Transport vehicle and control method for transport vehicle

Abstract

To suppress environmental pollution at a work site.SOLUTION: A transportation vehicle includes: a dump body; a vehicle body that supports the dump body; a travel device that has drive wheels and supports the vehicle body; a trolley power reception device that is supplied with power from a trolley wire; a fuel cell that causes an electrochemical reaction between hydrogen and oxygen to generate power; and an electric motor that generates driving force for rotating the drive wheels on the basis of the power from at least one of the trolley wire and the fuel cell.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present disclosure relates to a haulage vehicle and a control method for a haulage vehicle.

Background Art

[0002] In the technical field related to haulage vehicles, a mining truck as disclosed in Patent Document 1 is known.

Prior Art Literature

Patent Literature

[0003]

Patent Literature 1

Summary of Invention

Problem to be Solved by the Invention

[0004] When an engine is used as a power source for a haulage vehicle, exhaust gas from the engine may pollute the environment of a work site.

[0005] An object of the present disclosure is to suppress pollution of the environment at a work site.

Means for Solving the Problem

[0006] According to the present disclosure, there is provided a haulage vehicle comprising: a dump body; a vehicle body that supports the dump body; a traveling device that has drive wheels and supports the vehicle body; a trolley power receiving device that receives power supply from a trolley wire; a fuel cell that generates power by causing an electrochemical reaction between hydrogen and oxygen; and an electric motor that generates a driving force for rotating the drive wheels based on electric power from at least one of the trolley wire and the fuel cell.

Effect of the Invention

[0007] According to the present disclosure, pollution of the environment at a work site is suppressed.

Brief Description of Drawings

[0008] [Figure 1] Figure 1 is a schematic diagram showing a transport vehicle according to the first embodiment. [Figure 2] Figure 2 is a diagram showing the configuration of a transport vehicle according to the first embodiment. [Figure 3] Figure 3 is a hard block diagram showing an example of an energy supply system according to the first embodiment. [Figure 4] Figure 4 is a hard block diagram showing an example of an energy supply system according to the first embodiment. [Figure 5] Figure 5 is a hard block diagram showing an example of an energy supply system according to the first embodiment. [Figure 6] Figure 6 is a hard block diagram showing an example of an energy supply system according to the first embodiment. [Figure 7] Figure 7 is a soft block diagram showing an example of a control device according to the first embodiment. [Figure 8] Figure 8 is an illustrative diagram showing an example of the operation of the energy supply system according to the first embodiment. [Figure 9] Figure 9 is a flowchart showing an example of a control method for a transport vehicle according to the first embodiment. [Figure 10] Figure 10 is a flowchart showing an example of a control method for a transport vehicle according to the first embodiment. [Figure 11] Figure 11 is a hard block diagram showing an example of an energy supply system according to the first embodiment. [Figure 12] Figure 12 is a hard block diagram showing an example of an energy supply system according to the first embodiment. [Figure 13] Figure 13 is a flowchart showing an example of a control method for a transport vehicle according to the first embodiment. [Figure 14] Figure 14 is a flowchart showing an example of a control method for a transport vehicle according to the first embodiment. [Figure 15] Figure 15 is a hard block diagram showing an example of an energy supply system according to the second embodiment. [Figure 16]FIG. 16 is a hardware block diagram showing an example of an energy supply system according to a second embodiment. [Figure 17] FIG. 17 is a hardware block diagram showing an example of an energy supply system according to the second embodiment. [Figure 18] FIG. 18 is a software block diagram showing an example of a control device according to the second embodiment. [Figure 19] FIG. 19 is an image diagram showing an example of the operation of the energy supply system according to the second embodiment. [Figure 20] FIG. 20 is a flowchart showing an example of a control method for a transport vehicle according to the second embodiment. [Figure 21] FIG. 21 is a flowchart showing an example of a control method for a transport vehicle according to the second embodiment. [Figure 22] FIG. 22 is a hardware block diagram showing an example of an energy supply system according to the second embodiment. [Figure 23] FIG. 23 is a flowchart showing an example of a control method for a transport vehicle according to the second embodiment. [Figure 24] FIG. 24 is a flowchart showing an example of a control method for a transport vehicle according to the second embodiment. [Figure 25] FIG. 25 is a hardware block diagram showing an example of an energy supply system according to a third embodiment. [Figure 26] FIG. 26 is a software block diagram showing an example of a control device according to the third embodiment. [Figure 27] FIG. 27 is an image diagram showing an example of the operation of the energy supply system according to the third embodiment. [Figure 28] FIG. 28 is a flowchart showing an example of a control method for a transport vehicle according to the third embodiment. [Figure 29] FIG. 29 is a block diagram showing a computer system according to an embodiment. DETAILED DESCRIPTION OF EMBODIMENTS

[0009] The embodiments of this disclosure will be described below with reference to the drawings, but this disclosure is not limited to these embodiments. The components of the embodiments described below can be combined as appropriate. In addition, some components may not be used.

[0010] [First Embodiment] The first embodiment will be described.

[0011] <Transport Vehicles> Figure 1 is a schematic diagram showing a transport vehicle 1 according to an embodiment. In this embodiment, the transport vehicle 1 is a dump truck that travels around a work site to transport cargo. An example of a work site for the transport vehicle 1 is a mine or a quarry. A mine refers to a place or business establishment where minerals are extracted. Examples of mines include metal mines where metals are extracted, non-metallic mines where limestone is extracted, or coal mines where coal is extracted. A quarry refers to a place or business establishment where stone materials are extracted. An example of cargo transported by the transport vehicle 1 is excavated material from the work site.

[0012] The transport vehicle 1 may be an unmanned dump truck that operates without driver operation, or a manned dump truck that operates based on driver operation. In this embodiment, the transport vehicle 1 is a manned dump truck.

[0013] The transport vehicle 1 comprises a dump body 2, a vehicle body 3, a running gear 4, a trolley power receiving device 5, a power supply pantograph 6, a fuel cell 7, a drive motor 8, a position sensor 9, and a control device 10.

[0014] The dump body 2 is the component on which the cargo is loaded. At least a portion of the dump body 2 is positioned above the vehicle body 3. The dump body 2 performs dumping and lowering operations. Dumping operation refers to the movement of tilting the dump body 2 away from the vehicle body 3 in the dumping direction. Lowering operation refers to the movement of bringing the dump body 2 closer to the vehicle body 3. When performing soil removal operations, the dump body 2 performs dumping operations.

[0015] The vehicle body 3 includes a vehicle frame. The vehicle body 3 supports the dump body 2. The vehicle body 3 is supported by the running gear 4. The trolley power receiving device 5, fuel cell 7, position sensor 9, and control device 10 are each mounted on the vehicle body 3.

[0016] The running gear 4 supports the vehicle body 3. The running gear 4 moves the transport vehicle 1. The running gear 4 moves the transport vehicle 1 forward or backward. At least a portion of the running gear 4 is positioned below the vehicle body 3. The running gear 4 has wheels 11 and tires 12.

[0017] The tire 12 is mounted on the wheel 11. The wheel 11 includes a front wheel 11F and a rear wheel 11R. The tire 12 includes a front tire 12F mounted on the front wheel 11F and a rear tire 12R mounted on the rear wheel 11R. The front wheel 11F is the steering wheel. The rear wheel 11R is the drive wheel.

[0018] The trolley power receiving device 5 is powered by the trolley wire 13. The trolley power receiving device 5 receives power supplied from the trolley wire 13. The trolley wire 13 is an overhead wire installed at the work site. The trolley power receiving device 5 receives power from the trolley wire 13 via the power supply pantograph 6. The power supply pantograph 6 is supported by a part of the dump body 2. The power supply pantograph 6 moves up and down relative to the dump body 2. When the power supply pantograph 6 rises and makes contact with the trolley wire 13, power is supplied from the trolley wire 13 to the trolley power receiving device 5. When the power supply pantograph 6 lowers and moves away from the trolley wire 13, the supply of power from the trolley wire 13 to the trolley power receiving device 5 is stopped.

[0019] The fuel cell 7 generates electricity by an electrochemical reaction between hydrogen and oxygen. An outside air inlet is provided at the front of the vehicle body 3. The fuel cell 7 generates electricity using the oxygen contained in the air introduced through the outside air inlet.

[0020] The drive motor 8 is an electric motor that generates a driving force to rotate the rear wheels 11R, which are the drive wheels. The drive motor 8 generates a driving force that rotates the rear wheels 11R based on power from at least one of the trolley wire 13 and the fuel cell 7.

[0021] The position sensor 9 detects the position of the transport vehicle 1. The position sensor 9 is located on the vehicle body 3. The position sensor 9 detects the current position of the vehicle body 3. In this embodiment, the position sensor 9 uses the Global Navigation Satellite System (GNSS) to detect the position of the transport vehicle 1. The position sensor 9 includes a GNSS receiver.

[0022] Figure 2 is a configuration diagram showing a transport vehicle 1 according to an embodiment. The transport vehicle 1 includes a monitor 54, an accelerator / brake pedal 56, a shift lever 57, a lift lever 58, a first input unit 61, a second input unit 62, an energy supply system 17, a vehicle drive system 18, and a control device 10.

[0023] The monitor 54, accelerator / brake pedal 56, shift lever 57, lift lever 58, first input unit 61, and second input unit 62 are each located in the driver's cab of the transport vehicle 1. The monitor 54 displays display data. When the driver operates the accelerator / brake pedal 56, the running gear 4 accelerates or decelerates. When the driver operates the shift lever 57, the speed gear of the running gear 4 is changed or the running gear 4 is switched between forward and reverse. When the driver operates the lift lever 58, the dump body 2 performs a dumping or lowering operation. The first input unit 61 and the second input unit 62 each generate an input signal when operated by the driver.

[0024] The energy supply system 17 includes a hydrogen tank 33, a hydrogen supply device 34, a trolley power receiving device 5, a fuel cell 7, a capacitor 35, and a voltage converter 36. The hydrogen supply device 34 supplies hydrogen from the hydrogen tank 33 to the fuel cell 7. Air is supplied to the fuel cell 7 from an outside air inlet provided on the vehicle body 3. The fuel cell 7 generates electricity by an electrochemical reaction between hydrogen and oxygen. The capacitor 35 is charged by power from at least one of the trolley wire 13 and the fuel cell 7. The voltage converter 36 converts the voltage of the fuel cell 7 or the voltage of the capacitor 35.

[0025] The vehicle drive system 18 includes an inverter 37, a pump drive motor 38, a hydraulic pump 39, a control valve 40, a hoist cylinder 41, an inverter 42, a travel drive motor 8, a reduction mechanism 43, and wheels 11. The inverter 37 converts the DC current from the voltage converter 36 into a three-phase AC current and supplies it to the pump drive motor 38. The pump drive motor 38 is an electric motor that generates the driving force to operate the hydraulic pump 39. The hydraulic fluid discharged from the hydraulic pump 39 is supplied to the hoist cylinder 41 via the control valve 40. The supply of hydraulic fluid to the hoist cylinder 41 causes the hoist cylinder 41 to operate. The hoist cylinder 41 causes the dump body 2 to perform a dumping or lowering operation. The inverter 42 converts the DC current from the voltage converter 36 into a three-phase AC current and supplies it to the travel drive motor 8. The travel drive motor 8 is an electric motor that generates the driving force to rotate the rear wheels 11R. The driving force generated by the drive motor 8 is transmitted to the rear wheels 11R via the reduction mechanism 43. The rotation of the wheels 11 causes the transport vehicle 1 to move.

[0026] The control device 10 includes an energy control unit 47, a vehicle operation control unit 48, a vehicle information storage unit 50, a terrain information storage unit 51, and a monitor control unit 53. The energy control unit 47 controls the energy supply system 17. The first input unit 61 generates a trolley power reception permission signal as an input signal when operated by the driver. The second input unit 62 generates a trolley battery charge permission signal as an input signal when operated by the driver. The vehicle operation control unit 48 controls the vehicle drive system 18. The vehicle information storage unit 50 stores information related to the transport vehicle 1 on which the vehicle information storage unit 50 is installed. The terrain information storage unit 51 stores map information of the work site. The map information of the work site includes terrain information and location information of the work site. The terrain information of the work site includes, for example, the slope angle (gradient) of the road surface of the road at the work site on which the transport vehicle 1 travels. The location information of the work site includes location information of the trolley switching section, location information of the trolley section, and location information of the FC switching section. The monitor control unit 53 controls the monitor 54.

[0027] <Energy supply system> Figure 3 is a hard block diagram showing an example of an energy supply system 17 according to an embodiment. The energy supply system 17 supplies power to the vehicle drive system 18. The energy supply system 17 supplies power to the pump drive motor 38 via inverter 37 and to the traction drive motor 8 via inverter 42. Hereinafter, for the sake of simplicity, supplying power to at least one of the pump drive motor 38 and the traction drive motor 8 will be appropriately referred to as supplying power to the vehicle drive system 18.

[0028] The energy supply system 17 includes a power supply pantograph 6, a fuel cell 7, a DC / DC converter 21, a capacitor 35, and a DC / DC converter 22. The voltage converter 36 includes the DC / DC converter 21 and the DC / DC converter 22.

[0029] The alternating current generated at the power plant 14 is converted to direct current at the DC substation 15. The DC substation 15 steps down the system voltage Vsup of the power plant 14 at a predetermined step-down ratio α. The DC substation 15 reduces the system voltage Vsup to the trolley voltage Vtry. The trolley power receiving device 5 includes a trolley power supply line 16 connected to the power supply pantograph 6. The trolley power supply line 16 is powered from the trolley wire 13. The trolley voltage Vtry is applied to the trolley power supply line 16.

[0030] The fuel cell 7 is connected to the vehicle drive system 18 via the power line 19. The battery 35 is connected to the vehicle drive system 18 via the power line 20. The trolley power supply line 16 is connected to the power line 19.

[0031] The DC / DC converter 21 converts the FC voltage Vfc, which represents the voltage of the fuel cell 7. The DC / DC converter 21 is located on the power line 19. The DC / DC converter 21 boosts the FC voltage Vfc at a predetermined boost ratio β. The DC / DC converter 21 is a unidirectional DC / DC converter that can output power only from the primary side to the secondary side. The primary side of the DC / DC converter 21 is the low voltage side. The secondary side of the DC / DC converter 21 is the high voltage side.

[0032] The trolley power supply line 16 is connected to the power line 19 between the DC / DC converter 21 and the vehicle drive system 18. That is, the trolley power supply line 16 is connected to the power line 19 on the secondary side of the DC / DC converter 21. The primary side of the DC / DC converter 21 is the fuel cell 7 side, and the secondary side of the DC / DC converter 21 is the trolley power supply line 16 side (vehicle drive system 18 side). Power is supplied from the fuel cell 7 to the vehicle drive system 18 via the DC / DC converter 21. The FC voltage Vfc converted by the DC / DC converter 21 is applied to the traction drive motor 8 of the vehicle drive system 18. Power is not supplied from the trolley power supply line 16 to the fuel cell 7 by the DC / DC converter 21.

[0033] The DC / DC converter 22 converts the battery voltage Vbat, which represents the voltage of the capacitor 35. The DC / DC converter 22 is located on the power line 20. The DC / DC converter 22 boosts the battery voltage Vbat at a predetermined boost ratio γ. The DC / DC converter 22 is a bidirectional DC / DC converter capable of outputting power from the primary side to the secondary side and from the secondary side to the primary side. The primary side of the DC / DC converter 22 is the low-voltage side. The secondary side of the DC / DC converter 22 is the high-voltage side.

[0034] Power line 20 is connected to power line 19 on the secondary side of DC / DC converter 21. Power line 20 is connected to power line 19 between the connection point between trolley power supply line 16 and power line 19 and the vehicle drive system 18. The primary side of DC / DC converter 22 is the side of the capacitor 35, and the secondary side of DC / DC converter 22 is the side of the trolley power supply line 16 (vehicle drive system 18 side). Power is supplied from capacitor 35 to the vehicle drive system 18 via DC / DC converter 22. The battery voltage Vbat converted by DC / DC converter 22 is applied to the traction motor 8 of the vehicle drive system 18. Capacitor 35 is charged by power from at least one of the trolley wire 13 and fuel cell 7.

[0035] When the step-down ratio α is small and the trolley voltage Vtry is low, the power received by the trolley power receiving device 5 is small. Therefore, the vehicle voltage Vveh, which indicates the voltage required by the vehicle drive system 18, becomes low, and the increase in cost is suppressed. For example, if the step-down ratio α is 0.27 and the trolley voltage Vtry is 27% of the system voltage Vsup, then the vehicle voltage Vveh is 27% of the system voltage Vsup. The step-up ratio β and step-up ratio γ are determined based on the vehicle voltage Vveh. When the FC voltage Vfc is 6% or more and 12% or less of the system voltage Vsup, the step-up ratio β is 2.3 or more and 4.5 or less. When the battery voltage Vbat is 13% or more and 15% or less of the system voltage Vsup, the step-up ratio β is 1.8 or more and 2.1 or less.

[0036] When the step-down ratio α is large and the trolley voltage Vtry is high, the trolley power receiving device 5 receives a large amount of power. As a result, for example, the vehicle voltage Vveh increases, and the driving output of the running device 4 improves. For example, if the step-down ratio α is 0.39 and the trolley voltage Vtry is 40% of the system voltage Vsup, then the vehicle voltage Vveh is 40% of the system voltage Vsup. The step-up ratio β and step-up ratio γ are determined based on the vehicle voltage Vveh. When the FC voltage Vfc is 6% or more and 12% or less of the system voltage Vsup, the step-up ratio β is 3.3 or more and 6.7 or less. When the battery voltage Vbat is 13% or more and 15% or less of the system voltage Vsup, the step-up ratio β is 2.7 or more and 3.1 or less.

[0037] Figure 4 is a hard block diagram showing an example of the energy supply system 17 according to the embodiment. Figure 4 is a modified example of Figure 3, showing an example in which a DC / DC converter 23 is added to the configuration shown in Figure 3.

[0038] The DC / DC converter 23 converts the trolley voltage Vtry, which represents the voltage across the trolley wire 13. The DC / DC converter 23 is located on the trolley power supply line 16. The DC / DC converter 23 steps down the trolley voltage Vtry at a predetermined step-down ratio δ. The DC / DC converter 23 is a unidirectional DC / DC converter capable of outputting power only from the primary side to the secondary side. The primary side of the DC / DC converter 23 is the high-voltage side. The secondary side of the DC / DC converter 23 is the low-voltage side.

[0039] Furthermore, the DC / DC converter 23 may be a bidirectional DC / DC converter capable of outputting power from the primary side to the secondary side, or from the secondary side to the primary side.

[0040] The primary side of the DC / DC converter 23 is the trolley wire 13 side, and the secondary side of the DC / DC converter 23 is the power line 19 side (vehicle drive system 18 side). Power is supplied from the trolley wire 13 to the vehicle drive system 18 via the DC / DC converter 23. The trolley voltage Vtry converted by the DC / DC converter 23 is applied to the traction motor 8 of the vehicle drive system 18.

[0041] The DC / DC converter 23, which steps down the trolley voltage Vtry, allows the trolley voltage Vtry to be increased even when the vehicle voltage Vveh is low. For example, if the step-down ratio α is 0.39, the trolley voltage Vtry is 40% of the system voltage Vsup, and the step-down ratio δ is 0.68, then the vehicle voltage Vveh is 27% of the system voltage Vsup. The step-up ratios β and γ are determined based on the vehicle voltage Vveh. If the FC voltage Vfc is 6% or more and 12% or less of the system voltage Vsup, the step-up ratio β is 2.3 or more and 4.5 or less. If the battery voltage Vbat is 13% or more and 15% or less of the system voltage Vsup, the step-up ratio β is 1.8 or more and 2.1 or less.

[0042] Figure 5 is a hard block diagram showing an example of an energy supply system 17 according to the embodiment. Figure 5 is a modified version of Figure 3, showing an example in which a power line 30, a first switch 25, a second switch 26, and a third switch 27 are added to the configuration shown in Figure 3. In addition, a bidirectional DC / DC converter 24 is provided instead of the DC / DC converter 21.

[0043] Power line 30 is arranged in parallel with power line 19. The first switch 25 is located on power line 19 between the fuel cell 7 and the DC / DC converter 24. The second switch 26 is located on power line 19 between the DC / DC converter 24 and the vehicle drive system 18. The second switch 26 is located on power line 19 between the connection point between the trolley power supply line 16 and power line 19 and the vehicle drive system 18. The third switch 27 is located on power line 30. One end of power line 30 is connected to power line 19 between the first switch 25 and the DC / DC converter 24. The other end of power line 30 is connected to power line 20 on the secondary side of the DC / DC converter 22. Power line 20 on the secondary side of the DC / DC converter 22 is connected to power line 19 between the second switch 26 and the vehicle drive system 18. The other end of power line 30 is connected to power line 19 between the second switch 26 and the vehicle drive system 18 via power line 20.

[0044] The DC / DC converter 24 converts the trolley voltage Vtry of the trolley wire 13 and the FC voltage Vfc of the fuel cell 7. The DC / DC converter 24 is located in the power line 19 between the first switch 25 and the second switch 26. The trolley power supply line 16 is connected to the power line 19 between the DC / DC converter 24 and the second switch 26.

[0045] The DC / DC converter 24 is a bidirectional DC / DC converter capable of outputting power from the primary side to the secondary side and from the secondary side to the primary side. The primary side of the DC / DC converter 24 is the low-voltage side. The secondary side of the DC / DC converter 24 is the high-voltage side. The primary side of the DC / DC converter 24 is the fuel cell 7 side, and the secondary side of the DC / DC converter 24 is the trolley power supply line 16 side (vehicle drive system 18 side).

[0046] The DC / DC converter 24 boosts the FC voltage Vfc at a predetermined boost ratio β. The DC / DC converter 24 also steps down the trolley voltage Vtry at a predetermined step-down ratio ε. Power is supplied to the vehicle drive system 18 from at least one of the trolley wire 13 and the fuel cell 7 via the DC / DC converter 24. At least one of the trolley voltage Vtry and FC voltage Vfc converted by the DC / DC converter 24 is applied to the traction motor 8 of the vehicle drive system 18. The capacitor 35 is charged by the power from at least one of the trolley wire 13 and the fuel cell 7.

[0047] The first switch 25, the second switch 26, and the third switch 27 constitute a switching mechanism that switches between a first state in which power is supplied to the vehicle drive system 18 from the trolley wire 13 via the DC / DC converter 24, a second state in which power is supplied to the vehicle drive system 18 from the fuel cell 7 and the capacitor 35 via the DC / DC converter 24, and a third state in which power is supplied to the vehicle drive system 18 from the capacitor 35 via the DC / DC converter 22.

[0048] The first switch 25, the second switch 26, and the third switch 27 are controlled to switch between a first state in which power is supplied to the vehicle drive system 18 from the trolley wire 13, a second state in which power is supplied to the vehicle drive system 18 from the fuel cell 7 and the capacitor 35, and a third state in which power is supplied to the vehicle drive system 18 from the capacitor 35. When power is supplied to the vehicle drive system 18, the traction motor 8 is driven.

[0049] When power is supplied to the vehicle drive system 18 from the trolley wire 13, the first switch 25 is opened, the second switch 26 is opened, and the third switch 27 is connected. Power from the trolley wire 13 is input to the DC / DC converter 24 from the secondary side of the DC / DC converter 24, stepped down at a predetermined step-down ratio ε, and then supplied to the vehicle drive system 18 via the power line 30 and the third switch 27. The traction drive motor 8 generates a driving force to rotate the rear wheels 11R based on the power from the trolley wire 13. When the capacitor 35 is charged with power from the trolley wire 13, the first switch 25 is opened, the second switch 26 is opened, and the third switch 27 is connected.

[0050] When power is supplied to the vehicle drive system 18 from the fuel cell 7 and the battery 35, the first switch 25 is connected, the second switch 26 is connected, and the third switch 27 is opened. Power from the fuel cell 7 is input to the DC / DC converter 24 from the primary side of the DC / DC converter 24 via the first switch 25, boosted at a predetermined boost ratio β, and then supplied to the vehicle drive system 18 via the second switch 26. The drive motor 8 generates a driving force that rotates the rear wheels 11R based on the power from the fuel cell 7. When the battery 35 is charged with power from the fuel cell 7, the first switch 25 is connected, the second switch 26 is connected, and the third switch 27 is opened.

[0051] When power is supplied from the capacitor 35 to the vehicle drive system 18, the first switch 25 is opened, the second switch 26 is opened, and the third switch 27 is opened. Power from the capacitor 35 is input to the DC / DC converter 22 from the primary side of the DC / DC converter 22, is boosted at a predetermined boost ratio γ, and then supplied to the vehicle drive system 18. The drive motor 8 generates a driving force to rotate the rear wheels 11R based on the power from the capacitor 35.

[0052] The DC / DC converter 24 is a shared DC / DC converter used for both the conversion of the trolley voltage Vtry and the conversion of the fuel cell voltage Vfc. Since the DC / DC converter 24 is used for both supplying power from the trolley wire 13 to the vehicle drive system 18 and supplying power from the fuel cell 7 to the vehicle drive system 18, the increase in the cost of the energy supply system 17 is suppressed. In addition, since one DC / DC converter 24 is used for both the conversion of the trolley voltage Vtry and the conversion of the fuel cell voltage Vfc, the increase in size of the energy supply system 17 is suppressed.

[0053] Figure 6 is a hard block diagram showing an example of an energy supply system 17 according to the embodiment. Figure 6 is a modified example of Figure 5, showing an example in which a diode 28 is placed in the power line 30 instead of the third switch 27 in Figure 5. When sufficient insulation resistance is ensured between the fuel cell 7 and the vehicle drive system 18, a diode 28 can be placed in the power line 30 instead of the third switch 27, as shown in Figure 6. This suppresses an increase in cost and size of the energy supply system 17.

[0054] Figure 7 is a soft block diagram showing an example of a control device 10 according to the embodiment. Figure 7 shows an example of a control device 10 that controls the energy supply system 17 shown in Figure 5.

[0055] The control device 10 includes an energy control unit 47, a vehicle operation control unit 48, a vehicle information storage unit 50, a terrain information storage unit 51, an energy switching control unit 44, and a monitor control unit 53. The energy switching control unit 44 includes an FC trolley switching unit 45 and a trolley capacitor charging unit 46.

[0056] The energy control unit 47 monitors the charge state (SOC: State of Charge) of the capacitor 35. When the capacitor 35 is fully charged, the SOC is 100%, and when the capacitor 35 is completely discharged, the SOC is 0%.

[0057] The vehicle operation control unit 48 monitors the vehicle speed, which indicates the travel speed of the running device 4.

[0058] The vehicle information storage unit 50 acquires detection data from the position sensor 9. The position sensor 9 detects the current position of the vehicle body 3. The vehicle information storage unit 50 acquires the detection data from the position sensor 9 and monitors the current position of the vehicle body 3.

[0059] The terrain information storage unit 51 stores map information of the work site. As will be described later, the work site is defined as a trolley switching section, a trolley section, and an FC switching section. In this embodiment, the map information includes location information of the trolley switching section, location information of the trolley section, and location information of the FC switching section.

[0060] The FC trolley switching unit 45 controls a switch mechanism including a first switch 25, a second switch 26, and a third switch 27 so as to switch between a first state in which power is supplied to the vehicle drive system 18 from the trolley wire 13, a second state in which power is supplied to the vehicle drive system 18 from the fuel cell 7 and the capacitor 35, and a third state in which power is supplied to the vehicle drive system 18 from the capacitor 35. The FC trolley switching unit 45 controls the switch mechanism so as to switch between the first state, the second state, and the third state based on a trolley power reception permission signal (trolley power reception permission flag) input from a first input unit 61, map information including location information of the trolley section input from a terrain information storage unit 51, the current position of the vehicle body 3 input from a vehicle information storage unit 50, a trolley power reception flag input from a vehicle information storage unit 50, the vehicle speed input from a vehicle operation control unit 48, and the charge state (SOC) of the capacitor 35 input from an energy control unit 47.

[0061] The trolley capacitor charging unit 46 controls a switch mechanism including a first switch 25, a second switch 26, and a third switch 27 so that the capacitor 35 is charged by power from the trolley wire 13. Based on the trolley battery charge permission signal (trolley battery charge permission flag) input from the second input unit 62, the trolley power receiving flag input from the vehicle information storage unit 50, and the charge state (SOC) of the capacitor 35 input from the energy control unit 47, the trolley capacitor charging unit 46 charges the capacitor 35 with power from the trolley wire 13.

[0062] The FC trolley switching unit 45 transmits a trolley power reception flag to the vehicle information storage unit 50, indicating that it has switched from FC trolley switching control to trolley power reception state. The vehicle information storage unit 50 stores the trolley power reception flag.

[0063] The monitor control unit 53 displays the trolley power reception status on the monitor 54 based on the trolley power reception flag from the vehicle information storage unit 50.

[0064] Figure 8 is an illustrative diagram showing an example of the operation of the energy supply system 17 according to this embodiment. As shown in Figure 8, the trolley wire 13 is installed on the uphill road at the work site. A trolley switching section, a trolley section, and an FC switching section are defined on the travel path at the work site. The trolley switching section is defined before the uphill road. The trolley section is defined on the uphill road. The FC switching section is defined after the uphill road.

[0065] The FC trolley switching unit 45 controls the switch mechanism so that the vehicle drive system 18 is driven based on the power output from the fuel cell 7 and the battery 35 during the FC battery driving section before the trolley switching section.

[0066] The FC trolley switching unit 45 controls the switch mechanism so that, in the trolley switching section, it switches from a second state in which power is supplied to the vehicle drive system 18 from the fuel cell 7 and the capacitor 35 to a first state in which power is supplied to the vehicle drive system 18 from the trolley wire 13. The trolley switching section is a capacitor-only driving section in which the output of power from the fuel cell 7 is stopped and the vehicle drive system 18 is driven only by power supplied from the capacitor 35.

[0067] The trolley section is a trolley-powered running section in which the vehicle drive system 18 is driven solely by power supplied from the trolley wire 13. The FC trolley switching unit 45 controls the switch mechanism so that the first state, in which power is supplied from the trolley wire 13 to the vehicle drive system 18, is maintained in the trolley section. Excess power is used to charge the battery 35.

[0068] The FC trolley switching unit 45 controls the switch mechanism so that in the FC switching section, it switches from a first state in which power is supplied to the vehicle drive system 18 from the trolley wire 13 to a second state in which power is supplied to the vehicle drive system 18 from the fuel cell 7 and the capacitor 35. The FC switching section is a capacitor-only driving section in which power reception from the trolley wire 13 is stopped and the vehicle drive system 18 is driven only by power supplied from the capacitor 35.

[0069] The FC trolley switching unit 45 controls the switch mechanism so that the vehicle drive system 18 is driven based on the power output from the fuel cell 7 and the battery 35 during the FC battery driving section after the FC switching section.

[0070] Figure 9 is a flowchart showing an example of a control method for the transport vehicle 1 according to the embodiment. Figure 9 shows a control method for the transport vehicle 1 when the transport vehicle 1 having the energy supply system 17 shown in Figure 5 is traveling on the uphill road shown in Figure 8.

[0071] When the transport vehicle 1 travels through the FC battery section, the FC trolley switching unit 45 controls the switch mechanism so that power is supplied from the fuel cell 7 to the vehicle drive system 18. The first switch 25 is connected, the second switch 26 is connected, and the third switch 27 is opened.

[0072] The FC trolley switching unit 45 determines whether the trolley power reception permission flag is ON or OFF (step SA1).

[0073] In step SA1, if it is determined that the trolley power reception permission flag is ON (step SA1: Yes), the FC trolley switching unit 45 calculates the predicted vehicle passage position based on the current position of the vehicle body 3 input from the vehicle information storage unit 50 and the vehicle speed input from the vehicle operation control unit 48 (step SA2).

[0074] The FC trolley switching unit 45 receives map information of the work site from the terrain information storage unit 51 (step SA3).

[0075] The FC trolley switching unit 45 determines whether or not the predicted vehicle passage position is within the trolley switching section (step SA4).

[0076] In step SA4, if it is determined that the predicted vehicle passage position is within the trolley switching section (step SA4: Yes), the FC trolley switching unit 45 calculates the State of Charge (SOC) of the capacitor 35 (step SA5).

[0077] The FC trolley switching unit 45 determines whether the State of Charge (SOC) of the capacitor 35 calculated in step SA5 is equal to or greater than a predetermined threshold (step SA6).

[0078] In step SA6, if it is determined that the State of Charge (SOC) of the storage device 35 is above a threshold (step SA6: Yes), the FC trolley switching unit 45 stops the output of power from the fuel cell 7 (step SA7).

[0079] The FC trolley switching unit 45 opens the first switch 25 (step SA8).

[0080] The FC trolley switching unit 45 adjusts the voltage on the low-voltage side (primary side) of the DC / DC converter 24 (step SA9).

[0081] The FC trolley switching unit 45 determines whether the difference between the low-voltage side voltage of the DC / DC converter 24 and the high-voltage side (secondary side) voltage of the DC / DC converter 22 has become smaller than a predetermined specified value (step SA10).

[0082] In step SA10, if it is determined that the difference between the low-voltage side voltage of the DC / DC converter 24 and the high-voltage side voltage of the DC / DC converter 22 is not smaller than a specified value (step SA10: No), the FC trolley switching unit 45 returns to the process of step SA9.

[0083] In step SA10, if it is determined that the difference between the low-voltage side voltage of the DC / DC converter 24 and the high-voltage side voltage of the DC / DC converter 22 has become smaller than the specified value (step SA10: Yes), the FC trolley switching unit 45 connects the third switch 27 (step SA11).

[0084] The FC trolley switching unit 45 opens the second switch 26 (step SA12).

[0085] The FC trolley switching unit 45 adjusts the voltage on the high-voltage side (secondary side) of the DC / DC converter 24 (step SA13).

[0086] The FC trolley switching unit 45 determines whether the difference between the high-voltage side voltage of the DC / DC converter 24 and the trolley voltage Vtry has become smaller than a predetermined specified value (step SA14).

[0087] In step SA14, if it is determined that the difference between the high-voltage side voltage of the DC / DC converter 24 and the trolley voltage Vtry is not smaller than the specified value (step SA14: No), the FC trolley switching unit 45 returns to the process of step SA13.

[0088] In step SA14, if it is determined that the difference between the high-voltage side voltage of the DC / DC converter 24 and the trolley voltage Vtry has become smaller than the specified value (step SA14: Yes), the FC trolley switching unit 45 raises the power supply pantograph 6 (step SA15).

[0089] The FC trolley switching unit 45 determines that it has started receiving power from the trolley wire 13 and turns on the trolley power receiving flag (step SA16).

[0090] In step SA4, if it is determined that the predicted vehicle passage position is not within the trolley switching section (step SA4: No), the FC trolley switching unit 45 determines whether the predicted vehicle passage position is outside the FC switching section or the trolley section (step SA17).

[0091] In step SA17, if it is determined that the predicted vehicle passage position is outside the FC switching section or the trolley section (step SA17: Yes), or in step SA1, if it is determined that the trolley power reception permission flag is not ON (step SA1: No), the FC trolley switching unit 45 determines whether or not the trolley power reception flag is ON (step SA18).

[0092] In step SA18, if it is determined that the trolley power receiving flag is ON (step SA18: Yes), the FC trolley switching unit 45 lowers the power supply pantograph 6 (step SA19).

[0093] The FC trolley switching unit 45 adjusts the voltage on the high-voltage side of the DC / DC converter 24 (step SA20).

[0094] The FC trolley switching unit 45 determines whether the difference between the high-voltage side voltage of the DC / DC converter 24 and the high-voltage side voltage of the DC / DC converter 22 has become smaller than a predetermined value (step SA21).

[0095] In step SA21, if it is determined that the difference between the high-voltage side voltage of the DC / DC converter 24 and the high-voltage side voltage of the DC / DC converter 22 is not smaller than a specified value (step SA21: No), the FC trolley switching unit 45 returns to the process of step SA20.

[0096] In step SA21, if it is determined that the difference between the high-voltage side voltage of the DC / DC converter 24 and the high-voltage side voltage of the DC / DC converter 22 has become smaller than the specified value (step SA21: Yes), the FC trolley switching unit 45 connects the second switch 26 (step SA22).

[0097] The FC trolley switching unit 45 opens the third switch 27 (step SA23).

[0098] The FC trolley switching unit 45 adjusts the voltage on the low-voltage side (primary side) of the DC / DC converter 24 (step SA24).

[0099] The FC trolley switching unit 45 determines whether the difference between the low-voltage side voltage of the DC / DC converter 24 and the FC voltage Vfc has become smaller than a predetermined specified value (step SA25).

[0100] In step SA25, if it is determined that the difference between the low-voltage side voltage of the DC / DC converter 24 and the FC voltage Vfc is not smaller than the specified value (step SA25: No), the FC trolley switching unit 45 returns to the process of step SA24.

[0101] In step SA25, if it is determined that the difference between the low-voltage side voltage of the DC / DC converter 24 and the FC voltage Vfc has become smaller than the specified value (step SA25: Yes), the FC trolley switching unit 45 connects the first switch 25 (step SA26).

[0102] The FC trolley switching unit 45 initiates the output of power from the fuel cell 7 (step SA27).

[0103] The FC trolley switching unit 45 determines that it has stopped receiving power from the trolley wire 13 and turns the trolley power receiving flag OFF (step SA28).

[0104] The process ends when the processing in step SA16 is completed, when it is determined in step SA6 that the SOC of the capacitor 35 is not above a threshold (step SA6: No), when it is determined in step SA17 that the predicted vehicle passage position is not outside the FC switching section or the trolley section (step SA17: No), when it is determined in step SA18 that the trolley power receiving flag is OFF (step SA18: No), or when the processing in step SA28 is completed.

[0105] Figure 10 is a flowchart showing an example of a control method for the transport vehicle 1 according to the embodiment. Figure 10 shows a control method for the transport vehicle 1 when the transport vehicle 1 having the energy supply system 17 shown in Figure 5 is charging the battery 35.

[0106] The trolley capacitor charging unit 46 determines whether the trolley battery charging permission flag is ON or OFF (step SB1).

[0107] If, in step SB1, it is determined that the trolley battery charging permission flag is ON (step SB1: Yes), the trolley capacitor charging unit 46 determines whether the trolley power receiving flag is ON or not (step SB2).

[0108] In step SB2, if it is determined that the trolley power receiving flag is ON (step SB2: Yes), the trolley capacitor charging unit 46 calculates the State of Charge (SOC) of the capacitor 35 (step SB3).

[0109] The trolley capacitor charging unit 46 determines whether the State of Charge (SOC) of the capacitor 35 calculated in step SB3 is below a predetermined threshold (step SB4).

[0110] In step SB4, if it is determined that the State of Charge (SOC) of the capacitor 35 is below the threshold (step SB4: Yes), the trolley capacitor charging unit 46 adjusts the voltage and current on the low-voltage side (primary side) of the DC / DC converter 22 to charge the capacitor 35 (step SB5), and then returns to the process in step SB2.

[0111] In step SB1, if it is determined that the trolley battery charge permission flag is OFF (step SB1: No), in step SB2, if it is determined that the trolley power receiving flag is OFF (step SB2: No), and in step SB4, if it is determined that the State of Charge (SOC) of the capacitor 35 exceeds the threshold (step SB4: No), the trolley capacitor charging unit 46 adjusts the voltage and current on the primary side of the DC / DC converter 22 to stop charging the capacitor 35 (step SB6), and terminates the process.

[0112] Figure 11 is a hard block diagram showing an example of an energy supply system 17 according to the embodiment. Figure 11 is a modified example of Figure 5, showing an example in which the DC / DC converter 22 is omitted from the configuration shown in Figure 5. By omitting the DC / DC converter 22, the increase in cost and size of the energy supply system 17 is suppressed.

[0113] Figure 12 is a hard block diagram showing an example of an energy supply system 17 according to the embodiment. Figure 12 is a modification of Figure 11, showing an example in which a diode 28 is placed in the power line 30 instead of the third switch 27 in Figure 11. When sufficient insulation resistance is ensured between the fuel cell 7 and the vehicle drive system 18, a diode 28 can be placed in the power line 30 instead of the third switch 27, as shown in Figure 12. This suppresses an increase in cost and size of the energy supply system 17.

[0114] Figure 13 is a flowchart showing an example of a control method for the transport vehicle 1 according to the embodiment. Figure 13 shows a control method for the transport vehicle 1 when the transport vehicle 1 having the energy supply system 17 shown in Figure 11 is traveling on the uphill road shown in Figure 8.

[0115] When the transport vehicle 1 travels through the FC battery section, the FC trolley switching unit 45 controls the switch mechanism so that power is supplied from the fuel cell 7 to the vehicle drive system 18. The first switch 25 is connected, the second switch 26 is connected, and the third switch 27 is opened.

[0116] The FC trolley switching unit 45 determines whether the trolley power reception permission flag is ON or OFF (step SC1).

[0117] In step SC1, if it is determined that the trolley power reception permission flag is ON (step SC1: Yes), the FC trolley switching unit 45 calculates the predicted vehicle passage position based on the current position of the vehicle body 3 input from the vehicle information storage unit 50 and the vehicle speed input from the vehicle operation control unit 48 (step SC2).

[0118] The FC trolley switching unit 45 receives map information of the work site from the terrain information storage unit 51 (step SC3).

[0119] The FC trolley switching unit 45 determines whether or not the predicted vehicle passage position is within the trolley switching section (step SC4).

[0120] In step SAC, if it is determined that the predicted vehicle passage position is within the trolley switching section (step SC4: Yes), the FC trolley switching unit 45 calculates the State of Charge (SOC) of the capacitor 35 (step SC5).

[0121] The FC trolley switching unit 45 determines whether the State of Charge (SOC) of the capacitor 35 calculated in step SC5 is equal to or greater than a predetermined threshold (step SC6).

[0122] In step SC6, if it is determined that the State of Charge (SOC) of the storage device 35 is above a threshold (step SC6: Yes), the FC trolley switching unit 45 stops the output of power from the fuel cell 7 (step SC7).

[0123] The FC trolley switching unit 45 opens the first switch 25 (step SC8).

[0124] The FC trolley switching unit 45 adjusts the voltage on the low-voltage side (primary side) of the DC / DC converter 24 (step SC9).

[0125] The FC trolley switching unit 45 determines whether the difference between the low-voltage side voltage of the DC / DC converter 24 and the battery voltage Vbat of the capacitor 35 has become smaller than a predetermined specified value (step SC10).

[0126] In step SA10, if it is determined that the difference between the low-voltage side voltage of the DC / DC converter 24 and the battery voltage Vbat of the capacitor 35 is not smaller than the specified value (step SC10: No), the FC trolley switching unit 45 returns to the process of step SC9.

[0127] In step SC10, if it is determined that the difference between the low-voltage side voltage of the DC / DC converter 24 and the battery voltage Vbat of the capacitor 35 has become smaller than the specified value (step SC10: Yes), the FC trolley switching unit 45 connects the third switch 27 (step SC11).

[0128] The FC trolley switching unit 45 opens the second switch 26 (step SC12).

[0129] The FC trolley switching unit 45 adjusts the voltage on the high-voltage side (secondary side) of the DC / DC converter 24 (step SC13).

[0130] The FC trolley switching unit 45 determines whether the difference between the high-voltage side voltage of the DC / DC converter 24 and the trolley voltage Vtry has become smaller than a predetermined specified value (step SC14).

[0131] In step SC14, if it is determined that the difference between the high-voltage side voltage of the DC / DC converter 24 and the trolley voltage Vtry is not smaller than the specified value (step SC14: No), the FC trolley switching unit 45 returns to the process of step SC13.

[0132] In step SC14, if it is determined that the difference between the high-voltage side voltage of the DC / DC converter 24 and the trolley voltage Vtry has become smaller than the specified value (step SC14: Yes), the FC trolley switching unit 45 raises the power supply pantograph 6 (step SC15).

[0133] The FC trolley switching unit 45 determines that it has started receiving power from the trolley wire 13 and turns on the trolley power receiving flag (step SC16).

[0134] In step SC4, if it is determined that the predicted vehicle passage position is not within the trolley switching section (step SC4: No), the FC trolley switching unit 45 determines whether the predicted vehicle passage position is outside the FC switching section or the trolley section (step SC17).

[0135] If, in step SC17, it is determined that the predicted vehicle passage position is outside the FC switching section or the trolley section (step SC17: Yes), or if, in step SC1, it is determined that the trolley power reception permission flag is not ON (step SC1: No), the FC trolley switching unit 45 determines whether or not the trolley power reception flag is ON (step SC18).

[0136] In step SC18, if it is determined that the trolley power receiving flag is ON (step SC18: Yes), the FC trolley switching unit 45 lowers the power supply pantograph 6 (step SC19).

[0137] The FC trolley switching unit 45 adjusts the voltage on the high-voltage side of the DC / DC converter 24 (step SC20).

[0138] The FC trolley switching unit 45 determines whether the difference between the high-voltage side voltage of the DC / DC converter 24 and the battery voltage Vbat of the capacitor 35 has become smaller than a predetermined value (step SC21).

[0139] In step SC21, if it is determined that the difference between the high-voltage side voltage of the DC / DC converter 24 and the battery voltage Vbat of the capacitor 35 is not smaller than the specified value (step SC21: No), the FC trolley switching unit 45 returns to the process of step SC20.

[0140] In step SC21, if it is determined that the difference between the high-voltage side voltage of the DC / DC converter 24 and the battery voltage Vbat of the capacitor 35 has become smaller than the specified value (step SC21: Yes), the FC trolley switching unit 45 connects the second switch 26 (step SC22).

[0141] The FC trolley switching unit 45 opens the third switch 27 (step SC23).

[0142] The FC trolley switching unit 45 adjusts the voltage on the low-voltage side (primary side) of the DC / DC converter 24 (step SC24).

[0143] The FC trolley switching unit 45 determines whether the difference between the low-voltage side voltage of the DC / DC converter 24 and the FC voltage Vfc has become smaller than a predetermined specified value (step SC25).

[0144] In step SC25, if it is determined that the difference between the low-voltage side voltage of the DC / DC converter 24 and the FC voltage Vfc is not smaller than the specified value (step SC25: No), the FC trolley switching unit 45 returns to the process of step SC24.

[0145] In step SC25, if it is determined that the difference between the low-voltage side voltage of the DC / DC converter 24 and the FC voltage Vfc has become smaller than the specified value (step SC25: Yes), the FC trolley switching unit 45 connects the first switch 25 (step SC26).

[0146] The FC trolley switching unit 45 initiates the output of power from the fuel cell 7 (step SC27).

[0147] The FC trolley switching unit 45 determines that it has stopped receiving power from the trolley wire 13 and turns the trolley power receiving flag OFF (step SC28).

[0148] The process ends when the processing in step SC16 is completed, when it is determined in step SC6 that the SOC of the capacitor 35 is not above a threshold (step SC6: No), when it is determined in step SC17 that the predicted vehicle passage position is not outside the FC switching section or the trolley section (step SC17: No), when it is determined in step SC18 that the trolley power receiving flag is OFF (step SC18: No), or when the processing in step SC28 is completed.

[0149] Figure 14 is a flowchart showing an example of a control method for the transport vehicle 1 according to the embodiment. Figure 14 shows a control method for the transport vehicle 1 when the transport vehicle 1 having the energy supply system 17 shown in Figure 11 is charging the battery 35.

[0150] The trolley capacitor charging unit 46 determines whether the trolley battery charging permission flag is ON or OFF (step SD1).

[0151] If, in step SD1, it is determined that the trolley battery charging permission flag is ON (step SD1: Yes), the trolley capacitor charging unit 46 determines whether the trolley power receiving flag is ON or not (step SD2).

[0152] In step SD2, if it is determined that the trolley power receiving flag is ON (step SD2: Yes), the trolley capacitor charging unit 46 calculates the State of Charge (SOC) of the capacitor 35 (step SD3).

[0153] The trolley capacitor charging unit 46 determines whether the State of Charge (SOC) of the capacitor 35 calculated in step SD3 is below a predetermined threshold (step SD4).

[0154] In step SD4, if it is determined that the State of Charge (SOC) of the capacitor 35 is below the threshold (step SD4: Yes), the trolley capacitor charging unit 46 adjusts the voltage and current on the low-voltage side (primary side) of the DC / DC converter 24 to charge the capacitor 35 (step SD5), and then returns to the process in step SD2.

[0155] In step SD1, if it is determined that the trolley battery charge permission flag is OFF (step SD1: No), in step SD2, if it is determined that the trolley power receiving flag is OFF (step SD2: No), and in step SD4, if it is determined that the State of Charge (SOC) of the capacitor 35 exceeds the threshold (step SD4: No), the trolley capacitor charging unit 46 adjusts the voltage and current on the primary side of the DC / DC converter 24 to stop charging the capacitor 35 (step SD6), and terminates the process.

[0156] <Effects> As described above, according to the embodiment, power is supplied to the transport vehicle 1 from the trolley wire 13. In addition, the fuel cell 7 of the transport vehicle 1 generates electricity. Power is supplied to the drive motor 8 of the transport vehicle 1 from at least one of the trolley wire 13 and the fuel cell 7. The drive motor 8 generates a driving force that rotates the rear wheels 11R based on the power from at least one of the trolley wire 13 and the fuel cell 7. The transport vehicle 1 moves using the driving force generated by the drive motor 8. Since no exhaust gas is emitted from the transport vehicle 1, environmental pollution at the work site is suppressed.

[0157] As explained with reference to Figure 5, etc., a DC / DC converter 24 capable of converting both the trolley voltage Vtry of the trolley wire 13 and the FC voltage Vfc of the fuel cell 7 is provided. Since one DC / DC converter 24 is used for both the conversion of the trolley voltage Vtry and the FC voltage Vfc, the increase in cost and size of the energy supply system 17 is suppressed.

[0158] When the transport vehicle 1 travels uphill, the drive motor 8 is driven based on power from the trolley wire 13. High-output external power supply on uphill roads enables high-speed travel and improves productivity. In addition, using trolley power in high-load trolley sections reduces the hydrogen consumption of the fuel cell 7.

[0159] The surplus power from the trolley wire 13 is used to charge the battery 35. By driving the traction motor 8 based on the power from the battery 35, the hydrogen consumption of the fuel cell 7 can be reduced even when traveling on a track other than the trolley section.

[0160] [Second Embodiment] A second embodiment will now be described. In the following description, components that are the same as or equivalent to those in the above-described embodiment will be denoted by the same reference numerals, and the descriptions of those components will be simplified or omitted.

[0161] <Energy supply system> Figure 15 is a hard block diagram showing an example of an energy supply system 17 according to an embodiment. Figure 15 is a modified version of Figure 3, in which a capacity-type capacitor 29 is placed in place of the fuel cell 7 shown in Figure 3, and an output-type capacitor 35B is placed in place of the capacitor 35.

[0162] The capacity-type capacitor 29 can output power for a longer period of time than the output-type capacitor 35B. The energy density [Wh / kg] of the capacity-type capacitor 29 is higher than that of the output-type capacitor 35B. The output-type capacitor 35B has a higher output than the capacity-type capacitor 29. The power density [kW / kg] of the output-type capacitor 35B is higher than that of the capacity-type capacitor 29. The capacity-type capacitor 29 is an example of the first type of capacitor. The output-type capacitor 35B is an example of the second type of capacitor.

[0163] The transport vehicle 1 has a charging port 31. The charging port 31 is connected to a capacitive capacitor 29. An external charger is connected to the charging port 31. The external charger is connected to a power plant 14 or a DC substation 15 via a transmission line separate from the trolley wire 13. The external charger is a separate charger from the trolley wire 13. The capacitive capacitor 29 is charged by the external charger via the charging port 31.

[0164] The traction motor 8 of the vehicle drive system 18 generates a driving force that rotates the rear wheels 11R based on power from at least one of the trolley wire 13 and the capacitive capacitor 29.

[0165] The output-type capacitor 35B is charged by power from at least one of the trolley wire 13 and the capacity-type capacitor 29. The traction motor 8 can generate a driving force to rotate the rear wheels 11R based on the power from the output-type capacitor 35B.

[0166] The DC / DC converter 21 converts the battery voltage Vbat1, which represents the voltage of the capacitive capacitor 29. The DC / DC converter 21 boosts the battery voltage Vbat1 at a predetermined boost ratio β. The DC / DC converter 22 is a unidirectional DC / DC converter capable of outputting power only from the primary side to the secondary side. The primary side of the DC / DC converter 21 is the low-voltage side. The secondary side of the DC / DC converter 21 is the high-voltage side. The primary side of the DC / DC converter 21 is the capacitive capacitor 29 side, and the secondary side of the DC / DC converter 21 is the trolley power supply line 16 side (vehicle drive system 18 side). Power is supplied from the capacitive capacitor 29 to the vehicle drive system 18 via the DC / DC converter 21. The battery voltage Vbat1 converted by the DC / DC converter 21 is applied to the traction motor 8 of the vehicle drive system 18. Power is not supplied from the trolley power supply line 16 to the capacitive capacitor 29 by the DC / DC converter 21.

[0167] The DC / DC converter 22 converts the battery voltage Vbat2, which represents the voltage of the output type capacitor 35B. The DC / DC converter 22 boosts the battery voltage Vbat2 at a predetermined boost ratio γ. The DC / DC converter 22 is a bidirectional DC / DC converter capable of outputting power from the primary side to the secondary side and from the secondary side to the primary side. The primary side of the DC / DC converter 22 is the low voltage side. The secondary side of the DC / DC converter 22 is the high voltage side. The primary side of the DC / DC converter 22 is the output type capacitor 35B side, and the secondary side of the DC / DC converter 22 is the trolley power supply line 16 side (vehicle drive system 18 side). Power is supplied from the output type capacitor 35B to the vehicle drive system 18 via the DC / DC converter 22. The battery voltage Vbat2 converted by the DC / DC converter 22 is applied to the traction motor 8 of the vehicle drive system 18. Furthermore, the output-type capacitor 35B is charged by power from at least one of the trolley wire 13 and the capacity-type capacitor 29.

[0168] Figure 16 is a hard block diagram showing an example of an energy supply system 17 according to the embodiment. Figure 16 is a modified version of Figure 15, showing an example in which a DC / DC converter 23 is added to the configuration shown in Figure 15.

[0169] The DC / DC converter 23 converts the trolley voltage Vtry, which represents the voltage across the trolley wire 13. The DC / DC converter 23 is located on the trolley power supply line 16. The DC / DC converter 23 steps down the trolley voltage Vtry at a predetermined step-down ratio δ. The DC / DC converter 23 is a unidirectional DC / DC converter capable of outputting power only from the primary side to the secondary side. The primary side of the DC / DC converter 23 is the high-voltage side. The secondary side of the DC / DC converter 23 is the low-voltage side.

[0170] The primary side of the DC / DC converter 23 is the trolley wire 13 side, and the secondary side of the DC / DC converter 23 is the power line 19 side (vehicle drive system 18 side). Power is supplied from the trolley wire 13 to the vehicle drive system 18 via the DC / DC converter 23. The trolley voltage Vtry converted by the DC / DC converter 23 is applied to the traction motor 8 of the vehicle drive system 18.

[0171] The DC / DC converter 23, which steps down the trolley voltage Vtry, makes it possible to increase the trolley voltage Vtry even when the vehicle voltage Vveh is low.

[0172] Figure 17 is a hard block diagram showing an example of an energy supply system 17 according to the embodiment. Figure 17 is a modified version of Figure 15, showing an example in which a power line 30, a diode 32, a first switch 26B, and a second switch 27B are added to the configuration shown in Figure 15. In addition, a bidirectional DC / DC converter 24 is provided instead of the DC / DC converter 21.

[0173] Power line 30 is arranged in parallel with power line 19. Diode 32 is located on power line 19 between capacitive capacitor 29 and DC / DC converter 24. First switch 26B is located on power line 19 between DC / DC converter 24 and vehicle drive system 18. First switch 26B is located on power line 19 between the connection point between trolley power supply line 16 and power line 19 and vehicle drive system 18. Second switch 27B is located on power line 30. One end of power line 30 is connected to power line 19 between diode 32 and DC / DC converter 24. The other end of power line 30 is connected to power line 20 on the secondary side of DC / DC converter 22. Power line 20 on the secondary side of DC / DC converter 22 is connected to power line 19 between first switch 26B and vehicle drive system 18. The other end of power line 30 is connected to power line 19 between first switch 26B and vehicle drive system 18 via power line 20.

[0174] The DC / DC converter 24 converts the trolley voltage Vtry of the trolley wire 13 and the battery voltage Vbat1 of the capacitive capacitor 29. The DC / DC converter 24 is located in the power line 19 between the diode 32 and the first switch 26B. The trolley power supply line 16 is connected to the power line 19 between the DC / DC converter 24 and the first switch 26B.

[0175] The DC / DC converter 24 is a bidirectional DC / DC converter capable of outputting power from the primary side to the secondary side and from the secondary side to the primary side. The primary side of the DC / DC converter 24 is the low-voltage side. The secondary side of the DC / DC converter 24 is the high-voltage side. The primary side of the DC / DC converter 24 is the capacitive capacitor 29 side, and the secondary side of the DC / DC converter 24 is the trolley power supply line 16 side (vehicle drive system 18 side).

[0176] The DC / DC converter 24 boosts the battery voltage Vbat1 at a predetermined boost ratio β. The DC / DC converter 24 also steps down the trolley voltage Vtry at a predetermined step-down ratio ε. Power is supplied to the vehicle drive system 18 from at least one of the trolley wire 13 and the capacitive capacitor 29 via the DC / DC converter 24. At least one of the trolley voltage Vtry and battery voltage Vbat1 converted by the DC / DC converter 24 is applied to the traction motor 8 of the vehicle drive system 18. The output capacitor 35B is charged by the power from at least one of the trolley wire 13 and the capacitive capacitor 29.

[0177] The first switch 26B and the second switch 27B constitute a switching mechanism that switches between a first state in which power is supplied to the vehicle drive system 18 from the trolley wire 13 via the DC / DC converter 24, a second state in which power is supplied to the vehicle drive system 18 from the capacitive capacitor 29 via the DC / DC converter 24, and a third state in which power is supplied to the vehicle drive system 18 from the output capacitor 35B via the DC / DC converter 22.

[0178] By controlling the first switch 26B and the second switch 27B, the vehicle drive system 18 is switched between a first state in which power is supplied from the trolley wire 13, a second state in which power is supplied from the capacitive capacitor 29, and a third state in which power is supplied from the output capacitor 35B. When power is supplied to the vehicle drive system 18, the traction motor 8 is driven.

[0179] When power is supplied from the trolley wire 13 to the vehicle drive system 18, the first switch 26B is opened and the second switch 27B is connected. Power from the trolley wire 13 is input to the DC / DC converter 24 from the secondary side of the DC / DC converter 24, stepped down at a predetermined step-down ratio ε, and then supplied to the vehicle drive system 18 via the power line 30 and the second switch 27B. The traction drive motor 8 generates a driving force to rotate the rear wheels 11R based on the power from the trolley wire 13. When the output type capacitor 35B is charged with power from the trolley wire 13, the first switch 26B is also opened and the second switch 27B is connected.

[0180] When power is supplied from the capacitive-type capacitor 29 to the vehicle drive system 18, the first switch 26B is connected and the second switch 27B is opened. Power from the capacitive-type capacitor 29 is input to the DC / DC converter 24 from the primary side of the DC / DC converter 24 via the diode 32, boosted at a predetermined boost ratio β, and then supplied to the vehicle drive system 18 via the first switch 26B. The drive motor 8 generates a driving force to rotate the rear wheels 11R based on the power from the capacitive-type capacitor 29. When the output-type capacitor 35B is charged with power from the capacitive-type capacitor 29, the first switch 26B is connected and the second switch 27B is opened.

[0181] When power is supplied from the output-type capacitor 35B to the vehicle drive system 18, the first switch 26B is opened and the second switch 27B is opened. Power from the output-type capacitor 35B is input to the DC / DC converter 22 from the primary side, boosted at a predetermined boost ratio γ, and then supplied to the vehicle drive system 18. The drive motor 8 generates a driving force to rotate the rear wheels 11R based on the power from the output-type capacitor 35B.

[0182] The DC / DC converter 24 is a shared DC / DC converter used for both the conversion of the trolley voltage Vtry and the conversion of the battery voltage Vbat1. Since the DC / DC converter 24 is used for both supplying power from the trolley wire 13 to the vehicle drive system 18 and supplying power from the capacitive capacitor 29 to the vehicle drive system 18, the increase in the cost of the energy supply system 17 is suppressed. In addition, since one DC / DC converter 24 is used for both the conversion of the trolley voltage Vtry and the conversion of the battery voltage Vbat1, the size of the energy supply system 17 is suppressed.

[0183] Figure 18 is a soft block diagram showing an example of a control device 10 according to the embodiment. Figure 18 shows an example of a control device 10 that controls the energy supply system 17 shown in Figure 5.

[0184] The control device 10 includes an energy control unit 47, a vehicle operation control unit 48, a vehicle information storage unit 50, a terrain information storage unit 51, an energy switching control unit 44B, and a monitor control unit 53. The energy switching control unit 44B includes a capacitor trolley switching unit 45B and a trolley capacitor charging unit 46.

[0185] The energy control unit 47 monitors the charge state (SOC: State of Charge) of the output type capacitor 35B. When the output type capacitor 35B is fully charged, the SOC is 100%, and when the output type capacitor 35B is completely discharged, the SOC is 0%.

[0186] The vehicle operation control unit 48 monitors the vehicle speed, which indicates the travel speed of the running device 4.

[0187] The vehicle information storage unit 50 acquires detection data from the position sensor 9. The position sensor 9 detects the current position of the vehicle body 3. The vehicle information storage unit 50 acquires the detection data from the position sensor 9 and monitors the current position of the vehicle body 3.

[0188] The terrain information storage unit 51 stores map information of the work site. As will be described later, the work site is defined as a trolley switching section, a trolley section, and a capacitor switching section. In this embodiment, the map information includes location information of the trolley switching section, location information of the trolley section, and location information of the capacitor switching section.

[0189] The capacitor trolley switching unit 45B controls a switching mechanism including the first switch 26B and the second switch 27B so as to switch between a first state in which power is supplied to the vehicle drive system 18 from the trolley wire 13, a second state in which power is supplied to the vehicle drive system 18 from the capacity type capacitor 29, and a third state in which power is supplied to the vehicle drive system 18 from the output type capacitor 35B. The capacitor trolley switching unit 45B controls the switch mechanism to switch between a first state, a second state, and a third state based on the trolley power reception permission signal (trolley power reception permission flag) input from the first input unit 61, map information including location information of the trolley section input from the terrain information storage unit 51, the current position of the vehicle body 3 input from the vehicle information storage unit 50, the trolley power reception flag input from the vehicle information storage unit 50, the vehicle speed input from the vehicle operation control unit 48, and the charge state (SOC) of the output type capacitor 35B input from the energy control unit 47.

[0190] The trolley capacitor charging unit 46 controls a switch mechanism including the first switch 26B and the second switch 27B so that the output capacitor 35B is charged by power from the trolley wire 13. Based on the trolley battery charge permission signal (trolley battery charge permission flag) input from the second input unit 62, the trolley power receiving flag input from the vehicle information storage unit 50, and the charge state (SOC) of the output capacitor 35B input from the energy control unit 47, the trolley capacitor charging unit 46 charges the output capacitor 35B with power from the trolley wire 13.

[0191] The capacitor trolley switching unit 45B transmits a trolley power reception flag to the vehicle information storage unit 50, indicating that it has switched from capacitor trolley switching control to trolley power reception state. The vehicle information storage unit 50 stores the trolley power reception flag.

[0192] The monitor control unit 53 displays the trolley power reception status on the monitor 54 based on the trolley power reception flag from the vehicle information storage unit 50.

[0193] Figure 19 is an illustrative diagram showing an example of the operation of the energy supply system 17 according to this embodiment. As shown in Figure 19, the trolley wire 13 is installed on the uphill road at the work site. A trolley switching section, a trolley section, and a capacitor switching section are defined on the travel path at the work site. The trolley switching section is defined before the uphill road. The trolley section is defined on the uphill road. The capacitor switching section is defined after the uphill road.

[0194] The capacitor trolley switching unit 45B controls the switch mechanism so that the vehicle drive system 18 is driven based on the power output from the capacity-type capacitor 29 and the output-type capacitor 35B in the capacity-type output-type capacitor running section before the trolley switching section.

[0195] The capacitor trolley switching unit 45B controls the switch mechanism so that, in the trolley switching section, it switches from a second state in which power is supplied from the capacitive capacitor 29 to the vehicle drive system 18 to a first state in which power is supplied from the trolley wire 13 to the vehicle drive system 18. The trolley switching section is a section in which the output of power from the capacitive capacitor 29 is stopped, and the vehicle drive system 18 is driven only by power supplied from the output capacitor 35B.

[0196] The trolley section is a trolley-powered running section in which the vehicle drive system 18 is driven solely by power supplied from the trolley wire 13. The capacitor trolley switching unit 45B controls the switch mechanism so that the first state, in which power is supplied from the trolley wire 13 to the vehicle drive system 18, is maintained in the trolley section. Surplus power is used to charge the output type capacitor 35B.

[0197] The capacitor trolley switching unit 45B controls the switch mechanism so that, in the capacitor switching section, it switches from a first state in which power is supplied to the vehicle drive system 18 from the trolley wire 13 to a second state in which power is supplied to the vehicle drive system 18 from the capacitive capacitor 29. The capacitor switching section is an output-type capacitor-only running section in which power reception from the trolley wire 13 is stopped and the vehicle drive system 18 is driven only by power supplied from the output-type capacitor 35B.

[0198] The capacitor trolley switching unit 45B controls the switch mechanism so that the vehicle drive system 18 is driven based on the power output from the capacity-type capacitor 29 and the output-type capacitor 35B during the capacity-type output-type capacitor running section after the capacitor switching section.

[0199] Figure 20 is a flowchart showing an example of a control method for the transport vehicle 1 according to the embodiment. Figure 20 shows a control method for the transport vehicle 1 when the transport vehicle 1 having the energy supply system 17 shown in Figure 17 is traveling on the uphill road shown in Figure 19.

[0200] When the transport vehicle 1 travels through the section where the capacity-type output-type capacitor is driven, the capacitor trolley switching unit 45B controls the switch mechanism so that power is supplied from the capacity-type capacitor 29 to the vehicle drive system 18. The first switch 26B is connected and the second switch 27B is opened.

[0201] The capacitor trolley switching unit 45B determines whether the trolley power reception permission flag is ON or OFF (step SE1).

[0202] In step SE1, if it is determined that the trolley power reception permission flag is ON (step SE1: Yes), the capacitor trolley switching unit 45B calculates the predicted vehicle passage position based on the current position of the vehicle body 3 input from the vehicle information storage unit 50 and the vehicle speed input from the vehicle operation control unit 48 (step SE2).

[0203] The capacitor trolley switching unit 45B receives map information of the work site from the terrain information storage unit 51 (step SE3).

[0204] The capacitor trolley switching unit 45B determines whether or not the predicted vehicle passage position is within the trolley switching section (step SE4).

[0205] In step SE4, if it is determined that the predicted vehicle passage position is within the trolley switching section (step SE4: Yes), the capacitor trolley switching unit 45B calculates the SOC of the output type capacitor 35B (step SE5).

[0206] The capacitor trolley switching unit 45B determines whether the State of Charge (SOC) of the output capacitor 35B, calculated in step SE5, is equal to or greater than a predetermined threshold (step SE6).

[0207] In step SE6, if it is determined that the SOC of the output type capacitor 35B is above the threshold (step SE6: Yes), the capacitor trolley switching unit 45B adjusts the voltage on the low-voltage side (primary side) of the DC / DC converter 24 (step SE7).

[0208] The capacitor trolley switching unit 45B determines whether the difference between the voltage on the low-voltage side of the DC / DC converter 24 and the voltage on the high-voltage side (secondary side) of the DC / DC converter 22 has become smaller than a predetermined value (step SE8).

[0209] In step SE8, if it is determined that the difference between the low-voltage side voltage of the DC / DC converter 24 and the high-voltage side voltage of the DC / DC converter 22 is not smaller than the specified value (step SE8: No), the capacitor trolley switching unit 45B returns to the process of step SE7.

[0210] In step SE8, if it is determined that the difference between the low-voltage side voltage of the DC / DC converter 24 and the high-voltage side voltage of the DC / DC converter 22 has become smaller than the specified value (step SE8: Yes), the capacitor trolley switching unit 45B opens the first switch 26B (step SE9).

[0211] The capacitor trolley switching unit 45B is connected to the second switch 27B (step SE10).

[0212] The capacitor trolley switching unit 45B adjusts the voltage on the high-voltage side (secondary side) of the DC / DC converter 24 (step SE11).

[0213] The capacitor trolley switching unit 45B determines whether the difference between the high-voltage side voltage of the DC / DC converter 24 and the trolley voltage Vtry has become smaller than a predetermined specified value (step SE12).

[0214] In step SE12, if it is determined that the difference between the high-voltage side voltage of the DC / DC converter 24 and the trolley voltage Vtry is not smaller than the specified value (step SE12: No), the capacitor trolley switching unit 45B returns to the process of step SE11.

[0215] In step SE12, if it is determined that the difference between the high-voltage side voltage of the DC / DC converter 24 and the trolley voltage Vtry has become smaller than the specified value (step SE12: Yes), the capacitor trolley switching unit 45B raises the power supply pantograph 6 (step SE13).

[0216] The capacitor trolley switching unit 45B determines that it has started receiving power from the trolley wire 13 and turns on the trolley power receiving flag (step SE14).

[0217] In step SE4, if it is determined that the predicted vehicle passage position is not within the trolley switching section (step SE4: No), the capacitor trolley switching unit 45B determines whether the predicted vehicle passage position is outside the capacitor switching section or the trolley section (step SE15).

[0218] If, in step SE15, it is determined that the predicted vehicle passage position is outside the capacitor switching section or the trolley section (step SE15: Yes), or if, in step SE1, it is determined that the trolley power reception permission flag is not ON (step SE1: No), the capacitor trolley switching unit 45B determines whether or not the trolley power reception flag is ON (step SE16).

[0219] In step SE16, if it is determined that the trolley power receiving flag is ON (step SE16: Yes), the capacitor trolley switching unit 45B lowers the power supply pantograph 6 (step SE17).

[0220] The capacitor trolley switching unit 45B adjusts the voltage on the high-voltage side of the DC / DC converter 24 (step SE18).

[0221] The capacitor trolley switching unit 45B determines whether the difference between the high-voltage side voltage of the DC / DC converter 24 and the high-voltage side voltage of the DC / DC converter 22 has become smaller than a predetermined value (step SE19).

[0222] In step SE19, if it is determined that the difference between the high-voltage side voltage of DC / DC converter 24 and the high-voltage side voltage of DC / DC converter 22 is not smaller than the specified value (step SE19: No), the capacitor trolley switching unit 45B returns to the process of step SE18.

[0223] In step SE18, if it is determined that the difference between the high-voltage side voltage of the DC / DC converter 24 and the high-voltage side voltage of the DC / DC converter 22 has become smaller than the specified value (step SE18: Yes), the capacitor trolley switching unit 45B connects the first switch 26B (step SE20).

[0224] The capacitor trolley switching unit 45B opens the second switch 27B (step SE21).

[0225] The capacitor trolley switching unit 45B adjusts the voltage on the low-voltage side (primary side) of the DC / DC converter 24 (step SE22).

[0226] The capacitor trolley switching unit 45B determines whether the difference between the low-voltage side voltage of the DC / DC converter 24 and the battery voltage Vbat1 has become smaller than a predetermined specified value (step SE23).

[0227] In step SE23, if it is determined that the difference between the low-voltage side voltage of the DC / DC converter 24 and the battery voltage Vbat1 is not smaller than the specified value (step SE23: No), the capacitor trolley switching unit 45B returns to the process of step SE22.

[0228] In step SE23, if it is determined that the difference between the low-voltage side voltage of the DC / DC converter 24 and the battery voltage Vbat1 has become smaller than the specified value (step SE23: Yes), it is determined that power reception from the trolley wire 13 has stopped, and the trolley power reception flag is turned OFF (step SE24).

[0229] The process ends when the processing in step SE14 is completed, when it is determined in step SE6 that the SOC of the output type capacitor 35B is not above a threshold (step SE6: No), when it is determined in step SE15 that the predicted vehicle passage position is not outside the capacitor switching section or the trolley section (step SE15: No), when it is determined in step SE16 that the trolley power receiving flag is OFF (step SE16: No), and when the processing in step SE24 is completed.

[0230] Figure 21 is a flowchart showing an example of a control method for the transport vehicle 1 according to the embodiment. Figure 21 shows a control method for the transport vehicle 1 when the transport vehicle 1 having the energy supply system 17 shown in Figure 17 is charging the output type capacitor 35B.

[0231] The trolley capacitor charging unit 46 determines whether the trolley battery charging permission flag is ON or OFF (step SF1).

[0232] If, in step SF1, the trolley battery charging permission flag is determined to be ON (step SF1: Yes), the trolley capacitor charging unit 46 determines whether the trolley power receiving flag is ON or not (step SF2).

[0233] In step SF2, if it is determined that the trolley power receiving flag is ON (step SF2: Yes), the trolley capacitor charging unit 46 calculates the SOC of the output capacitor 35B (step SF3).

[0234] The trolley capacitor charging unit 46 determines whether the State of Charge (SOC) of the output capacitor 35B, calculated in step SF3, is below a predetermined threshold (step SF4).

[0235] In step SF4, if it is determined that the State of Charge (SOC) of the output capacitor 35B is below the threshold (step SF4: Yes), the trolley capacitor charging unit 46 adjusts the voltage and current on the low-voltage side (primary side) of the DC / DC converter 22 to charge the output capacitor 35B (step SF5), and then returns to the process in step SF2.

[0236] In step SF1, if it is determined that the trolley battery charge permission flag is OFF (step SF1: No), in step SF2, if it is determined that the trolley power receiving flag is OFF (step SF2: No), and in step SF4, if it is determined that the SOC of the output type capacitor 35B exceeds the threshold (step SF4: No), the trolley capacitor charging unit 46 adjusts the voltage and current on the primary side of the DC / DC converter 22 to stop charging the output type capacitor 35B (step SF6), and terminates the process.

[0237] Figure 22 is a hard block diagram showing an example of an energy supply system 17 according to the embodiment. Figure 22 is a modified example of Figure 17, showing an example in which the DC / DC converter 22 is omitted from the configuration shown in Figure 17. By omitting the DC / DC converter 22, the increase in cost and size of the energy supply system 17 is suppressed.

[0238] Figure 23 is a flowchart showing an example of a control method for the transport vehicle 1 according to the embodiment. Figure 23 shows a control method for the transport vehicle 1 when the transport vehicle 1 having the energy supply system 17 shown in Figure 22 is traveling on the uphill road shown in Figure 19.

[0239] When the transport vehicle 1 travels through the section where the capacity-type output-type capacitor is driven, the capacitor trolley switching unit 45B controls the switch mechanism so that power is supplied from the capacity-type capacitor 29 to the vehicle drive system 18. The first switch 26B is connected and the second switch 27B is opened.

[0240] The capacitor trolley switching unit 45B determines whether the trolley power reception permission flag is ON or OFF (step SG1).

[0241] In step SG1, if it is determined that the trolley power reception permission flag is ON (step SG1: Yes), the capacitor trolley switching unit 45B calculates the predicted vehicle passing position based on the current position of the vehicle body 3 input from the vehicle information storage unit 50 and the vehicle speed input from the vehicle operation control unit 48 (step SG2).

[0242] The capacitor trolley switching unit 45B receives map information of the work site from the terrain information storage unit 51 (step SG3).

[0243] The capacitor trolley switching unit 45B determines whether or not the predicted vehicle passage position is within the trolley switching section (step SG4).

[0244] In step SG4, if it is determined that the predicted vehicle passage position is within the trolley switching section (step SG4: Yes), the capacitor trolley switching unit 45B calculates the SOC of the output type capacitor 35B (step SG5).

[0245] The capacitor trolley switching unit 45B determines whether the State of Charge (SOC) of the output capacitor 35B, calculated in step SG5, is equal to or greater than a predetermined threshold (step SG6).

[0246] In step SG6, if it is determined that the SOC of the output type capacitor 35B is above the threshold (step SG6: Yes), the capacitor trolley switching unit 45B adjusts the voltage on the low-voltage side (primary side) of the DC / DC converter 24 (step SG7).

[0247] The capacitor trolley switching unit 45B determines whether the difference between the low-voltage side voltage of the DC / DC converter 24 and the battery voltage Vbat of the output capacitor 35B has become smaller than a predetermined value (step SG8).

[0248] In step SG8, ​​if it is determined that the difference between the low-voltage side voltage of the DC / DC converter 24 and the battery voltage Vbat of the output type capacitor 35B is not smaller than the specified value (step SG8: No), the capacitor trolley switching unit 45B returns to the process of step SG7.

[0249] In step SG8, ​​if it is determined that the difference between the low-voltage side voltage of the DC / DC converter 24 and the battery voltage Vbat of the output type capacitor 35B has become smaller than the specified value (step SG8: Yes), the capacitor trolley switching unit 45B opens the first switch 26B (step SG9).

[0250] The capacitor trolley switching unit 45B is connected to the second switch 27B (step SG10).

[0251] The capacitor trolley switching unit 45B adjusts the voltage on the high-voltage side (secondary side) of the DC / DC converter 24 (step SG11).

[0252] The capacitor trolley switching unit 45B determines whether the difference between the high-voltage side voltage of the DC / DC converter 24 and the trolley voltage Vtry has become smaller than a predetermined specified value (step SG12).

[0253] In step SG12, if it is determined that the difference between the high-voltage side voltage of the DC / DC converter 24 and the trolley voltage Vtry is not smaller than the specified value (step SG12: No), the capacitor trolley switching unit 45B returns to the process of step SG11.

[0254] In step SG12, if it is determined that the difference between the high-voltage side voltage of the DC / DC converter 24 and the trolley voltage Vtry has become smaller than the specified value (step SG12: Yes), the capacitor trolley switching unit 45B raises the power supply pantograph 6 (step SG13).

[0255] The capacitor trolley switching unit 45B determines that it has started receiving power from the trolley wire 13 and turns on the trolley power receiving flag (step SG14).

[0256] In step SG4, if it is determined that the predicted vehicle passage position is not within the trolley switching section (step SG4: No), the capacitor trolley switching unit 45B determines whether the predicted vehicle passage position is outside the capacitor switching section or the trolley section (step SG15).

[0257] If, in step SG15, it is determined that the predicted vehicle passage position is outside the capacitor switching section or the trolley section (step SG15: Yes), or if, in step SG1, it is determined that the trolley power reception permission flag is not ON (step SG1: No), the capacitor trolley switching unit 45B determines whether or not the trolley power reception flag is ON (step SG16).

[0258] In step SG16, if it is determined that the trolley power receiving flag is ON (step SG16: Yes), the capacitor trolley switching unit 45B lowers the power supply pantograph 6 (step SG17).

[0259] The capacitor trolley switching unit 45B adjusts the voltage on the high-voltage side of the DC / DC converter 24 (step SG18).

[0260] The capacitor trolley switching unit 45B determines whether the difference between the high-voltage side voltage of the DC / DC converter 24 and the battery voltage Vbat of the output capacitor 35B has become smaller than a predetermined specified value (step SG19).

[0261] In step SG19, if it is determined that the difference between the high-voltage side voltage of the DC / DC converter 24 and the battery voltage Vbat of the output type capacitor 35B is not smaller than the specified value (step SG19: No), the capacitor trolley switching unit 45B returns to the process of step SG18.

[0262] In step SG19, if it is determined that the difference between the high-voltage side voltage of the DC / DC converter 24 and the battery voltage Vbat of the output type capacitor 35B has become smaller than the specified value (step SG19: Yes), the capacitor trolley switching unit 45B connects the first switch 26B (step SG20).

[0263] The capacitor trolley switching unit 45B opens the second switch 27B (step SG21).

[0264] The capacitor trolley switching unit 45B adjusts the voltage on the low-voltage side (primary side) of the DC / DC converter 24 (step SG22).

[0265] The capacitor trolley switching unit 45B determines whether the difference between the low-voltage side voltage of the DC / DC converter 24 and the battery voltage Vbat1 has become smaller than a predetermined specified value (step SG23).

[0266] In step SG23, if it is determined that the difference between the low-voltage side voltage of the DC / DC converter 24 and the battery voltage Vbat1 is not smaller than the specified value (step SG23: No), the capacitor trolley switching unit 45B returns to the process of step SG22.

[0267] In step SG23, if it is determined that the difference between the low-voltage side voltage of the DC / DC converter 24 and the battery voltage Vbat1 has become smaller than the specified value (step SG23: Yes), the capacitor trolley switching unit 45B determines that it has stopped receiving power from the trolley wire 13 and turns the trolley power receiving flag OFF (step SG24).

[0268] If the processing of step SG14 is completed, if it is determined in step SG6 that the SOC of output capacitor 35B is not equal to or higher than the threshold (step SG6: No), if it is determined in step SG15 that the predicted vehicle passing position is not outside the capacitor switching section or the trolley section (step SG15: No), if it is determined in step SG16 that the trolley power reception flag is OFF (step SG16: No), and if the processing of step SG24 is completed, the processing ends.

[0269] Figure 24 is a flowchart showing an example of a control method for the transport vehicle 1 according to the embodiment. Figure 24 shows a control method for the transport vehicle 1 when the transport vehicle 1 including the energy supply system 17 shown in Figure 17 charges the output capacitor 35B.

[0270] A trolley capacitor charging unit 46 determines whether a trolley battery charging permission flag is ON (step SH1).

[0271] If it is determined in step SH1 that the trolley battery charging permission flag is ON (step SH1: Yes), the trolley capacitor charging unit 46 determines whether the trolley power reception flag is ON (step SH2).

[0272] If it is determined in step SH2 that the trolley power reception flag is ON (step SH2: Yes), the trolley capacitor charging unit 46 calculates the SOC of the output capacitor 35B (step SH3).

[0273] The trolley capacitor charging unit 46 determines whether the SOC of the output capacitor 35B calculated in step SH3 is equal to or lower than a predetermined threshold (step SH4).

[0274] If it is determined in step SH4 that the SOC of the output capacitor 35B is equal to or lower than the threshold (step SH4: Yes), the trolley capacitor charging unit 46 adjusts the voltage and current on the low-voltage side (primary side) of the DC / DC converter 24 to charge the output capacitor 35B (step SH5), and then the process returns to step SH2.

[0275] In step SH1, if it is determined that the trolley battery charge permission flag is OFF (step SH1: No), in step SH2, if it is determined that the trolley power receiving flag is OFF (step SH2: No), and in step SH4, if it is determined that the SOC of the output type capacitor 35B exceeds the threshold (step SH4: No), the trolley capacitor charging unit 46 adjusts the voltage and current on the primary side of the DC / DC converter 24 to stop charging the output type capacitor 35B (step SH6), and terminates the process.

[0276] <Effects> As described above, according to the embodiment, power is supplied to the transport vehicle 1 from the trolley wire 13. Also, the capacitive capacitor 29 of the transport vehicle 1 is charged. Power is supplied to the drive motor 8 of the transport vehicle 1 from at least one of the trolley wire 13 and the capacitive capacitor 29. The drive motor 8 generates a driving force that rotates the rear wheels 11R based on the power from at least one of the trolley wire 13 and the capacitive capacitor 29. The transport vehicle 1 moves using the driving force generated by the drive motor 8. Since no exhaust gas is emitted from the transport vehicle 1, pollution of the work site environment is suppressed.

[0277] As explained with reference to Figure 17, etc., a DC / DC converter 24 capable of converting both the trolley voltage Vtry of the trolley wire 13 and the battery voltage Vbat1 of the capacitive capacitor 29 is provided. Since one DC / DC converter 24 is used for both the conversion of the trolley voltage Vtry and the battery voltage Vbat1, the increase in cost and size of the energy supply system 17 is suppressed.

[0278] When the transport vehicle 1 travels uphill, the drive motor 8 is driven based on power from the trolley wire 13. High-output external power supply on uphill roads enables high-speed travel and improves productivity. In addition, using trolley power in high-load trolley sections reduces the power consumption of the high-capacity battery 29.

[0279] The surplus power from the trolley wire 13 is used to charge the output-type capacitor 35B. By driving the traction motor 8 based on the power from the output-type capacitor 35B, the power consumption of the capacity-type capacitor 29 can be reduced even when traveling on a track separate from the trolley section.

[0280] [Third Embodiment] A third embodiment will now be described. In the following description, components that are the same as or equivalent to those in the above-described embodiment will be denoted by the same reference numerals, and the descriptions of those components will be simplified or omitted.

[0281] <Energy supply system> Figure 25 is a hard block diagram showing an example of an energy supply system 17 according to an embodiment.

[0282] The energy supply system 17 includes a trolley power supply line 16, a power line 19, a power line 30, a capacitor 29B, a DC / DC converter 24, a first switch 25, a second switch 26, and a third switch 27.

[0283] Power line 30 is arranged in parallel with power line 19. The first switch 25 is located on power line 19 between the capacitor 29B and the DC / DC converter 24. The second switch 26 is located on power line 19 between the DC / DC converter 24 and the vehicle drive system 18. The second switch 26 is located on power line 19 between the connection point between the trolley power supply line 16 and power line 19 and the vehicle drive system 18. The third switch 27 is located on power line 30. One end of power line 30 is connected to power line 19 between the first switch 25 and the DC / DC converter 24. The other end of power line 30 is connected to power line 19 between the second switch 26 and the vehicle drive system 18. The other end of power line 30 is connected to power line 19 between the second switch 26 and the vehicle drive system 18 via power line 20.

[0284] The DC / DC converter 24 converts the trolley voltage Vtry of the trolley wire 13 and the battery voltage Vbat1 of the capacitor 29B. The DC / DC converter 24 is located in the power line 19 between the first switch 25 and the second switch 26. The trolley power supply line 16 is connected to the power line 19 between the DC / DC converter 24 and the second switch 26.

[0285] The DC / DC converter 24 is a bidirectional DC / DC converter capable of outputting power from the primary side to the secondary side and from the secondary side to the primary side. The primary side of the DC / DC converter 24 is the low-voltage side. The secondary side of the DC / DC converter 24 is the high-voltage side. The primary side of the DC / DC converter 24 is the capacitor 29B side, and the secondary side of the DC / DC converter 24 is the trolley power supply line 16 side (vehicle drive system 18 side).

[0286] The DC / DC converter 24 boosts the battery voltage Vbat1 at a predetermined boost ratio β. The DC / DC converter 24 also steps down the trolley voltage Vtry at a predetermined step-down ratio ε. Power is supplied to the vehicle drive system 18 from at least one of the trolley wire 13 and the capacitor 29B via the DC / DC converter 24. At least one of the trolley voltage Vtry and battery voltage Vbat1 converted by the DC / DC converter 24 is applied to the traction motor 8 of the vehicle drive system 18.

[0287] The first switch 25, the second switch 26, and the third switch 27 constitute a switching mechanism that switches between a first state in which power is supplied to the vehicle drive system 18 from the trolley wire 13 via the DC / DC converter 24, and a second state in which power is supplied to the vehicle drive system 18 from the capacitor 29B via the DC / DC converter 24.

[0288] The first switch 25, the second switch 26, and the third switch 27 are controlled to switch between a first state in which power is supplied to the vehicle drive system 18 from the trolley wire 13, and a second state in which power is supplied to the vehicle drive system 18 from the capacitor 29B. When power is supplied to the vehicle drive system 18, the traction motor 8 is driven.

[0289] When power is supplied from the trolley wire to the vehicle drive system 18, the first switch 25 is opened, the second switch 26 is opened, and the third switch 27 is connected. Power from the trolley wire 13 is input to the DC / DC converter 24 from the secondary side of the DC / DC converter 24, stepped down at a predetermined step-down ratio ε, and then supplied to the vehicle drive system 18 via the power line 30 and the third switch 27. The travel drive motor 8 generates a driving force for rotating the rear wheels 11R based on the power from the trolley wire 13.

[0290] When power is supplied from the capacitor 29B to the vehicle drive system 18, the first switch 25 is connected, the second switch 26 is connected, and the third switch 27 is opened. Power from the capacitor 29B is input to the DC / DC converter 24 from the primary side of the DC / DC converter 24 via the first switch 25, stepped up at a predetermined step-up ratio β, and then supplied to the vehicle drive system 18 via the second switch 26. The travel drive motor 8 generates a driving force for rotating the rear wheels 11R based on the power from the capacitor 29B.

[0291] With the first switch 25 connected, the second switch 26 opened, and the third switch 27 opened, the capacitor 29B is charged by power supplied from the trolley wire 13 via the DC / DC converter 24.

[0292] The DC / DC converter 24 is a common DC / DC converter shared for converting the trolley voltage Vtry and converting the battery voltage Vbat1. Since the DC / DC converter 24 is shared both for supplying power from the trolley wire 13 to the vehicle drive system 18 and for supplying power from the capacitor 29B to the vehicle drive system 18, an increase in the cost of the energy supply system 17 is suppressed. Furthermore, since one DC / DC converter 24 is shared for converting the trolley voltage Vtry and converting the battery voltage Vbat1, an increase in the size of the energy supply system 17 is suppressed.

[0293] FIG. 26 is a software block diagram showing an example of the control device 10 according to the embodiment.

[0294] The control device 10 includes an energy control unit 47, a vehicle operation control unit 48, a vehicle information storage unit 50, a terrain information storage unit 51, an energy switching control unit 44C, and a monitor control unit 53. The energy switching control unit 44C includes a capacitor trolley switching unit 45C.

[0295] The vehicle operation control unit 48 monitors the vehicle speed, which indicates the travel speed of the running device 4.

[0296] The vehicle information storage unit 50 acquires detection data from the position sensor 9. The position sensor 9 detects the current position of the vehicle body 3. The vehicle information storage unit 50 acquires the detection data from the position sensor 9 and monitors the current position of the vehicle body 3.

[0297] The terrain information storage unit 51 stores map information of the work site. As will be described later, the work site is defined as a trolley switching section, a trolley section, and a capacitor switching section. In this embodiment, the map information includes location information of the trolley switching section, location information of the trolley section, and location information of the capacitor switching section.

[0298] The capacitor trolley switching unit 45C controls a switch mechanism including a first switch 25, a second switch 26, and a third switch 27 so as to switch between a first state in which power is supplied to the vehicle drive system 18 from the trolley wire 13 and a second state in which power is supplied to the vehicle drive system 18 from the capacitor 29B. The capacitor trolley switching unit 45C controls the switch mechanism so as to switch between the first state and the second state based on a trolley power reception permission signal (trolley power reception permission flag) input from a first input unit 61, map information including location information of the trolley section input from a terrain information storage unit 51, the current position of the vehicle body 3 input from a vehicle information storage unit 50, a trolley power reception flag input from a vehicle information storage unit 50, and the vehicle speed input from a vehicle operation control unit 48.

[0299] The capacitor trolley switching unit 45C transmits a trolley power reception flag to the vehicle information storage unit 50, indicating that it has switched from capacitor trolley switching control to trolley power reception state. The vehicle information storage unit 50 stores the trolley power reception flag.

[0300] The monitor control unit 53 displays the trolley power reception status on the monitor 54 based on the trolley power reception flag from the vehicle information storage unit 50.

[0301] Figure 27 is an illustrative diagram showing an example of the operation of the energy supply system 17 according to this embodiment. As shown in Figure 27, the trolley wire 13 is installed on the uphill road at the work site. A trolley switching section, a trolley section, and a capacitor switching section are defined on the road at the work site. The trolley switching section is defined before the uphill road. The trolley section is defined on the uphill road. The capacitor switching section is defined after the uphill road.

[0302] The capacitor trolley switching unit 45C controls the switch mechanism so that the vehicle drive system 18 is driven based on the power output from the capacitor 29B during the capacitor running section before the trolley switching section.

[0303] The capacitor trolley switching unit 45C controls the switch mechanism so that, in the trolley switching section, it switches from a second state in which power is supplied from the capacitor 29B to the vehicle drive system 18, to a first state in which power is supplied from the trolley wire 13 to the vehicle drive system 18. The trolley switching section is a coasting section in which the output of power from the capacitor 29B is stopped and the transport vehicle 1 travels by inertia.

[0304] The trolley section is a trolley-powered running section in which the vehicle drive system 18 is driven solely by power supplied from the trolley wire 13. The capacitor trolley switching unit 45C controls the switch mechanism so that the first state, in which power is supplied from the trolley wire 13 to the vehicle drive system 18, is maintained in the trolley section.

[0305] The capacitor trolley switching unit 45C controls the switch mechanism so that, in the capacitor switching section, it switches from a first state in which power is supplied to the vehicle drive system 18 from the trolley wire 13 to a second state in which power is supplied to the vehicle drive system 18 from the capacitor 29B. The capacitor switching section is a coasting section in which power reception from the trolley wire 13 is stopped and the transport vehicle 1 travels by inertia.

[0306] The capacitor trolley switching unit 45C controls the switch mechanism so that the vehicle drive system 18 is driven based on the power output from the capacitor 29B during the capacitor running section after the capacitor switching section.

[0307] Figure 28 is a flowchart showing an example of a control method for the transport vehicle 1 according to the embodiment. Figure 28 shows a control method for the transport vehicle 1 when the transport vehicle 1 having the energy supply system 17 shown in Figure 25 is traveling on the uphill road shown in Figure 27.

[0308] When the transport vehicle 1 travels through the capacitor travel section, the capacitor trolley switching unit 45C controls the switch mechanism so that power is supplied from the capacitor 29B to the vehicle drive system 18. The first switch 25 is connected, the second switch 26 is connected, and the third switch 27 is opened.

[0309] The capacitor trolley switching unit 45C determines whether the trolley power reception permission flag is ON or OFF (step SJ1).

[0310] In step SJ1, if it is determined that the trolley power reception permission flag is ON (step SJ1: Yes), the capacitor trolley switching unit 45C calculates the predicted vehicle passing position based on the current position of the vehicle body 3 input from the vehicle information storage unit 50 and the vehicle speed input from the vehicle operation control unit 48 (step SJ2).

[0311] The capacitor trolley switching unit 45C receives map information of the work site from the terrain information storage unit 51 (step SJ3).

[0312] The capacitor trolley switching unit 45C determines whether or not the predicted vehicle passage position is within the trolley switching section (step SJ4).

[0313] In step SJ4, if it is determined that the predicted vehicle passage position is within the trolley switching section (step SJ4: Yes), the capacitor trolley switching unit 45C calculates the possible coasting distance based on the vehicle speed (step SJ5).

[0314] The capacitor trolley switching unit 45C determines whether the coasting distance calculated in step SJ5 is equal to or greater than a predetermined threshold (step SJ6).

[0315] In step SJ6, if it is determined that the coasting distance is greater than or equal to a threshold (step SJ6: Yes), the capacitor trolley switching unit 45C stops the output of power from the capacitor 29B (step SJ7).

[0316] The capacitor trolley switching unit 45C opens the first switch 25 (step SJ8).

[0317] The capacitor trolley switching unit 45C adjusts the voltage on the low-voltage side (primary side) of the DC / DC converter 24 (step SJ9).

[0318] The capacitor trolley switching unit 45C determines whether the difference between the low-voltage side voltage of the DC / DC converter 24 and the vehicle voltage Vveh of the inverters 37 and 42 has become smaller than a predetermined specified value (step SJ10).

[0319] In step SJ10, if it is determined that the difference between the low-voltage side voltage of the DC / DC converter 24 and the vehicle voltage Vveh is not smaller than the specified value (step SJ10: No), the capacitor trolley switching unit 45C returns to the process of step SJ9.

[0320] In step SJ10, if it is determined that the difference between the low-voltage side voltage of the DC / DC converter 24 and the vehicle voltage Vveh has become smaller than the specified value (step SJ10: Yes), the capacitor trolley switching unit 45C connects the third switch 27 (step SJ11).

[0321] The capacitor trolley switching section 45C opens the second switch 26 (step SJ12).

[0322] The capacitor trolley switching unit 45C adjusts the voltage on the high-voltage side (secondary side) of the DC / DC converter 24 (step SJ13).

[0323] The capacitor trolley switching unit 45C determines whether the difference between the high-voltage side voltage of the DC / DC converter 24 and the trolley voltage Vtry has become smaller than a predetermined specified value (step SJ14).

[0324] In step SJ14, if it is determined that the difference between the high-voltage side voltage of the DC / DC converter 24 and the trolley voltage Vtry is not smaller than the specified value (step SJ14: No), the capacitor trolley switching unit 45C returns to the process in step SJ13.

[0325] In step SJ14, if it is determined that the difference between the high-voltage side voltage of the DC / DC converter 24 and the trolley voltage Vtry has become smaller than the specified value (step SJ14: Yes), the capacitor trolley switching unit 45C raises the power supply pantograph 6 (step SJ15).

[0326] The capacitor trolley switching unit 45C determines that it has started receiving power from the trolley wire 13 and turns on the trolley power receiving flag (step SJ16).

[0327] In step SJ4, if it is determined that the predicted vehicle passage position is not within the trolley switching section (step SJ4: No), the capacitor trolley switching unit 45C determines whether the predicted vehicle passage position is outside the capacitor switching section or the trolley section (step SJ17).

[0328] In step SJ17, if it is determined that the predicted vehicle passage position is outside the capacitor switching section or the trolley section (step SJ17: Yes), or in step SJ1, if it is determined that the trolley power reception permission flag is not ON (step SJ1: No), the capacitor trolley switching unit 45C determines whether or not the trolley power reception flag is ON (step SJ18).

[0329] In step SJ18, if it is determined that the trolley power receiving flag is ON (step SJ18: Yes), the capacitor trolley switching unit 45C lowers the power supply pantograph 6 (step SJ19).

[0330] The capacitor trolley switching unit 45C adjusts the voltage on the high-voltage side of the DC / DC converter 24 (step SJ20).

[0331] The capacitor trolley switching unit 45C determines whether the difference between the high-voltage side voltage of the DC / DC converter 24 and the vehicle voltage Vveh has become smaller than a predetermined specified value (step SJ21).

[0332] In step SJ21, if it is determined that the difference between the high-voltage side voltage of the DC / DC converter 24 and the vehicle voltage Vveh is not smaller than the specified value (step SJ21: No), the capacitor trolley switching unit 45C returns to the process of step SJ20.

[0333] In step SJ21, if it is determined that the difference between the high-voltage side voltage of the DC / DC converter 24 and the vehicle voltage Vveh has become smaller than the specified value (step SJ21: Yes), the capacitor trolley switching unit 45C connects the second switch 26 (step SJ22).

[0334] The capacitor trolley switching section 45C opens the third switch 27 (step SJ23).

[0335] The capacitor trolley switching section 45C adjusts the voltage on the low-voltage side (primary side) of the DC / DC converter 24 (step SJ24).

[0336] The capacitor trolley switching unit 45C determines whether the difference between the low-voltage side voltage of the DC / DC converter 24 and the battery voltage Vbat1 has become smaller than a predetermined specified value (step SJ25).

[0337] In step SJ25, if it is determined that the difference between the low-voltage side voltage of the DC / DC converter 24 and the battery voltage Vbat1 is not smaller than the specified value (step SJ25: No), the capacitor trolley switching unit 45C returns to the process of step SJ24.

[0338] In step SJ25, if it is determined that the difference between the low-voltage side voltage of the DC / DC converter 24 and the battery voltage Vbat1 has become smaller than the specified value (step SJ25: Yes), the capacitor trolley switching unit 45C connects the first switch 25 (step SJ26).

[0339] The capacitor trolley switching unit 45C initiates the output of power from the capacitor 29B (step SJ27).

[0340] The capacitor trolley switching unit 45C determines that it has stopped receiving power from the trolley wire 13 and turns the trolley power receiving flag OFF (step SJ28).

[0341] The process ends when the processing in step SJ16 is completed, when it is determined in step SJ6 that the coasting distance is not greater than or equal to a threshold (step SJ6: No), when it is determined in step SJ17 that the predicted vehicle passage position is not outside the capacitor switching section or the trolley section (step SJ17: No), when it is determined in step SJ18 that the trolley power receiving flag is OFF (step SJ18: No), or when the processing in step SJ28 is completed.

[0342] <Effects> As described above, according to this embodiment, power is supplied to the transport vehicle 1 from the trolley wire 13. In addition, the capacitor 29B of the transport vehicle 1 is charged by the power supplied from the trolley wire 13 via the DC / DC converter 24. A first state in which power is supplied from the trolley wire 13 to the drive motor 8 of the transport vehicle 1 via the DC / DC converter 24 is switched between and a second state in which power is supplied from the capacitor 29B to the drive motor via the DC / DC converter 24. The drive motor 8 generates a driving force that rotates the rear wheels 11R based on the power from at least one of the trolley wire 13 and the capacitor 29B. The transport vehicle 1 moves using the driving force generated by the drive motor 8. Since no exhaust gas is emitted from the transport vehicle 1, pollution of the work site environment is suppressed.

[0343] [Computer System] Figure 29 is a block diagram showing a computer system 1000 according to an embodiment. The control device 10 described above includes the computer system 1000. The computer system 1000 has a processor 1001 such as a CPU (Central Processing Unit), a main memory 1002 including non-volatile memory such as ROM (Read Only Memory) and volatile memory such as RAM (Random Access Memory), a storage 1003, and an interface 1004 including input / output circuits. The functions of the control device 10 described above are stored in the storage 1003 as a computer program. The processor 1001 reads the computer program from the storage 1003, loads it into the main memory 1002, and executes the above-described processing according to the computer program. The computer program may be distributed to the computer system 1000 via a network.

[0344] [Other embodiments] In the above-described embodiment, a transport vehicle such as a dump truck that travels around the work site to transport cargo is powered from the trolley wire 13. In other embodiments, a work machine, rather than a transport vehicle, may be powered from the trolley wire 13.

[0345] In the above-described embodiment, the capacitor 35 is charged by power from at least one of the trolley wire 13 and the fuel cell 7. The capacitor 35 may also be charged by regenerative braking.

[0346] In the above-described embodiment, the output-type capacitor 35B is charged by power from at least one of the trolley wire 13 and the capacity-type capacitor 29. The output-type capacitor 35B may also be charged by regenerative braking. [Explanation of Symbols]

[0347] 1...Transport vehicle, 2...Dump body, 3...Vehicle body, 4...Running gear, 5...Trolley power receiving device, 6...Power supply pantograph, 7...Fuel cell, 8...Drive motor, 9...Position sensor, 10...Control device, 11...Wheels, 11F...Front wheels, 11R...Rear wheels, 12...Tires, 12F...Front tires, 12R...Rear tires, 13...Trolley wire, 14...Power plant, 15...DC substation, 16...Trolley power supply line, 17...Energy supply system, 18...Vehicle drive system, 19...Electricity Power line, 20...Power line, 21...DC / DC converter, 22...DC / DC converter, 23...DC / DC converter, 24...DC / DC converter, 25...First switch, 26...Second switch, 26B...First switch, 27...Third switch, 27B...Second switch, 28...Diode, 29...Capacitance type capacitor, 29B...Capacitor, 30...Power line, 31...Charging port, 32...Diode, 33...Hydrogen tank, 34... Hydrogen supply device, 35... Energy storage device, 35B... Output type energy storage device, 36... Voltage converter, 37... Inverter, 38... Pump drive motor, 39... Hydraulic pump, 40... Control valve, 41... Hoist cylinder, 42... Inverter, 43... Reduction mechanism, 44... Energy switching control unit, 44B... Energy switching control unit, 44C... Energy switching control unit, 45... FC trolley switching unit, 45B... Energy storage trolley switching unit, 45C... Energy storage trolley switching unit, 46... Trolley capacitor charging unit, 47... Energy control unit, 48... Vehicle operation control unit, 50... Vehicle information storage unit, 51... Terrain information storage unit, 53... Monitor control unit, 54... Monitor, 56... Accelerator / brake pedal, 57... Shift lever, 58... Lift lever, 61... First input unit, 62... Second input unit, 1000... Computer system, 1001... Processor, 1002... Main memory, 1003... Storage, 1004... Interface.

Claims

1. Dump body and A vehicle body that supports the aforementioned dump body, A running gear having drive wheels and supporting the vehicle body, A trolley power receiving device that receives power from the trolley wire, A fuel cell generates electricity by an electrochemical reaction between hydrogen and oxygen, A storage device that is charged by power from at least one of the trolley wire and the fuel cell, An electric motor that generates a driving force to rotate the drive wheel based on power from at least one of the trolley wire and the fuel cell, A shared DC / DC converter that converts the voltage of the trolley wire and the voltage of the fuel cell, A third DC / DC converter that converts the voltage of the aforementioned capacitor, The device includes a switch mechanism for switching between a first state in which power is supplied to the electric motor from the trolley wire via the shared DC / DC converter, a second state in which power is supplied to the electric motor from the fuel cell via the shared DC / DC converter and power is supplied to the electric motor from the capacitor via the third DC / DC converter, and a third state in which power is supplied to the electric motor from the capacitor via the third DC / DC converter. Transport vehicle.

2. A position sensor for detecting the current position of the vehicle body, A terrain information storage unit that stores map information of the work site, The system includes an FC trolley switching unit that controls the switch mechanism to switch between the first state and the second state based on the current position and the map information. The transport vehicle according to claim 1.

3. The route at the work site is defined as a section for operation using an FC battery, a section for operation using only the battery, and a section for operation using trolley power supply. The section where the battery operates independently is defined between the FC battery operating section and the trolley power supply operating section. The FC trolley switching section is, In the FC battery driving section, the switch mechanism is controlled to reach the second state. In the trolley power supply travel section, the switch mechanism is controlled to reach the first state. In the section where the battery operates independently, the switch mechanism is controlled to enter the third state and switch from one of the first and second states to the other. The transport vehicle according to claim 2.

4. The trolley capacitor charging unit is provided to charge the capacitor using power from the trolley wire based on the charge state of the capacitor. The transport vehicle according to claim 1.

5. The power supply to the transport vehicle from the trolley wire, To generate electricity using the fuel cell of the aforementioned transport vehicle, To supply power to the electric motor of the transport vehicle from at least one of the trolley wire and the fuel cell, The electric motor generates a driving force that propels the transport vehicle, The power supply of the transport vehicle is charged by electricity from at least one of the trolley wire and the fuel cell, The shared DC / DC converter converts the voltage of the trolley wire and the voltage of the fuel cell, The third DC / DC converter converts the voltage of the aforementioned capacitor, The switch mechanism includes switching between a first state in which power is supplied to the electric motor from the trolley wire via the shared DC / DC converter, a second state in which power is supplied to the electric motor from the fuel cell via the shared DC / DC converter and power is supplied to the electric motor from the capacitor via the third DC / DC converter, and a third state in which power is supplied to the electric motor from the capacitor via the third DC / DC converter. A method for controlling transport vehicles.

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