JP6589368B2 - Power supply apparatus and diagnostic method for diagnosing abnormality of power supply apparatus - Google Patents

Description

  The present invention relates to a power supply device and a diagnosis method for diagnosing an abnormality of the power supply device.

  A power storage device inspection and maintenance method is disclosed in Patent Document 1. The power storage device to be inspected includes a battery module including a battery monitoring unit that monitors a plurality of batteries connected in series, an assembled battery unit including battery modules connected in series, a service disconnect including a fuse, A switch circuit that turns on or off the discharge path, and a battery management device that performs mutual communication with the battery monitoring unit and control of the switch circuit are provided. And in the inspection and maintenance method, the current is detected from the current sensor at the time of charging and discharging, and when the battery management unit determines that charging and discharging cannot be performed in the assembled battery unit, the resistance between the contacts of the switch circuit is measured, Detects whether the switch circuit is welded.

JP 2013-73897 A

However, in the above inspection and maintenance method, the assumption for detecting the welding of the switch circuit, actually flowing current by charging and discharging of the battery, it is determined whether it is charged and discharged in the assembled battery unit Yes. For this reason, there is a possibility that the battery capacity varies due to the power consumption when detecting the welding of the switch circuit, or that the battery capacity varies.

  The problem to be solved by the present invention is to provide a power supply apparatus and a power supply apparatus diagnosis method capable of diagnosing the state of the power supply apparatus without changing the variation in battery capacity.

  The present invention provides a plurality of battery bodies having a secondary battery, a positive switch connected to the positive electrode side of the secondary battery, and a negative switch connected to the negative electrode side of the secondary battery in parallel as a battery group. In the connected state, each insulation resistance of the battery group is detected, a switching command for switching on and off the positive side switch and the negative side switch is output, and the positive side is determined based on the detected value of the insulation resistance and the switching command. The problem is solved by diagnosing an abnormality in at least one of the switch and the negative switch.

  Since the present invention diagnoses whether the positive switch or the negative switch is operating normally with respect to the switching command from the insulation resistance of the battery group, the battery is charged or discharged to the load. In this state, switch abnormality can be diagnosed. As a result, since the present invention does not change the battery capacity when diagnosing the state of the power supply device, the state of the power supply device can be diagnosed without increasing the variation in battery capacity.

FIG. 1 is a block diagram of a power supply device according to this embodiment. FIG. 2 is a diagram illustrating a control flow when diagnosing the positive-side relay. FIG. 3 is a diagram showing a control flow of step S4 of FIG. FIG. 4 is a diagram illustrating a control flow when diagnosing the negative-side relay.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of a power supply apparatus 100 according to an embodiment of the present invention.

The power supply apparatus 100 according to the present embodiment includes a battery group 10 and a controller 20. The power supply device 100 is a power supply that supplies power to the load 30. In addition, the power supply device 100 can charge the battery B _n included in the battery body M _n with the electric power from the load 30. The power supply device is connected to the load 30.

  The battery group 10 has n battery bodies M. The n battery bodies M are connected in parallel. The positive electrodes of the n battery bodies M are connected to the load 30. The negative electrodes of the n battery bodies M are connected to the ground (GND). Note that n is an integer of 2 or more.

Cell body _{M n} includes a relay Ra _n, and the relay Rb _n, and the battery _{B n,} and an insulation resistance detection circuit IR _n. The n battery bodies M are connected in parallel in the power supply device 100. n represents the number of battery bodies incorporated in the power supply apparatus. As shown in FIG. 1, the nth battery body M in the order of the _first battery body M ₁ and the second battery body M _2. Up to _n battery bodies are connected. The n battery bodies M can be removed from the power supply device 100. For example, from a state in which n pieces of batteries body M is connected, it can be detached second battery body M _2. The power supply device 100 is configured such that power can be supplied from the other battery bodies (M ₁ , M ₃ , M _n ) with the second battery body M ₂ removed. Further, in the second place of the battery body M ₂ removed, the other battery body M may be connected to the second position of the cell body M _2. At this time, the other newly connected battery body M is not necessarily an unused battery body, and may be a battery body after use. Thereby, the power supply apparatus 100 can adjust battery capacity flexibly according to the scale of the load 30.

Relay Ra _n are switches for conducting and interrupting the circuit of the positive side of battery B _n. Relay Ra _n is connected to the positive electrode of battery _{B n.} When the relay Ra _n is in the on state, the positive electrode of the battery _{B n} are electrically connected to the load 30, and other relays _{Ra 1 ~Ra n-1,} when the relay Ra _n is in the off state, the battery _{B n} The positive electrode is disconnected from the load 30 and the other relays Ra _{1 to} Ran _-1 .

The relay Rb _n is a switch that turns on and off the negative circuit of the battery B _n . Relay Rb _n is connected to the negative electrode of battery _{B n.} When the relay Rb _n is in the on state, the negative electrode of the battery B _n is electrically connected to the load 30 and the other relays Rb _{1 to} Rb _n−1, and when the relay Rb _n is in the off state, the battery B _n The negative electrode is disconnected from the load 30 and the other relays Rb _{1 to} Rb _n−1 .

The battery _Bn is a series body of batteries in which a plurality of secondary batteries are connected in series. For example, a lithium ion battery is used as the secondary battery.

Insulation resistance detecting circuit IR _n is a circuit for detecting the insulation resistance of the battery body M _n. The insulation resistance detection circuit IR _n, the insulation resistance of the battery _{B n} may be detected. Insulation resistance detecting circuit IR _n includes a connection line connecting between the battery _{B n} relay Rb _n, is connected between the ground (GND). That is, the insulation resistance detection circuit IR _n is connected between the strong electric power of the battery body M _n and the ground of the low electric power. Then, the insulation resistance detection circuit IR _n detects the insulation resistance in the battery body M _n including the insulation resistance of the battery B _n by measuring the impedance between the strong electric current and the low electric current. Insulation resistance detecting circuit IR _n contained battery _{B n,} which detects the insulation resistance from the relay Ra _n to relay Rn _b. Insulation resistance detecting circuit IR _n, by detecting the voltage, and detects the insulation resistance.

  For example, the insulation resistance detection circuit IRn detects the impedance between the strong electric current and the low electric current by outputting a pulse, which is a voltage signal having a predetermined amplitude, to the connection point of the battery body Mn with the strong electric current. It can be detected from the voltage change. In other words, the voltage amplitude at the connection point when a pulsed voltage is applied to the connection point varies depending on the impedance between the strong and weak electricity, and the voltage amplitude at the connection point becomes smaller as the impedance is lower. The insulation resistance in the battery body Mn can be detected by measuring the amplitude. Since such an insulation resistance detection method is a well-known method already known, as described in, for example, Japanese Patent Application Laid-Open No. 2003-250201 and Japanese Patent Application Laid-Open No. 2004-53365, detailed description thereof is omitted. .

Note that the configuration of the battery body _{M 1} ~ cell body _{M n-1} has the same configuration as the battery body _{M n,} the description thereof is omitted.

  The controller 20 is a controller for controlling the n battery bodies M, and includes a CPU, a RAM, and the like. In addition, the controller 20 includes a battery management unit 21, a relay control unit 22, and an abnormality diagnosis unit 23 as functional blocks when controlling the battery body M.

  The battery management unit 21 controls the output and input of the battery body M while managing the state of each battery B included in the n battery bodies M. The battery management unit 21 manages the state of the battery B using a detection value (voltage of the battery B) of a sensor (not shown) connected to the battery body M. The battery management unit 21 controls charging and discharging of the battery B so that each battery B does not become overcharged or overdischarged. In addition, when the battery B is likely to be overcharged or overdischarged, the battery management unit 21 sends a control signal for turning off the relays Ra and Rb connected to the target battery B to the relay control unit 22. Output to. The relay control unit outputs a switching signal so as to turn off the relays Ra and Rb specified by the control signal. Thereby, the battery B which is likely to be overcharged or overdischarged is disconnected, and safety can be ensured.

  The relay control unit 22 switches the n relays Ra on and off, and the n relays Rb on and off, respectively. The relay control unit 22 outputs switching signals for switching on and off to the n relays Ra and the n relays Rb, respectively, and switches the states of the relays Ra and Rb. The relay control unit 22 turns on all the relays Ra and Rb when supplying the power of the n battery bodies M to the load 30. Further, when disconnecting some of the n battery bodies M, the relay control unit 22 turns off the relays Ra and Rb of the battery body M to be disconnected, and the batteries that are not to be disconnected. The relays Ra and Rb of the body M are turned on. Further, the relay control unit 22 transmits a switching signal for diagnosing the abnormality of the relays Ra and Rb and the abnormality of the battery B to the relays Ra and Rb according to the control command from the abnormality diagnosis unit 23.

  The abnormality diagnosis unit 23 diagnoses abnormality of n relays Ra, abnormality of n relays Rb, and ground faults of n batteries B, respectively. The abnormality diagnosis unit 23 receives the resistance value (detection value) of the insulation resistance detected by the n insulation resistance detection circuits IR. The abnormality diagnosis unit 23 diagnoses the abnormality of the relays Ra and Rb and the ground fault of the battery B (decrease in insulation resistance) by using the switching function of the relays Ra and Rb by the relay control unit 22. Then, the abnormality diagnosis unit 23 diagnoses the abnormality of the relays Ra and Rb and the ground fault of the battery B based on the input resistance value of the insulation resistance and the switching signal output from the relay control unit 22. Details of the diagnostic function by the abnormality diagnosis unit 23 will be described later.

  Incidentally, the relays Ra and Rb switch between conduction and interruption of a large current under a high voltage. For this reason, the contacts of the relays Ra and Rb may be fixed. For example, when the relays Ra and Rb are fixed to the ON side when the overcharged or overdischarged battery body M is disconnected, the relays Ra and Rb cannot be turned off, and the current of the battery body M Can not be cut off. Therefore, the power supply apparatus 100 according to the present embodiment diagnoses the abnormality of the relays Ra and Rb in the following manner.

The diagnosis control for diagnosing the abnormality of the relays Ra and Rb and the detection control for detecting the decrease in the insulation resistance of the battery B will be described with reference to FIGS. FIG. 2 is a flowchart of diagnostic control when diagnosing the positive-side relay Ra. FIG. 3 is a flowchart of diagnostic control when diagnosing an abnormality of the _first relay Ra ₁ . FIG. 4 is a flowchart of diagnostic control when diagnosing the negative relay Rb.

  As an initial condition, the relay control unit 22 turns off all the relays Rb on the negative side.

In step S1, the relay control unit 22 outputs a switching signal for turning off the relay Ra to all the relays Ra on the plus side. The abnormality diagnosis unit 23 detects the insulation resistance of each of the battery bodies M _{1 to} M _n by the insulation resistance detection circuits IR _{1 to} IR _n when outputting an off signal to all the relays Ra. Then, abnormality diagnosis unit 23 diagnoses the battery _B 1 .about.B _n ground and the on-fixation of the relay _Ra 1 to Ra _n of the (On sticking).

Among the detection values of the insulation resistance detection circuits IR _{1 to} IR _n (resistance values of the insulation resistances of the battery bodies M _{1 to} M _n ), one detection value is a normal value (a predetermined ground fault occurs. If the resistance value is lower than the resistance value of the battery B, the abnormality diagnosis unit 23 determines in step S2 that the insulation resistance of the battery B has decreased. The battery B whose insulation resistance is lowered is the battery B included in the battery body M having an insulation resistance lower than a normal value. The normal value indicates the insulation resistance of the battery body M when the battery B is in a normal state, and is a preset value. When the insulation resistance of the battery B is lowered, there is a possibility that a ground fault has occurred in the battery B. Therefore, the abnormality diagnosis unit 23 outputs a command to the effect that the abnormality has occurred in the battery B to the battery management unit 21 and ends the diagnosis control flow.

When two or more detection values are lower than normal values among the detection values of the insulation resistance detection circuits IR _{1 to} IR _n (resistance values of the insulation resistances of the battery bodies M _{1 to} M _n ), the process proceeds to step S3. Thus, the abnormality diagnosis unit 23 determines that the positive relay Ra is stuck on. The relay Ra in which the on-fixation has occurred is a relay Ra included in the battery body M having an insulation resistance lower than a normal value. The abnormality diagnosing unit 23 ends the diagnosis control flow after diagnosing the on-fixation of the relay Ra.

If all the detection values of the insulation resistance detection circuits IR _{1 to} IR _n are equal to or higher than the normal value, the abnormality diagnosis unit 23 diagnoses the first relay Ra ₁ to be fixed in step S4.

The control flow of step S4 will be described using FIG. FIG. 3 shows a sub-control flow of step S4. First, the abnormality diagnosing unit 23 diagnoses whether or not the on-fixation has occurred in the relay Ra ₁ by the control flow from step S21 to step S27.

In step S21, the relay control unit 22 outputs a switching signal (also referred to as an ON command) for turning on the relay Ra to the _second relay Ra ₂ and a switching signal (OFF) for turning off the relay Ra. also referred) to the relay _Ra 3 to Ra _n from the third first relay Ra ₁ and to the n-th and the command.

In step S22, the abnormality diagnostic section 23, the detection value of the first insulation resistance detection circuit IR ₁ is judged whether or not lower than the detection value of the insulation resistance detection circuit IR ₁ before the output of the ON command.

Detection values of the insulation resistance detection circuit IR ₁ is lower than the detection value of the insulation resistance detection circuit IR ₁ before output on command, at step S23, the abnormality diagnostic section 23, the first relay Ra ₁ It is determined that on-sticking has occurred. When the first relay Ra ₁ is stuck on, the first relay Ra ₁ is electrically connected to the second relay Ra ₂ that is turned on by the switching signal. closed loop between the first cell member M ₁ and the second battery body M ₂ is formed. Therefore, when the ON command is output to the _second relay Ra2, the detection value of the _first insulation resistance detection circuit IR1 is lower than the detection value before the output of the ON command.

That is, when both of the relay Ra ₁ and the relay Ra ₂ are turned on, it is electrically connected in series with the battery body M ₁ (battery B ₁ ) and the battery body M ₂ (battery B ₂ ). the insulation resistance between the ground is in a state of insulation resistance and are connected in parallel between the insulation resistance and the battery body M ₂ and ground between the battery body M ₁ and the ground. Therefore, when the relay Ra ₁ is not stuck on (when the relay Ra ₁ is off), the detection value of the insulation resistance detection circuit IR ₁ does not change when the relay Ra ₂ is turned on. When the relay Ra ₁ is stuck on (when the relay Ra ₁ is on), the detection value of the insulation resistance detection circuit IR1 decreases when the relay Ra2 is turned on.
After diagnosing the on-fixation of the first relay Ra, the abnormality diagnosis unit 23 ends the diagnosis control flow.

Detection values of the insulation resistance detection circuit IR ₁ is, if it is greater than the detection value of the output before the insulation resistance detection circuit IR ₁ ON command, check the third relay Ra _3, 1-th relay Ra ₁ It is determined again whether or not on-fixing has occurred.

In the control flow of steps S21 to S23, if the second relay Ra ₂ is stuck off, even if an on command is output to the relay Ra ₂ , the state of the _first relay Ra ₁ is affected. no, a closed loop is not formed between the first cell member M ₁ and the second battery body M _2. For this reason, the abnormality diagnosis unit 23 may not be able to diagnose the on-fixation of the _first relay Ra ₁ . Therefore, in this embodiment, at step S3, the second relay Ra ₂ except other positive side of the relay is turned on, is performed reassessment of the on-fixation relay Ra _1.

In step S24, the relay control unit 22 outputs an ON command to the third relay Ra _3, and outputs a switching signal for turning off the relay Ra to the _first relay Ra ₁ and the second relay Ra ₂ . and output to the relay _Ra 4 to Ra _n from the fourth to n-th.

At step S25, the abnormality diagnostic section 23, the detection value of the first insulation resistance detection circuit IR ₁ is judged whether or not lower than the detection value of the insulation resistance detection circuit IR ₁ before the output of the ON command.

Detection values of the insulation resistance detection circuit IR ₁ is lower than the detection value of the insulation resistance detection circuit IR ₁ before output on command, at step S26, the abnormality diagnostic section 23, the first relay Ra ₁ It is determined that on-sticking has occurred.

On the other hand, the detection value of the insulation resistance detection circuit IR ₁ is, if it is greater than the detection value of the insulation resistance detection circuit IR ₁ before output on command, at step S27, the abnormality diagnostic section 23, the first relay It is determined that Ra ₁ is not stuck on.

Next, the abnormality diagnosis unit 23 diagnoses whether or not the relay Ra ₁ is stuck off by the control flow from step S28 to step S34.

In step S28, the relay control unit 22 outputs an ON command to the first relay Ra ₁ and the third relay Ra _3, and outputs an OFF command to the second relay Ra ₂ and the fourth to nth relays. and outputs it to Ra ₄ ~Ra _n.

In step S29, the abnormality diagnostic section 23, the detection value of the first insulation resistance detection circuit IR ₁ is judged whether or not lower than the detection value of the insulation resistance detection circuit IR ₁ before the output of the ON command.

Detection values of the insulation resistance detection circuit IR ₁ is, if it is greater than the detection value of the insulation resistance detection circuit IR ₁ before output on command, at step S30, the abnormality diagnostic section 23, the first relay Ra ₁ It is determined that the occurrence of off-fixation occurs. When the first relay Ra ₁ is stuck off, even if the on command is output to the _first relay Ra ₁ and the third relay Ra ₃ , the first relay Ra ₁ Since the third relay Ra ₃ is not electrically connected, a closed loop is not formed between the _first battery body M ₁ and the third battery body M ₃ . Therefore, even if the ON command is output to the _first relay Ra ₁ and the third relay Ra ₃ , the detection value of the _first insulation resistance detection circuit IR ₁ is compared with the detection value before the ON command is output. It does not decline. After diagnosing the first relay Ra being stuck off, the abnormality diagnosis unit 23 ends the diagnosis control flow.

Detection values of the insulation resistance detection circuit IR ₁ is lower than the detection value of the insulation resistance detection circuit IR ₁ before output on command, at step S31, the abnormality diagnostic section 23, first the relay Ra ₁ The second relay Ra ₂ is turned on, and it is determined again whether or not the _first relay Ra ₁ is stuck off. In the present embodiment, when the second relay Ra ₂ is stuck on, the control flow from step S28 to step S30 may not be able to accurately determine whether the relay Ra ₁ is stuck off. The second relay Ra ₂ is turned on to re-diagnose the relay Ra ₁ from being stuck off.

In step S31, relay control unit 22, the ON command first relay Ra _1, and outputs a second relay Ra _2, the output to the relay _Ra 3 to Ra _n from the third off command through n To do.

In step S32, the abnormality diagnostic section 23, the detection value of the first insulation resistance detection circuit IR ₁ is judged whether or not lower than the detection value of the insulation resistance detection circuit IR ₁ before the output of the ON command.

Detection values of the insulation resistance detection circuit IR ₁ is, if it is greater than the detection value of the insulation resistance detection circuit IR ₁ before output on command, at step S33, the abnormality diagnostic section 23, the first relay Ra ₁ It is determined that the occurrence of off-fixation occurs.

Detection values of the insulation resistance detection circuit IR ₁ is lower than the detection value of the insulation resistance detection circuit IR ₁ before output on command, at step S34, the abnormality diagnostic section 23, the first relay Ra ₁ It is determined that off sticking has not occurred. In step S35, the abnormality diagnosis unit 23 determines that the _first relay Ra ₁ is normal. As a result, it is determined that the state of the _first relay Ra ₁ is normal, and the control flow in step S4 ends.

As shown in FIG. 2, at step S5, relay control unit 22 outputs an ON command to the first relay Ra _1, each relay _Ra 2 to Ra _n of the OFF command from the second to n-th output To do. In step S6, the abnormality diagnosis unit 23, the detection value of the insulation resistance detection circuit IR ₂ ～IR _n from the second to the n th, insulation resistance detection circuit IR from the second prior output on command through n whether ₂ ～IR or _n lower than the detection value of each is determined.

If any one of the detection values of the second to nth insulation resistance detection circuits IR _{2 to} IR _n is lower than the detection value before the output of the ON command, an abnormality is detected in step S7. The diagnosis unit 23 determines that the positive relay Ra is stuck on. The relay Ra in which the on-fixation has occurred is the relay Ra included in the battery body M having an insulation resistance lower than the detection value before the output of the on command. The abnormality diagnosing unit 23 ends the diagnosis control flow after diagnosing the on-fixation of the relay Ra.

_If the detection values of the second to nth insulation resistance detection circuits IR _{2 to} IR _n are equal to or higher than the detection value before the output of the ON command, the abnormality diagnosis unit 23 starts from the second in step S8. It determines that on-fixation to the n-th relay _Ra 2 to Ra _n is not generated.

The diagnosis control of the step S4, the state of the relay Ra ₁ is determined to be normal. When all of the positive side relays Ra 1 to _n and all of the negative side relays Rb 1 to _n are in an OFF state, and outputs an ON command to the _first relay Ra ₁ , the second to nth relays Ra ₂ of to Ra _n, if the on-fixation occurs in any one of the relay Ra is between the first relay Ra ₁ and the on-fixation of the relay Ra is electrically conductive, the insulation resistance detection circuit The IR detection value is lower than the detection value before the output of the ON command. Then, abnormality diagnosis unit 23, by specifying reduced insulation resistance detection circuit IR insulation resistance, or of the n-th relay Ra ₂ to Ra _n from the second, on-fixation in which the relay Ra is occurring Can be diagnosed.

On the other hand, between the second when the n-th all relays _Ra 2 to Ra _n are the on-fixation does not occur, the first relay Ra ₁ and from the second and n-th relay _Ra 2 to Ra _n Is in a blocked state, the detection values of the insulation resistance detection circuits IR _{1 to} IR _n are not lowered from the detection values before the output of the ON command. Therefore, the abnormality diagnosis unit 23 may diagnose that the on-fixation from the second to n-th relay Ra ₂ to Ra _n is not generated.

After the control in step S8, in step S9, the relay control unit 22 sets the relay Ra to be the output target of the ON command to the second relay Ra ₂ (corresponding to p = 2 shown in FIG. 2). P is an integer from 2 to n). In step S10, relay control unit 22 outputs an ON command to the first relay Ra ₁ and the p-th relay Ra _p, the OFF command to the first relay Ra ₁ and the p-th relay Ra _p other relay Ra Output each.

In step S11, the abnormality diagnostic section 23, the detection value of the p-th insulation resistance detection circuit IR _p is whether or not lower than the detection value of the p-th insulation resistance detection circuit IR _p before output on command judge. Detection values of the p-th insulation resistance detection circuit IR _p is, when the ON is not lower than the detection value of the previous output of the command, at step S12, the abnormality diagnostic section 23, the p-th relay Ra _p Off It is determined that sticking has occurred. Abnormality diagnosis unit 23, after diagnosing the off-fixation of the p-th relay Ra _p, and terminates the control flow of the diagnosis.

Detection values of the p-th insulation resistance detection circuit IR _p is, when lower than the detection value of the previous output of the ON command, at step S13, the abnormality diagnostic section 23 is turned off affixed to p-th relay Ra _p It is determined that it has not occurred. In step S14, the abnormality diagnosis unit 23 determines whether p has reached n. If p is less than n, in step S15, the controller 20 executes the control flow in step S10 while incrementing p. Then, the controller 20 repeatedly executes the control flow from step S10 to step S15 until p reaches n, thereby diagnosing off-fixation from the second to the nth.

If p is equal to n, in step S16, the controller 20 determines that all of the positive side relays _Ra1 to Ra are normal, and ends the control flow for diagnosis of the positive side relay Ra.

From the control flow up to step S8, it is determined that the state of the relay Ra ₁ is normal and that the relays Ra 2 to _n are not stuck on. When all relays Ra 1 to _n on the positive side and all relays Rb 1 to _n on the negative side are in an off state, an on command is output to the _first relay Ra ₁ and the p th relay Ra _p. when the off-fixation relay Ra _p of has occurred, first between the relay Ra _p relay Ra ₁ and off-fixation is electrically disconnected, the insulation resistance detection circuit IR _1, IR _p detection of The value does not fall below the detected value before the output of the on command. Accordingly, the abnormality diagnosis section 23, that off-fixation to p-th relay Ra _p is generated, can be diagnosed.

On the other hand, when the off-fixation to p-th relay Ra _p does not occur, between the first relay Ra ₁ and the p-th relay Ra _p is electrically conductive, the insulation resistance detection circuit IR _1, The detected value of IR _p is lower than the detected value before the output of the on command.

Accordingly, the abnormality diagnosis section 23, that off-fixation to p-th relay Ra _p is not generated, can be diagnosed. Further, the p-th relay Ra _p to output an ON command, the second to n-th by switching in the order, the abnormality diagnosis unit 23 may diagnose off-fixation of the relay Ra _{2- through n} of the second to n-th .

  When it is diagnosed that all the positive side relays Ra are normal, the abnormality diagnosing unit 23 diagnoses an abnormality of the negative side relay Rb by executing the control flow shown in FIG. As an initial condition when diagnosing the negative relay Rb, the relay control unit 22 turns off all the positive relays Rb.

Since the control flow from step S41 to step S48 is the same as the control flow from step S1 to step S8, description thereof is omitted. Further, the control flow in step S44 (diagnosis control of the _first negative relay Rb1) is the same as the control flow shown in FIG. However, the relay that outputs the switching signal and the relay to be diagnosed are not on the plus side but on the minus side.

After the control in step S48, the abnormality diagnosis unit 23 diagnoses the off-fixation of the negative relay Rb. In step S49, the relay control unit 22 outputs an ON command to all the negative relays Rb1 to _Rbn .

  In the diagnostic control of the on-fixation of the plus side relay Ra (corresponding to the control flow of steps S10 to S15 shown in FIG. 2), it is not determined that the minus side relay Rb is normal. From the first to the nth, the relay Ra is turned on one by one. Thereby, it is possible to prevent electrical conduction between the positive-side relay Ra that is turned on and the negative-side relay Rb that is on-fixed.

  On the other hand, in the diagnostic control of the on-fixation of the negative side relay Ra, since it is determined that the positive side relay Ra is normal, all the negative side relays Ra are turned off and all the negative side relays Ra are turned off. Even if the side relay Rb is turned on, the plus side relay Ra and the minus side relay Rb do not conduct. That is, since it is not necessary to turn on the relays Rb one by one from the second to the nth, the control flow is simplified and the calculation load on the controller 20 can be reduced.

At step S50, the abnormality diagnostic section 23, the detection value of the n-th insulation resistance detection circuit _{IR 2- through n} from the second is, n-th of the insulation resistance detection circuit from the second prior output on command _{IR 2- through n} It is determined whether or not the detected value has decreased. If any one of the second to nth insulation resistances is not lower than the insulation resistance before the output of the ON command, in step S51, the abnormality diagnosis unit 23 determines that the relay Rb It is determined that off sticking has occurred. The relay Rb in which the OFF sticking occurs is the relay Rb included in the battery body M having an insulation resistance lower than the detected value before the output of the ON command. The abnormality diagnosis unit 23 ends the diagnosis control flow after diagnosing the relay Rb being stuck off.

On the other hand, _if the detection values of the second to n-th insulation resistance detection circuits IR _{2 to} IR _n are equal to or greater than the detection value before the output of the on command, the abnormality diagnosis unit 23 determines that 2 It is determined that off-sticking has not occurred in the n th to n th relays Rb _{2 to} Rb _n . In step S53, the controller 20 determines that all the negative-side relays Rb 1 to _n are normal, and ends the control flow for diagnosis of the negative-side relay Rb.

  When the controller 20 detects a decrease in the insulation resistance of the battery B by the control flow described above, the controller 20 controls the relays Ra and Rb so as to disconnect the battery B whose insulation resistance has decreased from the other battery B. Moreover, the controller 20 ensures the safety | security of the battery B by fail safe control, when the adhesion of relay Ra, Rb is detected by said control flow.

  As described above, in this embodiment, each insulation resistance of the battery group 10 in which the battery bodies having the battery B, the relay Ra, and the relay Rb are connected in parallel is detected, and the relays Ra and Rb are turned on and off. A switching command for switching is output, and an abnormality of at least one of the relays Ra and Rb is diagnosed based on the detected value of the insulation resistance and the switching command. Thereby, since the abnormality of the switch can be diagnosed in a state where the battery is not charged or discharged with respect to the load, the present invention can diagnose the state of the power supply apparatus without changing the variation in the battery capacity.

  In the present embodiment, in a state where all the relays Ra and Rb are turned off, one of the plurality of relays Ra or one of the plurality of relays Rb is turned on. Outputs a command. When the ON command is output to the relay Ra, if the detected value of the insulation resistance is lower than the insulation resistance value before the ON command is output, the relay Ra other than the relay Ra from which the ON command is output is fixed to the relay Ra. Diagnose that has occurred. Further, when the ON command is output to the relay Rb, if the detected value of the insulation resistance is lower than the insulation resistance value before the ON command is output, the relay Rb other than the relay Rb from which the ON command is output is fixed to the relay Rb. Diagnose that has occurred. Thereby, this embodiment can diagnose ON fixation of relay Ra, Rb.

  In the present embodiment, in a state where all the relays Ra and Rb are turned off, one of the plurality of relays Ra or one of the plurality of relays Rb is turned on. Outputs a command. When the ON command is output to the relay Ra, if the detected value of the insulation resistance is not lower than the insulation resistance value before the output of the ON command, the relay Ra other than the relay Ra from which the ON command is output is sent to the relay Ra. Diagnose that no on-sticking has occurred. Further, when the ON command is output to the relay Rb, if the detected value of the insulation resistance is not lower than the insulation resistance value before the ON command is output, the relay Rb other than the relay Rb from which the ON command is output is output to the relay Rb. Diagnose that no on-sticking has occurred. Thereby, the state of relay Ra, Rb can be diagnosed.

  In this embodiment, when an off command for turning off all the switches of the relays Ra and Rb is output and the off command is output to the relays Ra and Rb, among the N battery bodies, a plurality of insulation resistances are output. When the detected value is lower than the normal value, it is diagnosed that the on-fixing has occurred in the relay Ra or the relay Rb included in the battery body M whose insulation resistance has decreased. Thereby, it is possible to diagnose the off-fixation of the relays Ra and Rb.

  Moreover, in this embodiment, when the off command which turns off all the switches of relay Ra, Rb is output and an off command is output to relay Ra, Rb, each detection value of the insulation resistance of N battery bodies Is lower than the normal value, it is diagnosed that the insulation resistance of the battery B included in the battery body M whose insulation resistance is lowered is lowered. Thereby, the state of the battery B can be diagnosed.

  In the present embodiment, an ON command for turning on the plurality of relays Ra or the plurality of relays Rb is output in a state where all the relays Ra and Rb are turned off. When the ON command is output to the plurality of relays Ra, if the detection value of the insulation resistance is not lower than the insulation resistance value up to the output of the ON command, the plurality of relays Ra to which the ON command is output are output. Of these, it is diagnosed that any one of the relays Ra is stuck off. When the ON command is output to the plurality of relays Rb, if the detected value of the insulation resistance is not lower than the insulation resistance value up to the output of the ON command, the plurality of relays to which the ON command is output A diagnosis is made that off-fixing has occurred in any one of the relays Rb. Thereby, it is possible to diagnose the off-fixation of the relays Ra and Rb.

  In the present embodiment, an ON command for turning on the plurality of relays Ra or the plurality of relays Rb is output in a state where all the relays Ra and Rb are turned off. When the ON command is output to the plurality of relays Ra, if the detected value of the insulation resistance is lower than the insulation resistance value up to the output of the ON command, it is fixed to the plurality of relays Ra to which the ON command is output. Diagnose that does not occur. In addition, when the ON command is output to the plurality of relays Rb, if the detected value of the insulation resistance is lower than the insulation resistance value up to the output of the ON command, the relays Rb to which the ON command is output are output. Diagnose that off sticking has not occurred. Thereby, the state of relay Ra, Rb can be diagnosed.

  In the present embodiment, both the plus-side relay Ra and the minus-side relay Rb are diagnosed, but only one of the plus-side and minus-side relays may be diagnosed. Further, the diagnosis of the negative relay Rb is performed after the diagnosis of the positive relay Ra, but the diagnosis of the negative relay Rb may be performed before the positive side.

In the present embodiment, after the state of the _first relay Ra ₁ is diagnosed, the state of the other relay Ra is diagnosed. However, the diagnosis is not necessarily limited to the _first relay Ra _1, and the diagnosis of the other relay Ra 1 is performed. You may go to the second.

In this embodiment, after confirming that the _first relay Ra ₁ is normal, an ON command is output to the _first relay Ra ₁ and the other relay Ra, and the other relay Ra ₁ Off sticking is diagnosed (corresponding to the control flow of steps S10 to S13). In the present embodiment, without determining that one relay Ra is normal, an ON command is output to the plurality of relays Ra, and an insulation resistance is detected, so that any one of the plurality of relays Ra is detected. The relay Ra may be diagnosed as being stuck on.

  The relay Ra corresponds to the “positive switch” according to the present invention, the relay Rb corresponds to the “negative switch” according to the present invention, and the insulation resistance detection circuit IR corresponds to the “insulation resistance detection means” according to the present invention. The relay control unit 22 corresponds to the “switch control unit” of the present invention, and the abnormality diagnosis unit 23 corresponds to the “abnormality diagnosis unit” of the present invention.

_{DESCRIPTION OF SYMBOLS} 10 ... Battery group 20 ... Controller 21 ... Battery management part 22 ... Relay control part 23 ... Abnormality diagnosis part 30 ... Load 100 ... Power supply B ... Battery GND ... Ground IR, _IR1-n ... Insulation resistance detection circuit M ... Battery body Ra, Rb, Ra1- _n , Rb1- _n ... Relay

Claims (6)

A battery group in which a plurality of battery bodies having a secondary battery, a positive switch connected to a positive electrode side of the secondary battery, and a negative switch connected to a negative electrode side of the secondary battery are connected in parallel; ,
Insulation resistance detection means for detecting insulation resistance of the battery body;
Switch control means for outputting a switching command for switching on and off the positive side switch and the negative side switch;
Abnormality diagnosis means for diagnosing an abnormality in at least one of the positive switch and the negative switch based on the detected value of the insulation resistance detected by the insulation resistance detection means and the switching command. ,
The switch control means includes
When diagnosing whether the positive switch or the negative switch is stuck off for the first time, two or more of the positive switch and the negative switch are turned off. Outputting a third switching command for turning on the positive switch and turning off the other positive switch, or turning on two or more negative switches and turning off the other negative switches;
When the third switching command is output to the positive switch or the negative switch, if the detected value of the insulation resistance is lower than the insulation resistance value before the output of the third switching command, the third switching command Turn off any one of the positive side switches that are turned on by the third switching command, turn on any one of the positive side switches that are turned off by the third switching command, Turn off the positive switch, or turn off any one of the negative switches that are turned on by the third switching command, and turn off the negative switch that is turned off by the third switching command A fourth switching command for turning on one of the negative switches and turning off the other negative switch; The force,
The abnormality diagnosis means includes
A power supply device that diagnoses whether the positive switch or the negative switch that is turned on by the third switching command and turned on by the fourth switching command is stuck off. The power supply device according to claim 1 , wherein
The switch control means includes
In a state where all of the positive side switch and the negative side switch are turned off, any one of the positive side switch among the plurality of positive side switches or any one of the plurality of negative side switches. A first on command to turn on the two negative switches is output;
The abnormality diagnosis means includes
When the first ON command is output to the positive switch, if the detected value of the insulation resistance is lower than the insulation resistance value before the output of the first ON command, the first ON command is output. Diagnosing that the positive switch other than the positive switch is stuck on, or
When the detected value of the insulation resistance is lower than the insulation resistance value before the output of the first on command when the first on command is output to the negative switch, the first on command is output. A power supply apparatus that diagnoses that the negative switch other than the negative switch is stuck on. The power supply device according to claim 2 , wherein
The abnormality diagnosis means includes
If the detected value of the insulation resistance is not lower than the insulation resistance value before the output of the on command when the first on command is output to the positive switch, the plurality of positive switches are fixed on. Is diagnosed as not occurring, or
If the detected value of the insulation resistance is not lower than the insulation resistance value before the output of the on command when the first on command is output to the negative switch, the plurality of negative switches are fixed on. A power supply that diagnoses that no fault has occurred. In the power supply device according to any one of claims 1 to 3 ,
The switch control means includes
Output an off command to turn off all of the positive side switch and the negative side switch,
The abnormality diagnosis means includes
When the off command is output to the switch, the detection value of the insulation resistance of any one of the plurality of battery bodies is lower than a normal threshold indicating normal insulation resistance, The power supply device which diagnoses that the insulation resistance of the said secondary battery contained in the said battery body in which insulation resistance fell is falling. In the power supply device according to any one of claims 1 to 4 ,
The switch control means includes
In a state where all of the positive side switch and the negative side switch are turned off, a plurality of the positive side switches or a plurality of the negative side switches are turned on, and a second on command is output.
The abnormality diagnosis means includes
When the second ON command is output to the positive switch, if the detected value of the insulation resistance is not lower than the insulation resistance value before the output of the second ON command, an ON command is output. Diagnosing that any one of the plurality of positive side switches is stuck off, or
When the second ON command is output to the negative switch, if the detected value of the insulation resistance is not lower than the insulation resistance value before the output of the second ON command, an ON command is output. A power supply apparatus that diagnoses that any one of the plurality of negative switches is stuck off. The power supply device according to claim 5 , wherein
The abnormality diagnosis means includes
When the detection value of the insulation resistance is lower than the insulation resistance value before the output of the second on command when the second on command is output to the positive switch, the on command is output. Diagnose that the positive switch is not stuck off, or
When the detected value of the insulation resistance is lower than the insulation resistance value before the output of the second on command when the second on command is output to the negative side switch, the on command is output. A power supply unit that diagnoses that the negative switch is not stuck off.

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