JP2012217276A - Power supply and vehicle having the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress power consumption of a shunt resistor with an inexpensive configuration and to enable accurate detection of current by the shunt resistor.SOLUTION: A power supply comprises: one or more batteries; a shunt resistor 10 connected in series with the batteries; and a current calculation circuit 5 for calculating a battery current by detecting a voltage induced by the electric conduction to the shunt resistor 10. The shunt resistor 10 can connect a plurality of shunt resistors 10 of the same type, in series or parallel in apart states. By this, with an extremely simple configuration of parallel connection of the shunt resistors of the same type, it is possible to obtain combined resistance 1/2 or smaller, to make conduction of a current value two-fold or greater, and to easily improve the rating two-fold or greater, with an advantage of being capable of current measurement even in the case of the conduction of a large current.

Description

  The present invention relates to a power supply device in which a shunt resistor is connected in series with a battery, and a voltage induced by the shunt resistor is detected to detect the current of the battery. The present invention relates to a power supply apparatus that is optimal for a power supply that is charged and discharged with a large current, such as a power supply that supplies power.

  The power supply apparatus includes a current sensor that detects a charging current and a discharging current of the battery. A power supply device including a current sensor can calculate the remaining capacity by integrating the battery current, and can control charging / discharging of the battery with the calculated remaining capacity, thereby preventing overcharging and overdischarging of the battery. Batteries have the property of deteriorating significantly due to overcharging and overdischarging. By accurately detecting the remaining capacity of the battery and preventing overcharging and overdischarging, it is possible to effectively prevent deterioration and extend its life. There is. However, to achieve this, it is important to accurately detect the battery current. This is because the battery current detection error becomes the calculation error of the remaining battery capacity. In particular, since the remaining capacity of the battery is calculated from the integrated value of the current, if there is a current detection error, the detection error gradually accumulates, which has a detrimental effect of gradually increasing the remaining capacity calculation error.

  The current sensor is generally configured to calculate a current from a voltage output in proportion to the electric resistance of the shunt resistor. FIG. 11 shows a circuit diagram of a power supply device that detects current with a shunt resistor. The power supply device shown in this figure detects the voltage across the shunt resistor 10 connected in series with the battery with a voltage detection circuit, and calculates the current value from the resistance value of the known shunt resistor. This shunt resistor is made of a metal plate. The shunt resistor of the metal plate is suitable for detecting a large current because it has a small electric resistance and excellent heat dissipation characteristics, and is used for a current sensor of a large current power supply device for vehicles and the like.

JP 2010-19603 A JP 2008-123868 A JP 2003-61252 A

The shunt resistor consumes electric power that is proportional to the square of the flowing current due to heat generated by Joule heat. For this reason, when a large current flows through the shunt resistor, there is a possibility that the shunt resistor and the jig holding the shunt resistor may be melted due to heat generated during energization. In order to reduce the power consumption of the shunt resistor, it is necessary to reduce the electrical resistance of the shunt resistor.
However, reducing the resistance value leads to an increase in the size of the shunt resistor itself, so that it is not easy to place in the power supply device, and even if a shunt resistor with a low resistance value can be manufactured, a large manufacturing die is required. Therefore, the manufacturing cost becomes high. Furthermore, if the resistance value is decreased, the current detection gain decreases, and therefore it is conceivable that the accuracy of current detection decreases. On the other hand, it is conceivable to increase heat dissipation by increasing the area of the shunt resistor without changing the resistance value, but this method increases the cost.

  The present invention has been developed for the purpose of solving the above drawbacks. A main object of the present invention is to provide a power supply device capable of suppressing power consumption of a shunt resistor with an inexpensive configuration and accurately detecting a current with the shunt resistor, and a vehicle including the same.

Means for Solving the Problems and Effects of the Invention

  In order to achieve the above object, according to the power supply device of the first aspect of the present invention, one or more batteries, a shunt resistor 10 connected in series with the batteries, and the shunt resistor 10 energized. And a current calculation circuit 5 that detects the induced voltage and calculates the current of the battery, wherein the shunt resistor 10 has a plurality of shunt resistors 10 of the same type separated from each other. Can be connected in series or in parallel. This makes it possible to make the combined resistance more than twice or less than 1/2 with a very simple configuration in which the same type of shunt resistors are connected in series or in parallel. This makes it possible to easily improve the gain by 2 times or more or the rating by 2 times or more, and obtain an advantage that current measurement corresponding to a small current or a large current is possible.

  Moreover, according to the power supply device which concerns on a 2nd side surface, the said same type shunt resistance 10 can be made into the same type shunt resistance 10 which consists of a single metal or an alloy.

  Furthermore, according to the power supply device which concerns on a 3rd side surface, the series-parallel changeover switch 20 connected further to the both ends of the said shunt resistance 10 is further provided, and the said series-parallel changeover switch 20 is the connection state of several shunt resistance 10. , The parallel state and the serial state can be switched. As a result, the shunt resistor can be easily changed to parallel connection or series connection. The shunt resistor connected in series has an advantage that the gain can be improved by setting the combined resistance to twice or more, and the resistance value of the shunt resistor can be selected according to the application.

  Furthermore, according to the power supply device according to the fourth aspect, the series-parallel changeover switch 20 sets the connection state of the shunt resistor 10 when the current is large according to the amount of current flowing through the plurality of shunt resistors 10. In parallel connection, when load current is small, it can be switched to serial connection. As a result, it is possible to achieve both improvement in detection accuracy and suppression of heat generation by switching shunt resistance selection according to the amount of current.

  Furthermore, according to the power supply device according to the fifth aspect, the postures of the shunt resistors 10 connected in parallel can be made different from each other. Thereby, the advantage which can cancel the influence of a thermoelectromotive force is acquired.

  Furthermore, according to the power supply device according to the sixth aspect, the posture of the shunt resistor 10 connected in parallel can be made the same direction. Thereby, since the thermoelectromotive force works in the same direction, it can be calculated and subtracted.

  Furthermore, according to the power supply device of the seventh aspect, the shunt resistor 10 can be provided with a voltage detection terminal protruding between the pair of current conducting terminals.

  Furthermore, according to the power supply device of the eighth aspect, the remaining capacity of the battery is calculated based on the induced voltage of the shunt resistor 10 and the charge / discharge current of the battery calculated by the current calculation circuit 5. And a control circuit for controlling charging / discharging of the battery.

  Furthermore, according to the ninth vehicle, the power supply device can be mounted.

It is a block diagram of the power supply device which concerns on one embodiment of this invention. It is a disassembled perspective view which shows the connection state of shunt resistance. It is a schematic diagram which shows the serial and parallel switching by a serial / parallel changeover switch. It is a block diagram which shows the power supply device which connected two shunt resistance in series. FIG. 5B is a plan view of the shunt resistor, and FIG. 5A is a diagram in which different currents are applied to the shunt resistor at the + side, the − side, and the center of the shunt resistor in FIG. It is a table | surface which shows the result of having measured the temperature of this. It is a schematic diagram which shows the example which connected shunt resistance in parallel in mutually different directions. It is a schematic diagram which shows the example which connected shunt resistance in parallel in the same direction. It is a block diagram which shows the example which mounts a power supply device in the hybrid car which drive | works with an engine and a motor. It is a block diagram which shows the example which mounts a power supply device in the electric vehicle which drive | works only with a motor. It is a block diagram which shows the example applied to the power supply device for electrical storage. It is a circuit diagram which shows the power supply device which detects an electric current with shunt resistance.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the embodiment described below exemplifies a power supply device for embodying the technical idea of the present invention and a vehicle including the power supply device, and the present invention includes the following power supply device and a vehicle including the power supply device. Not specified. Further, the present specification by no means specifies the members shown in the claims to the members of the embodiments. In particular, the dimensions, materials, shapes, relative arrangements, and the like of the component parts described in the embodiments are not intended to limit the scope of the present invention unless otherwise specified, and are merely explanations. It is just an example. Note that the size, positional relationship, and the like of the members shown in each drawing may be exaggerated for clarity of explanation. Furthermore, in the following description, the same name and symbol indicate the same or the same members, and detailed description thereof will be omitted as appropriate. Furthermore, each element constituting the present invention may be configured such that a plurality of elements are constituted by the same member and the plurality of elements are shared by one member, and conversely, the function of one member is constituted by a plurality of members. It can also be realized by sharing.

  FIG. 1 shows a power supply device 100 for a vehicle mounted on a hybrid car, a plug-in hybrid car, an electric vehicle or the like as an example of the power supply device according to the present invention. In addition, the power supply device of this invention can be used not only for electric vehicles, such as a hybrid car, but for all uses charged / discharged with a large current. A power supply device 100 shown in FIG. 1 includes a battery 1 that supplies electric power to a motor 93 that drives a vehicle via a DC / AC inverter 95, a shunt resistor 10 connected in series with the battery 1, and the shunt resistor. And a current calculation circuit 5 that detects the current induced in the battery 1 and detects the current of the battery 1. The power supply device 100 detects a current with a current detection circuit including a shunt resistor 10 and a current calculation circuit 5.

  A power supply device 100 in FIG. 1 includes a battery 1 that is a traveling battery that supplies power to a motor 93 that travels a vehicle, a contactor 2 that connects an output side of the battery 1 to a vehicle-side load 90, and the contactor 2. A precharge circuit 3 including a series circuit of a precharge resistor 7 and a precharge relay 6 connected in parallel to precharge the load capacitor 97 of the vehicle-side load 90, and the precharge relay 6 and the contactor 2 are controlled to be turned on and off. And a control circuit 4.

  The battery has a plurality of secondary battery cells 1a connected in series to increase the output voltage so that high power can be supplied to the motor 93 that drives the vehicle. The secondary battery cell 1a is a lithium ion battery or a nickel metal hydride battery. However, instead of lithium ion batteries and nickel metal hydride batteries, all rechargeable batteries can be used for the secondary battery cells. The battery adjusts the output voltage with the number of secondary battery cells 1 a connected in series so that a large amount of power can be supplied to the motor 93. In the battery, for example, the secondary battery cells 1a are connected in series so that the output voltage is 100V to 400V. However, although not shown, the power supply device can connect a boosting DC / DC converter to the output side of the battery to boost the voltage of the battery and supply power to the load. This power supply device can increase the output voltage of the battery by reducing the number of secondary batteries connected in series.

  The battery of FIG. 1 has two sets of battery blocks 1A connected in series. The battery block 1A has a plurality of secondary battery cells 1a connected in series. Further, the fuse 8 is connected between the two sets of battery blocks 1 </ b> A, and the two sets of battery blocks 1 </ b> A are connected in series via the fuses 8. In FIG. 1, two battery blocks are connected in series, and a fuse is connected between the two battery blocks. However, the present invention is not limited to this configuration, and a plurality of battery blocks are connected in parallel and then connected in series. You may make the structure of many parallel and straight connected. Thus, the number of battery blocks used, the connection configuration, and the like can be changed as appropriate.

  The contactor 2 is a relay having a contact that is switched on by energizing the coil. The power supply device 100 in FIG. 1 has a contactor 2 connected to both the positive and negative output sides of the battery 1 and is connected to a vehicle-side load 90 via the contactor 2. The positive contactor 2A is connected between the positive electrode side of the battery and the positive output terminal 9A which is the output terminal 9, and the negative contactor 2B is negative electrode which is the negative electrode side of the battery and the output terminal 9. And the output terminal 9B on the side. The contactor 2A on the plus side and the contactor 2B on the minus side are controlled by the control circuit 4 and the contacts are switched on and off. However, the power supply device does not necessarily need to connect a contactor to the positive and negative output sides, and can also connect a contactor to one output side.

  Before the contactor 2 is turned on, the precharge circuit 3 precharges the large-capacity load capacitor 97 connected to the vehicle side, thereby reducing the charge current flowing through the contactor 2 that is turned on. To do. The precharge circuit 3 includes a precharge resistor 7 and a precharge relay 6, and the precharge relay 6 and the precharge resistor 7 are connected in series and connected to the contactor 2 in parallel. The precharge circuit 3 switches on the contact of the precharge relay 6 to precharge the load capacitor 97. The precharge relay 6 is controlled by the control circuit 4 and the contact is switched on and off.

  The precharge circuit 3 is connected to the contactor 2 in parallel. The power supply device 100 in FIG. 1 has a precharge circuit 3 connected in parallel with the plus-side contactor 2A. The power supply device 100 keeps the contact of the positive contactor 2A off and switches the contact of the negative contactor 2B on. In this state, the contact of the precharge relay 6 is switched on and the precharge circuit is switched on. 3 to precharge the load capacitor 97. When the load capacitor 97 is precharged, the contact of the plus side contactor 2A is switched from OFF to ON, and the battery 1 is connected directly to the vehicle side load 90, that is, without a resistor. In this state, a state where electric power can be supplied from the power supply device 100 to the vehicle-side load 90, that is, a state where the motor 93 is driven by a battery and the vehicle can be driven is set. Thereafter, the precharge relay 6 of the precharge circuit 3 is switched off. When switching the contact of the contactor 2 in the on state to off, both contactors 2 are simultaneously turned off.

  The control circuit 4 controls the contactor 2 to be turned on / off by a request signal from a vehicle side ECU (not shown). Basically, in a state where the ignition switch of the vehicle is turned on, that is, in a state where the vehicle is running, the contactor 2 is turned on so that electric power can be supplied from the battery to the vehicle side. At this time, as described above, after the vehicle-side load capacitor 97 is precharged by the precharge circuit 3, the plus-side contactor 2A is switched on. When the ignition switch is switched off, the control circuit 4 switches the contactor 2 off.

  In the battery 1, the charge / discharge current is controlled so as to have a predetermined remaining capacity so that the electrical performance does not deteriorate due to overcharge or overdischarge and the life of the battery is extended. The remaining capacity of the battery 1 is calculated from the integrated value of the charging current and discharging current flowing through the battery 1. That is, the remaining capacity of the battery 1 is calculated by adding the integrated value of the charging current and subtracting the integrated value of the discharging current.

  The DC / AC inverter 95 converts the direct current supplied from the battery 1 into a three-phase alternating current and supplies it to the motor 93, and converts the alternating current power of the generator 94 into a direct current to charge the battery 1. The power supply device 100 controls the DC / AC inverter 95 to control the power supplied from the battery 1 to the motor 93, and also controls the power to charge the battery 1 from the generator 94, so that the battery 1 It is also possible to control the remaining capacity.

  The pair of current conducting terminals 11 are connected to the connection lead 13 and connected in series with the battery 1 via the connection lead 13. The connection lead 13 is a lead plate 13X made of a metal plate having a small electric resistance, or a lead wire provided with a connection terminal at the end. The shunt resistor 10 in FIG. 2 is connected between the two sets of battery blocks 1A, and connects the two sets of battery blocks 1A in series. The shunt resistor 10 is connected between the two battery blocks 1A and connected in series with the battery 1. However, the shunt resistor is connected to the output side and input side of the battery and connected in series with the battery. You can also.

  The pair of voltage detection terminals 12 are connected to the current calculation circuit 5. The current energizing terminal 11 and the voltage detection terminal 12 are provided with through holes 11a and 12a through which a set screw 15 for connecting a connection lead 13 made of a lead wire or a lead plate is inserted. The current energizing terminal 11 and the voltage detection terminal 12 are fixed so that the connection leads 13 and 14 which are lead plates and lead wires are electrically connected by set screws 15 inserted into the through holes 11a and 12a. However, the method of fixing the shunt resistor is not limited to that of the embodiment.

  The shunt resistor 10 of the power supply device 100 shown in FIG. 2 is made of a metal plate having a predetermined electrical resistance, and has a pair of current conducting terminals 11 at both ends. Further, a pair of voltage detection terminals 12 are provided between the pair of current conducting terminals 11 and projecting to the side of the metal plate.

The shunt resistor 10 of FIG. 2 has a connection lead 13 fixed to a current conducting terminal 11 via a set screw 15. The set screw 15 is inserted into both the shunt resistor 10 and the connection lead 13, and a nut 19 is screwed into the tip portion to fix the connection lead 13 to the current conducting terminal 11 of the shunt resistor 10. The set screw 15 is inserted into the through hole 13 a of the connection lead 13 and the through hole 11 a of the shunt resistor 10, and the connection lead 13 is fixed to the current conducting terminal 11. In FIG. 2, although the shape of the through hole is a round hole, it can be appropriately changed, for example, to make it a long hole.
(Shunt resistor 10)

In order to detect the charge / discharge current flowing in the battery 1, a shunt resistor 10 is connected in series with the battery 1. As shown in FIG. 2, the shunt resistor 10 is a metal plate having a predetermined electric resistance and generates a voltage in proportion to the current of the battery 1. That is, the voltage drop (E) generated in the shunt resistor 10 is specified by the following equation from the electric resistance (R) of the shunt resistor 10 and the flowing current (I).
E = R × I

From this equation, the current of the battery 1 is calculated by detecting the voltage drop of the shunt resistor 10. The electric resistance (R) of the shunt resistor 10 is set as small as possible. This is because the power consumed by the shunt resistor increases in proportion to the product of the square of the electric resistance (R) and the current (I). In addition, since the shunt resistance that increases power consumption also increases the amount of heat generation, the electrical resistance (R) is set small. The shunt resistor 10 having a small electric resistance (R) has a small power loss, but a generated voltage with respect to a current is also small.
(Current calculation circuit 5)

The current calculation circuit 5 detects the charge / discharge current of the battery 1 from the induced voltage of the shunt resistor 10. That is, the current that enters the shunt resistor 10 can be calculated by dividing the induced voltage across the shunt resistor 10 whose resistance value is known by the resistance value. In the example of FIG. 1, the current calculation circuit 5 is incorporated in the control circuit 4. The control circuit 4 can be composed of an ASIC or the like. The control circuit 4 detects the remaining capacity of the battery 1 from the detected current and controls charging / discharging of the battery 1. Thereby, the remaining capacity of the battery can be accurately detected, and the battery 1 can be charged and discharged while preventing overcharge and overdischarge, thereby extending the life.
(Parallel connection)

  A plurality of shunt resistors 10 are connected in parallel. In the example of FIG. 1, two shunt resistors 10 are connected in parallel. Each shunt resistor 10 is of the same type. As a result, the value of the combined resistance can be halved compared with the case where the number of the shunt resistors 10 is one, and the resistance value of the shunt resistor can be substantially reduced very easily. In addition, since the same current as in the case of one shunt resistor 10 can be passed through each shunt resistor 10 connected in parallel, the apparent current value can be doubled, the rated current can be doubled, and the large current Can be energized.

  In this way, by connecting a plurality of shunt resistors 10 in parallel, the voltage drop is smaller and the detection accuracy is lower than in the case where there is one shunt resistor having the same resistance value, but the current flowing through each shunt resistor is reduced. , And the amount of heat generated can be reduced accordingly. This is advantageous especially when the load current is large. Further, since the amount of generated heat can be suppressed, even if the number of shunt resistors increases, the shape of each shunt resistor can be reduced, and the size can be reduced.

  Further, a degree of freedom can be obtained in the arrangement of the shunt resistors. That is, by dividing the shunt resistor into a plurality of parts, the shunt resistor can be arranged according to the storage space, and an advantage that the limited storage space can be effectively used is also obtained. Further, by disposing the shunt resistors apart from each other, it is possible to disperse the heat source and improve the heat dissipation.

In addition, by using the same type of shunt resistor in parallel, it is possible to cope with a small manufacturing mold without requiring a large manufacturing mold, so that the development cost invested in manufacturing can be reduced. In addition, it is possible to use a single shunt resistor of the same type for a power supply device with a small output voltage scale, for example, by itself, and use a large number of shunt resistors of the same type for a power supply device with a large output voltage scale. Therefore, it is possible to produce a small-scale to large-scale power supply device with a single mold for manufacturing.
(Series-parallel switch 20)

  In addition, the parallel connection of the shunt resistors 10 can be switched to a serial connection. For switching the connection state, a series / parallel changeover switch 20 for switching the connection between the contacts can be used. An example of the series-parallel switch 20 is shown in FIG. The series-parallel changeover switch 20 shown in this figure is provided between the first shunt resistor 10A and the second shunt resistor 10B connected in parallel, and a pair of first arms 21 that connect the shunt resistors in parallel, And a second arm 22 connected in series. Each of the first arm 21 and the second arm 22 is movable using a solenoid coil (not shown), and can open and close the contacts.

  Further, the first shunt resistor 10A and the second shunt resistor 10B each have a connecting lead fixed via the left and right through holes 11a. The first connection lead 13A is on the left side of the first shunt resistor 10A, the second connection lead 13B is on the right side, the third connection lead 13C is on the left side of the second shunt resistor 10B, and the fourth connection lead 13D is on the right side. , Each fixed. Further, the first connection lead 13A is provided with a first contact piece 24A, the second connection lead 13B is provided with a second contact piece 24B, and the third connection lead 13C is provided with a third contact piece 24C and a fourth connection piece. A fourth contact piece 24D is provided on each lead 13D. In FIG. 3, the left first arm 21A connects the first contact piece 24A and the third contact piece 24C. The right first arm 21B connects the second contact piece 24B and the fourth contact piece 24D.

When the first arms 21 close the contacts, the first shunt resistor 10A and the second shunt resistor 10B can be connected in parallel. At this time, the second arm 22 is in the open position. On the other hand, the second arm 22 connects the second contact piece 24B and the third contact piece 24C. When the first arm 21 is in the open position and the second arm 22 is closed and the second contact piece 24B and the third contact piece 24C are connected, the first shunt resistor 10A and the second shunt resistor 10B are connected in series. can do. Note that switching between the arms is preferably provided with a delay in order to avoid a short circuit.
(Direct connection)

  An example of a circuit in which two shunt resistors 10 are connected in series is shown in FIG. The shunt resistor 10 connected in series is advantageous in that the gain can be improved by doubling the combined resistance. In other words, compared to the case where there is one shunt resistor having the same resistance value, by doubling the resistance value, the total amount of heat generation increases, but the voltage drop increases, and the detection accuracy increases accordingly. Even when the load current is small, accurate current detection is possible.

  Thus, by providing the series / parallel changeover switch, the parallel connection of the shunt resistor can be switched to the series connection, and the resistance value of the shunt resistor can be changed according to the application. In particular, the shunt resistor parallel connection and series connection can be easily selected by the ON / OFF switching operation of the series / parallel switch. For example, by switching the selection according to the amount of current, the detection accuracy can be improved and the amount of generated heat can be suppressed. It is possible to achieve both. In addition, since power consumption can be suppressed by suppressing the amount of heat generation, wasteful power consumption can be minimized and the battery performance can be utilized to the maximum.

  In the above example, an example using two shunt resistors has been described, but it goes without saying that three or more shunt resistors can be used. In the above example, the configuration in which the series connection and the parallel connection of the shunt resistor are switched via the series / parallel changeover switch has been described. However, the shunt resistor can be used in a state of being fixed to the series connection. In this case, the series / parallel switch may be omitted.

Furthermore, in a configuration in which a plurality of shunt resistors are connected in series, it is possible to provide a plurality of detection ranges by detecting a voltage in the middle of the series connection, and a gain circuit for making the detection range variable is unnecessary. And can.
(Thermo-electromotive force)

  On the other hand, since a thermoelectromotive force is generated in the shunt resistor due to a temperature difference between the left and right voltage detection terminals, a detection error occurs. FIG. 5A shows a table of the results of measuring the temperature when different currents are passed through the shunt resistor at the + side, − side, and center positions of the shunt resistor in FIG. In the figure, the positive side is a voltage detection terminal on the current inflow side, and the negative side is a voltage detection terminal on the current outflow side. As shown in this table, the temperature at each position when the current amount in the shunt resistor is energized does not match. As long as the shunt resistance is not physically equal to the left and right, unevenness is generated in heat dissipation, so it is considered that a temperature difference occurs between the + side and the − side, and a thermoelectromotive force is generated due to this temperature difference, resulting in an error current. The temperature difference is amplified by the current. The error increases exponentially.

  Although it is possible to reduce the influence of the thermoelectromotive force error due to spontaneous heat generation by manufacturing a physically completely symmetric shunt resistor, for example, the shunt resistor and the connecting lead wire are simultaneously tightened with a set screw. When manufacturing assembling property is improved by providing a hole for temporarily fixing the shunt resistor to the jig before, it is difficult to reduce the influence of the thermoelectromotive force due to spontaneous heat generation. Therefore, when the same type of shunt resistors are connected in parallel, the influence of the thermoelectromotive force can be offset by making the postures of the shunt resistors 10C and 10D different from each other vertically as shown in FIG. That is, the influence of the thermoelectromotive force error due to spontaneous heat generation can be reduced by the heat transfer of each shunt resistor.

Or conversely, as shown in FIG. 7, the postures of the shunt resistors 10C and 10D connected in parallel can be set in the same direction. According to such an arrangement, the thermoelectromotive force error due to spontaneous heat generation is also output equally, so the current difference, that is, the error of the thermoelectromotive force due to heat inflow from other places to the left and right voltage detection terminals is estimated and calculated. Can be eliminated. Further, since the thermoelectromotive force due to spontaneous heat generation is a function depending on the shape, material, and current of the shunt resistor, it can be dealt with by a preset correction function. The arrangement of the shunt resistors shown in FIGS. 6 and 7 is not limited to the arrangement of the shunt resistors. For example, the shunt resistors may be arranged in an inner posture such that the voltage detection terminals 12 of the two shunt resistors face each other ( 6 and 7, the upper shunt resistor 10C is inverted up and down), or conversely, the current-carrying terminals 11 can be arranged so as to face each other (see FIG. 6 and FIG. 7). 6 and 7, the lower shunt resistor 10 </ b> D is inverted up and down). Thus, the attitude | position which arrange | positions shunt resistance can be changed suitably, and the shape of shunt resistance is not limited to the thing of an Example.
(vehicle)

  As described above, this power supply device can be used as an in-vehicle battery system. As a vehicle equipped with a power supply device, an electric vehicle such as a hybrid car or a plug-in hybrid car that runs with both an engine and a motor, or an electric car that runs only with a motor can be used, and it is used as a power source for these vehicles. .

  FIG. 8 shows an example in which a power supply device is mounted on a hybrid car that runs with both an engine and a motor. A vehicle HV equipped with the power supply device shown in this figure includes an engine 96 and a travel motor 93 that travel the vehicle HV, a power supply device 100 that supplies power to the motor 93, and a generator that charges a battery of the power supply device 100. 94. The power supply apparatus 100 is connected to a motor 93 and a generator 94 via a DC / AC inverter 95. The vehicle HV travels by both the motor 93 and the engine 96 while charging / discharging the battery of the power supply device 100. The motor 93 is driven to drive the vehicle when the engine efficiency is low, for example, during acceleration or low-speed driving. The motor 93 is driven by power supplied from the power supply device 100. The generator 94 is driven by the engine 96 or is driven by regenerative braking when the vehicle is braked to charge the battery of the power supply device 100.

FIG. 9 shows an example in which a power supply device is mounted on an electric vehicle that runs only with a motor. A vehicle EV equipped with the power supply device shown in this figure includes a traveling motor 93 for traveling the vehicle EV, a power supply device 100 that supplies power to the motor 93, and a generator 94 that charges a battery of the power supply device 100. And. The motor 93 is driven by power supplied from the power supply device 100. The generator 94 is driven by energy when regeneratively braking the vehicle EV and charges the battery of the power supply device 100.
(Power storage device for power storage)

  Furthermore, this power supply device can be used not only as a power source for a moving body such as a vehicle, but also as a stationary power storage facility. For example, as a power source for households and factories, a power supply system that is charged with solar power or midnight power and discharged when necessary, or a street light that is charged with solar power during the day and discharged at night It can also be used as a backup power source for traffic lights that are driven in the event of a power failure. Such an example is shown in FIG. The power supply apparatus 100 shown in this figure forms a battery unit 82 by connecting a plurality of battery packs 81 in a unit shape. In each battery pack 81, a plurality of secondary battery cells 1a are connected in series and / or in parallel. Each battery pack 81 is controlled by a power controller 84. The power supply apparatus 100 drives the load LD after charging the battery unit 82 with the charging power supply CP. For this reason, the power supply apparatus 100 includes a charging mode and a discharging mode. The load LD and the charging power source CP are connected to the power supply device 100 via the discharging switch DS and the charging switch CS, respectively. ON / OFF of the discharge switch DS and the charge switch CS is switched by the power supply controller 84 of the power supply apparatus 100. In the charging mode, the power supply controller 84 switches the charging switch CS to ON and the discharging switch DS to OFF to permit charging from the charging power supply CP to the power supply apparatus 100. Further, when the charging is completed and the battery is fully charged, or in response to a request from the load LD in a state where a capacity of a predetermined value or more is charged, the power controller 84 turns off the charging switch CS and turns on the discharging switch DS to discharge. The mode is switched to permit discharge from the power supply apparatus 100 to the load LD. Further, if necessary, the charge switch CS can be turned on and the discharge switch DS can be turned on to supply power to the load LD and charge the power supply device 100 at the same time.

  A load LD driven by the power supply apparatus 100 is connected to the power supply apparatus 100 via a discharge switch DS. In the discharge mode of the power supply apparatus 100, the power supply controller 84 switches the discharge switch DS to ON, connects to the load LD, and drives the load LD with the power from the power supply apparatus 100. As the discharge switch DS, a switching element such as an FET can be used. ON / OFF of the discharge switch DS is controlled by the power supply controller 84 of the power supply apparatus 100. The power controller 84 also includes a communication interface for communicating with external devices. In the example of FIG. 10, it is connected to the host device HT according to an existing communication protocol such as UART or RS-232C. Further, if necessary, a user interface for the user to operate the power supply system can be provided.

  Each battery pack 81 includes a signal terminal and a power supply terminal. The signal terminals include a pack input / output terminal DI, a pack abnormality output terminal DA, and a pack connection terminal DO. The pack input / output terminal DI is a terminal for inputting / outputting signals from other pack batteries and the power supply controller 84, and the pack connection terminal DO is for inputting / outputting signals to / from other pack batteries which are child packs. Terminal. The pack abnormality output terminal DA is a terminal for outputting the abnormality of the battery pack to the outside. Furthermore, the power supply terminal is a terminal for connecting the battery packs 81 in series and in parallel. The battery units 82 are connected to the output line OL via the parallel connection switch 85 and are connected in parallel to each other.

  The power supply device according to the present invention and the vehicle including the power supply device can be suitably used as a power supply device for a plug-in hybrid electric vehicle, a hybrid electric vehicle, an electric vehicle, or the like that can switch between the EV traveling mode and the HEV traveling mode. Also, a backup power supply device that can be mounted on a rack of a computer server, a backup power supply device for a wireless base station such as a mobile phone, a power storage device for home use and a factory, a power supply for a street light, etc. Also, it can be used as appropriate for applications such as a backup power source such as a traffic light.

DESCRIPTION OF SYMBOLS 100 ... Power supply device 1 ... Battery; 1A ... Battery block; 1a ... Secondary battery cell 2 ... Contactor; 2A ... Positive side contactor; 2B ... Negative side contactor 3 ... Precharge circuit 4 ... Control circuit 5 ... Current calculation circuit 6 ... Precharge relay 7 ... Precharge resistor 8 ... Fuse 9 ... Output terminal; 9A ... Positive output terminal; 9B ... Negative output terminal 10, 10C, 10D ... Shunt resistor 10A ... First shunt resistor; 10B ... 2nd shunt resistance 11 ... Current conduction terminal; 11a ... Through hole 12 ... Voltage detection terminal; 12a ... Through hole 13 ... Connection lead; 13A ... First connection lead; 13B ... Second connection lead 13C ... Third connection lead; ... 4th connection lead 13X ... Lead plate; 13a ... Through-hole 15 ... Set screw 19 ... Nut 20 ... Series-parallel changeover switch 21 ... 1st arm; 2 A ... left first arm; 21B ... right first arm 22 ... second arm 24A ... first contact piece 24B ... second contact piece 24C ... third contact piece 24D ... fourth contact piece 81 ... battery pack 82 ... Battery unit 84 ... Power controller 85 ... Parallel connection switch 90 ... Vehicle side load 93 ... Motor 94 ... Generator 95 ... DC / AC inverter 96 ... Engine 97 ... Load capacitor EV, HV ... Vehicle LD ... Load; CP ... Charging power source DS ... discharge switch; CS ... charge switch OL ... output line; HT ... host device DI ... pack input / output terminal; DA ... pack abnormal output terminal; DO ... pack connection terminal

Claims (9)

One or more batteries,
A shunt resistor (10) connected in series with the battery;
A power supply device comprising a current calculation circuit (5) for detecting a voltage induced by energizing the shunt resistor (10) and calculating a current of the battery,
A power supply device, wherein the shunt resistor (10) is formed by connecting a plurality of shunt resistors (10) of the same type in series or in parallel. The power supply device according to claim 1,
The power supply device according to claim 1, wherein the same type of shunt resistor (10) is the same type of shunt resistor (10) made of a single metal or alloy. The power supply device according to claim 1, further comprising:
A series-parallel changeover switch (20) connected to both ends of the shunt resistor (10) is provided,
The power supply device, wherein the series / parallel changeover switch (20) is configured to be able to switch between a parallel state and a series state when a plurality of shunt resistors (10) are connected. The power supply device according to claim 3,
The series / parallel changeover switch (20) is configured to change the connection state of the shunt resistor (10) according to the amount of current flowing through the plurality of shunt resistors (10). A power supply device that is switched to a serial connection when it is small. The power supply device according to any one of claims 1 to 4,
The power supply device according to claim 1, wherein the shunt resistors (10) connected in parallel have different orientations. The power supply device according to any one of claims 1 to 4,
The power supply apparatus according to claim 1, wherein the shunt resistors (10) connected in parallel have the same orientation. The power supply device according to any one of claims 1 to 6,
The power supply device, wherein the shunt resistor (10) has a voltage detection terminal protruding between a pair of current conducting terminals. The power supply device according to any one of claims 1 to 7, further comprising:
Based on the induced voltage of the shunt resistor (10) and the charge / discharge current of the battery calculated by the current calculation circuit (5), a control circuit that calculates the remaining capacity of the battery and controls the charge / discharge of the battery A power supply apparatus comprising:   A vehicle comprising the power supply device according to any one of claims 1 to 8.

Images