JP2019135887A - Abnormality detection device of on-vehicle power supply device and on-vehicle power supply device - Google Patents

Abstract

To provide technology for setting an allowable range corresponding to an actual operation situation of an on-vehicle power supply device and determining abnormality on the basis of the allowable range.SOLUTION: In an on-vehicle abnormality detection device 10, an allowable range setting section 12B sets an allowable range on the basis of at least one of detection voltage, detection current and a detection temperature. A determination section 12C determines abnormality on the basis of input power inputted to a voltage conversion section 6 through an input side conducting path, output power outputted from a voltage conversion section 6 through an output side conducting path, and the allowable range which is set by the allowable range setting section 12B.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an abnormality detection device for a vehicle-mounted power supply device and a vehicle-mounted power supply device.

  Patent Document 1 discloses a failure detection method for a DCDC converter. The failure detection method disclosed in Patent Document 1 calculates input power from the product of input current and input voltage to the DCDC converter, calculates output power from the product of output current and output voltage from the DCDC converter, and inputs power. And a difference or ratio between the output power and the sum of the estimated losses is calculated, and a failure is determined based on a difference between the difference or ratio and a predetermined threshold.

Japanese Patent No. 5058024

  In the determination method of Patent Document 1, a failure determination is performed by comparing the difference or ratio between the input power and the sum of the output power and the estimated loss with a predetermined threshold. When determining the failure, the estimated loss is calculated with reference to the internal loss map based on the input voltage, the output voltage, and the output current. However, the estimated loss can fluctuate due to various factors such as manufacturing variation of components, component temperature, unit temperature, detection error, etc. The degree of variation in estimated loss depends on the voltage, current status, temperature status, etc. Can vary greatly. For this reason, when a failure is determined by comparing the difference or ratio with a threshold value as in Patent Document 1, the threshold value is set without considering the variation in estimated loss.

  The present invention has been made to solve at least one of the above-described problems, and can set an allowable range according to an actual operation state of the in-vehicle power supply device, and can perform abnormality determination based on the allowable range. The purpose is to provide technology.

The abnormality detection device for the in-vehicle power supply device according to the first invention is:
A switching element that performs an on / off operation in response to a control signal that is alternately switched between an on signal and an off signal is provided, and the voltage applied to the input side conductive path is boosted or lowered by the on / off operation of the switching element and output. A voltage converter that outputs to the side conductive path;
A voltage detection unit including an input voltage detection unit that detects an input voltage applied to the input side conductive path; and an output voltage detection unit that detects an output voltage applied to the output side conductive path;
A current detection unit including an input current detection unit that detects an input current flowing through the input side conductive path; and an output current detection unit that detects an output current flowing through the output side conductive path;
A calculation unit that repeats a feedback calculation that calculates the duty of the control signal so that the voltage of the output-side conductive path approaches a target voltage value based on at least the output voltage detected by the output voltage detection unit;
A drive unit that outputs the control signal of the duty calculated by the calculation unit to the switching element;
An abnormality detection device for detecting an abnormality of a vehicle-mounted power supply device comprising:
An allowable range setting unit for setting an allowable range used for abnormality determination;
The input power input to the voltage conversion unit via the input side conductive path, the output power output from the voltage conversion unit via the output side conductive path, and the allowable range setting unit A determination unit for determining an abnormality based on an allowable range;
Have
The allowable range setting unit sets the allowable range based on at least one of a voltage detected by the voltage detection unit or a current detected by the current detection unit.

The abnormality detection device for the in-vehicle power supply device according to the second invention is:
A switching element that performs an on / off operation in response to a control signal that is alternately switched between an on signal and an off signal is provided, and the voltage applied to the input side conductive path is boosted or lowered by the on / off operation of the switching element and output. A voltage converter that outputs to the side conductive path;
A voltage detection unit including an input voltage detection unit that detects an input voltage applied to the input side conductive path; and an output voltage detection unit that detects an output voltage applied to the output side conductive path;
A current detection unit including an input current detection unit that detects an input current flowing through the input side conductive path; and an output current detection unit that detects an output current flowing through the output side conductive path;
A temperature detector for detecting the temperature at a predetermined position in the vehicle;
A calculation unit that repeats a feedback calculation that calculates the duty of the control signal so that the voltage of the output-side conductive path approaches a target voltage value based on at least the output voltage detected by the output voltage detection unit;
A drive unit that outputs the control signal of the duty calculated by the calculation unit to the switching element;
An abnormality detection device for detecting an abnormality of a vehicle-mounted power supply device comprising:
An allowable range setting unit for setting an allowable range used for abnormality determination;
The input power input to the voltage conversion unit via the input side conductive path, the output power output from the voltage conversion unit via the output side conductive path, and the allowable range setting unit A determination unit for determining an abnormality based on an allowable range;
Have
The allowable range setting unit sets the allowable range based on at least the temperature detected by the temperature detection unit.

  The on-vehicle power supply device that is the third invention is the abnormality detection device of the first invention or the second invention, a voltage conversion unit, an input voltage detection unit, an output voltage detection unit, an input current detection unit, An output current detection unit, a calculation unit, and a drive unit are provided.

  In the first invention, the allowable range setting unit sets the allowable range based on at least one of the voltage detected by the voltage detection unit or the current detected by the current detection unit. In this way, the “allowable range” used in the abnormality determination can be changed in accordance with the input state or output state of the voltage converter, and the actual operating state (especially the actual voltage state or current) can be changed. It is easy to set an appropriate allowable range according to the state.

  In the second invention, the allowable range setting unit sets the allowable range based on the temperature detected by the temperature detection unit. In this way, the “allowable range” used in the abnormality determination can be changed according to the temperature at a predetermined position in the vehicle, and according to the actual operation situation (particularly the actual temperature situation). It becomes easier to set an appropriate tolerance.

  According to the third invention, it is possible to realize an in-vehicle power supply device that exhibits the same effect as the first invention or the second invention.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a circuit diagram schematically illustrating a vehicle-mounted power supply system including a vehicle-mounted abnormality detection device and a vehicle-mounted power supply device according to a first embodiment. 3 is a timing chart illustrating an execution mode, an abnormality determination state, a loss difference, and a determination result change in the in-vehicle power supply device according to the first embodiment. FIG. 3 is an explanatory diagram illustrating a part of setting data for a step-down mode used in an allowable range setting unit in the first embodiment, (A) is setting data when an input voltage is Va1, and (B) is input data. This is setting data when the voltage is Va2. 6 is an explanatory diagram conceptually illustrating step-down mode setting data used in an allowable range setting unit in Embodiment 1. FIG. FIG. 3 is an explanatory diagram illustrating a part of setting data for a boost mode used in an allowable range setting unit in the first embodiment, (A) is setting data when an input voltage is Vb1, and (B) is input data. This is setting data when the voltage is Vb2. 3 is an explanatory diagram conceptually illustrating boost mode setting data used in an allowable range setting unit in Embodiment 1. FIG. FIG. 6 is an explanatory diagram illustrating a part of setting data for a step-down mode used in an allowable range setting unit in the second embodiment, (A) is setting data when a detection duty is Da1, and (B) is detection. This is setting data when the duty is Da2. FIG. 12 is an explanatory diagram conceptually illustrating step-down mode setting data used in an allowable range setting unit in the second embodiment. FIG. 6 is an explanatory diagram illustrating a part of setting data for a boost mode used in an allowable range setting unit in the second embodiment, (A) is setting data when a detection duty is Db1, and (B) is a detection data. This is setting data when the duty is Db2. FIG. 9 is an explanatory diagram conceptually illustrating boost mode setting data used in an allowable range setting unit in the second embodiment. It is explanatory drawing which illustrates a part of setting data used by the tolerance | permissible_range setting part in another Example, (A) is setting data in case input voltage is Va1, (B) is input voltage Va2. It is the setting data at the time. It is explanatory drawing which illustrates notionally the setting data used by the tolerance | permissible_range setting part in another Example. It is explanatory drawing which illustrates a part of setting data used by the tolerance | permissible_range setting part in another example of another Example, (A) is setting data when a detection duty is Da1, (B) is detection This is setting data when the duty is Da2. It is explanatory drawing which illustrates notionally the setting data used by the tolerance | permissible_range setting part in another example of another Example.

The desirable form of invention is illustrated below.
In the second invention, the allowable range setting unit may set the allowable range so that the difference between the upper limit threshold and the lower limit threshold increases as the temperature detected by the temperature detection unit increases.
Since the power supply device tends to vary in loss as the temperature increases, therefore, if the allowable range is set so as to increase the difference between the upper threshold and the lower threshold as the temperature detected by the temperature detector increases, variation in loss It becomes easy to set the allowable range with the size according to the tendency.

The temperature detection part may be comprised by the temperature sensor mounted in the board | substrate with which the components which comprise a voltage conversion part are mounted.
If it does in this way, the temperature of any part which constitutes a voltage conversion part can be detected with a temperature sensor by temperature sensor, and an allowable range can be set up according to the temperature of a voltage conversion part.

  The determination unit is abnormal when the difference between the input power input via the input-side conductive path and the output power output via the output-side conductive path is outside the allowable range set by the allowable range setting unit. judge. In this way, it can be determined that there is an abnormality when a situation occurs in which the loss caused by the voltage conversion operation falls outside the allowable range.

The allowable range setting unit may set the allowable range so that the difference between the upper limit threshold and the lower limit threshold decreases as the output current detected by the output current detection unit increases.
Since the power supply device has a greater influence when an abnormality occurs as the output current is larger, the allowable range is set so as to reduce the difference between the upper threshold and the lower threshold as the output current detected by the output current detector increases. If set, priority can be given to increasing the degree of tolerance when the output current is relatively small, and protection can be given priority when the output current is relatively large.

The allowable range setting unit may set the allowable range so that the difference between the upper limit threshold and the lower limit threshold increases as the input voltage detected by the input voltage detection unit increases.
Since the loss tends to vary as the input voltage increases, the power supply device loses if the allowable range is set so that the difference between the allowable upper limit threshold and the lower limit threshold increases as the input voltage detected by the input voltage detector increases. It is easy to set an allowable range with a size that matches the tendency of variation.

<Example 1>
Embodiment 1 of the present invention will be described below.
The in-vehicle power supply device 1 (hereinafter also referred to as the power supply device 1) shown in FIG. 1 is configured as, for example, an in-vehicle step-up / step-down DCDC converter, and one of the first conductive path 91 and the second conductive path 92 is conductive. The DC voltage applied to the path is boosted or lowered and output to the other conductive path.

  The power supply device 1 includes a first conductive path 91 and a second conductive path 92 as power lines. The first conductive path 91 is a wiring that is electrically connected to a high-potential side terminal of the first power supply unit 101 that is a high-voltage power supply unit, and is electrically connected to the high-potential side terminal. The direct current voltage is applied. The second conductive path 92 is a wiring that is electrically connected to the high-potential side terminal of the second power supply unit 102 that is a low-voltage power supply unit, and is electrically connected to the high-potential side terminal. The direct current voltage is applied.

  The 1st power supply part 101 and the 2nd power supply part 102 are comprised by well-known means, such as a lead storage battery, a lithium ion battery, an electric double layer capacitor, a lithium ion capacitor, another electrical storage part, a generator, for example. The output voltage of the first power supply unit 101 may be higher than the output voltage of the second power supply unit 102, and the specific value of each output voltage is not particularly limited. The terminals on the low potential side of the first power supply unit 101 and the second power supply unit 102 are electrically connected to a ground unit (not shown) and are kept at a predetermined ground potential (0 V).

  A vehicle-mounted load 111 is electrically connected to the first conductive path 91 electrically connected to the first power supply unit 101, and the vehicle-mounted load 111 is configured to receive power supply from the first power supply unit 101. The in-vehicle load 112 is electrically connected to the second conductive path 92 electrically connected to the second power supply unit 102, and the in-vehicle load 112 is configured to receive power supply from the second power supply unit 102. The in-vehicle loads 111 and 112 are known in-vehicle electric components, and the type is not particularly limited.

  The voltage converter 6 has a function of boosting or stepping down the voltage input by the on / off operation of the switching elements S1, S2, S3, and S4 and outputting the boosted voltage. The voltage conversion unit 6 is provided between the first conductive path 91 and the second conductive path 92 and has a step-down function for performing a step-down operation and a step-up function for performing a step-up operation. In the following description, the voltage converter 6 steps down the voltage applied to the first conductive path 91 and outputs it to the second conductive path 92, and boosts the voltage applied to the second conductive path 92. An example in which the boosting function output to the first conductive path 91 can be executed will be described.

  The voltage conversion unit 6 includes switching elements S1, S2, S3, and S4 arranged in an H-bridge structure and an inductor L, and functions as a so-called bidirectional DCDC converter. The switching elements S1, S2, S3, and S4 are all configured as MOSFETs. The inductor L is configured as a known coil. In the first conductive path 91, one electrode of the capacitor 81 is electrically provided, and the other electrode of the capacitor 81 is electrically connected to the ground. One electrode of the capacitor 82 is electrically connected to the second conductive path 92, and the other electrode of the capacitor 82 is electrically connected to the ground.

  In the voltage conversion unit 6, the first conductive path 91 is electrically connected to the drain of the switching element S1, and the drain of the switching element S2 and one end of the inductor L are electrically connected to the source of the switching element S1. ing. The second conductive path 92 is electrically connected to the drain of the switching element S3, and the drain of the switching element S4 and the other end of the inductor L are electrically connected to the source of the switching element S3. The sources of the switching elements S2 and S4 are electrically connected to the ground. Each signal from the drive unit 8 described later is input to each gate of the switching elements S1, S2, S3, and S4.

  The voltage detection unit 20 includes voltage detection units 21 and 22. The voltage detection units 21 and 22 are both configured as known voltage detection circuits. The voltage detection unit 21 detects a value indicating the voltage of the first conductive path 91 (for example, a voltage value of the first conductive path 91 or a value obtained by dividing the voltage value of the first conductive path 91 by a voltage dividing circuit). To the control unit 12. The voltage detection unit 22 detects a value indicating the voltage of the second conductive path 92 (for example, a voltage value of the second conductive path 92 or a value obtained by dividing the voltage value of the second conductive path 92 by a voltage dividing circuit). To the control unit 12. The control unit 12 can specify the voltage value of the first conductive path 91 based on the value input from the voltage detection unit 21 (the detection value of the voltage detection unit 21), and the value input from the voltage detection unit 22 The voltage value of the second conductive path 92 can be specified based on (the detection value of the voltage detection unit 21).

  The current detection unit 30 includes current detection units 31 and 32. The current detection units 31 and 32 are both configured as a known current detection circuit. The current detection unit 31 is a current detection circuit that detects a current flowing through the first conductive path 91. For example, a differential circuit that amplifies and outputs a shunt resistor provided in the first conductive path 91 and a voltage across the shunt resistor. And an amplifier. The current detection unit 32 is a current detection circuit that detects a current flowing through the second conductive path 92. For example, a differential circuit that amplifies and outputs a shunt resistor provided in the second conductive path 92 and a voltage across the shunt resistor. And an amplifier. The control unit 12 specifies the value of the current flowing through the first conductive path 91 based on the value input from the current detection unit 31 (the detection value of the current detection unit 31), and the value input from the current detection unit 32 ( The value of the current flowing through the second conductive path 92 is specified based on the detection value of the current detector 32.

  The temperature detection unit 40 is configured by a known temperature sensor such as a thermistor, and is configured to detect the temperature at a predetermined position in the vehicle on which the power supply device 1 is mounted. The temperature detection unit 40 is mounted on a substrate on which components (switching elements S1, S2, S3, S4, inductor L, etc.) constituting the voltage conversion unit 6 are mounted, and the position where the temperature detection unit 40 is mounted on the substrate. The voltage signal which shows the temperature of this is output. The voltage signal generated by the temperature detection unit 40 is input to the control unit 12, and the control unit 12 can grasp the temperature detected by the temperature detection unit 40.

  The control unit 12 is configured as a microcomputer, for example, and performs feedback control by a known method based on the voltage value and the current value input from the voltage detection unit 20 and the current detection unit 30 and the target voltage value, thereby converting the voltage. The duty of the PWM signal given to the unit 6 is set. Then, the PWM signal having the set duty is output to the drive unit 8. The target voltage value may be a value set by the control unit 12 or a value instructed from an external device such as an external ECU.

  The drive unit 8 is a circuit that outputs a control signal for turning on and off the switching elements S1, S2, S3, and S4. The drive unit 8 has a function of outputting a PWM signal having a duty set by the control unit 12 to the voltage conversion unit 6.

  In the step-down mode, synchronous rectification control is performed by the operations of the control unit 12 and the drive unit 8 so that PWM signals are complementarily output in a form in which dead times are set for the gates of the switching elements S1 and S2. Specifically, during the output of an ON signal (for example, H level signal) to the switching element S1, an OFF signal (for example, L level signal) is output to the switching element S2, and an ON signal (for example, H level) to the switching element S2. During the output of the signal), synchronous rectification control is performed so that an off signal (for example, an L level signal) is output to the switching element S1. By this control, the DC voltage (input voltage) applied to the first conductive path 91 is lowered, and the second conductive path 92 has an output voltage lower than the input voltage applied to the first conductive path 91. Is applied. The output voltage applied to the second conductive path 92 is determined according to the duty of the PWM signal applied to the gate of the switching element S1. In the step-down mode, the ON signal is continuously input to the gate of the switching element S3, and the switching element S3 is maintained in the ON state. Further, the OFF signal is continuously input to the gate of the switching element S4, and the switching element S4 is maintained in the OFF state.

  In the step-down mode, the control unit 12 performs feedback control in a known manner. Specifically, the calculation unit 12A, which forms a part of the control unit 12, has the second conductive path 92 (in step-down mode) based on the output voltage detected by the voltage detection unit 22 (output voltage detection unit in step-down mode). The feedback calculation for calculating the duty of the PWM signal (control signal) is periodically repeated so that the voltage of the output side conductive path) approaches the target voltage value. In the feedback calculation periodically executed, a known feedback calculation process such as PID calculation or PI calculation is performed based on the deviation between the output voltage value and the target voltage value, and a new value for bringing the output voltage value closer to the target voltage value is obtained. The correct duty. The control unit 12 continuously outputs the PWM signal (control signal) during the step-down mode, and the duty of the PWM signal (control signal) is newly obtained by the feedback calculation every time the calculation unit 12A performs the feedback calculation. Change to duty. The drive unit 8 acquires the PWM signal given from the control unit 12, and outputs a PWM signal having the same period and the same duty as the PWM signal to the gate of the switching element S1. The PWM signal output from the drive unit 8 to the gate of the switching element S1 is adjusted to an appropriate level at which the voltage of the ON signal (H level signal) can turn on the switching element S1. Then, the drive unit 8 outputs a PWM signal complementary to the PWM signal output to the gate of the switching element S1 to the gate of the switching element S2, and performs synchronous rectification control.

  In the step-down mode, the first conductive path 91 corresponds to an example of an input side conductive path, and the second conductive path 92 corresponds to an example of an output side conductive path. Furthermore, the voltage detector 21 corresponds to an example of an input voltage detector, and the voltage detector 22 corresponds to an example of an output voltage detector. The current detection unit 32 corresponds to an example of an output current detection unit, and the current detection unit 31 corresponds to an example of an input current detection unit.

  In the boost mode, synchronous rectification control is performed by the operations of the control unit 12 and the drive unit 8 so that the PWM signal is complementarily output in a form in which a dead time is set for each gate of the switching elements S1 and S2. Specifically, during the output of an ON signal (for example, an H level signal) to the switching element S2, an OFF signal (for example, an L level signal) is output to the switching element S1, and an ON signal (for example, an H level) to the switching element S1. During the output of the signal), synchronous rectification control is performed so that an off signal (for example, an L level signal) is output to the switching element S2. By this control, the DC voltage (input voltage) applied to the second conductive path 92 is boosted, and the first conductive path 91 has an output voltage higher than the input voltage applied to the second conductive path 92. Is applied. The output voltage applied to the first conductive path 91 is determined according to the duty of the PWM signal applied to the gate of the switching element S2. In the boost mode, the ON signal is continuously input to the gate of the switching element S3, and the switching element S3 is maintained in the ON state. Further, the OFF signal is continuously input to the gate of the switching element S4, and the switching element S4 is maintained in the OFF state.

  In the step-up mode, the control unit 12 performs feedback control in a known manner. Specifically, the calculation unit 12A, which forms a part of the control unit 12, has the first conductive path 91 (in the boost mode) based on the output voltage detected by the voltage detection unit 21 (the output voltage detection unit in the boost mode). The feedback calculation for calculating the duty of the PWM signal (control signal) is periodically repeated so that the voltage of the output side conductive path) approaches the target voltage value. The feedback calculation can be performed similarly to the step-down mode. The control unit 12 continuously outputs a PWM signal (control signal) during the boost mode, and the duty of the PWM signal (control signal) is newly obtained by the feedback calculation every time the calculation unit 12A performs the feedback calculation. Change to duty. The drive unit 8 acquires the PWM signal given from the control unit 12, and outputs a PWM signal having the same period and the same duty as the PWM signal to the gate of the switching element S2. The PWM signal output from the drive unit 8 to the gate of the switching element S2 is adjusted to an appropriate level at which the voltage of the ON signal (H level signal) can turn on the switching element S2. And the drive part 8 outputs a PWM signal complementary to the PWM signal output to the gate of the switching element S2 to the gate of the switching element S1, and performs synchronous rectification control.

  In the boost mode, the second conductive path 92 corresponds to an example of an input side conductive path, and the first conductive path 91 corresponds to an example of an output side conductive path. Furthermore, the voltage detector 22 corresponds to an example of an input voltage detector, and the voltage detector 21 corresponds to an example of an output voltage detector. The current detection unit 31 corresponds to an example of an output current detection unit, and the current detection unit 32 corresponds to an example of an input current detection unit.

  Here, the abnormality determination process executed during the operation of the power supply device 1 will be described with reference to the timing chart of FIG.

  The control unit 12 forming a part of the power supply device 1 switches to the operation mode when a predetermined start condition is satisfied, and switches to the stop mode when a predetermined end condition is satisfied. The operation mode mainly includes an initialization mode, a standby mode, a step-down mode, a step-up mode, a sleep mode, and the like. In the timing chart of FIG. 2, the execution timing of each mode during the operation mode, the timing of processing relating to abnormality detection, the loss difference, the abnormality determination result, and the like are shown over time.

  The predetermined start condition is, for example, that a start switch (for example, an ignition switch) for starting the vehicle is switched from an off state to an on state, and the predetermined end condition is, for example, that the start switch (such as an ignition switch) is on It is to switch to the off state. Specifically, the control unit 12 switches from the stop mode to the initialization mode when the start switch of the vehicle is switched from the off state to the on state, and after a predetermined initialization process is performed in the initialization mode, Switch to standby mode. In the example of FIG. 2, the control unit 12 switches to the standby mode at time t1, and performs a predetermined offset diagnosis in the standby mode.

  The control unit 12 switches to the step-down mode when a predetermined step-down operation start condition is satisfied, and executes the operation in the step-down mode. In the example of FIG. 2, a predetermined step-down operation start condition is established at time t3 in the standby mode, and the control unit 12 performs step-down mode between time t3 and time t4 according to the establishment of the step-down operation start condition. Is doing the operation. Further, after the standby mode set from time t7 to time t8, the step-down operation start condition is satisfied at time t8, and the control unit 12 operates in the step-down mode even after time t8. When the control unit 12 switches to the step-down mode, the control unit 12 steps down the DC voltage (input voltage) applied to the first conductive path 91 and applies a voltage to the second conductive path 92 so as to apply an output voltage lower than the input voltage. The converter 6 is caused to perform a step-down operation.

  The permissible range setting unit 12B that forms part of the control unit 12 sets a permissible range used for abnormality determination while the step-down mode operation is performed in this way. Then, the determination unit 12C includes the input power Pa input to the voltage conversion unit 9 via the first conductive path 91 (the input side conductive path in the step-down mode) and the voltage conversion unit 6 during the operation in the step-down mode. Is determined based on the output power Pb output through the second conductive path 92 (output-side conductive path in the step-down mode) and the allowable range set by the allowable range setting unit 12B.

  Here, a setting method of the allowable range will be exemplified. The allowable range setting unit 12B is based on the voltage detected by the voltage detection unit 20, the current detected by the current detection unit 30, and the temperature detected by the temperature detection unit 40 during operation in the step-down mode. To set the allowable range. In this configuration, the temperature detected by the temperature detection unit 40, the output current detected by the current detection unit 32 (output current detection unit in step-down mode), and the voltage detection unit 21 (input voltage detection unit in step-down mode) Step-down setting data (table data as shown in FIG. 4) for determining the allowable range based on the input voltage detected by (1) is prepared, and the allowable range setting unit 12B sets the allowable range according to the setting data. .

  Here, a case where table data as shown in FIG. 4 is used as setting data is illustrated. 3 and 4 conceptually show an example of table data. As the setting data used in the allowable range setting unit 12B, for example, as shown in FIGS. 3A and 3B, data for determining an allowable range is prepared for each input voltage. FIG. The table data exemplifies table data that defines an allowable range based on the output current and the detected temperature when the input voltage is Va1. FIG. 3B illustrates table data that defines an allowable range based on the output current and the detected temperature when the input voltage is Va2.

  FIG. 3A shows table data when the input voltage is Va1. When this table data is used, for example, if the output current is Ib1 and the temperature is T3, the allowable range determined by the data of A113. Is used. Data such as A111, A112, and A113 (data that defines an allowable range) all define an upper limit threshold and a lower limit threshold for a difference (Pa−Pb) between the input power Pa and the output power Pb. When the allowable range is defined by the data, it is determined that the loss is out of the allowable range when the loss difference (Pa−Pb), which is the difference between the input power Pa and the output power Pb, exceeds the upper limit threshold of the data of A113. Even when the loss difference (Pa−Pb) is lower than the lower limit threshold of the data A113, it is determined that the loss is outside the allowable range.

  In the setting data (FIG. 4) used in the allowable range setting unit 12B, table data as shown in FIGS. 3A and 3B is prepared for each input voltage value, and a plurality of table data as shown in FIG. It is a set of.

  In the setting data (FIG. 4) used in the allowable range setting unit 12B, the allowable range is determined so that the allowable range increases as the temperature T detected by the temperature detection unit 40 increases. The current detection unit 32 (step-down mode) The allowable range is determined such that the allowable range is reduced as the output current Ib detected by the output current detection unit in (2) increases, and the input detected by the voltage detection unit 21 (input voltage detection unit in the step-down mode). The allowable range is determined such that the allowable range is increased as the voltage Va increases.

  More specifically, the step-down setting data shown in FIG. 4 is data in which the upper limit threshold of the allowable range increases and the lower limit threshold of the allowable range decreases as the temperature T detected by the temperature detection unit 40 increases. It has a configuration. This setting data is, for example, as the temperature T detected by the temperature detection unit 40 increases, regardless of the combination of the input voltage Va and the output current Ib in the predetermined input voltage range and the predetermined output current range. The data sets the allowable range so that the upper limit threshold of the allowable range is increased and the lower limit threshold of the allowable range is decreased. Further, the setting data is stored in the current detection unit 32 (in step-down mode) regardless of the combination of the temperature T detected by the temperature detection unit 40 and the input voltage Va in a predetermined temperature range and the input voltage range. The upper limit threshold value of the allowable range decreases as the output current Ib detected by the output current detection unit) increases, and the allowable range is set such that the lower limit threshold value of the allowable range increases. Further, the setting data includes the upper limit of the allowable range as the input voltage Va increases regardless of the combination of the temperature T and the output current Ib detected by the temperature detection unit 40 in the temperature range and the output current range. The data sets the allowable range so that the threshold value increases and the lower limit threshold value of the allowable range decreases.

  When the abnormality determination is performed during the operation in the step-down mode, the allowable range setting unit 12B applies to the first conductive path 91 (the input side conductive path in the step-down mode) during the operation in the step-down mode (voltage conversion). Information indicating the input voltage Va, the output current Ib flowing through the second conductive path 92 (the output-side conductive path in the step-down mode), and the temperature T at the position of the temperature detection unit 40, the voltage detection unit 21 and the current Obtained from the detection unit 32 and the temperature detection unit 40, respectively. Then, an allowable range corresponding to the detected input voltage Va, output current Ib, and temperature T is selected from the step-down setting data (FIG. 4). When there is no data corresponding to any of the input voltage Va, the output current Ib, and the temperature T, the closest data may be used or a known interpolation process may be used. For example, in the step-down setting data (FIG. 4), when there is no data corresponding to the detected input voltage Va, it is detected from the input voltage candidates included in the step-down setting data (FIG. 4). A value closest to the input voltage Va may be selected. The permissible range setting unit 12B may perform such permissible range setting processing only once during the step-down mode, and may continue to use the obtained permissible range during the step-down mode. It may be repeated during the mode, and the allowable range used (the allowable range used for the determination unit 12C) may be updated each time a new allowable range is obtained.

  The determination unit 12C outputs the input power Pa input via the first conductive path 91 (input side conductive path in the step-down mode) and the second conductive path 92 (output side conductive path in the step-down mode). The loss difference calculation process for calculating the loss difference (Pa−Pb) that is the difference from the output power Pb is continuously repeated. Specifically, the determination unit 12C obtains the input power Pa from the equation Pa = Va × Ia based on the input voltage Va detected by the voltage detection unit 21 and the input current Ia detected by the current detection unit 31. Based on the output voltage Vb detected by the voltage detection unit 22 and the output current Ib detected by the current detection unit 32, the output power Pb is obtained by the expression Pb = Vb × Ib, and these input power Pa and output power Pb Loss difference calculation processing is performed so as to calculate a loss difference (Pa−Pb) that is a difference between the two. Such loss difference calculation processing is repeatedly performed during the step-down mode, and the loss difference (Pa−Pb) obtained by any loss difference calculation processing is outside the allowable range set by the allowable range setting unit 12B. Is determined to be abnormal.

  For example, the input voltage Va detected by the voltage detection unit 21 during the step-down mode is Va2, the output current Ib detected by the current detection unit 32 is Ib4, and the temperature T detected by the temperature detection unit 40 is T4. In this case, the allowable range setting unit 12B specifies the allowable range based on the data A244 corresponding to the input voltage Va2, the output current Ib4, and the detected temperature T4 based on the table data as shown in FIG. The determination unit 12C continuously repeats the loss difference calculation process for calculating the loss difference (Pa−Pb) by the above-described method, and a situation has occurred in which the loss difference (Pa−Pb) exceeds the upper limit threshold determined by the data A244. In the case, it is determined as abnormal. The determination unit 12C also determines that an abnormality has occurred when a situation occurs in which the loss difference (Pa−Pb) is lower than the lower limit threshold defined by the data A244. On the other hand, the determination unit 12C maintains the loss difference (Pa−Pb) at or below the upper threshold defined by the data A244 and above the lower threshold during the step-down mode (from the start of the step-down mode to switching to another mode). In this case, it is not determined as abnormal in the step-down mode. In the example of FIG. 2, the loss difference exceeds the upper limit threshold after time t9 in the step-down mode after time t8, and when such a situation occurs, the determination unit 12C determines that there is an abnormality. In FIG. 2, the loss difference, the upper threshold value, and the lower threshold value are simply shown. However, in actuality, the loss difference changes every time the loss difference is detected, and the upper threshold value and the lower threshold value are allowable. It changes each time a range is set.

Next, the operation in the boost mode will be described.
The control unit 12 switches to the boost mode when a predetermined boost operation start condition is satisfied, and executes the boost mode operation. In the example of FIG. 2, a predetermined boost operation start condition is satisfied at time t4 in the standby mode, and the control unit 12 performs the boost mode between time t4 and time t5 according to the satisfaction of the boost operation start condition. Is doing the operation. When the control unit 12 switches to the boost mode, the control unit 12 boosts the DC voltage (input voltage) applied to the second conductive path 92 and applies a voltage to the first conductive path 91 so that an output voltage lower than the input voltage is applied. The converter 6 is caused to perform a boosting operation.

  The permissible range setting unit 12B that forms part of the control unit 12 sets a permissible range used for abnormality determination while the boost mode operation is performed in this way. Then, the determination unit 12C includes the input power Pb input to the voltage conversion unit 9 via the second conductive path 92 (the input side conductive path in the boost mode) and the voltage conversion unit 6 during the operation in the boost mode. Is determined based on the output power Pa output via the first conductive path 91 (output-side conductive path in the boost mode) and the allowable range set by the allowable range setting unit 12B.

  The setting method of the allowable range in the step-up mode is the same as that in the step-down mode. The allowable range setting unit 12B is based on the voltage detected by the voltage detection unit 20, the current detected by the current detection unit 30, and the temperature detected by the temperature detection unit 40 during operation in the boost mode. To set the allowable range. In this configuration, the temperature detected by the temperature detector 40, the output current detected by the current detector 31 (output current detector in boost mode), and the voltage detector 22 (input voltage detector in boost mode). The step-up setting data for determining the allowable range is prepared based on the input voltage detected by (1), and the allowable range setting unit 12B sets the allowable range according to the setting data. The step-up setting data is the same as the step-down setting data. For example, as shown in FIGS. 5A and 5B, data for determining an allowable range is prepared for each input voltage. In FIG. 5A, the output current is obtained when the input voltage is Vb1. Table data defining an allowable range based on the detected temperature and the detected temperature is illustrated. FIG. 5B illustrates table data that defines an allowable range based on the output current and the detected temperature when the input voltage is Vb2.

  FIG. 5A shows table data when the input voltage is Vb1. When this table data is used, for example, if the output current is Ia1 and the temperature is T3, the allowable range defined by the data of B113. Is used. Data such as B111, B112, and B113 (data that defines an allowable range) all define an upper limit threshold and a lower limit threshold of the difference (Pb−Pa) between the input power Pb and the output power Pa. When the allowable range is determined by the data, it is determined that the loss is out of the allowable range when the loss difference (Pb−Pa) that is the difference between the input power Pb and the output power Pa exceeds the upper limit threshold of the data of B113. Even when the loss difference (Pb−Pa) is lower than the lower limit threshold value of the data B113, it is determined that the loss is outside the allowable range. In the setting data (FIG. 6) used in the allowable range setting unit 12B, table data as shown in FIGS. 5A and 5B is prepared for each value of the input voltage, and a plurality of table data as shown in FIG. It is a set of.

  Also in this example, the setting data (FIG. 6) used in the allowable range setting unit 12B sets the allowable range so that the allowable range increases as the temperature T detected by the temperature detection unit 40 increases. The allowable range is determined such that the allowable range decreases as the output current Ia detected by the output current detection unit 31 (the output current detection unit in the boost mode) increases. The voltage detection unit 22 (the input voltage detection unit in the boost mode) The allowable range is determined such that the allowable range increases as the detected input voltage Vb increases.

  More specifically, the setting data for boosting shown in FIG. 6 is data in which the upper limit threshold of the allowable range increases and the lower limit threshold of the allowable range decreases as the temperature T detected by the temperature detection unit 40 increases. It has a configuration. This setting data is, for example, as the temperature T detected by the temperature detection unit 40 increases, regardless of the combination of the input voltage Vb and the output current Ia in the predetermined input voltage range and the predetermined output current range. The data sets the allowable range so that the upper limit threshold of the allowable range is increased and the lower limit threshold of the allowable range is decreased. Further, the setting data is stored in the current detection unit 31 (in boost mode) regardless of the combination of the temperature T detected by the temperature detection unit 40 and the input voltage Vb in the predetermined temperature range and the input voltage range. The upper limit threshold value of the allowable range decreases as the output current Ia detected by the output current detection unit) increases, and the allowable range is set such that the lower limit threshold value of the allowable range increases. Further, the setting data includes an upper limit of the allowable range as the input voltage Vb increases regardless of the combination of the temperature T and the output current Ia detected by the temperature detection unit 40 in the temperature range and the output current range. The data sets the allowable range so that the threshold value increases and the lower limit threshold value of the allowable range decreases.

  When the abnormality determination is performed during the operation in the boost mode, the allowable range setting unit 12B applies to the second conductive path 92 (the input side conductive path in the boost mode) during the operation in the boost mode (voltage conversion). Information indicating the input voltage Vb, the output current Ia flowing through the first conductive path 91 (the output-side conductive path in the boost mode), and the temperature T at the position of the temperature detection unit 40, the voltage detection unit 22, the current Obtained from the detection unit 31 and the temperature detection unit 40, respectively. Then, an allowable range corresponding to the detected input voltage Vb, output current Ia, and temperature T is selected from the setting data for boosting (FIG. 6). When there is no data corresponding to any of the input voltage Vb, the output current Ia, and the temperature T, the closest data may be used or a known interpolation process may be used. The permissible range setting unit 12B may perform such a permissible range setting process only once during the boost mode, and may continue to use the obtained permissible range during the boost mode. It may be repeated during the mode, and the allowable range used (the allowable range used for the determination unit 12C) may be updated each time a new allowable range is obtained.

  The determination unit 12C outputs the input power Pb input via the second conductive path 92 (input side conductive path in the boost mode) and the first conductive path 91 (output side conductive path in the boost mode). The loss difference calculation process for calculating the loss difference (Pb−Pa) that is the difference from the output power Pa is continuously repeated. Specifically, the determination unit 12C obtains the input power Pb from the input voltage Vb detected by the voltage detection unit 22 and the input current Ib detected by the current detection unit 32 by the equation Pb = Vb × Ib. Based on the output voltage Va detected by the voltage detector 21 and the output current Ia detected by the current detector 31, the output power Pa is obtained by the equation Pa = Va × Ia, and the input power Pb and the output power Pa Loss difference calculation processing is performed so as to calculate a loss difference (Pb−Pa) that is a difference between the two. Such loss difference calculation processing is repeatedly performed during the boost mode, and the loss difference (Pb−Pa) obtained by any loss difference calculation processing is outside the allowable range set by the allowable range setting unit 12B. Is determined to be abnormal.

  The determination unit 12C performs a predetermined abnormality handling process when it is determined as abnormal in the above-described abnormality determination even in the step-down mode or the step-up mode. As the abnormality handling process, a predetermined notification process such as transmitting information indicating an abnormality to the host information processing apparatus may be performed, and a forced stop process for forcibly stopping the operation of the voltage conversion unit 6 May be performed.

Next, the effect of this configuration will be exemplified.
In the abnormality detection device 10 described above, the allowable range setting unit 12B sets the allowable range based on the voltage detected by the voltage detection unit 20 and the current detected by the current detection unit 30. In this way, the “allowable range” used in the abnormality determination can be changed according to the input state and output state of the voltage converter 6, and an appropriate allowable range according to the actual operation state can be set. Easy to set.

  Further, the allowable range setting unit 12B sets the allowable range based on the temperature detected by the temperature detection unit 40. In this way, the “allowable range” used in abnormality determination can be changed according to the temperature at a predetermined position in the vehicle, and it is easy to set an appropriate allowable range according to the actual temperature situation. Become.

  The allowable range setting unit 12B sets the allowable range so that the difference between the upper limit threshold and the lower limit threshold increases as the temperature T detected by the temperature detection unit 40 increases. Since the power supply device 1 tends to vary in loss as the temperature increases, if the allowable range is set so as to increase the difference between the upper threshold and the lower threshold as the temperature detected by the temperature detection unit 40 increases, variation in loss may occur. It becomes easy to set the allowable range with the size according to the tendency.

  The temperature detection unit 40 is configured by a temperature sensor mounted on a substrate on which components constituting the voltage conversion unit 6 are mounted. If it does in this way, the temperature of any part which constitutes voltage conversion part 6 can be detected with a temperature sensor, and an allowable range can be set up according to the temperature of voltage conversion part 6. .

  The determination unit 12C determines that the difference between the input power input via the input side conductive path and the output power output via the output side conductive path is outside the allowable range set by the allowable range setting unit 12B. Judge as abnormal. In this way, it can be determined that there is an abnormality when a situation occurs in which the loss caused by the voltage conversion operation falls outside the allowable range.

  The allowable range setting unit 12B sets the allowable range so that the difference between the upper limit threshold and the lower limit threshold decreases as the output current detected by the output current detection unit increases. Since the power supply device 1 has a larger influence when an abnormality occurs as the output current increases, the allowable range is set so that the difference between the upper limit threshold and the lower limit threshold decreases as the output current detected by the output current detection unit increases. If the output current is relatively small, the tolerance can be increased to give priority to continued operation, and when the output current is relatively large, protection can be given priority.

  The allowable range setting unit 12B sets the allowable range so that the difference between the upper limit threshold and the lower limit threshold increases as the input voltage detected by the input voltage detection unit increases. Since the power supply device 1 tends to vary in loss as the input voltage increases, if the allowable range is set so as to increase the difference between the upper threshold and the lower threshold as the input voltage detected by the input voltage detector increases, the loss It is easy to set an allowable range with a size that matches the tendency of variation.

<Example 2>
Next, Example 2 will be described.
The second embodiment is different from the first embodiment only in the setting method of the allowable range by the allowable range setting unit, and is the same as the first embodiment except for this point. Therefore, in the following description, parts different from the first embodiment will be mainly described. In the second embodiment, the hardware configuration is the same as that shown in FIG.

  First, the case where the vehicle-mounted power supply device 1 (FIG. 1) according to the second embodiment operates in the step-down mode will be described. Since the operation of the voltage conversion unit 6 during the step-down mode is the same as that of the first embodiment, detailed description of the operation of the voltage conversion unit 6 is omitted, and the abnormality determination during the step-down mode will be described in detail below.

  The allowable range setting unit 12B illustrated in FIG. 1 is configured such that the voltage detected by the voltage detection unit 20, the current detected by the current detection unit 30, and the temperature detected by the temperature detection unit 40 during operation in the step-down mode. Based on the above, an allowable range is set. Specifically, the temperature detected by the temperature detector 40, the output current Ib detected by the current detector 32 (output current detector in step-down mode), and the voltage detector 21 (input voltage in step-down mode). Setting data for step-down (see FIG. 8) that defines an allowable range based on the input voltage Va detected by the detection unit) and the output voltage Vb detected by the voltage detection unit 22 (output voltage detection unit in the step-down mode). Table data) is prepared, and the allowable range setting unit 12B sets the allowable range according to the setting data. As the setting data used in the allowable range setting unit 12B, for example, as shown in FIGS. 7A and 7B, data for determining the allowable range is prepared for each detection duty. FIG. The table exemplifies table data that defines an allowable range based on the output current and the detected temperature when the detection duty is Da1. FIG. 7B illustrates table data that defines an allowable range based on the output current and the detected temperature when the detection duty is Da2. The detection duty Da in the step-down mode is a value defined by Da = Vb / Va based on the input voltage Va and the output voltage Vb.

  FIG. 7A shows table data when the detection duty is Da1, and when this table data is used, for example, if the output current is Ib1 and the temperature is T3, the allowable range determined by the data of a113. Is used. All of the data (data defining the allowable range) such as a111, a112, and a113 define an upper limit threshold value and a lower limit threshold value of the difference (Pa−Pb) between the input power Pa and the output power Pb. When the allowable range is determined by the data, it is determined that the loss is out of the allowable range when the loss difference (Pa−Pb), which is the difference between the input power Pa and the output power Pb, exceeds the upper limit threshold of the data of a113. Even when the loss difference (Pa−Pb) is lower than the lower limit threshold of the data a113, it is determined that the allowable range has been exceeded.

  In the setting data (FIG. 8) used in the allowable range setting unit 12B, table data as shown in FIGS. 7A and 7B is prepared for each detection duty value, and a plurality of table data as shown in FIG. It is a set of. The setting data (FIG. 8) used in the allowable range setting unit 12B determines the allowable range so that the allowable range increases as the temperature T detected by the temperature detection unit 40 increases, and the current detection unit 32 (step-down mode) The permissible range is determined such that the permissible range is reduced as the output current Ib detected by the output current detecting unit) increases. More specifically, the step-down setting data shown in FIG. 8 is data in which the upper limit threshold of the allowable range increases and the lower limit threshold of the allowable range decreases as the temperature T detected by the temperature detection unit 40 increases. It has a configuration. For example, the setting data is more acceptable as the temperature T detected by the temperature detection unit 40 increases, regardless of the combination of the detection duty Da and the output current Ib in the predetermined duty range and the predetermined output current range. The data sets the allowable range so that the upper limit threshold of the range is increased and the lower limit threshold of the allowable range is decreased. Further, the setting data is obtained from the current detection unit 32 (output in the step-down mode) regardless of the combination of the temperature T and the duty Da detected by the temperature detection unit 40 in the predetermined temperature range and the duty range. The upper limit threshold value of the allowable range decreases as the output current Ib detected by the current detection unit) increases, and the allowable range is set so that the lower limit threshold value of the allowable range increases.

  When the abnormality determination is performed during the operation in the step-down mode, the allowable range setting unit 12B applies to the first conductive path 91 (the input side conductive path in the step-down mode) during the operation in the step-down mode (voltage conversion). Input voltage Va, output voltage Vb applied to second conductive path 92 (output-side conductive path in step-down mode), and output current flowing through second conductive path 92 (output-side conductive path in step-down mode) Information indicating Ib and the temperature T at the position of the temperature detection unit 40 is acquired from the voltage detection unit 20, the current detection unit 32, and the temperature detection unit 40, respectively. Then, an allowable range corresponding to the detection duty Da (Da = Vb / Va), the output current Ib, and the temperature T is selected from the setting data for step-down (FIG. 8). When there is no data corresponding to any of the detection duty Da, the output current Ib, and the temperature T, the closest data may be used, or a known interpolation process may be used. For example, when there is no data corresponding to the detected duty Da in the step-down setting data (FIG. 8), the value closest to the detected duty Da among the candidates for the duty included in the step-down setting data (FIG. 8). May be selected. The permissible range setting unit 12B may perform such permissible range setting processing only once during the step-down mode, and may continue to use the obtained permissible range during the step-down mode. It may be repeated during the mode, and the allowable range used (the allowable range used for the determination unit 12C) may be updated each time a new allowable range is obtained.

  The determination unit 12C outputs the input power Pa input via the first conductive path 91 (input side conductive path in the step-down mode) and the second conductive path 92 (output side conductive path in the step-down mode). The loss difference calculation process for calculating the loss difference (Pa−Pb) that is the difference from the output power Pb is continuously repeated. The calculation method of the loss difference (Pa−Pb) is the same as that in the first embodiment. Such loss difference calculation processing is repeatedly performed during the step-down mode, and the loss difference (Pa−Pb) obtained by any loss difference calculation processing is outside the allowable range set by the allowable range setting unit 12B. Is determined to be abnormal.

  For example, the duty Da obtained based on the input voltage Va and the output voltage Vb detected by the voltage detector 20 during the step-down mode is Da2, the output current Ib detected by the current detector 32 is Ib4, and the temperature When the temperature T detected by the detection unit 40 is T4, the allowable range setting unit 12B, based on the table data as shown in FIG. 7B, the data a244 corresponding to the duty Da2, the output current Ib4, and the detection temperature T4. The allowable range is specified by. The determination unit 12C continuously repeats the loss difference calculation process for calculating the loss difference (Pa−Pb) by the above-described method, and a situation has occurred in which the loss difference (Pa−Pb) exceeds the upper limit threshold determined by the data a244. In the case, it is determined as abnormal. The determination unit 12C also determines that an abnormality has occurred when a situation occurs in which the loss difference (Pa−Pb) is lower than the lower limit threshold defined by the data a244. On the other hand, the determination unit 12C maintains the loss difference (Pa−Pb) not more than the upper limit threshold defined by the data a244 and not less than the lower limit threshold during the step-down mode (from the start of the step-down mode to switching to another mode). In this case, it is not determined as abnormal in the step-down mode.

  Next, the operation in the boost mode will be described. Since the operation of the voltage converter 6 during the boost mode is the same as that of the first embodiment, detailed description of the operation of the voltage converter 6 is omitted, and the abnormality determination during the boost mode will be described in detail below.

  The allowable range setting unit 12B illustrated in FIG. 1 is configured such that the voltage detected by the voltage detection unit 20, the current detected by the current detection unit 30, and the temperature detected by the temperature detection unit 40 during operation in the boost mode. Based on the above, an allowable range is set. Specifically, the temperature detected by the temperature detector 40, the output current Ia detected by the current detector 31 (output current detector in boost mode), and the voltage detector 22 (input voltage in boost mode). The setting data for boosting (shown in FIG. 10) that defines an allowable range based on the input voltage Va detected by the detecting unit) and the output voltage Vb detected by the voltage detecting unit 21 (output voltage detecting unit in the boosting mode). Table data) is prepared, and the allowable range setting unit 12B sets the allowable range according to the setting data. As the setting data used in the allowable range setting unit 12B, for example, as shown in FIGS. 9A and 9B, data for determining the allowable range is prepared for each detection duty. The table data exemplifies table data that defines an allowable range based on the output current Ia and the detected temperature T when the detection duty Db is Db1. FIG. 9B illustrates table data that defines an allowable range based on the output current Ia and the detected temperature T when the detection duty Db is Db2. The detection duty Db in the boost mode is a value defined by Db = (1−Vb / Va) based on the input voltage Vb and the output voltage Va.

  FIG. 9A shows table data when the detection duty is Db1, and when this table data is used, for example, if the output current is Ia1 and the temperature is T3, the allowable range defined by the data of b113. Is used. Data such as b111, b112, b113 (data defining the allowable range) all define an upper limit threshold and a lower limit threshold of the difference (Pb−Pa) between the input power Pb and the output power Pa. When the allowable range is determined by the data, it is determined that the loss is out of the allowable range when the loss difference (Pb−Pa), which is the difference between the input power Pb and the output power Pa, exceeds the upper limit threshold of the data of b113. Even when the loss difference (Pb−Pa) is lower than the lower limit threshold value of b113 data, it is determined that the loss is outside the allowable range.

  In the setting data (FIG. 10) used in the allowable range setting unit 12B, table data as shown in FIGS. 9A and 9B is prepared for each detection duty value, and a plurality of table data as shown in FIG. It is a set of. In the setting data (FIG. 10) used in the allowable range setting unit 12B, the allowable range is determined such that the allowable range increases as the temperature T detected by the temperature detection unit 40 increases. The current detection unit 32 (boost mode) The permissible range is determined such that the permissible range is reduced as the output current Ia detected by the output current detecting unit) increases. More specifically, the setting data for boosting shown in FIG. 10 is data in which the upper limit threshold of the allowable range increases and the lower limit threshold of the allowable range decreases as the temperature T detected by the temperature detection unit 40 increases. It has a configuration. This setting data is, for example, acceptable as the temperature T detected by the temperature detection unit 40 increases, regardless of the combination of the detection duty Db and the output current Ia in the predetermined duty range and the predetermined output current range. The data sets the allowable range so that the upper limit threshold of the range is increased and the lower limit threshold of the allowable range is decreased. Further, the setting data is obtained from the current detection unit 32 (output in the boost mode) regardless of the combination of the temperature T and the duty Db detected by the temperature detection unit 40 in the predetermined temperature range and the duty range. The upper limit threshold value of the allowable range decreases as the output current Ia detected by the current detection unit) increases, and the allowable range is set such that the lower limit threshold value of the allowable range increases.

  When the abnormality determination is performed during the operation in the boost mode, the allowable range setting unit 12B applies to the second conductive path 92 (the input side conductive path in the boost mode) during the operation in the boost mode (voltage conversion). Input voltage Vb, output voltage Va applied to first conductive path 91 (output-side conductive path in boost mode), and output current flowing through first conductive path 91 (output-side conductive path in boost mode) Information indicating Ia and the temperature T at the position of the temperature detection unit 40 is acquired from the voltage detection unit 20, the current detection unit 31, and the temperature detection unit 40, respectively. Then, an allowable range corresponding to the detection duty Db (Db = 1−Vb / Va), the output current Ia, and the temperature T is selected from the setting data for boosting (FIG. 10). When there is no data corresponding to any of the detection duty Db, the output current Ia, and the temperature T, the closest data may be used, or a known interpolation process may be used. For example, in the boost setting data (FIG. 10), when there is no data corresponding to the detected duty Db, the value closest to the detected duty Db among the duty candidates included in the boost setting data (FIG. 10). May be selected. The permissible range setting unit 12B may perform such a permissible range setting process only once during the boost mode, and may continue to use the obtained permissible range during the boost mode. It may be repeated during the mode, and the allowable range used (the allowable range used for the determination unit 12C) may be updated each time a new allowable range is obtained.

  The determination unit 12C outputs the input power Pb input via the second conductive path 92 (input side conductive path in the boost mode) and the first conductive path 91 (output side conductive path in the boost mode). The loss difference calculation process for calculating the loss difference (Pb−Pa) that is the difference from the output power Pa is continuously repeated. The calculation method of the loss difference (Pb−Pa) is the same as that in the first embodiment. Such loss difference calculation processing is repeatedly performed during the boost mode, and the loss difference (Pb−Pa) obtained by any loss difference calculation processing is outside the allowable range set by the allowable range setting unit 12B. Is determined to be abnormal. For example, the duty Db obtained based on the input voltage Vb and the output voltage Va detected by the voltage detector 20 during the boost mode is Db2, the output current Ia detected by the current detector 32 is Ia4, and the temperature When the temperature T detected by the detection unit 40 is T4, the allowable range setting unit 12B, based on the table data as shown in FIG. 9B, the data b244 corresponding to the duty Db2, the output current Ia4, and the detection temperature T4. The allowable range is specified by. The determination unit 12C continuously repeats the loss difference calculation process for calculating the loss difference (Pb−Pa) by the above-described method, and a situation has occurred in which the loss difference (Pb−Pa) exceeds the upper limit threshold determined by the data b244. In the case, it is determined as abnormal. The determination unit 12C also determines that an abnormality has occurred when a situation occurs in which the loss difference (Pb−Pa) falls below the lower limit threshold determined by the data b244. On the other hand, the determination unit 12C maintains the loss difference (Pb−Pa) below the upper limit threshold defined by the data b244 and above the lower limit threshold during the boost mode (from the start of the boost mode to switching to another mode). In this case, it is not determined as abnormal in the boost mode.

  The determination unit 12C performs a predetermined abnormality handling process when it is determined as abnormal in the above-described abnormality determination even in the step-down mode or the step-up mode. As the abnormality handling process, a predetermined notification process such as transmitting information indicating an abnormality to the host information processing apparatus may be performed, and a forced stop process for forcibly stopping the operation of the voltage conversion unit 6 May be performed.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.

In the first embodiment, an example in which the abnormality is determined when the difference between the input power and the output power is outside the allowable range has been described. However, when the ratio between the input power and the output power is outside the allowable range, the abnormality is determined. You may comprise. In the first embodiment, table data is used as setting data for determining the allowable range. However, an arithmetic expression for determining the allowable range may be used. 11 and 12 are explanatory diagrams regarding such an example, and FIG. 11A shows the relationship between the allowable range and the output current when the input voltage Va is Va1 (specifically, the upper limit threshold and the lower limit). The relationship between the threshold and the output current) is shown for each temperature. In FIG. 11B, the relationship between the allowable range and the output current when the input voltage Va is Va2 smaller than Va1 (the relationship between the upper and lower thresholds and the output current) is shown for each temperature. In this case, the setting data (FIG. 12) used in the allowable range setting unit 12B is prepared for each input voltage value as shown in FIGS. 11A and 11B. A set of a plurality of arithmetic expression data is formed.
The following description can be applied in the above-described step-up mode even in the above-described step-down mode. In the following description, the input power input to the voltage conversion unit 6 is P1, and output from the voltage conversion unit 6 The output power to be output is P2.
11 and 12, the “upper limit threshold” is the upper limit value of the ratio P2 / P1 (efficiency) of the output power P2 to the input power P1 in the voltage converter 6, and the “lower limit threshold” is the ratio P2 This is the lower limit value of / P1 (efficiency). 11 and 12, in each graph, a curve showing the relationship between the upper and lower thresholds when the temperature is T1 and the output current, and the upper and lower thresholds and the output current when the temperature is T2. In each graph prepared for each input voltage, data showing the relationship between the upper and lower thresholds and the output current for each temperature (FIGS. 11 and 12). Curves Z11, Z12, Z21, Z22, Z31, Z32, Z41, and Z42) are prepared for a large number of temperatures.
11A and 12, the relationship between the upper limit threshold value and the output current when the input voltage is Va1 and the temperature is T1 is indicated by a curve Z11, and the lower limit threshold value when the input voltage is Va1 and the temperature is T1. And the output current are indicated by a curve Z12. That is, when the input voltage is Va1 and the temperature detected by the temperature detector 40 is T1, the relationship between the output current and the upper limit threshold is an arithmetic expression indicating the curve Z11 (the output current (variable) and the upper limit as in the curve Z11). The relationship between the output current and the lower limit threshold value is specified by an arithmetic expression indicating the curve Z12 (the output current (variable) and the lower limit threshold value (variable) as in the curve Z12). Is specified by an arithmetic expression that defines the relationship. Similarly, the relationship between the upper limit threshold value and the output current at the input voltage Va1 and the temperature T2 is indicated by a curve Z21, and the relationship between the lower limit threshold value and the output current at the input voltage Va1 and the temperature T2 is indicated by a curve Z22. ing. In FIG. 11B, the relationship between the upper limit threshold value and the output current when the input voltage Va2 and the temperature T1 is indicated by a curve Z31, and the lower limit threshold value and the output current when the input voltage Va2 and the temperature T1 are set. The relationship is shown by a curve Z32. Further, the relationship between the upper limit threshold value and the output current when the input voltage is Va2 and the temperature T2 is indicated by a curve Z41, and the relationship between the lower limit threshold value and the output current when the input voltage is Va2 and the temperature is T2 is indicated by a curve Z42. Yes. Thus, for each combination of input voltage and temperature, data of an arithmetic expression indicating the relationship between the upper threshold and the output current and data of an arithmetic expression indicating the relationship between the lower threshold and the output current are prepared. If the voltage, temperature, and output current are determined, the upper threshold and the lower threshold can be specified.
The setting data shown in FIG. 12 has a data configuration in which the upper limit threshold of the allowable range increases and the lower limit threshold of the allowable range decreases as the temperature T detected by the temperature detection unit 40 increases. This setting data is, for example, as the temperature T detected by the temperature detection unit 40 increases, regardless of the combination of the input voltage Va and the output current Ib in the predetermined input voltage range and the predetermined output current range. The data sets the allowable range so that the upper limit threshold of the allowable range is increased and the lower limit threshold of the allowable range is decreased. Further, the setting data is stored in the current detection unit 32 (in step-down mode) regardless of the combination of the temperature T detected by the temperature detection unit 40 and the input voltage Va in a predetermined temperature range and the input voltage range. The upper limit threshold value of the allowable range decreases as the output current Ib detected by the output current detection unit) increases, and the allowable range is set such that the lower limit threshold value of the allowable range increases. Further, the setting data includes the upper limit of the allowable range as the input voltage Va increases regardless of the combination of the temperature T and the output current Ib detected by the temperature detection unit 40 in the temperature range and the output current range. The data sets the allowable range so that the threshold value increases and the lower limit threshold value of the allowable range decreases.
In this example, the determination unit 12C has a ratio P2 between the input power P1 input through the input side conductive path and the output power P2 output through the output side conductive path during execution of the step-down mode or the boost mode. The efficiency calculation process for calculating / P1 (efficiency) is continuously repeated. Then, when the efficiency (P2 / P1) obtained by any one of the efficiency calculation processes is out of the allowable range set by the allowable range setting unit 12B, it is determined as abnormal.
For example, when an abnormality is determined during the step-down mode, when the input voltage is Va1, the output current is Ib1 (100A), and the temperature T is T2 as shown in FIG. And the lower threshold is X2. In such an example, when the efficiency (P2 / P1) obtained by the efficiency calculation process exceeds the upper limit threshold X1, it is determined to be abnormal, and when the efficiency (P2 / P1) is less than the lower limit threshold X2, it is determined to be abnormal. Is done.

Instead of the examples shown in FIGS. 11 and 12, examples such as FIGS. 13 and 14 may be used. FIG. 13A shows the relationship between the allowable range and the output current when the detection duty Da is Da1 (specifically, the relationship between the upper and lower thresholds and the output current) for each temperature. FIG. 13B shows the relationship between the allowable range and the output current when the detection duty Da is Da2 (the relationship between the upper limit threshold and the lower limit threshold and the output current) for each temperature. In this case, the setting data (FIG. 14) used in the allowable range setting unit 12B is prepared for each detection duty value as shown in FIGS. 13A and 13B. A set of a plurality of arithmetic expression data is formed.
The following description can be applied in the above-described step-up mode even in the above-described step-down mode. In the following description, the input power input to the voltage conversion unit 6 is P1, and output from the voltage conversion unit 6 The output power to be output is P2.
In the examples of FIGS. 13 and 14, the “upper limit threshold” is the upper limit value of the ratio P2 / P1 (efficiency) of the output power P2 to the input power P1 in the voltage converter 6, and the “lower limit threshold” is the ratio P2 This is the lower limit value of / P1 (efficiency). 13 and 14, in each graph, a curve showing the relationship between the upper and lower thresholds when the temperature is T1, and the output current, and the upper and lower thresholds and the output current when the temperature is T2. In each of the graphs prepared for each input voltage, data indicating the relationship between the upper and lower thresholds and the output current for each temperature (FIGS. 13 and 14). Curves z11, z12, z21, z22, z31, z32, z41, and z42) are prepared for a number of temperatures.
13A and 14, the relationship between the upper limit threshold value and the output current when the detection duty is Da1 and the temperature is T1 is indicated by a curve z11, and the lower limit threshold value when the detection duty is Da1 and the temperature is T1. And the output current are indicated by a curve z12. That is, when the detection duty is Da1 and the temperature detected by the temperature detection unit 40 is T1, the relationship between the output current and the upper limit threshold is an arithmetic expression indicating the curve z11 (the output current (variable) and the upper limit as in the curve z11). The relation between the output current and the lower limit threshold value is specified by an arithmetic expression indicating the curve z12 (the output current (variable) and the lower limit threshold value (variable) as in the curve z12). Is specified by an arithmetic expression that defines the relationship. Similarly, the relationship between the upper limit threshold value and the output current when the detection duty is Da1 and the temperature T2 is indicated by a curve z21, and the relationship between the lower limit threshold value and the output current when the detection duty is Da1 and the temperature T2 is indicated by a curve z22. The relationship between the upper limit threshold value and the output current when the duty is Da2 and the temperature T1 is indicated by a curve z31 in FIG. 13B, and the relationship between the lower limit threshold value and the output current when the detection duty is Da2 and the temperature T1 is indicated by a curve z32. The relationship between the upper limit threshold value and the output current at the detection duty Da2 and the temperature T2 is indicated by a curve z41, and the relationship between the lower limit threshold value and the output current at the detection duty Da2 and the temperature T2 is indicated by a curve z42. In this way, for each combination of detection duty and temperature, data of an arithmetic expression indicating the relationship between the upper limit threshold value and the output current and data of an arithmetic expression indicating the relationship between the lower limit threshold value and the output current are prepared. If the duty, temperature, and output current are determined, the upper threshold and the lower threshold can be specified.
The setting data shown in FIG. 14 has a data configuration in which the upper limit threshold of the allowable range increases and the lower limit threshold of the allowable range decreases as the temperature T detected by the temperature detection unit 40 increases. For example, the setting data is more acceptable as the temperature T detected by the temperature detection unit 40 increases, regardless of the combination of the detection duty Da and the output current Ib in the predetermined duty range and the predetermined output current range. The data sets the allowable range so that the upper limit threshold of the range is increased and the lower limit threshold of the allowable range is decreased. Further, the setting data is obtained from the current detection unit 32 (in step-down mode) regardless of the combination of the temperature T detected by the temperature detection unit 40 and the detection duty Da within a predetermined temperature range and the duty range. The upper limit threshold value of the allowable range decreases as the output current Ib detected by the output current detection unit) increases, and the allowable range is set such that the lower limit threshold value of the allowable range increases.
Also in this example, the determination unit 12C has a ratio P2 between the input power P1 input through the input side conductive path and the output power P2 output through the output side conductive path during the execution of the step-down mode or the boost mode. The efficiency calculation process for calculating / P1 (efficiency) is continuously repeated. Then, when the efficiency (P2 / P1) obtained by any one of the efficiency calculation processes is out of the allowable range set by the allowable range setting unit 12B, it is determined as abnormal. For example, when performing abnormality determination during the step-down mode, when the detection duty is Da1, the output current is Ib1 (100A), and the temperature T is T2, as shown in FIG. And the lower threshold is X2. In such an example, when the efficiency (P2 / P1) obtained by the efficiency calculation process exceeds the upper limit threshold X1, it is determined to be abnormal, and when the efficiency (P2 / P1) is less than the lower limit threshold X2, it is determined to be abnormal. Is done.

  In the first embodiment, the bidirectional step-up / step-down DCDC converter is illustrated as an example of the in-vehicle power supply device. However, in any example in which the first embodiment or the first embodiment is changed, the step-down DCDC converter may be used. It may be a step-up DCDC converter or a step-up / step-down DCDC converter. Further, as in the first embodiment, a bidirectional DCDC converter that can change the input side and the output side may be used, or a unidirectional DCDC converter in which the input side and the output side are fixed. .

  In the first embodiment, the single-phase DCDC converter is exemplified. However, in any example in which the first embodiment or the first embodiment is changed, a multiphase DCDC converter may be used.

  In the first embodiment, the synchronous rectification type DCDC converter is exemplified. However, in any example in which the first embodiment or the first embodiment is changed, a diode-type DCDC converter in which some switching elements are replaced with diodes may be used. .

  In the first embodiment, the switching elements S1, S2, S3, and S4 configured as N-channel MOSFETs are exemplified as the switching elements of the in-vehicle power supply device. However, any example in which the first embodiment or the first embodiment is changed is described. In this case, the switching element may be a P-channel MOSFET or another switching element such as a bipolar transistor.

  In the first embodiment, the control unit 12 is mainly configured by a microcomputer. However, in any example in which the first embodiment or the first embodiment is changed, the control unit 12 may be realized by a plurality of hardware circuits other than the microcomputer. Good.

DESCRIPTION OF SYMBOLS 1 ... Vehicle-mounted power supply device 6 ... Voltage conversion part 8 ... Drive part 10 ... Vehicle-mounted abnormality detection apparatus 12 ... Control part 12A ... Calculation part 12B ... Permissible range setting part 12C ... Determination part 20 ... Voltage detection part 21 ... Voltage detection (Input voltage detector, output voltage detector)
22 ... Voltage detector (input voltage detector, output voltage detector)
30 ... Current detection unit 31 ... Current detection unit (input current detection unit, output voltage detection unit)
32 ... Current detector (input current detector, output voltage detector)
40 ... temperature detection unit 91 ... first conductive path (input side conductive path, output side conductive path)
92 ... 2nd conductive path (input side conductive path, output side conductive path)
S1, S2, S3, S4 ... switching elements

Claims (8)

A switching element that performs an on / off operation in response to a control signal that is alternately switched between an on signal and an off signal is provided, and the voltage applied to the input side conductive path is boosted or lowered by the on / off operation of the switching element and output. A voltage converter that outputs to the side conductive path;
A voltage detection unit including an input voltage detection unit that detects an input voltage applied to the input side conductive path; and an output voltage detection unit that detects an output voltage applied to the output side conductive path;
A current detection unit including an input current detection unit that detects an input current flowing through the input side conductive path; and an output current detection unit that detects an output current flowing through the output side conductive path;
A calculation unit that repeats a feedback calculation that calculates the duty of the control signal so that the voltage of the output-side conductive path approaches a target voltage value based on at least the output voltage detected by the output voltage detection unit;
A drive unit that outputs the control signal of the duty calculated by the calculation unit to the switching element;
An abnormality detection device for detecting an abnormality of a vehicle-mounted power supply device comprising:
An allowable range setting unit for setting an allowable range used for abnormality determination;
The input power input to the voltage conversion unit via the input side conductive path, the output power output from the voltage conversion unit via the output side conductive path, and the allowable range setting unit A determination unit for determining an abnormality based on an allowable range;
Have
The allowable range setting unit detects an abnormality of the in-vehicle power supply device that sets the allowable range based on at least one of a voltage detected by the voltage detection unit or a current detected by the current detection unit apparatus. A switching element that performs an on / off operation in response to a control signal that is alternately switched between an on signal and an off signal is provided, and the voltage applied to the input side conductive path is boosted or lowered by the on / off operation of the switching element and output. A voltage converter that outputs to the side conductive path;
A voltage detection unit including an input voltage detection unit that detects an input voltage applied to the input side conductive path; and an output voltage detection unit that detects an output voltage applied to the output side conductive path;
A current detection unit including an input current detection unit that detects an input current flowing through the input side conductive path; and an output current detection unit that detects an output current flowing through the output side conductive path;
A temperature detector for detecting the temperature at a predetermined position in the vehicle;
A calculation unit that repeats a feedback calculation that calculates the duty of the control signal so that the voltage of the output-side conductive path approaches a target voltage value based on at least the output voltage detected by the output voltage detection unit;
A drive unit that outputs the control signal of the duty calculated by the calculation unit to the switching element;
An abnormality detection device for detecting an abnormality of a vehicle-mounted power supply device comprising:
An allowable range setting unit for setting an allowable range used for abnormality determination;
The input power input to the voltage conversion unit via the input side conductive path, the output power output from the voltage conversion unit via the output side conductive path, and the allowable range setting unit A determination unit for determining an abnormality based on an allowable range;
Have
The said tolerance | permissible_range setting part is an abnormality detection apparatus of the vehicle-mounted power supply device which sets the said tolerance | permissible_range based on the temperature detected by the said temperature detection part at least.   The in-vehicle use according to claim 2, wherein the allowable range setting unit sets the allowable range such that the difference between the upper limit threshold and the lower limit threshold of the allowable range increases as the temperature detected by the temperature detection unit increases. Abnormality detection device for power supply.   The abnormality detection device for an in-vehicle power supply device according to claim 2 or 3, wherein the temperature detection unit includes a temperature sensor mounted on a substrate on which components constituting the voltage conversion unit are mounted.   The determination unit is configured such that the difference between the input power input through the input side conductive path and the output power output through the output side conductive path is the allowable range set by the allowable range setting unit. The abnormality detection device for an in-vehicle power supply device according to any one of claims 1 to 4, wherein an abnormality is determined when the value is out of range.   The said tolerance | permissible_range setting part sets the said tolerance | permissible_range so that the difference between the upper limit threshold value of the said tolerance | permissible_range and a minimum threshold value may become so small that the said output current detected by the said output current detection part becomes large. The abnormality detection device for an in-vehicle power supply device according to any one of items 5 to 6.   The said tolerance | permissible_range setting part sets the said tolerance | permissible_range so that the difference of the upper limit threshold value of the said tolerance | permissible_range and a minimum threshold value may become so large that the said input voltage detected by the said input voltage detection part becomes large. The abnormality detection device for an in-vehicle power supply device according to any one of Items 6.   The abnormality detection device according to claim 1, the voltage conversion unit, the input voltage detection unit, the output voltage detection unit, the input current detection unit, and the output current. An in-vehicle power supply device comprising a detection unit, the calculation unit, and the drive unit.

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