JP7087846B2 - Power storage system - Google Patents

Description

The present disclosure relates to a power storage system, and more particularly to a power storage system including a temperature sensor.

For example, Japanese Patent Application Laid-Open No. 2017-187397 (Patent Document 1) discloses a power storage system including two temperature sensors. In this power storage system, the negative electrode and the positive electrode of the power storage device are connected to the first relay and the second relay, respectively. When the power storage device is discharged and charged, a current flows through the first relay and the second relay, and the first relay and the second relay generate heat. A temperature sensor is provided in each of the first relay and the second relay, and the temperature of each relay is monitored so as not to rise excessively. By limiting the current before the temperature of either the first relay or the second relay becomes too high, the heat generation of the first relay and the second relay is suppressed.

JP-A-2017-187397

By monitoring the temperature of the component with a temperature sensor, it is possible to protect the component before the temperature of the component becomes too high (for example, to execute a process of suppressing heat generation of the component). However, if an abnormality occurs in the temperature sensor, it may not be possible to properly protect the parts. In order to properly protect the parts, it is required to accurately detect the abnormality of the temperature sensor.

As a method for detecting an abnormality in a temperature sensor, for example, it is determined whether or not the deviation between the detected values of the two temperature sensors is large, and if the deviation is large, an abnormality has occurred in at least one of the two temperature sensors. A method of determining that is conceivable.

However, when the abnormality of the temperature sensor that detects the temperature of the component provided in the power path of the power storage device is detected by the above method, the abnormality of the temperature sensor is detected with high accuracy depending on the situation in which the determination based on the deviation is performed. There are things you can't do. For example, in the power storage system described in Patent Document 1, the first relay and the second relay are provided in the power path of the power storage device, and the first relay and the second relay are provided at the time of discharging and the time of charging of the power storage device, respectively. It becomes energized and generates heat. At this time, if the amount of heat generated by each relay is different, the temperature difference between the relays becomes large. Therefore, when the deviation of the detection values of the two temperature sensors provided in each relay becomes large in the situation where the first relay and the second relay are energized, the cause is the detection error of the temperature sensor. It is difficult to determine whether it is due to the difference in the amount of heat generated by each relay. Further, since the method of generating heat of a component (relay or the like) used in an electric circuit tends to change with the passage of time, it is difficult to accurately determine the amount of heat generated by the component. In general, the parts tend to generate heat as time passes due to an increase in resistance due to deterioration, but the deterioration rate of the parts changes depending on how they are used.

The present disclosure has been made to solve the above problems, and an object thereof is to detect an abnormality of a temperature sensor for detecting the temperature of a component provided in a power path of a power storage device with high accuracy.

The power storage system of the present disclosure determines the temperature of the power storage device, the first component and the second component provided in the power path of the power storage device, the first temperature sensor for detecting the temperature of the first component, and the temperature of the second component. A second temperature sensor for detection and a sensor abnormality detection device are provided. Then, when the sensor abnormality detecting device satisfies a predetermined condition including that the temperature of each of the first component and the second component is stabilized after the first component and the second component are changed from the energized state to the non-energized state. In addition, the temperature of the first component detected by the first temperature sensor (hereinafter, also referred to as “first detected temperature”) and the temperature of the second component detected by the second temperature sensor (hereinafter, also referred to as “second detected temperature”). In addition to acquiring (referred to as), the temperature deviation between the first detected temperature and the second detected temperature is used to determine whether or not an abnormality has occurred in at least one of the first temperature sensor and the second temperature sensor. It is composed.

In the above power storage system, when the temperature of each component stabilizes after the first component and the second component are changed from the energized state to the non-energized state, the detection values of the respective temperature sensors (first detection temperature and second detection temperature). Is obtained, and the presence or absence of an abnormality in the sensor is determined using those temperature deviations. That is, even if the first component and the second component provided in the power path of the power storage device are energized and generate heat, the presence or absence of an abnormality in the sensor is determined by the temperature of each of the first component and the second component. It is performed after it stabilizes (that is, when it is sufficiently cold). Therefore, the fluctuation of the temperature deviation caused by the difference in the heat generation characteristics (ease of heat generation) of the first component and the second component is suppressed, and the abnormality of the temperature sensor can be detected with high accuracy.

The deviation is a parameter indicating the deviation (degree of difference) between the two values. As the deviation, a difference, a ratio, or the like can be adopted. The larger the difference (absolute value), the larger the deviation. Further, the closer the ratio is to 1, the smaller the deviation.

The power path of the power storage device may be a charging path or a discharging path. Further, the power path of the power storage device may function as both a charging path and a discharging path. Each of the first component and the second component provided in the power path of the power storage device is energized at least one of the time of discharging and the time of charging of the power storage device.

According to the present disclosure, it becomes possible to accurately detect an abnormality of a temperature sensor that detects the temperature of a component provided in a power path of a power storage device.

FIG. 3 is a block diagram schematically showing an overall configuration of a vehicle to which the power storage system according to the first embodiment of the present disclosure is applied. It is a figure which shows the internal structure of the 1st junction box. It is a figure which shows the internal structure of the 2nd junction box. It is a flowchart which shows the processing procedure of abnormality detection of the temperature sensor executed by the control device of the power storage system which concerns on Embodiment 1 of this disclosure. It is a figure which shows the normal range and the abnormal range of the temperature deviation between the 1st detection temperature and the 2nd detection temperature in Embodiment 1 of this disclosure. It is a timing chart which shows an example of each transition of the counter value, the state of IGSW (ignition switch), and the state of SMR (system main relay) in the process of FIG. It is a flowchart which shows the processing procedure of abnormality detection of the temperature sensor executed by the control device of the power storage system which concerns on Embodiment 2 of this disclosure. It is a figure which shows an example of each transition of the 1st detection temperature and the 2nd detection temperature in Embodiment 2 of this disclosure. It is a flowchart which shows the processing procedure of abnormality detection of the temperature sensor executed by the control device of the power storage system which concerns on Embodiment 3 of this disclosure.

Embodiments of the present disclosure will be described in detail with reference to the drawings. The same or corresponding parts in the drawings are designated by the same reference numerals and the description thereof will not be repeated.

In the following, an example in which the power storage system is applied to a hybrid vehicle will be described. However, the application target of the power storage system is not limited to the hybrid vehicle, and may be an electric vehicle not equipped with an engine. Further, the use of the power storage system is not limited to that for vehicles, and may be for stationary use.

[Embodiment 1]
FIG. 1 is a block diagram schematically showing an overall configuration of a vehicle 1 to which the power storage system according to the first embodiment is applied. The vehicle 1 according to this embodiment corresponds to an example of the "power storage system" according to the present disclosure.

With reference to FIG. 1, the vehicle 1 includes a battery pack 2, motor generators (hereinafter referred to as “MG”) 11, 12, an engine 20, a drive wheel 30, a power dividing device 31, and a drive shaft 32. A power control unit (hereinafter referred to as "PCU") 40, an electronic control unit (hereinafter referred to as "ECU") 300, a notification device 400, and an ignition switch (hereinafter referred to as "IGSW") 500. To prepare for.

The battery pack 2 includes a battery 100, a junction box (hereinafter referred to as “JB”) 50, 60, a voltage sensor 210, a current sensor 220, a temperature sensor 230, and a cooling device 240.

The battery 100 is a DC power source configured to be rechargeable. The battery 100 includes an assembled battery composed of a plurality of secondary batteries. As the secondary battery, for example, a lithium ion battery can be adopted. However, the present invention is not limited to this, and other secondary batteries (nickel-metal hydride batteries, etc.) may be adopted. Further, the secondary battery may be an all-solid-state battery. The battery 100 according to this embodiment corresponds to an example of the "power storage device" according to the present disclosure.

The JB 50 includes a system main relay (hereinafter referred to as “SMR-B”) 51 electrically connected to the positive electrode of the battery 100, and a temperature sensor 52 that detects the temperature of the SMR-B 51. The JB 60 includes a system main relay (hereinafter referred to as “SMR-G”) 61 electrically connected to the negative electrode of the battery 100, and a temperature sensor 62 that detects the temperature of the SMR-G 61. The SMR-B51, SMR-G61, temperature sensor 52, and 62 according to this embodiment are the "first component", "second component", "first temperature sensor", and "second temperature sensor", respectively, according to the present disclosure. Corresponds to an example.

The JBs 50 and 60 include various parts (relays, fuses, etc.) included in the battery pack 2, and are configured to electrically connect these parts. JB50,60 enables centralized connection of electric circuits. Although not shown in FIG. 1, the JBs 50 and 60 also have a built-in charging relay (for example, charging relays 53 and 63 shown in FIGS. 2 and 3 described later) provided in the charging path of the battery 100. The charging relay is ON / OFF controlled by the ECU 300, and becomes an ON state (conduction state) when charging by a power source outside the vehicle, and becomes an OFF state (cutoff state) when charging is completed. Further, the JBs 50 and 60 may further include an S / P (service / plug), a fuse box, a PN (positive / negative) connector and the like. The PN connector is a two-pole connector that connects the positive and negative electrodes of the battery 100 to the PCU 40 (for example, an inverter).

FIG. 2 is a diagram showing the internal structure of the JB50. With reference to FIG. 2, the SMR-B51 and the charging relay 53 are built in the JB50, for example, as shown in FIG. Further, although not shown in FIG. 2, a temperature sensor 52 (FIG. 1) is provided in the vicinity of the SMR-B51.

FIG. 3 is a diagram showing the internal structure of JB60. With reference to FIG. 3, the SMR-G61 and the charging relay 63 are built in the JB 60, for example, as shown in FIG. Further, although not shown in FIG. 3, a temperature sensor 62 (FIG. 1) is provided in the vicinity of the SMR-G61.

As each relay (SMR-B51, SMR-G61, and charging relay 53, 63) provided in the JB 50, 60, for example, an electromagnetic mechanical relay can be adopted. However, the present invention is not limited to this, and a semiconductor relay also called an SSR (Solid State Relay) may be adopted. Examples of semiconductor relays include thyristors, triacs, or relays composed of transistors (IGBTs, MOSFETs, bipolar transistors, etc.).

With reference to FIG. 1 again, the SMR-B51 and the SMR-G61 are provided in the power path of the battery 100 (more specifically, the power line connecting the battery 100 and the PCU 40), and are ON / OFF controlled by the ECU 300. .. The power line connecting the battery 100 and the PCU 40 can function as both a charging path and a discharging path of the battery 100. The two system main relays (SMR-B51 and SMR-G61) are driven simultaneously or in a predetermined order so that they are in the same state (ON state or OFF state), and are turned ON / OFF according to the operation of, for example, the IGSW500. The state switches. When the IGSW500 is turned on, each system main relay is turned on, and when the IGSW500 is turned off, each system main relay is turned off. Hereinafter, the state where the IGSW500 is in the ON state may be referred to as “READY-ON”, and the state where the IGSW500 is in the OFF state may be referred to as “READY-OFF”. When READY-ON (that is, when SMR-B51 and SMR-G61 are in the ON state), the power path of the battery 100 is connected, and the battery 100 is charged and discharged (and thus between the battery 100 and the PCU 40). (Transmission and reception of electric power) becomes possible. On the other hand, when READY-OFF (that is, when SMR-B51 and SMR-G61 are in the OFF state), the power path of the battery 100 is cut off, and the battery 100 cannot be charged or discharged.

The PCU 40 executes bidirectional power conversion between the battery 100 and the MGs 11 and 12 according to a control signal from the ECU 300. The PCU 40 is configured so that the states of the MGs 11 and 12 can be controlled separately. For example, the MG12 can be put into a power running state while the MG11 is in a regenerative (power generation) state. The PCU 40 includes, for example, two inverters provided corresponding to MGs 11 and 12, and a converter that boosts the DC voltage supplied to each inverter to a voltage higher than the output voltage of the battery 100.

The MGs 11 and 12 are AC rotary electric machines, for example, three-phase AC synchronous motors in which a permanent magnet is embedded in a rotor. The MG 11 is mainly used as a generator driven by the engine 20 via the power splitting device 31. The electric power generated by the MG 11 is supplied to the MG 12 or the battery 100 via the PCU 40.

The MG 12 mainly operates as an electric motor and drives the drive wheels 30. The MG 12 is driven by receiving at least one of the electric power from the battery 100 and the electric power generated by the MG 11, and the driving force of the MG 12 is transmitted to the drive shaft 32. On the other hand, when the vehicle 1 is braking or the acceleration is reduced on a downhill slope, the MG 12 operates as a generator to generate regenerative power generation. The electric power generated by the MG 12 is supplied to the battery 100 via the PCU 40.

The engine 20 is an internal combustion engine that outputs power by converting the combustion energy generated when a mixture of air and fuel is burned into the kinetic energy of a mover such as a piston or a rotor. The power splitting device 31 includes, for example, a planetary gear mechanism having three rotation axes of a sun gear, a carrier, and a ring gear. The power splitting device 31 divides the power output from the engine 20 into a power for driving the MG 11 and a power for driving the drive wheels 30.

The voltage sensor 210 detects the voltage of the battery 100. The current sensor 220 detects the current input / output to / from the battery 100. The temperature sensor 230 detects the temperature of the battery 100. Each sensor outputs the detection result to the ECU 300. The voltage sensor 210 and the temperature sensor 230 may be independently provided one by one for each cell, one may be provided for each of a plurality of cells, or one assembled battery may be provided. Only one may be provided for each.

The cooling device 240 is mainly configured to cool the battery 100. However, when the cooling device 240 is driven, the JBs 50, 60 and the like existing around the battery 100 are also cooled. The cooling device 240 is controlled by the ECU 300. In this embodiment, a blower is adopted as the cooling device 240. The blower is configured to blow outside air taken in from an intake port (not shown) to the battery 100 to cool the battery 100 and its surroundings. The blower may be a fan or a blower. By increasing the driving amount of the blower, the rotation speed of the impeller of the blower increases. When the rotation speed of the impeller of the blower device increases, the amount of blown air (air volume) increases, and the battery 100 and the like are easily cooled.

The ECU 300 includes a CPU (Central Processing Unit) 301, a memory 302, and an input / output buffer (not shown). The memory 302 includes a ROM (Read Only Memory), a RAM (Random Access Memory), and a rewritable non-volatile memory. Various controls are executed by the CPU 301 executing the program stored in the memory 302 (for example, ROM). The detection values of various sensors (temperature sensors 52, 62, etc.) are input to the ECU 300. Then, the ECU 300 controls various devices so that the vehicle 1 is in a desired state based on the signals received from the various sensors and the map and the program stored in the memory 302. The ECU 300 executes running control of the vehicle 1 and charge / discharge control of the battery 100 by controlling various parts (SMR-B51, SMR-G61, etc.) in the engine 20, the PCU 40, and the JB 50, 60, for example. The various controls performed by the ECU 300 are not limited to software processing, but can also be processed by dedicated hardware (electronic circuits). The ECU 300 according to this embodiment corresponds to an example of the "sensor abnormality detection device" according to the present disclosure.

The notification device 400 is configured to perform a predetermined notification process to the user when a request is received from the ECU 300. Examples of the notification device 400 include a display device, a speaker, and a lamp. Further, a mobile device (smartphone or the like) may be adopted as the notification device 400.

The IGSW500 is turned on / off by a user (eg, a driver). When the IGSW500 is operated, a signal indicating the state (ON state / OFF state) of the IGSW500 is output from the IGSW500 to the ECU 300. Then, according to the operation of the IGSW500, the start / stop of the traveling drive unit (for example, MG12 and the engine 20) of the vehicle 1 is switched. The signal indicating that the IGSW500 is in the ON state (that is, READY-ON) corresponds to the start request of the traveling drive unit, and the signal indicating that the IGSW500 is in the OFF state (that is, READY-OFF) corresponds to the traveling drive. Corresponds to a request to stop the unit. When the IGSW500 is turned on, the ECU 300 executes start control of the traveling drive unit, and when the IGSW500 is turned off, the ECU 300 executes stop control of the traveling drive unit. Each of SMR-B51 and SMR-G61 is turned on by the start control of the traveling drive unit, and each of SMR-B51 and SMR-G61 is turned off by the stop control of the traveling drive unit.

By the way, two system main relays (SMR-B51, SMR-G61) are mounted on the vehicle 1 (storage system) according to this embodiment, and temperature sensors (temperature sensors 52, 62) are mounted on each system main relay. ) Is provided. Each system main relay is individually replaced or repaired according to the degree of deterioration. When the SMR-B51 and the SMR-G61 deteriorate at different speeds, one with a faster deterioration rate may be replaced or repaired first, and the other with a slower deterioration rate may be used as it is. As the degree of deterioration of the system main relay increases, the resistance increases and heat generation tends to occur. For example, if only SMR-B51 out of SMR-B51 and SMR-G61 is replaced with a new one, SMR-G61 is more likely to generate heat than SMR-B51.

When the battery 100 is discharged and charged, the SMR-B51 and the SMR-G61 provided in the power path of the battery 100 are energized and generate heat. At this time, if the amount of heat generated by each system main relay is different, the temperature difference between the relays becomes large. Therefore, when the deviation of the detected values of the two temperature sensors 52 and 62 provided in each system main relay becomes large in the situation where the SMR-B51 and the SMR-G61 are energized, the cause is the temperature sensor. It is difficult to determine whether it is due to the detection error of 52 or 62 or the difference in the calorific value of each system main relay. Moreover, since the method of heat generation of the system main relay tends to change with the passage of time, it is difficult to accurately determine the heat generation amount of the system main relay. The deterioration rate of the system main relay changes depending on how it is used.

Therefore, in the vehicle 1 (power storage system) according to this embodiment, it is determined that the temperatures of the SMR-B51 and the SMR-G61 are stable after the SMR-B51 and the SMR-G61 are changed from the energized state to the non-energized state. When a predetermined condition including the above condition (hereinafter, also referred to as “determination condition”) is satisfied, the presence or absence of abnormality in the temperature sensors 52 and 62 is determined by using the deviation of the detected values of the temperature sensors 52 and 62. Stable temperature of each of SMR-B51 and SMR-G61 after the SMR-B51 and SMR-G61 are changed from the energized state to the non-energized state is a necessary requirement (necessary condition) for the determination condition to be satisfied. Therefore, even if the SMR-B51 and SMR-G61 provided in the power path of the battery 100 are energized and generate heat, the presence or absence of abnormality in the temperature sensors 52 and 62 can be determined by the SMR-B51 and SMR-G61. It is performed after each temperature of the above stabilizes (that is, when the temperature becomes sufficiently low). As a result, fluctuations in temperature deviation due to differences in heat generation characteristics (ease of heat generation) between SMR-B51 and SMR-G61 are suppressed, and abnormalities in the temperature sensors 52 and 62 can be detected with high accuracy. ..

FIG. 4 is a flowchart showing a processing procedure for detecting an abnormality in a temperature sensor executed by the ECU 300 of the power storage system according to the first embodiment of the present disclosure. The process shown in this flowchart is called and executed from the main routine (not shown) when a predetermined condition is satisfied. However, when the process of FIG. 4 is started, the state of the vehicle 1 is READY-ON. In READY-ON, the system main relays (SMR-B51 and SMR-G61) are in the ON state. The control period is, for example, about 100 ms.

With reference to FIG. 4, in step 11 (hereinafter, also simply referred to as “S”) 11, whether or not the state of the vehicle 1 has changed from READY-ON to READY-OFF (that is, the IGSW500 is turned off by the user's operation). Whether or not it is) is determined by the ECU 300. Then, while it is determined that READY-ON is maintained (NO in S11), the processing of S11 is repeated every control cycle.

When it is determined in S11 that the state of the vehicle 1 has become READY-OFF (YES in S11), the ECU 300 turns off each of SMR-B51 and SMR-G61 in S12. As a result, the power path of the battery 100 is cut off, and each of the SMR-B51 and the SMR-G61 is in a non-energized state.

Subsequently, the ECU 300 sets 0 as an initial value in the counter C1 in S13. The counter C1 is a parameter indicating the elapsed time since both the SMR-B51 and the SMR-G61 are in the non-energized state, and is prepared in advance in the memory 302, for example.

Subsequently, the ECU 300 determines in S14 whether or not the state of the vehicle 1 has changed from READY-OFF to READY-ON (that is, whether or not the IGSW500 has been turned on by the user's operation). When it is determined that the state of the vehicle 1 is READY-OFF (NO in S14), the value of the counter C1 is incremented by counting up (+1) the counter C1 in the memory 302 in S15. Update. While READY-OFF is maintained, the processes of S14 and S15 are repeated every control cycle.

When it is determined in S14 that the state of the vehicle 1 is READY-ON (YES in S14), the ECU 300 determines in S161 to S163 whether or not the determination condition is successful. In the example of FIG. 4, it is a necessary and sufficient condition for the determination condition to be satisfied that YES is determined in all of S161 to S163. The determination of the presence or absence of an abnormality in S17 is executed only when YES is determined in all of S161 to S163.

In S161, it is determined whether or not the counter C1 is equal to or greater than a predetermined value. The predetermined value used in S161 is set so that the counter C1 becomes equal to or higher than the predetermined value when the temperatures of SMR-B51 and SMR-G61 are stable. More specifically, as the predetermined value used in S161, after the SMR-B51 and SMR-G61 that have once generated heat in the energized state are de-energized, the SMR-B51 and SMR-G61 are maintained in the non-energized state. Then, the time (count number) required for the temperatures of SMR-B51 and SMR-G61 to stabilize (for example, to be about the same as the outside air temperature) is set. Such time (and by extension, the above-mentioned predetermined value) is obtained in advance by an experiment or the like and stored in the memory 302. The predetermined value used in S161 may be a fixed value or may be variable according to the sensor maximum temperature or the like described later.

In S162, it is determined whether or not the wiring of the temperature sensors 52 and 62 is disconnected or short-circuited. For example, when the output value of at least one of the temperature sensors 52 and 62 is fixed to the upper limit or the lower limit, it is determined that a disconnection or a short circuit has occurred (NO in S162).

In S163, it is determined whether or not the detected values of the temperature sensors 52 and 62 are normally output. More specifically, it is determined whether or not the output value of each sensor fluctuates normally, and whether or not the output value of each sensor is within the normal range. For example, when the output value of at least one of the temperature sensors 52 and 62 is abnormally large or abnormally small, it is determined as NO in S163. Further, even when the output value of at least one of the temperature sensors 52 and 62 does not fluctuate normally (that is, when an output fixing abnormality occurs), NO is determined in S163.

If it is determined to be YES in all of S161 to S163, the ECU 300 determines that the determination condition is satisfied, acquires the detection values of the temperature sensors 52 and 62 in S17, and uses their temperature deviations. It is determined whether or not an abnormality has occurred in at least one of the temperature sensors 52 and 62. In the example of FIG. 4, as the temperature deviation, the temperature of the SMR-B51 detected by the temperature sensor 52 (hereinafter, also referred to as “T1”) and the temperature of the SMR-G61 detected by the temperature sensor 62 (hereinafter, “T2””. Also called) and the difference (absolute value) is adopted. In S17, it is determined whether or not the temperature difference | T1-T2 | is equal to or greater than a predetermined value (hereinafter, also referred to as “threshold value X”). T1 and T2 according to this embodiment correspond to examples of the "first detection temperature" and the "second detection temperature" according to the present disclosure, respectively.

The threshold value X used in S17 is a threshold value for detecting an abnormality in the sensor, and is, for example, obtained in advance by an experiment or the like and stored in the memory 302. The threshold value X is a predetermined period of a predetermined sensor among the temperature sensors 52 and 62 (for example, a period from when the state of the vehicle 1 becomes READY-ON until it is determined in S11 that the state becomes READY-OFF). It may be variable based on the maximum value of the detected temperature in (hereinafter, also referred to as “sensor maximum temperature”). The predetermined sensor may be a temperature sensor 52, a temperature sensor 62, or both of the temperature sensors 52 and 62. As an example of the sensor maximum temperature of both the temperature sensors 52 and 62, the average value of the maximum detected temperatures of each sensor can be mentioned. When the maximum detection temperature of each sensor is low, the temperature deviation between the sensors after cooling tends to be large. Therefore, in S17, when the maximum sensor temperature is low, the threshold value X is higher than when the maximum sensor temperature is high. May be increased. For example, by storing information (formula, map, etc.) indicating the relationship between the sensor maximum temperature and the threshold value X in advance in the memory 302, in S17, the ECU 300 refers to such information to reach the sensor maximum temperature. It becomes possible to set the corresponding threshold value X. The threshold value X may be variable, for example, in the range of 20 ° C to 70 ° C. The lower the sensor maximum temperature, the larger the threshold value X may be. However, the present invention is not limited to the above, and the threshold value X used in S17 may be a fixed value.

FIG. 5 is a diagram showing a normal range and an abnormal range of T1-T2. In FIG. 5, the horizontal axis represents T1-T2, and x corresponds to the threshold value for sensor abnormality detection (that is, the threshold value X used in S17). With reference to FIG. 5, "-p to + p" indicates a normal range, and "-x or less" and "+ x or more" each indicate an abnormal range. In S17, T1-T2 is acquired for each control cycle, and when T1-T2 is continuously present in "-p to + p" for a predetermined time (for example, 1 second to 10 seconds), it is determined to be YES, and T1 is determined. If -T2 is continuously present for a predetermined time (for example, 1 to 10 seconds) at "-x or less" or "+ x or more", it is determined as NO.

It should be noted that the center position of the normal range in the temperature deviation (for example, temperature difference) does not always have no deviation (for example, temperature difference = 0 ° C.). For example, depending on the mounting position of the temperature sensors 52 and 62, the normal range may be biased to either the + side or the-side. Further, the temperature deviation is not limited to the above temperature difference, and is arbitrary as long as it represents a deviation (degree of difference) between the two detected values (first detected temperature and second detected temperature). For example, the ratio of T1 to T2 (T1 / T2 or T2 / T1) may be adopted as the temperature deviation.

With reference to FIG. 4 again, if NO is determined in S17, the ECU 300 determines that the temperature sensors 52 and 62 are normal, and turns on each of SMR-B51 and SMR-G61 in S181. As a result, the power path of the battery 100 is connected, and each of the SMR-B51 and the SMR-G61 is energized. Then, when the process of S181 is executed, the process of FIG. 4 ends, and the process is returned to the main routine.

If NO is determined in S161, the ECU 300 determines that the determination condition is not satisfied, and the process proceeds to S181 without going through S17.

If YES is determined in S17, the ECU 300 determines that an abnormality has occurred in at least one of the temperature sensors 52 and 62, and executes a predetermined fail-safe process in S182. In the example of FIG. 4, it is not specified which of the temperature sensors 52 and 62 has an abnormality. However, the present invention is not limited to this, and the ECU 300 may be configured to specify which of the temperature sensors 52 and 62 has an abnormality based on the output values of the temperature sensors 52 and 62 and the like.

The fail-safe process includes at least one of notifying that a sensor abnormality has occurred, recording that a sensor abnormality has occurred, limiting the current of the battery 100, and increasing the drive amount of the cooling device 240. You may. In this embodiment, all of these are performed, as described below.

In S182, the ECU 300 controls the notification device 400 to notify the user that a sensor abnormality has occurred. The method of notifying the user is arbitrary, characters or images may be displayed on the display device, sound (including voice) may be notified by a speaker, or a predetermined lamp (for example, MIL (failure)) may be notified. The warning light)) may be turned on (including blinking).

In S182, recording that a sensor abnormality has occurred is performed. For example, the ECU 300 records in the memory 302 that a sensor abnormality has occurred by turning on the diagnosis (self-diagnosis) flag in the memory 302 (changing the value of the flag from 0 to 1).

In S182, the current of the battery 100 is limited. For example, the ECU 300 controls the PCU 40 and the like so that the input / output current of the battery 100 does not exceed a predetermined limit value. By performing such current limitation, heat generation of SMR-B51 and SMR-G61 is suppressed. Further, when the current limit is performed even in the situation where the sensor abnormality does not occur, the current limit is strengthened by reducing the limit value by the ECU 300 when the sensor abnormality occurs (YES in S17). May be good.

In S182, the driving amount of the cooling device 240 is maximized. In the ECU 300, the rotation speed of the impeller of the cooling device 240 (for example, a fan or a blower) increases. As a result, the amount of air blown to the battery 100 increases, and the battery 100 and its surroundings, such as JB50 and 60, are easily cooled.

Further, even when NO is determined in either S162 or S163, the ECU 300 determines that an abnormality has occurred in at least one of the temperature sensors 52 and 62, and executes the fail-safe process in S182. It should be noted that different fail-safe processes may be executed depending on whether it is determined to be YES in S17, NO in S162, or NO in S163.

After executing the fail-safe process in S182, the ECU 300 turns on each of SMR-B51 and SMR-G61 in S181. As a result, the power path of the battery 100 is connected, and each of the SMR-B51 and the SMR-G61 is energized. Then, when the process of S181 is executed, the process of FIG. 4 ends, and the process is returned to the main routine.

FIG. 6 is a timing chart showing an example of each transition between the value of the counter C1 in the process of FIG. 4, the state of the IGSW500, and the state of the system main relay. The transition of each parameter shown in FIG. 6 is a transition when the determination condition is satisfied. In FIG. 6, the line L1 shows the transition of the value of the counter C1, the line L2 shows the transition of the state of the IGSW500, and the line L3 shows the transition of the state of the system main relays (SMR-B51, SMR-G61).

With reference to FIG. 4 and FIG. 6, when the user turns off the IGSW500 at timing t11 (line L2), it is determined to be YES in S11, and the system main relays (SMR-B51, SMR-G61) are turned off in S12. (Line L3), counting by the counter C1 is started by S13 to S15 (line L1).

After that, when the IGSW500 is turned on by the user at the timing t12 (line L2), it is determined to be YES in S14, and the success or failure of the determination condition is determined in S161 to S163. Then, when it is determined that the determination condition is satisfied in S161 to S163 (YES in all of S161 to S163), the determination of the presence or absence of an abnormality in S17 is executed. Then, when this determination is completed, the system main relays (SMR-B51, SMR-G61) are turned on at the timing t13 (line L3). More specifically, if it is determined that no sensor abnormality has occurred in S17, the system main relay is turned on in S181 without going through S182. On the other hand, if it is determined that a sensor abnormality has occurred in S17, the system main relay is turned on in S181 after the fail-safe process is executed in S182. The determination of the presence or absence of an abnormality in S17 is executed during the period from timing t12 to t13.

As described above, in the ECU 300 of the power storage system according to this embodiment, the temperatures of SMR-B51 and SMR-G61 are stabilized after the SMR-B51 and SMR-G61 are changed from the energized state to the non-energized state. When (for example, when YES is determined in S161 after the execution of S12 in the process of FIG. 4), the detected values (T1 and T2) of the temperature sensors 52 and 62 are acquired, and their temperature deviations (more specific) are acquired. Specifically, the presence or absence of an abnormality in the sensor is determined using the temperature difference | T1-T2 |) (S17 in FIG. 4). Even if the SMR-B51 and SMR-G61 provided in the power path of the battery 100 are energized and generate heat, the presence or absence of an abnormality in the sensor (S17 in FIG. 4) is determined by the SMR-B51 and SMR-G61. It is performed after each temperature becomes stable (that is, after each of SMR-B51 and SMR-G61 is in the state before heat generation). Therefore, the fluctuation of the temperature deviation caused by the difference in the heat generation characteristics (ease of heat generation) of SMR-B51 and SMR-G61 is suppressed, and the abnormality of the temperature sensors 52 and 62 can be detected with high accuracy. ..

[Embodiment 2]
In S161 of FIG. 4 in the first embodiment, it is estimated that the temperatures of SMR-B51 and SMR-G61 are stabilized by a method that does not use a temperature sensor. More specifically, in the first embodiment, the temperatures of SMR-B51 and SMR-G61 are stable when a predetermined time or more has elapsed since both SMR-B51 and SMR-G61 were de-energized. I presume that it was done. However, the method for determining whether or not the temperatures of SMR-B51 and SMR-G61 are stable is not limited to the method of the first embodiment.

Hereinafter, the power storage system according to the second embodiment of the present disclosure will be described with reference to FIGS. 7 and 8. The power storage system according to the second embodiment basically has a configuration similar to the power storage system according to the first embodiment. However, in the power storage system according to the second embodiment, the ECU 300 is configured to perform the process of FIG. 7 instead of the process of FIG. Since the second embodiment has many parts in common with the first embodiment, the differences will be mainly described, and the description of the common parts will be omitted.

FIG. 7 is a flowchart showing a processing procedure for detecting an abnormality in the temperature sensor executed by the ECU 300 of the power storage system according to the second embodiment of the present disclosure. Hereinafter, the differences from the processing of FIG. 4 will be mainly described.

With reference to FIG. 7, the ECU 300 determines whether or not the state of the vehicle 1 is READY-OFF in S21, and if YES in S21, the ECU 300 determines in S22 the system main relay (SMR-B51). , SMR-G61) is turned off. Since S21 and S22 in FIG. 7 are the same as S11 and S12 in FIG. 4, the description thereof will be omitted.

Subsequently, the ECU 300 determines the success or failure of the determination condition in S231 to S242. In the example of FIG. 7, it is a necessary and sufficient condition for the determination condition to be satisfied that YES is determined in all of S231, S232, and S242. Since S231 and S232 in FIG. 7 are the same as S162 and S163 in FIG. 4, the description thereof will be omitted.

If YES is determined in both S231 and S232, the ECU 300 acquires the detected values of the temperature sensors 52 and 62 in S241 and stores them in the memory 302. Subsequently, in S242, the ECU 300 uses the data saved in S241 to determine the amount of change in T1 (that is, the detected value of the temperature sensor 52) per unit time (hereinafter, also referred to as “dT1 / dt”) and T2. The amount of change per unit time (hereinafter, also referred to as "dT2 / dt") of (that is, the detection value of the temperature sensor 62) is calculated, and each of the calculated dT1 / dt and dT2 / dt has a predetermined threshold. Judge whether it is below the value. The threshold values for each of dT1 / dt and dT2 / dt are obtained in advance by, for example, an experiment and are stored in the memory 302. The threshold value used in S242 may be a fixed value or may be variable depending on the situation of the vehicle 1 and the like. Further, the threshold value for dT1 / dt and the threshold value for dT2 / dt may be the same or different from each other.

FIG. 8 is a diagram showing an example of each transition of T1 and T2. In FIG. 8, the line S1 shows the transition of T1 and the line S2 shows the transition of T2. With reference to FIG. 8, when the IGSW500 is turned off by the user at the timing t21 (that is, the state of the vehicle 1 becomes READY-OFF), each of the SMR-B51 and the SMR-G61 is de-energized. Be cooled. Then, as the temperature of SMR-B51 and SMR-G61 decreases, T1 (line S1) and T2 (line S2) decrease.

As time elapses from the timing t21, dT1 / dt (slope of line S1) and dT2 / dt (slope of line S2) become smaller. Since dT1 / dt and dT2 / dt indicate the degree of temperature decrease of SMR-B51 and SMR-G61, respectively, small dT1 / dt and dT2 / dt make it difficult for SMR-B51 and SMR-G61 to be cooled, respectively. It means that it has become. Then, at the timing t22, dT1 / dt and dT2 / dt become values close to 0. The fact that dT1 / dt and dT2 / dt are close to 0 means that T1 and T2 are stable (that is, T1 and T2 hardly change). If each of dT1 / dt and dT2 / dt is sufficiently small, it is considered that the temperatures of SMR-B51 and SMR-G61 are stable (see lines S1 and S2).

With reference to FIG. 7 again, when at least one of dT1 / dt and dT2 / dt exceeds a predetermined threshold value (NO in S242), at least one of SMR-B51 and SMR-G61 is sufficient. It is judged that the temperature is not low. While NO is determined in S242, the processes of S241 and S242 are repeated every control cycle. When the ECU 300 receives a signal indicating READY-ON from the IGSW500 while repeatedly executing the processes of S241 and S242, the ECU 300 stops the abnormality detection of the temperature sensor (process of FIG. 7) and turns off the system main relay. You may turn it on.

When it was determined that each of dT1 / dt and dT2 / dt was below a predetermined threshold value (YES in S242), both SMR-B51 and SMR-G61 became sufficiently low temperatures (and thus). , The judgment condition is satisfied). Then, in S251, the power of the ECU 300 is turned off, and the ECU 300 is stopped. The stopped state includes a power saving mode (sleep, etc.). In this embodiment, a sleep state is adopted as the stop state.

Subsequently, in S26, it is determined whether or not the state of the vehicle 1 is READY-ON. More specifically, the ECU 300 determines that the state of the vehicle 1 is READY-OFF (NO in S26) while the ECU 300 does not receive the signal indicating READY-ON from the IGSW500, and the signal indicating READY-ON from the IGSW500. Is received, it is determined that the state of the vehicle 1 is READY-ON (YES in S26).

The ECU 300 maintains the above sleep state while it is determined to be NO in S26. On the other hand, if YES is determined in S26, the ECU 300 is activated (that is, wakes up from the sleep state) in S252. As a result, the ECU 300 is in a normal operating state.

After the processing of S252, the determination of the presence or absence of an abnormality is executed in S27. When it is determined in S27 that no sensor abnormality has occurred (NO in S27), the system main relay is turned on in S281 without going through S282. On the other hand, if it is determined that a sensor abnormality has occurred in S27 (YES in S27), the fail-safe process is executed in S282, and then the system main relay is turned on in S281. Since S27, S281, and S282 in FIG. 7 are the same as S17, S181, and S182 in FIG. 4, the description thereof will be omitted.

As described above, in the power storage system according to the second embodiment, when the temperatures of SMR-B51 and SMR-G61 become stable after the SMR-B51 and SMR-G61 are changed from the energized state to the non-energized state (for example,). , When it is determined to be YES in S242 after the execution of S22 in the process of FIG. 7, the detected values (T1 and T2) of the temperature sensors 52 and 62 are acquired, and their temperature deviations (more specifically, more specifically). , Temperature difference | T1-T2 |) is used to determine the presence or absence of an abnormality in the sensor (S27 in FIG. 7). Therefore, even in the power storage system according to the second embodiment, the fluctuation of the temperature deviation caused by the difference in the heat generation characteristics of the SMR-B51 and the SMR-G61 is suppressed, and the abnormality of the temperature sensors 52 and 62 is detected with high accuracy. Will be possible.

[Embodiment 3]
Hereinafter, the power storage system according to the third embodiment of the present disclosure will be described with reference to FIG. The power storage system according to the third embodiment basically has a configuration similar to the power storage system according to the second embodiment. However, in the power storage system according to the third embodiment, the ECU 300 is configured to perform the process of FIG. 9 instead of the process of FIG. 7. Since the third embodiment has many parts in common with the second embodiment, the differences will be mainly described, and the description of the common parts will be omitted.

FIG. 9 is a flowchart showing a processing procedure for detecting an abnormality in the temperature sensor executed by the ECU 300 of the power storage system according to the third embodiment of the present disclosure. Hereinafter, the differences from the processing of FIG. 7 will be mainly described.

In the process of FIG. 9, similarly to the process of FIG. 7, the processes of S241 and S242 are repeatedly performed while it is determined to be NO in S242. However, in the process of FIG. 9, the processes of S241 and S242 are executed every time a predetermined start condition is satisfied, not every control cycle.

If it is determined to be NO in S242 with reference to FIG. 9, the power of the ECU 300 is turned off after the predetermined start condition is set in the ECU 300 in S243. As a result, the ECU 300 goes into a stopped state (for example, a sleep state). By setting the start condition in the ECU 300, the ECU 300 is started when the start condition is satisfied. The start condition can be set arbitrarily, but in this embodiment, the start condition is satisfied after a predetermined time has elapsed from the present time (when the start condition is set). The predetermined time may be a fixed value or a variable value. For example, the predetermined time may be shortened as the number of times that NO is determined in S242 (and by extension, the number of times of processing in S243) increases.

After the processing of S243, it is determined in S244 whether or not the start condition is satisfied. While the start condition is not satisfied (NO in S244), the ECU 300 maintains the above-mentioned stopped state (for example, sleep state). Then, when it is determined that the start condition is satisfied (YES in S244) (that is, when the predetermined time elapses), the ECU 300 is started in S245 and the processes of S241 and S242 are executed.

Also in the power storage system according to the third embodiment, the fluctuation of the temperature deviation caused by the difference in the heat generation characteristics of the SMR-B51 and the SMR-G61 can be suppressed, and the abnormality of the temperature sensors 52 and 62 can be detected with high accuracy. It will be possible. Further, in the process of FIG. 9, since the start-up time of the ECU 300 is shortened, the power consumption can be reduced.

[Other embodiments]
In the process of FIG. 4, the ECU 300 may be put into a stopped state (for example, a sleep state) while waiting until the state of the vehicle 1 becomes READY-ON (a period determined to be NO in S14).

In each of the above embodiments, it is determined that the sensor abnormality has occurred even if it is determined that the temperature deviation is large (YES in S17 or S27) in one trip. However, the present invention is not limited to this, and when it is determined that the temperature deviation is large in succession in a plurality of trips, it may be determined that the sensor abnormality has occurred. It should be noted that one trip is from READY-ON to READY-OFF.

In each of the above embodiments, the ECU 300 executes the fail-safe process. However, the present invention is not limited to this, and the ECU 300 may perform up to the abnormality detection of the temperature sensors 52 and 62, and the subsequent processing may be left to the user.

In the above embodiment, a blower is adopted as the cooling device 240. However, the present invention is not limited to this, and instead of the blower device, another cooling device (for example, a water-cooled cooling system or a refrigerant cooling system cooling device) may be adopted.

In each of the above embodiments, system main relays (SMR-B51 and SMR-G61) are adopted as the first component and the second component. However, the first component and the second component are not limited to the system main relay, and may be other components provided in the power path of the power storage device. For example, each of the first component and the second component may be a charging relay provided in the charging path of the power storage device. Further, as another example of the first component and the second component, an S / P, a fuse box, and a PN connector can be mentioned.

In each of the above embodiments, the determination condition is appropriately as long as the temperature of each of the first component and the second component is stabilized after the first component and the second component are changed from the energized state to the non-energized state. It can be changed. For example, in the process of FIG. 4, at least one of S162 and S163 may be omitted. Further, in the processing of FIGS. 7 and 9, at least one of S231 and S232 may be omitted.

The configuration of the vehicle 1 to which the power storage system according to each of the above embodiments is applied can be appropriately changed. Further, the configuration of the battery 100 can be changed as appropriate. For example, a cell battery may be adopted instead of the assembled battery.

The embodiments disclosed this time should be considered to be exemplary and not restrictive in all respects. The scope of the present invention is shown by the scope of claims rather than the description of the embodiments described above, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

1 vehicle, 2 battery pack, 11, 12 MG, 20 engine, 30 drive wheels, 31 power splitting device, 32 drive shaft, 40 PCU, 50, 60 JB, 51 SMR-B, 52 temperature sensor, 53 charging relay, 61 SMR-G, 62 temperature sensor, 63 charging relay, 100 battery, 210 voltage sensor, 220 current sensor, 230 temperature sensor, 240 cooling device, 300 ECU, 301 CPU, 302 memory, 400 notification device, 500 IGSW.

Claims (3)

Power storage device and
The first component and the second component provided in the power path of the power storage device, and
A first temperature sensor that detects the temperature of the first component,
A second temperature sensor that detects the temperature of the second component,
Electronic control unit and
Equipped with
The electronic control unit satisfies a predetermined condition including that the temperatures of the first component and the second component are stabilized after the first component and the second component are de-energized from the energized state. It is configured to be in a stopped state when
When the electronic control unit returns from the stopped state, the first detected temperature, which is the temperature of the first component detected by the first temperature sensor, and the second component detected by the second temperature sensor. An abnormality occurs in at least one of the first temperature sensor and the second temperature sensor by acquiring the second detection temperature, which is the temperature, and using the temperature deviation between the first detection temperature and the second detection temperature. A power storage system that determines whether or not it is installed. Power storage device and
The first component and the second component provided in the power path of the power storage device, and
A first temperature sensor that detects the temperature of the first component,
A second temperature sensor that detects the temperature of the second component,
Electronic control unit and
Equipped with
The electronic control unit is configured to be in a stopped state by setting a start condition after the first component and the second component are de-energized from the energized state.
The electronic control unit is started when the start condition is satisfied, and determines whether or not a predetermined condition including that the temperatures of the first component and the second component are stable is satisfied. When the predetermined condition is satisfied , the first detected temperature, which is the temperature of the first component detected by the first temperature sensor, and the second temperature, which is the temperature of the second component detected by the second temperature sensor. The detected temperature is acquired, and the temperature deviation between the first detected temperature and the second detected temperature is used to determine whether or not an abnormality has occurred in at least one of the first temperature sensor and the second temperature sensor. Judgment, power storage system. A cooling device for cooling the power storage device, the first component, and the second component is further provided.
The electronic control unit has dT1 / dt, which is the amount of change in the detected value of the first temperature sensor per unit time, and dT2 / dt, which is the amount of change in the detected value of the second temperature sensor per unit time. Configured to calculate
The electronic control unit is used when each of the dT1 / dt and the dT2 / dt becomes equal to or lower than a predetermined threshold value after the first component and the second component are de-energized from the energized state. The power storage system according to claim 1 or 2, wherein it is determined that the temperatures of the first component and the second component are stable.

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