JP2011131701A - Electric power supply device for electric motor vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric power supply device for preventing reduction in durability caused when charging voltage for a low voltage battery is directly impressed on an auxiliary machine, in a system having a high voltage battery and the low voltage battery and charging the low voltage battery with the high voltage battery. <P>SOLUTION: A sub-battery 5 is charged with voltage stepped down by a down converter 6. This charging voltage is impressed on a lamp unit 27 and a headlight 25 by turning on a main switch 9. The headlight 25 is grounded via FET11 or 11a, and this FET 11 or 11a is driven by the low duty ratio, and thereby, an electric current supplied to the headlight 25 is limited to a rated current. The electric current flowing to the headlight 25 can be also reduced by the voltage step-down action of a diode D1 or D2. The FET 11 and 11a and the diode D1 and D2 can be mounted on a substrate of a PDU 45 and the down converter 6. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a power supply device for an electric vehicle, and more particularly to a high-voltage main battery that supplies power to an electric motor (hereinafter simply referred to as “motor”) that is a drive source of the vehicle, and a vehicle other than the motor. The present invention relates to a power supply device for an electric vehicle including a low-voltage sub-battery that supplies power to a power drive device (auxiliary machine).

  In general, vehicles such as motorcycles and passenger cars are equipped with a battery having a rated voltage of 12 volts as a power source. However, when an optional electrical component is installed or the performance of the vehicle is improved, the battery becomes higher. Vehicles equipped with a voltage battery are also known. However, a high voltage battery cannot light a low voltage rated lamp as usual. Therefore, for example, Patent Document 1 discloses a vehicle lamp that adjusts the current flowing through the lamp by changing the output duty ratio of the power converter so that a conventional low voltage rated lamp can be lit with a high voltage battery. Control devices have been proposed.

Japanese Patent No. 3679700

  In a power supply device for an electric vehicle equipped with a high-voltage battery, a low-voltage sub-device for auxiliary equipment is provided separately from the high-voltage battery, which is the main battery, for the purpose of stably supplying power to the auxiliary equipment of the vehicle, such as lighting equipment A battery may be provided. In this case, a system is conceivable in which the output voltage of the main battery is stepped down by a power converter and the sub-battery is charged with the stepped down voltage.

  In such a system, electric power is supplied from the sub-battery to the auxiliary equipment of the vehicle including the lighting device. However, since the voltage of the sub-battery is the charging voltage applied from the power converter, simply supplying the voltage from the power converter to the auxiliary machine, for example, charging the lamp with a voltage higher than its rated voltage. A voltage will be applied. Since lighting the lighting device with the charging voltage in this way may affect the durability of the lighting device, a countermeasure is desired.

  On the other hand, if the output voltage of the power converter is lowered in consideration of the durability of the lamp, there arises a problem that the sub battery cannot be charged sufficiently.

  An object of the present invention is to provide a power supply device for an electric vehicle that can prevent a decrease in durability of an auxiliary device such as a lighting device while allowing a sub-battery to be sufficiently charged with respect to the above-described problems of the prior art. It is to provide.

  The present invention for achieving the above object is used in an electric vehicle having a motor as a drive source of the vehicle and an auxiliary machine including at least a headlight, and has a high voltage main battery and a voltage lower than that of the main battery. The sub-battery power supply is configured to supply power to the auxiliary machine with the output voltage of the sub-battery and the output voltage of the main battery stepped down by the first power conversion means. In the apparatus, the first power conversion unit is configured to step down the output voltage of the main battery to generate a charging voltage for the sub battery, and further reduce the output voltage of the sub battery to compensate. There is a first feature in that it further comprises second power conversion means for supplying to the machine.

  Further, the present invention is a switching element in which the second power conversion means is controlled by a duty ratio so as to limit a voltage applied to the auxiliary machine, and the duty ratio is variable in accordance with a running state of the vehicle. There is a second feature at a certain point.

  The present invention also includes vehicle speed detection means for detecting the speed of the vehicle, and switches the duty ratio to a smaller value than when the vehicle is running when it is detected that the vehicle is stopped based on the detected vehicle speed. The point has the third feature.

  According to the present invention, the electric vehicle has a side stand that causes the vehicle to stand on its own, and a side stand switch that outputs a detection signal when the side stand is in the non-storage position, and the side stand switch outputs the detection signal. The fourth feature is that the duty ratio is switched to zero.

  In addition, the present invention has a fifth feature in that the charging voltage supplied to the sub-battery by the first power converter is higher than the rated voltage of the sub-battery.

  Further, the present invention has a sixth feature in that the second power conversion means is a diode having a voltage drop function.

  Further, according to the present invention, the first power conversion means is a first down converter, and the second power conversion means is a second down converter that further reduces the output voltage of the first down converter. The first down converter outputs a voltage for charging the sub battery, and the second down converter is connected to the sub battery and the auxiliary machine so as to output the driving voltage of the auxiliary machine. The point has the seventh feature. Furthermore, the present invention has an eighth feature in that when the main switch is turned on, the switching element is driven at a duty ratio of 100% until the first power conversion means operates.

  According to the present invention having the first feature, power can be stably supplied from the sub-battery to the auxiliary machine regardless of the drive load fluctuation of the main battery. In addition, a voltage sufficient to charge the sub-battery can be applied, and at the same time, the durability of auxiliary equipment such as a lighting device can be improved. In particular, the life of the bulb of the headlight can be extended.

  According to the present invention having the second feature, it is possible to adjust the illuminance of a lighting device that is an auxiliary device according to the state of the vehicle. For example, in the present invention having the third feature, since the lamp can be dimmed when the vehicle is stopped, the discharge time of the battery can be lengthened.

  According to the present invention having the fourth feature, when the side stand is in the non-retracted position, the lamp as an auxiliary device is turned off to increase the battery discharge time and increase the travel distance of the electric vehicle. it can.

  According to the present invention having the fifth feature, the sub-battery can be sufficiently charged. According to the present invention having the sixth feature, since the voltage can be limited by the function of the diode, unlike the case where the switching element is used, a control means or the like is unnecessary, and the configuration can be simplified.

  According to the present invention having the seventh feature, it is possible to extract two types of voltages stepped down with high accuracy. According to the present invention having the eighth feature, power is supplied from the sub-battery in view of the fact that power is supplied from the sub-battery to the headlights after the main switch is turned on until the output of the down converter starts. During this time, the brightness of the headlight can be maintained by driving the switching element with a 100% duty ratio.

It is a block diagram which shows the structure of the electric power supply apparatus which concerns on one Embodiment of this invention. It is a side view of the electric vehicle carrying the electric power supply apparatus which concerns on one Embodiment of this invention. It is a flowchart which concerns on duty ratio control of the electric current which flows into a headlight. It is a block diagram which shows the principal part of the electric power supply apparatus which concerns on 2nd Embodiment of this invention. It is a block diagram which shows the principal part of the electric power supply apparatus which concerns on 3rd Embodiment of this invention. It is a block diagram which shows the principal part of the electric power supply apparatus which concerns on 4th Embodiment of this invention. It is a block diagram which shows the principal part of the electric power supply apparatus which concerns on 5th Embodiment of this invention.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 2 is a left side view of the electric vehicle equipped with the power supply apparatus according to the embodiment of the present invention. The electric vehicle 1 is a scooter type motorcycle having a low floor, and each component is attached to the body frame 3 directly or indirectly through another member. First, the vehicle body frame 3 includes a head pipe 31 that is a front portion, a front frame portion 32 that has a front end joined to the head pipe 31 and a rear end extending downward, and a left and right direction in the vehicle body width direction from the front frame portion 32. It consists of a pair of main frame portions 33 that branch and extend toward the rear of the vehicle body, and a rear frame portion 36 that extends from the main frame portion 33 to the rear of the vehicle body.

  A front fork 2 that supports the front wheel WF is supported by the head pipe 31 so as to be steerable. A steering handle 46 having an accelerator grip is connected to an upper portion of a steering shaft 41 that extends upward from the front fork 2 and is supported by the head pipe 31. The steering handle 46 is provided with a throttle sensor 23 that detects the rotation angle of the accelerator grip, that is, the accelerator opening.

  A bracket 37 made of a pipe is coupled to the front portion of the head pipe 31, a headlight 25 is attached to the front end portion of the bracket 37, and a front carrier 26 supported by the bracket 37 is disposed above the headlight 25. Provided.

  A bracket 34 extending toward the rear of the vehicle body is joined to an intermediate region between the main frame portion 33 and the rear frame portion 36 of the vehicle body frame 3. The bracket 34 extends in the vehicle body width direction. A pivot shaft 35 is provided, and the swing arm 17 is supported by the pivot shaft 35 so as to be swingable up and down. The swing arm 17 is provided with a motor 18 as a vehicle drive source, and the output of the motor 18 is transmitted to the rear wheel axle 19 to drive the rear wheel WR supported by the rear wheel axle 19. The housing including the rear wheel axle 19 and the rear frame portion 36 are connected by the rear suspension 20.

  The bracket 34 is provided with a side stand 24 that supports the vehicle body when the vehicle is stopped. The side stand 24 includes a side stand switch 28 that outputs a detection signal when the side stand 24 is stored in a predetermined position.

  The main frame portion 33 is mounted with a main battery 4 having a high voltage (for example, 72 volt rating) composed of a plurality of battery cells, and the upper portion of the main battery 4 is covered with a cover 40. An air introduction pipe 38 is connected to the front portion of the main battery 4, and an intake fan 39 is provided at the rear portion of the main battery 4. Air is introduced into the main battery 4 from the air introduction pipe 38 by the intake fan 39, and the air is discharged to the rear of the vehicle body after the main battery 4 is cooled.

  A socket 44 is provided on the rear frame portion 36 to which a plug 43 of a charging cable 42 extending from a charger (not shown) for charging the main battery 4 can be coupled. The rear frame portion 36 is further provided with a rear carrier 29 and a taillight 27.

  A cargo compartment 50 is provided between the pair of left and right rear frame portions 36, and a cargo compartment bottom 51 protruding downward from the cargo compartment 50 has a low voltage (for example, 12 volt rating) charged by the main battery 4. ) Of the sub-battery 5 is accommodated. The swing arm 17 is provided with a power drive unit (PDU) 45 that controls the motor 18.

  A driver seat 21 that also serves as a lid of the luggage compartment 50 is provided on the luggage compartment 50, and the driver seat 21 has a seat switch 22 that operates when the driver is seated and outputs a seating signal. Provided.

  FIG. 1 is a block diagram illustrating a system configuration of the power supply apparatus. The power supply device is provided in the main battery 4, the sub battery 5, a DC-DC down converter (hereinafter simply referred to as “down converter”) 6 as a first power conversion means, a PDU 45, and the main battery 4. The battery management unit (BMU) 7 is provided. The PDU 45 includes an inverter circuit 451 formed of a switching element such as an FET or IGBT, and a control unit 452 that controls the inverter circuit 451. The control unit 452 includes a CAN communication board.

  The main battery 4 includes, for example, three sets of 24 volt lithium ion battery modules, and forms a battery pack together with the BMU 7 that can be configured by LSI. The main battery 4 is electrically connected to the input side of the inverter circuit 451 through power lines L1 and L2 via a relay device 8 including a contactor 81 and a precharge contactor 82 connected in parallel to each other. The three-phase AC output side of the inverter circuit 451 is connected to the motor 18 by a three-phase AC line.

  The power lines L1 and L2 are connected to the input side of the down converter 6 and to the charging socket 44. The down converter 6 has a function of converting a high voltage input (for example, the voltage of the main battery 4 which is 72 volts) into a low voltage (for example, a charging voltage of the sub battery 5) and outputting the converted voltage. The sub-battery 5 is a control power source for the control unit 452 and the auxiliary machine, and includes a 12-volt battery and is charged with, for example, 14.3 volts.

  The output of the down converter 6 is always connected to the system line L3, and the always system line L3 is connected to the BMU 7 and the sub battery 5. Further, the continuous system line L3 is connected to the main switch 9, and the main switch 9 is connected to the control unit 452, the BMU 7, the lighting device (taillight) 27, the headlight 25, and the general electrical equipment 10 by the main switch system line L4. Connected. An auto power off relay 14 is provided in the main switch system line L4.

  The headlight 25 is grounded via a switching element (FET) 11 provided in the control unit 452. An angle sensor 16 that detects the rotation angle of the motor 18, a throttle sensor 23, a seat switch 22, and a side stand switch 28 are connected to the control unit 452 of the PDU 45.

  A CAN communication line 12 is provided between the BMU 7 and the control unit 452. Further, signal lines 48 and 49 are respectively provided between the contactor 81 and the precharge contactor 82 of the BMU 7 and the relay device 8, and an opening / closing command for the contactor 81 and the precharge contactor 82 output from the BMU 7 is transmitted.

  The charging socket 44 is configured to be connectable to the power plug 13 connected to the output side of the charger 41 whose input side can be connected to the commercial AC power source. The charger 41 can generate an auxiliary power supply voltage, and the auxiliary power supply line L6 is connected to a control system line L5 that connects between the BMU 7 and the control unit 452.

  In the above configuration, when charging the main battery 4, the charging plug 43 is connected to the charging socket 44, and the power plug 13 is connected to an AC 100 volt outlet (not shown). Then, when a charging start switch (not shown) provided in the charger 41 is turned on, the auxiliary power supply voltage (12 volts) is applied from the charger 41 to the control system line L5 through the auxiliary power supply line L6.

  The auxiliary power supply voltage is applied to the control unit 452 and the BMU 7 of the PDU 45 via the control system line L5, and the control unit 452 starts operation when the auxiliary power supply voltage is applied. For example, it communicates with the BMU 7 by CAN communication, and transmits a contactor control signal to the BMU 7. The BMU 7 sequentially turns on the precharge contactor 82 and the contactor 81 in response to the contactor control signal. The reason why the precharge contactor 82 is turned on before the contactor 81 is to prevent the inrush current from flowing when the contactor 81 is suddenly turned on. The current adjusted by the resistor R is the main current. Supplied from the battery 4. Thus, current is supplied from the charger 41 through the power lines L1 and L2, and the main battery 4 is charged. In the CAN communication, an overcharge signal of the main battery is supplied from the BMU 7 to the control unit 452.

  Further, since the PDU 45 starts the down converter 6 in response to the input of the auxiliary voltage, the voltage stepped down by the down converter 6 is always connected to the system line L3. The sub-battery 5 is charged with the voltage (14.3 volts) connected to the regular system line L3.

  When the vehicle on which the charged main battery 4 is mounted is driven, first, the main switch 9 is turned on. Then, the voltage of the sub battery 5 is applied to the main switch system line L4, and the control unit 452 is driven by this voltage. Further, the auto power off relay 14 is turned on, and the voltage of the sub-battery 5 is applied to auxiliary equipment such as the lighting device 27, the headlight 25, and the general electrical equipment 10 via the main switch system line L4. The However, since the headlight 25 is grounded via the FET 11 provided in the control unit 452, a current controlled according to the on-time duty ratio of the FET 11 flows to the headlight 25. The control of the on-time duty ratio of the FET 11 will be further described later.

  When the voltage from the sub battery 5 is applied via the main switch 9, the control unit 452 inputs an activation signal to the down converter 6. The down converter 6 starts to operate in response to the activation signal, and steps down the voltage of the main battery 4 and outputs it to the system line L3. The voltage of the down-converted down-converter 6 is a voltage sufficient to charge the sub battery 5 (for example, 14.3 volts), and this voltage includes the headlight 25, the lamp 27, and the sub battery 5 in addition to the sub battery 5. It is also applied to general electrical equipment.

  When the throttle sensor 23 is opened with the main switch 9 turned on, it is assumed that the seat switch 22 and the side stand switch 28 are turned on, that is, the driver is seated on the seat 21. On the condition that the side stand 24 is raised to the storage position, the control unit 452 performs PWM control of the inverter circuit 451 and starts supplying power to the motor 18. The switching timing of the switching elements constituting the inverter circuit 451 is determined according to the rotation angle of the motor 18 by the angle sensor 16. The controller 452 can calculate the vehicle speed using the rotation angle detected by the angle sensor 16. Therefore, the angle sensor 16 also functions as a speed detection sensor for a vehicle driven by the motor 18. The duty ratio control in the PWM control is performed according to the opening detected by the throttle sensor 23.

  When the detected opening of the throttle sensor 23 is smaller than a predetermined value or at least one of the seat switch 22 and the side stand switch 25 is turned off, the control unit 452 sets the duty ratio instructed to the inverter circuit 451 to zero and drives the motor 18. To stop.

  When the main switch 9 is turned off, the auto power off relay 14 is turned off after a predetermined time elapses, and the power supply to the headlight 25 and other lighting devices 27 and the general electrical equipment 10 is stopped.

  Next, the control of the FET 11 that limits the current flowing through the headlight 25 will be described. FIG. 3 is a flowchart showing an operation related to duty ratio control of the headlight 25 in the power supply apparatus. In the figure, in step S1, it is determined whether or not the main switch 9 is on. If it is determined that the main switch 9 is turned on, the process proceeds to step S2 to activate the PDU 45. In step S3, the auto power off relay 14 is turned on. In step S4, the FET 11 constituting the dimming circuit as the second power conversion means is turned on. That is, the FET 11 is driven with a 100% duty ratio. Since it takes time until the output of the down converter 6 is started after the main switch 9 is turned on, electric power is supplied from the sub battery 5 to the headlight 25 during this time. Therefore, it is preferable to maintain the brightness of the headlight 25 by driving the FET 11 with a 100% duty ratio while power is supplied from the sub-battery 5 in this way.

  In step S5, it is determined whether or not the BMU 7 and the down converter 6 have started to start. This determination can be made based on the elapsed time since the main switch 9 was turned on, the output voltage of the down converter 6 reaching a predetermined value (14.3 volts), or the like.

  If step S5 is affirmative, the process proceeds to step S6, where the drive duty ratio of the FET 11 is reduced to reduce the current flowing through the headlight 25 to 90%, for example.

  In step S7, it is determined whether the rotation speed of the motor 18 is 0 rpm, that is, whether the motor 18 is stopped. If it is determined that the motor 18 is stopped, the process proceeds to step S8, where the duty ratio of the FET 11 is lowered to a lower value (for example, 70%) and further dimmed. This is because when the motor 18 is stopped, it can be determined that the vehicle is stopped, and therefore the headlight 25 may be dimmed.

  If step S7 is negative, that is, if it is determined that the motor 18 is not stopped, the process proceeds to step S9, where it is determined whether the side stand switch 28 is off, that is, whether the side stand 24 is out. When the side stand 24 is out, even if the rotation speed of the motor 18 is not 0 rpm, the process proceeds to step S10 and the duty ratio of the FET 11 is set to a low value (for example, 70%). This is because it may be determined that the vehicle is stopped when the side stand 24 is extended.

  When it is determined that the vehicle is stopped, the headlight 25 may be turned off as well as dimmed. Further, in step S7, instead of determining whether the rotation speed of the motor 18 is 0 rpm, it may be determined whether the vehicle is stopped based on the vehicle speed. For example, it may be determined whether or not the duty ratio is reduced to 70% based on whether or not the vehicle speed is 4 km / hour or less.

  In this way, by limiting the current supplied to the headlight 25, the headlight bulb can be switched to a higher rating even in a configuration in which a voltage exceeding the rating is applied to the headlight 25 having a lower rating. Therefore, the high durability of the headlight 25 can be maintained.

  The FET 11 that limits the current flowing through the headlight 25 has a function as a second power conversion unit with respect to the down converter 6 as the first power conversion unit that converts a high voltage into a charging voltage. Since the FET 11 is attached to an existing substrate in the PDU 45, the mountability can be improved.

  The FET 11 as the second power conversion means is not limited to being provided in the PDU 45 but can be provided, for example, in the down converter 6. FIG. 4 is a principal block diagram of a power supply apparatus showing an example in which the FET 11 as the second power conversion means is provided in the down converter 6, and the same reference numerals as those in FIG. 1 denote the same or equivalent parts. In FIG. 4, the FET 11a is mounted on a substrate on which the elements constituting the down converter 6 are mounted. Then, a dimming signal for controlling the duty ratio of the FET 11a is supplied from the control unit 452 of the PDU 45. The process for controlling the duty ratio of the FET 11a by the dimming signal is the same as the process shown in the flowchart of FIG.

  The second power conversion means is not limited to the FET, and can be realized by using, for example, a diode. FIG. 5 is a diagram showing a third embodiment of the second power conversion means, and the same reference numerals as those in FIG. 1 denote the same or equivalent parts. In the third embodiment, the headlight 25 is grounded via a diode D 1 provided in the PDU 45 instead of the FET 11. In this example, since a voltage drop by the diode D1 can be expected to be about 1 volt, the current flowing through the headlight 25 can be reduced in accordance with this voltage drop.

  The diode D1 is not limited to being provided in the PDU 45, and can be provided in the down converter 6, for example. FIG. 6 is a principal block diagram of a power supply apparatus showing a fourth embodiment of the second power conversion means, and the same reference numerals as those in FIG. 1 denote the same or equivalent parts. In FIG. 6, a diode D <b> 2 is mounted on a substrate on which elements constituting the down converter 6 are mounted. Also in this example, as in the embodiment shown in FIG. 5, the current flowing through the headlight 25 can be reduced by the voltage drop of the diode D2.

  Next, a fifth embodiment of the second power conversion means will be described. FIG. 7 is a principal block diagram of a power supply apparatus showing a fifth embodiment of the second power conversion means, where the same reference numerals as those in FIG. 1 denote the same or equivalent parts. In FIG. 7, another down converter 6a is provided on the substrate B on which the down converter 6 is mounted. The output of the down converter 6 is always connected to the system line L3 and is connected to the input side of the down converter 6a. The down converter 6a further reduces the voltage (14.3 volts) input from the down converter 6 to a voltage (for example, 12 volts) corresponding to the rated voltage of the headlight 25 and outputs the voltage. The output of the down converter 6 a is connected to the headlight 25 and other lighting devices 27.

  As described above, according to each embodiment, since the voltage applied to the headlight 25 is reduced to the rated voltage of the headlight 25, the charging voltage of the sub battery 5 is set higher than the rated voltage of the headlight 25. Also, it can be avoided that the durability of the headlight 25 is affected.

  In the embodiment shown in FIGS. 1 and 4 to 6, the applied voltage to the headlight 25 is reduced. However, as in the embodiment shown in FIG. Similarly, the voltage or current can be reduced by the second power conversion means.

  DESCRIPTION OF SYMBOLS 1 ... Electric vehicle, 2 ... Front fork, 3 ... Body frame, 4 ... Main battery, 5 ... Sub battery, 6 ... Down converter (1st power conversion means), 6a ... 2nd down converter (2nd electric power) Conversion means), 7 ... BMU, 8 ... relay device, 9 ... main switch, 10 ... general electrical equipment, 11, 11a ... FET (second power conversion means), 14 ... auto power off relay, 15 ... throttle sensor, DESCRIPTION OF SYMBOLS 16 ... Angle sensor, 18 ... Motor, 22 ... Seat switch, 23 ... Throttle sensor, 25 ... Headlight, 27 ... Light fixture, 28 ... Side stand switch, D1, D2 ... Diode (2nd power conversion means)

Claims (8)

A high-voltage main battery (4) used in an electric vehicle (1) having a motor (18) as a drive source of the vehicle (1) and an auxiliary machine including at least a headlight (25), and the main battery A sub-battery (5) having a lower voltage than (4), the output voltage of the sub-battery (5), and the output voltage of the main battery (4) stepped down by the first power conversion means (6) In the electric vehicle power supply device configured to supply power to the auxiliary machine,
The first power conversion means (6) is configured to step down the output voltage of the main battery (4) to generate a charging voltage for the sub-battery (5),
Electric vehicle power further comprising second power conversion means (11, 11a, D1, D2, 6a) for further stepping down the output voltage of the sub-battery (5) and supplying it to the auxiliary machine Feeding device. The second power conversion means is a switching element (11, 11a) whose duty ratio is controlled so as to limit a voltage applied to the auxiliary machine,
The electric power supply apparatus for an electric vehicle according to claim 1, wherein the duty ratio is variable according to a traveling state of the vehicle (1). Vehicle speed detecting means (16) for detecting the speed of the vehicle (1),
3. The electric vehicle according to claim 2, wherein when the vehicle (1) is detected to be stopped based on the detected vehicle speed, the duty ratio is switched to a smaller value than when the vehicle (1) is traveling. Power supply equipment. The electric vehicle has a side stand (24) that makes the vehicle (1) self-supporting, and a side stand switch (28) that outputs a detection signal when the side stand (24) is in the non-storage position,
3. The electric vehicle power supply device according to claim 2, wherein when the side stand switch (28) outputs a detection signal, the duty ratio is switched to zero.   The charging voltage supplied to the sub-battery (5) by the first power conversion means (6) is higher than the rated voltage of the sub-battery (5). The electric power supply apparatus for electric vehicles in any one.   The electric power supply device for an electric vehicle according to claim 1, wherein the second power conversion means is a diode (D1, D2) having a voltage drop function. The first power conversion means (6) is a first down converter, and the second power conversion means (6a) is a second down converter that further steps down the output voltage of the first down converter. Yes,
The first down-converter (6) outputs a voltage for charging the sub-battery (5), and the second down-converter (6a) outputs a sub-battery ( 5. The electric vehicle power supply device according to claim 1, wherein the electric vehicle power supply device is connected to 5) and an auxiliary machine.   The switching element (11) is driven at a duty ratio of 100% until the first power conversion means (6) is activated when the main switch (9) is turned on. The power supply apparatus for electric vehicles as described.

Images