circuit that is connected on the anode side and that corrects the temperature of the current detected by the shunt resistor. 3. The serial communication circuit unit for converting an input signal into serial digital data is provided on the output side of the synthesizing unit.
Intelligent power module described in. 4. In the circuit configuration for detecting each current described above,
The intelligent power module according to any one of claims 1 to 3, wherein the current detected in the shunt resistor is extracted based on a value after a certain time has passed from its input.