JP2008154424A - Circuit module temperature calculation apparatus, and circuit module temperature calculation method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus and a method capable of rapidly and highly accurately obtaining a temperature at a temperature calculation point of an electric circuit module. <P>SOLUTION: The circuit module temperature calculation apparatus includes: a self-function circuit having a value based on the self-temperature function as an input immittance; a self-power source for outputting electric power, which equivalently displays the heat energy provided to the temperature calculation point, to the input terminal of the self-function circuit; a mutual function circuit having a value based on the mutual temperature function, as the input immittance, which displays a responsive characteristic of the temperature calculation point relative to the heat energy provided to the separation point away from the temperature calculation point; a mutual power source for outputting electric power, which equivalently displays the heat energy provided to the separation point, to the input terminal of the mutual function circuit; and a temperature calculation section which obtains a temperature at the temperature calculation point based on a synthetic value obtained by synthesizing a value of electric physical quantity appearing at the input terminal of the self-function circuit and a value of the electric physical quantity appearing at the input terminal of the mutual-function circuit. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an apparatus and a method for calculating a temperature at a temperature calculation point included in an electric circuit module based on thermal energy generated in the electric circuit module.

  An electric circuit module for controlling the motor generator is used for a vehicle that is driven by the motor generator. The electric circuit module includes a step-up / step-down converter circuit that steps up and down a voltage, an inverter circuit that converts a DC voltage into an AC voltage, and converts the AC voltage into a DC voltage. In general, such an electric circuit module generates a large amount of heat because it processes electric power necessary to drive the vehicle by a motor generator.

T. Kojima et al. "Novel Electro-Thermal Coupling Simulation Technique for Dynamic Analysis of HV Inverter", 2006 PESC, pp.2048-2052 Allen R. Hefner "A Dynamic Electro-Thermal Model for the IGBT", 1992 IEEE Industry Application Society Annual Meeting, pp. 1094-1104

  Heat generation of the electric circuit module is a cause of shortening its life. Therefore, it is necessary to take measures for avoiding a temperature rise for an electric circuit module having a large calorific value. Therefore, it is conceivable to calculate the temperature distribution in a state where the electric circuit module is operating, and to apply the calculation result to a measure for avoiding the temperature rise.

  The present invention has been made for such a problem, and is a circuit module temperature calculation device capable of quickly and accurately obtaining the temperature at the temperature calculation point of the electric circuit module, and the temperature of the electric circuit module. Provided is a method for acquiring a temperature at a calculation point quickly and with high accuracy.

  The circuit module temperature calculation apparatus according to the present invention uses, as an input immittance, a value based on a self-temperature function indicating a response characteristic of the temperature calculation point with respect to thermal energy given to the temperature calculation point which is a point included in the electric circuit module. A self-function circuit having a self-power source that outputs to the input terminal of the self-function circuit an electric power equivalent to the thermal energy given to the temperature calculation point; and included in the electric circuit module separated from the temperature calculation point A mutual function circuit having a value based on a mutual temperature function indicating a response characteristic of the temperature calculation point with respect to the thermal energy given to the isolation point as an input immittance, and equivalent to the thermal energy given to the isolation point Appearing at the input terminal of the self-function circuit and the mutual power source that outputs the power shown in FIG. A measuring unit for measuring a physical quantity and an electrical physical quantity appearing at an input terminal of the mutual function circuit; a value of an electrical physical quantity appearing at an input terminal of the self-function circuit when the self-power source outputs power; and the mutual power A temperature calculation unit for obtaining a temperature at the temperature calculation point based on a synthesized value obtained by synthesizing a value of an electrophysical quantity that appears at an input terminal of the mutual function circuit when the source outputs power; It is characterized by.

  In the circuit module temperature calculation apparatus according to the present invention, the self-temperature function and the mutual temperature function are functions with respect to time, and the self-function circuit sets a time change rate of the self-temperature function to a predetermined scaling constant. Including a passive element whose element constant is determined so as to have an input immittance as a value derived from the function derived by doubling, wherein the mutual function circuit has a time change rate of the mutual temperature function as the scaling constant multiple. It is preferable to include a passive element whose element constant is determined so as to have the value indicated by the function derived from the above as an input immittance.

  The circuit module temperature calculation method according to the present invention inputs a value based on a self-temperature function indicating a response characteristic of the temperature calculation point with respect to thermal energy given to the temperature calculation point which is a point included in the electric circuit module. A step of inputting power equivalently indicating thermal energy given to the temperature calculation point to the self-function circuit having immittance, and a separation point that is separated from the temperature calculation point and included in the electric circuit module A mutual function circuit having a value based on a mutual temperature function indicating a response characteristic of the temperature calculation point with respect to the obtained thermal energy as an input immittance, and an electric power equivalently indicating the thermal energy given to the isolation point in the mutual function circuit Input to the input terminal of the self-function circuit, the electrical physical quantity appearing at the input terminal of the self-function circuit, and the correlation Measuring an electrophysical quantity appearing at the input terminal of the circuit, and combining the value of the electrophysical quantity appearing at the input terminal of the self-function circuit and the value of the electrophysical quantity appearing at the input terminal of the mutual function circuit. The temperature at the temperature calculation point is obtained based on the synthesized value obtained in this manner.

  Immitance is a general term for impedance and admittance.

  According to the present invention, the temperature at the temperature calculation point of the electric circuit module can be acquired quickly and with high accuracy.

  FIG. 1 shows a vehicle drive system according to an embodiment of the present invention. The vehicle drive system includes a power circuit 10, a motor generator 14, a current sensor 16, a rotation speed sensor 18, an operation unit 20, a control unit 22, and a circuit module temperature calculation device 24. The vehicle drive system is mounted on the vehicle, and the vehicle is driven by the motor generator 14. Further, the electric power generated by the motor generator 14 by the traveling of the vehicle is collected in the power circuit 10.

  The power circuit 10 outputs power to the motor generator 14 based on the control of the control unit 22, or collects the power generated by the motor generator 14 based on the control of the control unit 22. The power exchanged between the power circuit 10 and the motor generator 14 is adjusted by the control unit 22 controlling the power circuit 10.

  The power circuit 10 includes an electric circuit module 12 including element circuits E1 to Em. m is a natural number indicating the number of element circuits. The element circuits E1 to Em are controlled by the control unit 22. The element circuits E1 to Em include a step-up / down converter circuit that adjusts a voltage output to the motor generator 14, a three-phase AC voltage generated by the motor generator 14 by converting the DC voltage into a three-phase AC voltage output to the motor generator 14. An inverter circuit or the like that converts DC to DC voltage is applied. Adjustment of the electric power exchanged with the motor generator 14 is performed by control of the element circuits E1-Em.

  N temperature calculation points P1 to Pn to be subjected to temperature calculation are defined inside or on the surface of the electric circuit module 12. However, n is a natural number indicating the number of temperature calculation points. Here, the number n of temperature calculation points is assumed to be equal to the number m of element circuits, and the positions of temperature calculation points P1 to Pn are set to positions where the element circuits E1 to Em are provided.

  The motor generator 14 rotates based on the power acquired from the power circuit 10 and drives the vehicle. Further, the power generated by the traveling of the vehicle is output to the power circuit 10.

  The current sensor 16 measures a current flowing through a conducting wire provided for transferring power between the power circuit 10 and the motor generator 14 and outputs the measurement result to the control unit 22 as a current measurement value.

  The rotation speed sensor 18 measures the rotation speed per unit time of the motor generator 14 and outputs the measurement result to the control unit 22 as a rotation speed measurement value.

  The operation unit 20 includes an accelerator pedal, a brake pedal, a change lever, and the like. Control unit 22 controls power circuit 10 based on the current measurement value and the rotation speed measurement value so that the vehicle is in a traveling state according to the operation of operation unit 20.

  The circuit module temperature calculation device 24 includes a self-function circuit SCii (i is a natural number of 1 to n), a mutual function circuit MCik (k is a natural number of 1 to n different from i), a constant current source J11 to Jnn, and a voltmeter V11. -Vnn, addition total part (SIGMA) 1-Σ, grounding conductor 26, temperature calculation control part 28, and memory | storage part 30 are comprised.

  One terminal of each of the self-function circuit SCii, the mutual function circuit MCik, the constant current sources J11 to Jnn, and the voltmeters V11 to Vnn is connected to the ground conductor 26.

  The terminal TPii on the side not connected to the ground conductor 26 of the self-function circuit SCii is a terminal on the side not connected to the ground conductor 26 of the constant current source Jii and the side not connected to the ground conductor 26 of the voltmeter Vii. Connected to the terminal.

  The terminal TPik on the side not connected to the ground conductor 26 of the mutual function circuit MCik is the terminal on the side not connected to the ground conductor 26 of the constant current source Jik and the side not connected to the ground conductor 26 of the voltmeter Vik. Connected to the terminal.

  The constant current source Jii outputs the current set by the control of the temperature calculation control unit 28 to the terminal TPii. The constant current source Jik outputs the current set by the control of the temperature calculation control unit 28 to the terminal TPik.

  FIG. 2A shows a configuration example of the self-function circuit SCii. The self-function circuit SCii is a circuit in which p unit elements CR1 to CRp each formed by a resistance element and a capacitor connected in parallel are connected in series (p is an arbitrary natural number). The unit elements CR1 to CRp include resistance elements R1 to Rp, respectively, and the resistance elements R1 to Rp may have different resistance values. The unit elements CR1 to CRp include capacitors C1 to Cp, respectively, and the capacitors C1 to Cp can have different capacitances. The mutual function circuit MCik has a configuration similar to that of the self-function circuit SCii, and includes unit elements connected in series. The self-function circuits SC11, SC22,..., SCnn and the mutual function circuits MC12, MC13,..., MCnn-1 can have different numbers of unit elements and have different element constants. And a capacitor.

  Here, a description will be given of a method for determining the element constants of each resistive element and each capacitor constituting the self-function circuit SCii and the element constants of each resistive element and each capacitor constituting the mutual function circuit MCik.

  The respective temperatures Th1 to Thn of the temperature calculation points P1 to Pn are expressed as the following (formula 1) by the heat energy H1 to Hn and the heat transfer function matrix [F] given to the temperature calculation points P1 to Pn, respectively. Is done. However, (Formula 1) is an expression in the complex frequency domain, and s indicates a complex frequency variable.

  The element Fii (s) of the heat transfer function matrix [F] is a self-temperature function indicating the frequency response characteristic of the temperature at the temperature calculation point Pi with respect to the thermal energy Hi given to the temperature calculation point Pi. The element Fik (s) of the matrix [F] is a mutual temperature function indicating the frequency response characteristic of the temperature at the temperature calculation point Pi with respect to the thermal energy Hk given to the temperature calculation point Pk.

  Further, (Expression 2) represents (Expression 1) in the time domain. t is a time variable and τ is an integral variable of convolution integral. The integral symbol means that an integral operation is performed on each element of the matrix. The temperatures th1 to thn are the temperatures Th1 to Thn expressed in the time domain, respectively. Thermal energies h1 to hn represent thermal energies H1 to Hn in the time domain, respectively. The heat transfer function matrix [f] represents the heat transfer function matrix [F] in the time domain.

  The element fii (t) of the heat transfer function matrix [f] is a self-temperature function indicating the impulse response characteristic of the temperature at the temperature calculation point Pi with respect to the heat energy given to the temperature calculation point Pi, and the heat transfer function matrix The element fik (t) of [f] is a mutual temperature function indicating an impulse response characteristic of the temperature at the temperature calculation point Pi with respect to the thermal energy given to the temperature calculation point Pk.

  Each element of the heat transfer function matrix [f] includes temperature calculation points P1 to P1 when thermal energy whose time waveform is represented by an impulse function is given to any one of the temperature calculation points P1 to Pn. It can be obtained by observing the time response waveform of the temperature in each of Pn. In addition, by obtaining in advance the characteristics of the material constituting the electric circuit module 12, the heat transfer function matrix [F] or [f] can be obtained by computer simulation.

  A circuit having the same admittance as the value of each element of the heat transfer function matrix [F] can be realized by a circuit including a resistance element and a capacitor. This point is described in Non-Patent Document 1.

  For example, when the element Fik (s) of the heat transfer function matrix [F] in the complex frequency domain is expressed as 1 / (1 / (A + sB) + 1 / (D + sQ)), the element Fik (s) A circuit having the same admittance as the value includes a first unit element EL1 including a resistance element having a resistance value of 1 / A and a capacitor having a capacitance of B, and a resistance having a resistance value of 1 / D. A circuit as shown in FIG. 3 is obtained by connecting in series a second unit element EL2 composed of an element and a capacitor having a capacitance of Q. The example is shown by the expression in the complex frequency domain because it is easy to explain by the AC network theory. Here, the resistance element means that the heat energy given to the temperature calculation point Pk is released from the electric circuit module 12 to the outside at the temperature calculation point Pi, and the capacitor has the heat at the temperature calculation point Pi. It means to be accumulated.

  In determining the number of unit elements CR included in the self-function circuit SCii and the element constants of each resistance element and each capacitor included in the self-function circuit SCii, first, the temperature calculation of any one of the temperature calculation points P1 to Pn is performed. Thermal energy represented by a step function (a function whose value is zero before a certain time t0 and rises to a predetermined value after time t0) is given to the point Pk, and the time of temperature at the temperature calculation points P1 to Pn Response waveforms are acquired as temperature calculation point response waveforms g1k (t) to gnk (t), respectively. This is performed for all k = 1 to n, and data of temperature calculation point response waveforms g11 (t) to gnn (t) is acquired.

  The number of unit elements CR included in the self-function circuit SCii, and the element constants of each resistance element and each capacitor included in the self-function circuit SCii are the temperature calculation point response waveform gii (t) and the step current as the self-function circuit SCii. And the time waveform of the response voltage appearing at the terminal TPii when it is input from the terminal TPii is determined to match. Here, the step current refers to a current whose time waveform is represented by a step function. Similarly, the number of unit elements included in the mutual function circuit MCik, and the element constants of the respective resistance elements and capacitors included in the mutual function circuit MCik are the temperature calculation point response waveforms gik (t ) And the time waveform of the response voltage appearing at the terminal TPik when the step current is input to the terminal TPik of the mutual function circuit MCik. Such element constants can be determined by actual measurement or electric circuit simulation.

  Note that, here, the self-function circuit SCii and the mutual function circuit MCik are described as an example constituted by unit elements CR1 to CRp connected in series. In addition to such a configuration, the resistance elements R1 to Rp connected in series, and the capacitors C1 to Cp connected between the terminals on the constant current source side of the resistance elements R1 to Rp and the ground conductor 26, respectively. It is also possible to configure the self-function circuit SCii and the mutual function circuit MCik with a ladder type RC circuit as shown in FIG. The ladder stage number p and the element constants of the resistance elements R1 to Rp and the capacitors C1 to Cp are similar to the configuration of the unit elements CR1 to CRp, and the temperature calculation point response waveforms g11 (t) to gnn (t) and the self-function circuit And the time waveform of the response voltage at each terminal of the mutual function circuit.

  Next, a process in which the circuit module temperature calculation device 24 calculates the temperatures of the temperature measurement points P1 to Pn will be described.

  The temperature calculation control unit 28 acquires information on the current measurement value, the rotation speed measurement value, and the control state of the power circuit 10 from the control unit 22. The information related to the control state of the power circuit 10 includes, for example, information related to the boost ratio of the buck-boost converter circuit, the frequency of the voltage output from the inverter circuit, and the like.

  The operating states of the element circuits E1 to Em included in the electric circuit module 12 depend on the control state of the motor generator 14 determined by the current flowing through the motor generator 14, the number of revolutions per unit time of the motor generator 14, the control state of the power circuit 10, and the like. Different. That is, some of the element circuits E1 to Em generate heat when they are in an operating state, and some are not operating and generate heat. Further, depending on the control state of the motor generator 14, there is a difference in the magnitude of heat generated between the plurality of element circuits in the operating state.

  Therefore, in the present embodiment, information for determining the control state of the motor generator 14 such as the current flowing through the motor generator 14, the number of revolutions per unit time of the motor generator 14, the control state of the power circuit 10, and the temperature calculation points P1 to Pn. A heat source distribution table showing a correspondence relationship between the values of the heat energy generated in step 1 is acquired in advance by actual measurement or the like and stored in the storage unit 30.

  The temperature calculation control unit 28 stores, in the storage unit 30, values of thermal energy generated at the temperature calculation points P <b> 1 to Pn corresponding to information on the current measurement value, the rotation speed measurement value, and the control state of the power circuit 10. Obtained by referring to the heat source distribution table. And based on the acquired value, the electric current which the constant current sources J11-Jnn should output is determined, and the constant current sources J11-Jnn are controlled so that the determined electric current is output.

  The voltmeters V11 to V1n measure voltages between the terminals TP11 to TP1n and the ground conductor 26, respectively, and output the measurement results as voltage measurement values MV11 to MV1n, respectively, to the summation unit Σ1. Similarly, the voltmeters V21 to V2n measure the voltages between the terminals TP21 to TP2n and the ground conductor 26, respectively, and output the measurement results as voltage measurement values MV21 to MV2n, respectively, to the summation unit Σ2. That is, the voltmeters Vi1 to Vin measure the voltages between the terminals TPi1 to TPin and the ground conductor 26, respectively, and output the measurement results as voltage measurement values MVi1 to MVin, respectively, to the summation unit Σi.

  The addition summation unit Σi calculates an addition total value of the voltage measurement values MVi1 to MVin, and outputs it to the temperature calculation control unit 28 as the temperature instruction voltage Ti. Temperature instruction voltages T1 to Tn equivalently indicate temperatures at temperature calculation points P1 to Pn, respectively. The temperature calculation control unit 28 outputs the temperature instruction voltages T <b> 1 to Tn to the control unit 22 and the storage unit 30.

  The control unit 22 controls the power circuit 10 based on the temperature instruction voltages T1 to Tn. For example, when there is a temperature command voltage T1 to Tn that exceeds a threshold value determined for each of the temperature command voltages T1 to Tn, the current that flows in the element circuit that exists at the temperature calculation point corresponding to the temperature command voltage that exceeds the threshold value The power circuit 10 is controlled so as to be limited. Alternatively, the power circuit 10 may be controlled so that the power exchanged between the power circuit 10 and the motor generator 14 is reduced.

  The storage unit 30 stores temperature instruction voltages T1 to Tn. The stored temperature instruction voltages T1 to Tn can be read out by a predetermined device and can be applied to maintenance and inspection.

  According to the vehicle drive system according to the present embodiment, not only the contribution of thermal energy generated at the temperature calculation point to be subjected to temperature calculation, but also the thermal energy exchanged with other temperature calculation points is considered. Thus, the temperature at each temperature calculation point is calculated. Thereby, the temperature at each temperature calculation point can be calculated with high accuracy.

  Further, the temperature is calculated by a hardware circuit using the self-function circuit SCii and the mutual function circuit MCik whose element constants are determined based on the temperature calculation point response waveforms g11 (t) to gnn (t) acquired in advance. This is done by actually measuring the response voltage. Thus, the temperature at each temperature calculation point can be calculated in a shorter time than a method based on numerical calculation using the heat transfer function matrix [f].

  Generally, when the temperature at each temperature calculation point is obtained by numerical calculation based on (Equation 2), it takes a long time for the integral calculation to converge. Therefore, in a vehicle drive system in which the value of thermal energy generated at each temperature calculation point changes sharply according to the running state of the vehicle, the temperature at each temperature calculation point is calculated by numerical calculation based on (Equation 2). It is difficult. According to the circuit module temperature calculation device 24 according to the present embodiment, the temperature at each temperature calculation point can be calculated in a short time.

  Next, a modification of the module temperature calculation device 24 will be described. FIG. 4 shows the configuration of a vehicle drive system to which the circuit module temperature calculation device 24A is applied. The circuit module temperature calculation device 24A includes a temperature calculation control unit 28, a self-function circuit SCii, and a mutual function circuit MCik included in the circuit module temperature calculation device 24, respectively, a temperature calculation control unit 28A, a post-scaling self-function circuit SAii, and a post-scaling circuit. It is replaced with the mutual function circuit MAik. The same components as those of the module temperature calculation device 24 are denoted by the same reference numerals and description thereof is omitted.

  FIG. 5A shows the configuration of the scaled self-function circuit SAii. Similar to the self-function circuit SCii, the post-scaling self-function circuit SAii is formed by connecting p unit elements U1 to Up each composed of a resistance element and a capacitor connected in parallel. Similar to the self-function circuit SCii, the post-scaling self-function circuit SAii can also be configured by a ladder-type RC circuit shown in FIG. Further, the post-scaling mutual function circuit MAik has the same configuration as the post-scaling self-function circuit SAii.

  The element constants of each resistance element and each capacitor of the post-scaling self-function circuit SAii are determined based on a temperature calculation point response waveform gii (at) obtained by multiplying the time change rate of the temperature calculation point response waveform gii (t) by a scaling constant a. To do. The element constants of the resistance elements and the capacitors of the scaled mutual function circuit MAik are based on a temperature calculation point response waveform gik (at) obtained by multiplying the time change rate of the temperature calculation point response waveform gik (t) by a scaling constant a. To decide.

  The resistance value of each resistance element and the capacitance of each capacitor in the post-scaling self-function circuit SAii are 1 / √ for each resistance value and each capacitance determined based on the temperature calculation point response waveform gii (t). a times. Similarly, the resistance value of each resistance element and the capacitance of each capacitor of the scaled mutual function circuit MAik are the resistance value and each capacitance determined based on the temperature calculation point response waveform gik (t), respectively. 1 / √a times.

  That is, the resistance value of each resistance element and the capacitance of each capacitor of the scaled self-function circuit SAii are each 1 / √a times the resistance value of each resistance element of the self-function circuit SCii and the capacitance of each capacitor. The resistance value of each resistance element and the capacitance of each capacitor of the scaled mutual function circuit MAik are 1 / √a times the resistance value of each resistance element of the mutual function circuit MCik and the capacitance of each capacitor, respectively. Will be.

  The temperature calculation control unit 28A acquires the values output from the addition summation units Σ1 to Σn as the scaled temperature instruction voltages TS1 to TSn, respectively. The temperature calculation control unit 28A multiplies the time change rate of the scaled temperature instruction voltages TS1 to TSn by 1 / a, and outputs them as the temperature instruction voltages T1 to Tn to the control unit 22 and the storage unit 32, respectively.

  By determining the element constant in this way, the time change rate of the post-scaling temperature instruction voltages TS1 to TSn becomes the scaling constant a times the time change rate of the temperature instruction voltages T1 to Tn. Therefore, if the scaling constant is made larger than 1, the time change of the temperature indication voltages TS1 to TSn after scaling can be made steep, and the temperature after scaling after the constant current sources J11 to Jnn output a current of a predetermined value. The time until the values of the command voltages TS1 to TSn converge can be shortened. Thereby, the temperature instruction voltages T1 to Tn can be calculated quickly.

  The circuit module temperature calculation apparatus according to the embodiment of the present invention can be applied to the calculation of the temperature distribution of not only the electric circuit module 12 applied to the vehicle drive system but also a general electric circuit module. FIG. 6 shows a configuration of an electric circuit system to which the circuit module temperature calculation apparatus according to the embodiment of the present invention is applied. The same components as those of the vehicle drive system in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted.

  The electric circuit system includes a control unit 22, an electric circuit module 34, and a circuit module temperature calculation device 36. The circuit module temperature calculation device 36 is a circuit module temperature calculation device 24 provided with a display unit 32. Instead of the circuit module temperature calculation device 24, a display unit 32 may be provided in the circuit module temperature calculation device 24A.

  The element circuits E <b> 1 to Em included in the electric circuit module 34 are controlled by the control unit 22 to be in either an operating state or a non-operating state.

  The control unit 22 outputs operation information for identifying the element circuit that is controlled to be in the operation state to the temperature calculation control unit 28.

  The storage unit 30 stores a heat source distribution table in which information for identifying an element circuit is associated with heat energy generated when the element circuit is in an operating state. This heat source distribution table is acquired in advance by actual measurement. For example, when the element circuit E2 is in an operating state, predetermined heat energy is generated at the temperature measurement point P2 depending on the operation, and therefore the value of the predetermined heat energy is used as information for identifying the element circuit E2. You can associate them with a table.

  The temperature calculation control unit 28 obtains a value of thermal energy generated at each temperature calculation point based on the operation information acquired from the control unit 22 and the heat source distribution table stored in the storage unit 30. Then, the currents to be output by the constant current sources J11 to Jnn are determined based on the obtained thermal energy values, and the constant current sources J11 to Jnn are controlled so that the determined currents are output. By such control, the constant current source corresponding to the element circuit in the operating state outputs a current determined based on the value of the thermal energy obtained based on the heat source distribution table, and the element circuit in the non-operating state No current is output from the constant current source corresponding to.

  The temperature calculation control unit 28 outputs the temperature instruction voltages T1 to Tn acquired from the summation units Σ1 to Σn to the display unit 32 and the storage unit 30, respectively. The display unit 32 displays the temperatures of the temperature calculation points P1 to Pn based on the temperature instruction voltages T1 to Tn. Further, the temperature instruction voltages T1 to Tn stored in the storage unit 30 can be read out by a predetermined device.

  According to the electric circuit system according to the present embodiment, the temperatures of the temperature calculation points P1 to Pn of the electric circuit module 34 can be calculated quickly. The calculated temperatures of the temperature calculation points P1 to Pn can be used for heat dissipation design when the electric circuit module 34 is mounted on the system. Further, based on the temperature of the temperature calculation points P1 to Pn, it is possible to perform adaptive control as to whether or not to put each element circuit into an operating state, and the life of the electric circuit module 34 due to the high temperature is increased. Shortening can be avoided.

  In the above-described embodiment, the number n of temperature calculation points is equal to the number m of element circuits, and the positions of temperature calculation points P1 to Pn are set to positions where the element circuits E1 to Em are provided, respectively. . However, the number n of temperature calculation points and the number m of element circuits do not necessarily have to be the same, and the temperature calculation points P1 to Pn can be defined at arbitrary positions inside or on the surface of the electric circuit module. In this case, a heat source distribution table may be acquired in advance based on the temperature calculation points defined in this manner and stored in the storage unit 30.

  Further, the circuit module temperature calculation devices 24, 24A and 36 input currents to the terminals TP11 to TPnn by a constant current source, and equivalently indicate the temperature at each temperature calculation point based on the voltage appearing at the terminals TP11 to TPnn. The value is acquired. In addition to such a configuration, a voltage is applied to the terminals TP11 to TPnn by a constant voltage source, and a value that equivalently indicates the temperature at each temperature calculation point is acquired based on the current flowing into the terminals TP11 to TPnn. It is also possible.

  In this case, the self-function circuit and the mutual function circuit are circuits shown in FIG. 7A in which unit elements LR1 to LRp each constituted by an inductor and a resistance element connected in series are connected in parallel (FIG. 2A). Dual circuit). Unit elements LR1 to LRp include inductors L1 to Lp and resistance elements R1 to Rp, respectively. The self-function circuit and the mutual function circuit include the inductors L1 to Lp connected in series, and the resistance elements R1 connected between the terminals on the constant voltage source side of the inductors L1 to Lp and the ground conductor 26, respectively. It is also possible to configure a ladder type RL circuit (a dual circuit of the circuit of FIG. 2B) as shown in FIG. When the time change rate of the temperature calculation point response waveforms g11 (t) to gnn (t) is configured to be multiplied by the scaling constant a, the inductance values of the inductors L1 to Lp are each 1 / √a times and the resistance element R1. Each resistance value of ~ Rp may be set to √a.

It is a figure which shows a vehicle drive system. It is a figure which shows the structure of a self-function circuit and a mutual function circuit. It is a figure which shows the example of the circuit which has the same admittance as the value of element Fik (s) of heat transfer function matrix [F]. It is a figure which shows the vehicle drive system which deform | transformed the circuit module temperature calculation apparatus. It is a figure which shows the structure of the self-function circuit after scaling, and the mutual function circuit after scaling. It is a figure which shows an electric circuit system. It is a figure which shows the structure of the self-function circuit comprised by an inductor and a resistive element, and a mutual function circuit.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Power circuit, 12, 34 Electrical circuit module, 14 Motor generator, 16 Current sensor, 18 Rotational speed sensor, 20 Operation part, 22 Control part, 24, 24A, 36 Circuit module temperature calculation apparatus, 26 Ground conductor, 28 Temperature calculation Control unit, 30 storage unit, 32 display unit, SCii self-function circuit, MCik mutual function circuit, J11 to Jnn constant current source, V11 to Vnn voltmeter, Σ1 to n addition and total unit, P1 to Pn temperature calculation point, E1 to Em element circuit, CR1-CRp, EL1, EL2, U1-Up, LR1-LRp unit element, R1-Rp resistance element, C1-Cp capacitor, L1-Lp inductor.

Claims (3)

A self-function circuit having, as an input immittance, a value based on a self-temperature function indicating a response characteristic of the temperature calculation point to the thermal energy given to the temperature calculation point which is a point included in the electric circuit module;
A self-power source that outputs, to the input terminal of the self-function circuit, electric power equivalently representing thermal energy given to the temperature calculation point;
A mutual function circuit having, as an input immittance, a value based on a mutual temperature function indicating a response characteristic of the temperature calculation point to thermal energy applied to an isolation point that is separated from the temperature calculation point and included in the electrical circuit module When,
A mutual power source that outputs, to the input terminal of the mutual function circuit, an electric power equivalent to the thermal energy given to the isolation point;
A measurement unit for measuring an electrophysical quantity appearing at an input terminal of the self-function circuit and an electrophysical quantity appearing at an input terminal of the mutual function circuit;
The value of the electrophysical quantity that appears at the input terminal of the self-function circuit when the self-power source outputs power, and the value of the electrophysical quantity that appears at the input terminal of the mutual function circuit when the mutual power source outputs power And a temperature calculation unit for obtaining a temperature at the temperature calculation point based on a combined value obtained by combining
A circuit module temperature calculation device comprising: The circuit module temperature calculation device according to claim 1,
The self-temperature function and the mutual temperature function are functions with respect to time;
The self-function circuit includes a passive element whose element constant is determined so as to have, as an input immittance, a function derived by multiplying a time change rate of the self-temperature function by a predetermined scaling constant,
The mutual function circuit includes a passive element whose element constant is determined so as to have, as an input immittance, a value derived from a function derived by multiplying a time change rate of the mutual temperature function by the scaling constant multiple. Circuit module temperature calculation device. A self-function circuit having a value based on a self-temperature function indicating a response characteristic of the temperature calculation point with respect to thermal energy given to the temperature calculation point, which is a point included in the electric circuit module, as an input immittance. Inputting power that is equivalent to given thermal energy;
A mutual function circuit having, as an input immittance, a value based on a mutual temperature function indicating a response characteristic of the temperature calculation point to thermal energy applied to an isolation point that is separated from the temperature calculation point and included in the electrical circuit module A step of inputting, to the input terminal of the mutual function circuit, electric power equivalently indicating the thermal energy given to the isolation point;
Measuring an electrophysical quantity appearing at an input terminal of the self-function circuit and an electrophysical quantity appearing at an input terminal of the mutual function circuit;
Including
Obtaining a temperature at the temperature calculation point based on a synthesized value obtained by synthesizing the value of the electrophysical quantity appearing at the input terminal of the self-function circuit and the value of the electrophysical quantity appearing at the input terminal of the mutual function circuit. Circuit module temperature calculation method characterized by the above.

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