dump truck

Abstract

To provide a trolley feeding dump truck which can prevent overdischarge of a battery while suppressing reduction in the conveyance efficiency.SOLUTION: A vehicle control device 12 comprises: a battery residual amount reduction amount calculation unit 12a which calculates a battery residual amount reduction amount (Wcycle) of a non-trolley wire section 24; a battery residual amount target increase calculation unit 12b which calculates a battery residual amount target increase (Wcycle+Wstep) by adding a prescribed battery residual amount additional amount (Wstep) to the battery residual amount reduction amount (Wcycle); a battery residual amount target value calculation unit 12c which calculates a battery residual amount target value (Wref) by adding the battery residual amount target increase (Wcycle+Wstep) to the battery residual amount in the time of travel start of a trolley wire section 22; and a travel operation support unit 12d which supports a travel operation of matching the battery residual amount (Wbat) in the time of travel end of the trolley wire section 22 with the battery residual amount target value (Wref).SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to a trolley-powered dump truck equipped with a battery.

Background Art

[0002] In recent years, in order to reduce the environmental impact, the conversion from conventional fossil fuel-dependent power sources to electric drive has been progressing in each product field. Regarding mining dump trucks that transport ore and overburden from the loading site to the dumping site, there has been an active movement towards the practical application of dump trucks equipped with batteries instead of engines.

[0003] In a mine, multiple dump trucks of the same vehicle type travel back and forth on the route from the loading site to the dumping site, and the operating hours are 24 hours. Since it is important to transport the loaded material efficiently, the transportation efficiency, which is indicated by the total transportation volume of multiple dump trucks traveling per unit time, is emphasized. When the dump truck stops for battery charging, the transportation efficiency will decrease significantly. Therefore, the development of trolley-powered dump trucks that can charge while running has been carried out. A trolley line for supplying power from ground facilities is installed on the mine road. The trolley-powered dump truck drives the driving motor with the power supplied from the trolley line and charges the battery while running in the section where the trolley line is provided (hereinafter referred to as the trolley line section), and drives the driving motor with the discharge power of the battery and runs in the section where the trolley line is not provided (hereinafter referred to as the non-trolley line section).

[0004] The trolley-powered dump truck needs to be sufficiently charged in the trolley line section in order to run through the non-trolley line section. Since there are upper limits to the trolley line power supply and battery charging power due to equipment limitations and battery life, it is necessary to drive at a reduced speed in the trolley line section and ensure the charging time in the trolley line section. On the other hand, it is desirable to suppress the speed reduction in the trolley line section in order to avoid a decrease in transportation efficiency.

[0005] In vehicles such as trolley-powered dump trucks that charge their batteries using overhead lines while driving and run on battery power in sections without overhead lines, there is a technology disclosed in Patent Document 1. According to this technology, it is possible to charge the battery at the maximum charging current determined by the lifespan of the energy storage device while ensuring the amount of charge necessary for the next run in a section without overhead lines. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] International Publication No. 2013 / 153659 [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] Unlike trains and trolleybuses, dump trucks travel on uneven terrain, which means that trolley wire charging may be interrupted due to problems, potentially leading to a decrease in battery level. Therefore, it is necessary not only to ensure sufficient charge for travel on non-trolley wire sections but also to maintain a high battery level. Furthermore, because dump trucks operate continuously for 24 hours and trolley wires cannot be installed at loading and unloading sites where they stop, dump trucks must increase their battery level solely through charging while traveling on trolley wire sections.

[0008] However, in the technology described in Patent Document 1, if the goal is to increase the battery level for the next cycle with a single charge over the trolley wire section, it is necessary to significantly reduce the travel speed over the trolley wire section in order to secure charging time, which reduces transport efficiency.

[0009] The present invention has been made in view of the above problems, and its purpose is to provide a trolley-powered dump truck that can prevent battery over-discharge while suppressing a decrease in transport efficiency. [Means for solving the problem]

[0010] To achieve the above objective, the present invention provides a traction motor, an inverter that converts DC power to AC power and supplies it to the traction motor, a battery, a battery converter that controls the charging and discharging power of the battery, a pantograph that receives power from a trolley wire, and controls the battery converter and the inverter so that power is supplied from the trolley wire to the battery and the traction motor in the trolley wire section, which is a running section where the trolley wire is installed, and controls the battery converter and the inverter so that power is supplied from the battery to the traction motor in the non-trolley wire section, which is a running section where the trolley wire is not installed. A dump truck equipped with a vehicle control device that controls the inverter, wherein the vehicle control device includes: a battery remaining charge reduction calculation unit that calculates the amount of battery remaining charge reduction in the non-trolley wire section; a battery remaining charge target increase range calculation unit that calculates a target battery remaining charge increase range by adding a predetermined battery remaining charge addition amount to the battery remaining charge reduction amount; a battery remaining charge target value calculation unit that calculates a target battery remaining charge value by adding the target battery remaining charge increase range to the battery remaining charge at the start of driving in the trolley wire section; and a driving operation support unit that assists in driving operations to make the battery remaining charge at the end of driving in the trolley wire section match the target battery remaining charge value.

[0011] According to the present invention configured as described above, by supporting a driving operation that gradually increases the battery charge (by the amount added to the battery charge) over multiple driving cycles, it is possible to prevent over-discharge of the battery while suppressing a decrease in transport efficiency. [Effects of the Invention]

[0012] According to the present invention, in a trolley-powered dump truck equipped with a battery, it is possible to prevent over-discharge of the battery while suppressing a decrease in transport efficiency. [Brief explanation of the drawing]

[0013] [Figure 1] This figure shows the configuration of a dump truck in the first embodiment of the present invention. [Figure 2]It is a diagram schematically showing the traveling route of a dump truck in a mine. [Figure 3] It is a diagram showing the configuration of an electric drive system mounted on a dump truck in the first embodiment of the present invention. [Figure 4] It is a diagram showing the variation of the remaining battery level in a non-trolley wire section. [Figure 5] It is a diagram showing the variation of the remaining battery level for each driving cycle. [Figure 6] It is a block diagram showing the process related to the calculation of the target remaining battery level of the vehicle control device. [Figure 7] It is a flowchart of the process repeatedly executed by the remaining battery level variation recording unit during traveling in a trolley wire section. [Figure 8] It is a flowchart of the process repeatedly executed by the remaining battery level variation recording unit during traveling in a non-trolley wire section. [Figure 9] It is a flowchart of the process repeatedly executed by the remaining battery level target value calculation unit during traveling in a non-trolley wire section. [Figure 10] It is a block diagram showing the process related to the traveling operation support of the vehicle control device. [Figure 11] It is a diagram showing an example of the display screen of the display device. [Figure 12] It is a block diagram showing the process related to the calculation of the target remaining battery level of the vehicle control device in the second embodiment of the present invention. [Figure 13] It is a flowchart showing the process of the remaining battery level variation prediction unit. [Figure 14] It is a block diagram showing the process related to the battery charging power control of the vehicle control device in the third embodiment of the present invention. [Figure 15] It is a block diagram showing the process related to the traveling operation support of the vehicle control device in the fourth embodiment of the present invention.

Embodiments for Carrying Out the Invention

[0014] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each figure, equivalent elements are denoted by the same reference numerals, and redundant descriptions will be omitted as appropriate.

Example

[0015] FIG. 1 is a diagram showing the configuration of a dump truck in a first embodiment of the present invention. The dump truck in this embodiment is a trolley-type dump truck that runs on power obtained from trolley wires or battery power.

[0016] In FIG. 1, the dump truck includes a loading platform 8 that is rotatable in the vertical direction at the upper rear of the vehicle body, and a driver's seat 5 that is arranged at the upper front. A pair of left and right driven wheels 3L and 3R are arranged on the front side below the vehicle body, and a pair of left and right drive wheels 4L and 4R are arranged on the rear side below the vehicle body. A traveling motor 2 is connected to the drive wheels 4L and 4R.

[0017] A battery 1 is arranged in front of the vehicle body, and a pair of left and right pantographs 6L and 6R are installed above the vehicle body. In a traveling section where the trolley wires 7L and 7R are arranged (hereinafter referred to as the trolley wire section), the pantographs 6L and 6R contact the two trolley wires 7L and 7R and receive power supply from the trolley wires 7L and 7R. In a traveling section where the trolley wires 7L and 7R are not arranged (hereinafter referred to as the non-trolley wire section), the pantographs 6L and 6R are stored.

[0018] Figure 2 schematically shows the route of a dump truck in a mine. The dump truck travels back and forth along a route from the loading area 20 to the unloading area 21 of the mine. A trolley wire section 22 is provided along the route. Power is supplied to the trolley wires 7L and 7R from the ground power supply equipment 23. When the dump truck is loaded and traveling from the loading area 20 to the unloading area 21, it runs on power supplied from the trolley wires 7L and 7R. When the dump truck is unloaded and traveling from the unloading area 21 to the loading area 20, it runs on the discharge power of battery 1 without receiving power from the trolley wires 7L and 7R. Therefore, one round trip route from the loading area 20 to the unloading area 21 consists of one trolley wire section 22 and other non-trolley wire sections 24. Hereafter, the starting point of the non-trolley wire section 24 will be used as the starting point of one round trip cycle.

[0019] Figure 3 shows the configuration of the electric drive system mounted on the dump truck in this embodiment. In Figure 3, the electric drive system comprises a battery 1, a battery converter 13, an inverter 9, a drive motor 2, a trolley box 10, an external resistor 11, and a vehicle control device 12.

[0020] The vehicle control device 12 receives a signal from the trolley box 10 indicating whether or not it is receiving power from the trolley wires 7L and 7R (hereinafter referred to as the trolley signal), receives the battery charge level from the battery 1, receives the battery charge / discharge power measurement value from the battery converter 13, receives the accelerator pedal operation amount from the accelerator pedal 14, receives the brake pedal operation amount from the brake pedal 15, receives the driving speed from the driving motor 2 or vehicle speed sensor 16, and receives the load amount from the load sensor 17. The battery converter 13 receives the battery charge / discharge power command value from the vehicle control device 12. The inverter 9 receives the torque command value or driving speed command value from the vehicle control device 12. The vehicle control device 12 outputs various information to the display device 18 provided in the driver's seat 5.

[0021] When the dump truck is controlled by the driver's manual operation, torque command values ​​corresponding to the accelerator pedal operation amount and brake pedal operation amount are transmitted from the vehicle control device 12 to the inverter 9. When the dump truck is operating automatically, a driving speed command value is transmitted from the vehicle control device 12 to the inverter 9.

[0022] When the vehicle is running on the discharge power of battery 1 in the non-trolley wire section 24, the discharge power of battery 1 is supplied to inverter 9 via battery converter 13, where it is converted to AC power and supplied to the drive motor 2. As a result, the drive motor 2 drives the drive wheels 4L and 4R, and the dump truck moves. When the vehicle is braking, i.e., when the drive motor 2 is regenerating power, the generated regenerative power is converted to DC power by inverter 9 and supplied to battery converter 13. The battery converter 13 converts the regenerative power into charging power and supplies it to battery 1, charging battery 1. If battery 1 is nearly fully charged and cannot be charged, the external resistor 11 consumes the regenerative power of the drive motor 2.

[0023] When the train runs on power supplied from the trolley wires 7L and 7R in the trolley wire section 22, the power is supplied to the inverter 9 via the pantographs 6L and 6R and the trolley box 10, where it is converted to AC power and supplied to the traction motor 2. The trolley box 10 consists of a circuit breaker, a filter circuit, etc. At the same time as driving the traction motor 2 with the power, the power is also supplied to the battery converter 13. The battery converter 13 converts the power into charging power and supplies it to the battery 1, thereby charging the battery 1.

[0024] The vehicle control device 12 calculates a battery charge / discharge power command value such that it is less than or equal to the maximum battery charge / discharge power specified based on the temperature, degradation state, and lifespan of the battery 1, and does not exceed the upper limit of trolley wire power supply power specified by the maximum allowable power passing through the trolley wires 7L, 7R, pantographs 6L, 6R, and trolley box 10. The battery converter 13 operates so that the battery charge / discharge power matches the battery charge / discharge power command value.

[0025] Since the charging power of battery 1 is limited by the maximum battery charging power and the upper limit of the trolley wire power supply, depending on the length of the trolley wire section 22, it may be necessary to reduce the travel speed in the trolley wire section 22 to ensure sufficient travel time in the trolley wire section 22. To suppress the reduction in speed in the trolley wire section 22 and to gradually increase the battery charge over multiple mine travel cycles is desirable in order to suppress the decrease in transport efficiency. The method for calculating the target battery charge value in the trolley wire section 22 for each travel cycle and the method for calculating the recommended travel speed in the trolley wire section 22 to charge the battery charge to the target value will be described in detail later.

[0026] In Figure 3, the vehicle control device 12 receives the battery charge from battery 1, but the source of the battery charge is not necessarily battery 1. Also, the vehicle control device 12 receives a trolley signal from the trolley box 10, which is a signal indicating whether or not it is receiving power from trolley wires 7L and 7R, but the source of the trolley signal is not necessarily trolley box 10. The vehicle control device 12 receives battery charging power from battery converter 13, but the source of the battery charging power is not necessarily battery converter 13. The vehicle control device 12 receives the driving speed from the driving motor 2 or vehicle speed sensor 16, but the source of the driving speed is not necessarily driving motor 2 or vehicle speed sensor 16. The vehicle control device 12 receives the load from load sensor 17, but the source of the load is not necessarily load sensor 17.

[0027] Figure 4 shows the fluctuation of battery charge in the non-trolley wire section 24. When the traction motor 2 is operating in the non-trolley wire section 24, the battery charge decreases, and when the traction motor 2 is operating in regenerative mode, the battery charge increases. In Figure 4, the battery charge at the start of the non-trolley wire section 24 is called the starting battery charge (Wstart), the battery charge at the end of the non-trolley wire section 24 is called the ending battery charge (Wend), the maximum battery charge in the non-trolley wire section 24 is called the maximum battery charge (Wmax), and the minimum battery charge in the non-trolley wire section 24 is called the minimum battery charge (Wmin). The difference between the maximum battery charge (Wmax) and the starting battery charge (Wstart) is called the maximum increase in battery charge (Wup). The difference between the starting battery charge (Wstart) and the minimum battery charge (Wmin) is called the maximum decrease in battery charge (Wdown). The difference between the starting battery level (Wstart) and the ending battery level (Wend) is defined as the battery level decrease (Wcycle). The three quantities—the battery level decrease (Wcycle), the maximum increase in battery level (Wup), and the maximum decrease in battery level (Wdown)—are collectively referred to as the battery level fluctuation.

[0028] Figure 5 shows the battery charge fluctuations for each driving cycle. The method for calculating the battery charge target value (Wref) in the vehicle control device 12 will be explained using Figure 5. Figure 5 shows the battery charge changes when the battery charge is increased from a low state (hereinafter referred to as battery charge recovery). The vehicle control device 12 calculates the battery charge decrease amount (Wcycle) from the recorded values ​​of battery charge fluctuations in past non-trolley wire sections 24. The battery charge target value (Wref) is calculated by adding the battery charge decrease amount (Wcycle) and the battery charge increase amount (Wstep) to the battery charge (Wbat) when the dump truck enters the trolley wire section 22. Since the battery charge target value (Wref) is calculated each time the vehicle enters the trolley wire section 22, the battery charge target value (Wref) will differ for each driving cycle. Furthermore, the system predicts the maximum battery level (Wmax) and minimum battery level (Wmin) in the next non-trolley wire section 24 when the battery is charged to the target battery level (Wref). The target battery level (Wref) is then adjusted so that the maximum battery level (Wmax) and minimum battery level (Wmin) fall within the range of the upper battery level (Wref_hi) and lower battery level (Wref_low) set based on the battery life. Using this method for calculating the target battery level (Wref), the battery level increases by an additional battery level (Wstep) with each cycle, as shown in Figure 5, and the fluctuation in the battery level remains within the range of the upper battery level (Wref_hi) and lower battery level (Wref_low). Ultimately, the maximum battery level (Wmax) during the driving cycle coincides with the upper battery level (Wref_hi), and the fluctuation in the battery level becomes constant with each driving cycle (hereinafter referred to as the stable battery level).

[0029] Figure 6 is a block diagram showing the process related to the calculation of the battery level target value by the vehicle control device 12. In Figure 6, the vehicle control device 12 includes a battery level fluctuation recording unit 12a, a battery level target increase range calculation unit 12b, a battery level target value calculation unit 12c, and a recommended driving speed calculation unit 12d.

[0030] The battery level fluctuation recording unit 12a receives the trolley signal and the battery level (Wbat) as input. The battery level fluctuation recording unit 12a records past battery level fluctuations in the non-trolley wire section 24, and each time it enters the trolley wire section 22, it calculates the battery level fluctuation amount (Wcycle, Wup, Wdown) based on the recorded values ​​of past battery level fluctuations. In this embodiment, the battery level fluctuation recording unit 12a constitutes a battery level decrease amount calculation unit that calculates the battery level decrease amount (Wcycle). The method for calculating the battery level fluctuation amount (Wcycle, Wup, Wdown) in the battery level fluctuation recording unit 12a will be explained with reference to Figures 7 and 8.

[0031] Figure 7 is a flowchart of the processes that the battery level fluctuation recording unit 12a repeatedly executes while traveling on the trolley wire section 22.

[0032] The battery level fluctuation recording unit 12a first acquires the battery level (Wbat) (step S200) and determines whether or not it has entered the non-trolley wire section 24 (step S201). If the result of the determination in step S201 is NO, the flow is terminated.

[0033] If the result of step S201 is YES, the battery level (Wbat) is recorded as the starting battery level (Wstart), the maximum battery level (Wmax) and minimum battery level (Wmin) are initialized with the battery level (Wbat) respectively (step S202), and the flow is terminated.

[0034] Figure 8 is a flowchart of the processes that the battery level fluctuation recording unit 12a repeatedly executes while traveling in the non-trolley wire section 24.

[0035] The battery level fluctuation recording unit 12a first acquires the battery level (Wbat) (step S200) and determines whether the battery level (Wbat) is less than the minimum battery level (Wmin) (step S201).

[0036] If the result of step S201 is YES, the minimum battery level (Wmin) is updated with the battery level (Wbat) (step S203), and it is determined whether the battery level (Wbat) is greater than the maximum battery level (Wmax) (step S204).

[0037] If the result of step S204 is NO, proceed to step S206.

[0038] If the result of step S204 is YES, the maximum battery level (Wmax) is updated with the current battery level (Wbat) (step S205), and it is determined whether or not the trolley wire section 22 has been entered (step S206). If the result of step S206 is NO, the flow is terminated.

[0039] If the result of step S206 is YES, the remaining battery level (Wbat) is recorded as the final battery level (Wend), the decrease in remaining battery level (Wcycle) is calculated by subtracting the starting battery level (Wstart) from the final battery level (Wend), the maximum increase in remaining battery level (Wup) is calculated by subtracting the starting battery level (Wstart) from the maximum battery level (Wmax), and the maximum decrease in remaining battery level (Wdown) is calculated by subtracting the minimum battery level (Wmin) from the starting battery level (Wstart) (step S207), and the flow ends.

[0040] Through the above process, the battery charge fluctuation (Wcycle, Wup, Wdown) is calculated when the vehicle enters the trolley wire section 22. The battery charge fluctuation (Wcycle, Wup, Wdown) may be calculated from the battery charge fluctuation of one driving cycle, or it may be calculated by applying a filter (e.g., moving average) to the battery charge fluctuation (Wcycle, Wup, Wdown) of multiple past driving cycles. Furthermore, when retaining and calculating the battery charge fluctuation (Wcycle, Wup, Wdown) of multiple cycles using a filter, the retained value and the calculated value may be corrected based on the load. The correction of the battery charge fluctuation (Wcycle, Wup, Wdown) based on the load will now be explained. The change in battery charge fluctuations (Wcycle, Wup, Wdown) due to load capacity is set as a load capacity correction table. When retaining battery charge fluctuations (Wcycle, Wup, Wdown), the data is converted from the current load capacity to the standard load capacity using the load capacity correction table before being retained. When calculating using filtering, the data is calculated from the standard load capacity to the current load capacity using the load capacity correction table before being calculated. By correcting based on load capacity, the impact of load capacity changes on the calculation results of battery charge fluctuations (Wcycle, Wup, Wdown) can be reduced, even if the load capacity differs from one driving cycle to the next.

[0041] Of the battery charge fluctuations (Wcycle, Wup, Wdown), the battery charge decrease (Wcycle) is input to the battery charge target increase calculation unit 12b. When the battery charge is restored, due to the limitations of the maximum battery charging power and the upper limit of the trolley wire power supply, it may be necessary to reduce the speed in the trolley wire section 22 to ensure sufficient charging time in the trolley wire section 22. In such cases of battery charge restoration, the minimum average running speed (Vrecover) of the trolley wire section 22 that can be tolerated is set, and the allowable average speed reduction rate (K) of the trolley wire section 22 is defined as the ratio of the minimum average running speed (Vrecover) to the average running speed (Vstable) of the trolley wire section 22 when the battery charge is stable, as shown in Equation 1.

[0042]

number

[0043] The battery charge target increase calculation unit 12b calculates the ratio of the longest allowable trolley wire section travel time to the trolley wire section travel time when the battery charge is stable, based on the allowable average speed reduction rate (K) of the trolley wire section 22, and determines the battery charge addition amount (Wstep) from the battery charge increase amount (= battery charge decrease amount (Wcycle)) when traveling through the trolley wire section 22 at the average travel speed (Vstable). The battery charge addition amount (Wstep) is calculated, for example, using equation 2.

[0044]

number

[0045] By transforming equation 2 using equation 1, we obtain equation 3.

[0046]

number

[0047] Note that the battery charge addition amount (Wstep) may not be calculated by the battery charge target increase calculation unit 12b, but may be set as a constant. If the battery charge addition amount (Wstep) is set as a constant, the driving time when driving through the trolley wire section 22 at the target average driving speed is calculated, and the battery charge addition amount (Wstep) is set as the value obtained by subtracting the battery charge decrease amount (Wcycle) from the battery charge increase during that driving time.

[0048] The battery level target value calculation unit 12c receives the trolley signal, battery level, battery level fluctuation, target increase range for battery level, and upper and lower limits for battery level as input. The method for calculating the battery level target value in the battery level target value calculation unit 12c will be explained using Figure 9.

[0049] Figure 9 is a flowchart of the processes that the battery remaining target value calculation unit 12c repeatedly executes while traveling in the non-trolley wire section 24.

[0050] The battery level target value calculation unit 12c first obtains the battery level (Wbat), battery level fluctuation amount (Wcycle, Wup, Wdown), battery level upper limit (Wref_hi), and battery level lower limit (Wref_low) (step S300), and then determines whether or not the trolley wire section 22 has been entered (step S301). If the result of the determination in step S301 is NO, the flow is terminated.

[0051] If the result of step S301 is YES, the battery level target value (Wref) is calculated by adding the battery level decrease amount (Wcycle) and the battery level increase amount (Wstep) to the battery level (Wbat) (step S302). Then, the sum of the battery level target value (Wref) and the maximum increase in battery level (Wup) is calculated as the predicted value of the maximum battery level (Wmax) in the next non-trolley wire section 24 when the battery is charged to the battery level target value (Wref), and it is determined whether this predicted value is greater than the battery level upper limit value (Wref_hi) (step S303).

[0052] If the result of step S303 is YES, the value obtained by subtracting the maximum increase in battery level (Wup) from the upper limit of battery level (Wref_hi) is set as the target battery level (Wref) (step S304). Then, as a predicted value for the minimum battery level (Wmin) in the next non-trolley wire section 24 when the battery is charged to the target battery level (Wref), the value obtained by subtracting the maximum decrease in battery level (Wdown) from the target battery level (Wref) is calculated, and it is determined whether this predicted value is smaller than the lower limit of battery level (Wref_low) (step S305). If the result of step S305 is NO, the flow is terminated.

[0053] If the result of step S305 is YES, the battery level target value (Wref) is set to the value obtained by subtracting the maximum increase in battery level (Wup) from the upper limit of battery level (Wref_hi) (step S306), and the flow ends.

[0054] Through the above process, a target battery level value (Wref) is calculated that will result in a charge amount equal to the sum of the battery level decrease (Wcycle) and the battery level increase (Wstep) when entering the trolley wire section 22. The target battery level value (Wref) is then corrected so that the predicted values ​​of the maximum battery level (Wmax) and minimum battery level (Wmin) in the next non-trolley wire section 24 fall within the range of the upper battery level value (Wref_hi) and the lower battery level value (Wref_low).

[0055] Next, we will explain the driving support operations to match the battery level (Wbat) at the end of travel in the trolley wire section 22 to the battery level target value (Wref).

[0056] Figure 10 is a block diagram showing the processes related to driving operation support of the vehicle control device 12. In this embodiment, the vehicle control device 12 calculates a recommended driving speed for the trolley wire section 22 (hereinafter referred to as the recommended driving speed) that can make the remaining battery charge (Wbat) at the end of driving in the trolley wire section 22 match the target battery charge (Wref), and displays this speed to the driver.

[0057] In Figure 10, the vehicle control device 12 includes a trolley wire section length calculation unit 12e that calculates the length of the trolley wire section, and a recommended driving speed calculation unit 12d that calculates the recommended driving speed for the trolley wire section 22. The recommended driving speed calculation unit 12d constitutes a driving operation support unit that assists in driving operations to match the battery level (Wbat) at the end of driving in the trolley wire section 22 with the battery level target value (Wref).

[0058] The trolley wire section length calculation unit 12e takes the trolley signal and the running speed as input and calculates the trolley wire section length by integrating the running speed of the trolley wire section 22. The trolley wire section length may be calculated from the running speed of one past running cycle, or it may be calculated by storing the trolley wire section lengths calculated over multiple past running cycles and applying a filter (e.g., moving average processing) to them. Also, if the trolley wire section length is known, it may not be calculated by the trolley wire section length calculation unit 12e and may be set as a constant value. Furthermore, the trolley wire section length calculation unit 12e may not take the running speed as input, but instead take the vehicle's current position as input and calculate the distance traveled in the trolley wire section 22 as the trolley wire section length.

[0059] The recommended driving speed calculation unit 12d receives the trolley signal, driving speed, battery level target value (Wref), battery charging power, and battery level (Wbat) as input. While driving in the trolley wire section 22, the recommended driving speed calculation unit 12d calculates the remaining charge by subtracting the battery level (Wbat) from the battery level target value (Wref), calculates the remaining charging time by dividing the remaining charge by the battery charging power, calculates the length of the trolley wire section already traveled by integrating the driving speed in the trolley wire section 22, calculates the remaining trolley wire section length by subtracting the length of the trolley wire section already traveled from the trolley wire section length, and calculates the recommended driving speed by dividing the remaining trolley wire length by the remaining charging time. The recommended driving speed calculation unit 12d repeatedly performs these processes while driving in the trolley wire section 22 and updates the recommended driving speed.

[0060] The recommended speed calculation unit 12d may also calculate the distance traveled in the trolley wire section 22 as the length of the trolley wire section traveled, instead of taking the current position as input, instead of the driving speed. Furthermore, the recommended speed calculation unit 12d may perform filtering (e.g., moving average processing) on ​​the battery charging power before calculating the remaining charging time. The recommended speed and remaining charging time calculated by the recommended speed calculation unit 12d are input to the display device 18 along with the trolley signal, the battery level target value (Wref), and the battery level (Wbat).

[0061] Figure 11 shows an example of the display screen of the display device 18. In Figure 11, the display screen of the display device 18 consists of an area 18a that displays the remaining charging time, an area 18b that displays the recommended driving speed, an area 18c that displays the target battery level (Wref), and an area 18d that displays the battery level. In addition, areas that display the vehicle speed and the operating status of the electric drive system may be added as components of the display screen. Note that in order to achieve the effect of matching the battery level (Wbat) at the end of driving in the trolley wire section 22 with the target battery level (Wref), it is sufficient to have at least an area 18b that displays the recommended driving speed.

[0062] (summary) In this embodiment, a dump truck is provided with a traction motor 2, an inverter 9 that converts DC power to AC power and supplies it to the traction motor 2, a battery 1, a battery converter 13 that controls the charging and discharging power of the battery 1, pantographs 6L and 6R that receive power from trolley wires 7L and 7R, and a vehicle control device 12 that controls the battery converter 13 and inverter 9 so that power is supplied from trolley wires 7L and 7R to the battery 1 and the traction motor 2 in the trolley wire section 22 where trolley wires 7L and 7R are installed, and controls the battery converter 13 and inverter 9 so that power is supplied from the battery 1 to the traction motor 2 in the non-trolley wire section 24 where trolley wires 7L and 7R are not installed. In this system, the vehicle control device 12 includes a battery remaining charge reduction calculation unit 12a that calculates the amount of battery remaining charge reduction (Wcycle) in the non-trolley wire section 24, a battery remaining charge target increase range calculation unit 12b that calculates the battery remaining charge target increase range (Wcycle + Wstep) by adding a predetermined battery remaining charge addition amount (Wstep) to the battery remaining charge reduction (Wcycle), a battery remaining charge target value calculation unit 12c that calculates the battery remaining charge target value (Wref) by adding the battery remaining charge target increase range (Wcycle + Wstep) to the battery remaining charge at the start of driving in the trolley wire section 22, and a driving operation support unit 12d that assists in driving operations to make the battery remaining charge (Wbat) at the end of driving in the trolley wire section 22 match the battery remaining charge target value (Wref).

[0063] According to this embodiment configured as described above, by supporting a driving operation that gradually increases the battery charge (Wbat) over multiple driving cycles (by the amount of battery charge added (Wstep) each time), it is possible to prevent over-discharge of battery 1 while suppressing a decrease in transport efficiency.

[0064] Furthermore, the dump truck in this embodiment is equipped with a display device 18, and the driving operation support unit 12d consists of a recommended driving speed calculation unit 12d that calculates the recommended driving speed in the trolley wire section 22. The recommended driving speed calculation unit 12d calculates the remaining charging time in the trolley wire section 22 by dividing the difference between the target battery charge value (Wref) and the battery charge value (Wbat) by the battery charging power, calculates the recommended driving speed by dividing the remaining driving distance in the trolley wire section 22 by the remaining charging time, and outputs the recommended driving speed to the display device 18. As a result, by operating according to the recommended driving speed displayed on the display device 18, it is possible to make the battery charge value (Wbat) at the end of driving in the trolley wire section 22 match the target battery charge value (Wref).

[0065] Furthermore, the battery charge reduction calculation unit 12a in this embodiment is composed of a battery charge fluctuation recording unit 12a that records the battery charge fluctuations in the non-trolley wire section 24, and the battery charge fluctuation recording unit 12a calculates the battery charge reduction (Wcycle) using the recorded values ​​of the battery charge fluctuations. This makes it possible to calculate the battery charge reduction (Wcycle) from past battery charge fluctuations in the non-trolley wire section 24.

[0066] Furthermore, the battery charge target increase calculation unit 12b in this embodiment calculates the battery charge increase amount (Wstep) by multiplying the difference obtained by subtracting the minimum average running speed (Vrecover) of the trolley wire section 22 when the battery charge is recovered and the battery charge increase amount (Wstep) becomes greater than zero from the average running speed (Vstable) of the trolley wire section 22 when the battery charge is stable and the battery charge increase amount (Wstep) is zero by the battery charge decrease amount (Wcycle) (Equation 3). This makes it possible to keep the decrease in running speed of the trolley wire section 22 within an acceptable range.

[0067] Furthermore, the battery remaining charge target value calculation unit 12c in this embodiment calculates predicted values ​​for the maximum battery remaining charge (Wmax) and minimum battery remaining charge (Wmin) when the battery 1 is charged to the battery remaining charge target value (Wref) in the trolley wire section 22 and then driven in the non-trolley wire section 24. If the predicted value of the maximum battery remaining charge (Wmax) exceeds the upper limit of the battery remaining charge (Wref_hi), which is set based on the battery life, the battery remaining charge target value (Wref) is corrected to decrease. If the predicted value of the minimum battery remaining charge (Wmin) falls below the lower limit of the battery remaining charge (Wref_low), which is set based on the battery life, the battery remaining charge target value (Wref) is corrected to increase. This makes it possible to keep the fluctuation of the battery remaining charge within the range of the upper limit of the battery remaining charge (Wref_hi) and the lower limit of the battery remaining charge (Wref_low). [Examples]

[0068] A second embodiment of the present invention will be described, focusing on the differences from the first embodiment. In the first embodiment, the target battery level (Wref) was calculated using the battery level fluctuation amount (Wcycle, Wup, Wdown) calculated based on the recorded values ​​of the battery level fluctuation. In this embodiment, however, the target battery level (Wref) is calculated using the battery level fluctuation amount (Wcycle, Wup, Wdown) calculated based on the predicted values ​​of the battery level fluctuation.

[0069] Figure 12 is a block diagram showing the process related to the calculation of the battery level target value of the vehicle control device 12 in this embodiment. In Figure 12, the vehicle control device 12 in this embodiment has a battery level fluctuation prediction unit 12f instead of the battery level fluctuation recording unit 12a (shown in Figure 6) in the first embodiment. The battery level fluctuation prediction unit 12f calculates predicted values ​​of the battery level fluctuation amount (Wcycle, Wup, Wdown) based on the trolley signal, battery level, load amount, and road gradient information. In this embodiment, the battery level fluctuation prediction unit 12f constitutes a battery level decrease amount calculation unit that calculates the battery level decrease amount (Wcycle).

[0070] The battery level fluctuation prediction unit 12f is further input with the load amount and road gradient information. When entering the non-trolley wire section 24, the battery level fluctuation prediction unit 12f calculates predicted values ​​for the battery level fluctuation amount (Wcycle, Wup, Wdown) in the non-trolley wire section 24 from the load amount and road gradient information. The road gradient information can be set in advance as a default value, or it can be calculated from the fluctuation of gradient measurement values ​​from past driving cycles.

[0071] Figure 13 is a flowchart showing the processing of the battery level fluctuation prediction unit 12f.

[0072] The battery level fluctuation prediction unit 12f first divides the non-trolley wire section 24 into N sections and assigns section numbers from 1 to N to each section (step S400).

[0073] In step S401, the section number of the section to be calculated (hereinafter referred to as the calculation target section) is set to 1, and the battery level (Wbat) when entering the non-trolley wire section 24 is set to the battery level (Wout_before) when exiting the section (step S401).

[0074] Following step S401, the elevation difference (Hdiff) between the start and end points of the calculation target division section is calculated from the gradient information of the calculation target division section (step S402).

[0075] Following step S402, the energy consumed according to the difference in elevation (Hdiff) (hereinafter referred to as the energy consumed due to elevation difference) (W1) is calculated by multiplying the total weight (Mtotal), which is the sum of the vehicle weight and the load, the difference in elevation (Hdiff), and the acceleration due to gravity (g) (step S403).

[0076] Following step S403, the energy consumed according to the rolling resistance (Fc) (hereinafter referred to as resistance energy consumption) (W2) is calculated. The rolling resistance (Fc) is calculated by multiplying the normal force, which is obtained by product of the total weight (Mtotal) and the acceleration due to gravity (g), by the rolling resistance coefficient (Rc). The rolling resistance coefficient (Rc) is the ratio of the rolling resistance (Fc) to the normal force. A constant value is set in advance, or the change in the rolling resistance coefficient (Rc) with respect to the load is saved as a table, and the rolling resistance coefficient (Rc) that changes according to the load is used by referring to the table. The resistance energy consumption (W2) is calculated by multiplying the rolling resistance (Fc) by the length (L) of the division section to be calculated. The sum of the energy consumed due to elevation difference (W1) and the resistance energy consumption (W2) is the energy consumed during travel in the division section to be calculated.

[0077] Following step S404, the difference in battery remaining capacity (Wdiff) is calculated by adding the energy loss (Wloss) that occurs when converting the charge / discharge power of battery 1 into tire driving force to the energy consumed due to elevation difference (W1) and the energy consumed due to resistance (W2) (step S405). The energy loss (Wloss) may be calculated by multiplying the energy consumed due to elevation difference (W1) and the energy consumed due to resistance (W2) by a fixed ratio, or the change in energy loss (Wloss) with respect to the sum of the energy consumed due to elevation difference (W1) and the energy consumed due to resistance (W2) may be stored as a table, and the energy loss (Wloss) may be calculated by referring to this table.

[0078] Following step S405, the remaining battery level of the target segment at the time of exit (Wout) is calculated and saved by subtracting the battery level difference (Wdiff) from the remaining battery level of the previous segment at the time of exit (Wout_before) (step S406).

[0079] Following step S406, it is determined whether the number of the section to be calculated is N (meaning that the battery level at exit (Wout) for all divided sections has been calculated) (step S407). If the result of the determination in step S407 is NO, 1 is added to the section number of the divided section to be calculated, the battery level at exit of the previous divided section (Wout_before) is set to the battery level at exit of the divided section to be calculated (Wout) (step S408), and the process returns to step S402.

[0080] If the result of step S407 is YES, the maximum value of the battery level at the exit of each segment (Wout) is taken as the maximum increase in battery level (Wup), and the minimum value is taken as the maximum decrease in battery level (Wdown). The decrease in battery level (Wcycle) is calculated by subtracting the battery level at the exit of the Nth segment (Wout) from the battery level when entering the non-trolley wire section 24 (Wbat) (step S409), and the flow ends.

[0081] Furthermore, the method for predicting battery charge fluctuations in the non-trolley wire section 24 is not particularly limited, as long as it can calculate predicted values ​​for battery charge fluctuations (Wcycle, Wup, Wdown). For example, the vehicle dynamics model and the electric drive system model may be used to input load capacity and road gradient information, and predicted values ​​for battery charge fluctuations (Wcycle, Wup, Wdown) may be calculated through numerical analysis.

[0082] (summary) In this embodiment, the battery charge reduction calculation unit 12f is composed of a battery charge fluctuation prediction unit 12f that predicts the fluctuation of the battery charge in the non-trolley wire section 24. The battery charge fluctuation prediction unit 12f uses the load capacity of the dump truck and the gradient information of the non-trolley wire section 24 to calculate a predicted value of the fluctuation of the battery charge in the non-trolley wire section 24 (battery charge at exit of each section (Wout)), and uses the predicted value of the fluctuation of the battery charge to calculate the battery charge reduction amount (Wcycle) in the non-trolley wire section 24.

[0083] In this embodiment configured as described above, the same effects as in the first embodiment can be achieved. Furthermore, by calculating the battery charge reduction (Wcycle) in the non-trolley wire section 24 using the load capacity of the dump truck and the gradient information of the non-trolley wire section 24, it becomes possible to set the battery charge target value (Wref) to a more appropriate value. [Examples]

[0084] A third embodiment of the present invention will be described, focusing on the differences from the first embodiment. In this embodiment, the battery charging power is controlled while traveling in the trolley wire section 22, so that the remaining battery charge (Wbat) at the end of travel in the trolley wire section 22 matches the target battery charge (Wref).

[0085] Figure 14 is a block diagram showing the process related to battery charging power control of the vehicle control device 12 in this embodiment. In Figure 14, the vehicle control device 12 has a trolley wire section travel time calculation unit 12g that calculates the travel time in the trolley wire section 22, and a battery charging power command value calculation unit 12h that calculates the battery charging power command value.

[0086] The trolley wire section travel time calculation unit 12g calculates the time during which the trolley signal remains ON as the trolley wire section travel time. The trolley wire section travel time can be calculated from the trolley wire section travel time of one travel cycle, or it can be calculated by storing the trolley wire section travel times calculated over multiple past travel cycles and applying a filter (e.g., moving average processing) to them. Alternatively, if the trolley wire section travel time is known, the trolley wire section travel time calculation unit 12g may be omitted, and the trolley wire section travel time may be set to a constant value.

[0087] The battery charging power command value calculation unit 12h calculates the remaining trolley wire section travel time by subtracting the elapsed time since entering the trolley wire section 22 from the time traveled in the trolley wire section 22, calculates the remaining charge by subtracting the battery level from the target battery level, calculates the battery charging power command value by dividing the remaining charge by the remaining trolley wire section travel time, and outputs the battery charging power command value to the battery converter 13. The battery converter 13 controls the battery charging power to match the battery charging power command value.

[0088] (summary) The vehicle control device 12 in this embodiment includes a trolley wire section travel time calculation unit 12g that calculates the travel time in the trolley wire section 22, and a battery charge power command value calculation unit 12h that calculates the remaining travel time in the trolley wire section 22 by subtracting the elapsed time since entering the trolley wire section 22 from the travel time, calculates the remaining charge amount by subtracting the battery charge amount (Wbat) from the battery charge amount target value (Wref), calculates the battery charge power command value by dividing the remaining charge amount by the remaining travel time, and outputs the battery charge power command value to the battery converter 13.

[0089] In this embodiment configured as described above, the same effects as in the first embodiment can be achieved. Furthermore, since the battery can be charged to the target battery level (Wref) while minimizing the battery charging power, it is possible to suppress the degradation of battery 1. [Examples]

[0090] A fourth embodiment of the present invention will be described, focusing on the differences from the first embodiment. In the first embodiment, the recommended running speed in the trolley wire section 22 was calculated and displayed to the driver, but in this embodiment, the running motor 2 is driven so that the running speed in the trolley wire section 22 matches the recommended running speed.

[0091] Figure 15 is a block diagram showing the processing related to the driving operation support of the vehicle control device 12. In Figure 15, the recommended driving speed calculation unit 12d outputs a driving speed command value corresponding to the recommended driving speed to the inverter 9. As a result, the inverter 9 drives the driving motor 2 to match the recommended driving speed, and the dump truck drives at the recommended driving speed. In this embodiment, the recommended driving speed calculation unit 12d, similar to the first embodiment, constitutes a driving operation support unit that supports driving operations to match the battery level (Wbat) at the end of driving in the trolley wire section 22 with the battery level target value (Wref).

[0092] (summary) In this embodiment, the driving operation support unit 12d consists of a recommended driving speed calculation unit 12d that calculates a recommended driving speed for the trolley wire section 22. The recommended driving speed calculation unit 12d calculates the remaining charging time for the trolley wire section 22 by dividing the difference between the target battery charge value (Wref) and the battery charge (Wbat) by the battery charging power, calculates the recommended driving speed by dividing the remaining driving distance for the trolley wire section 22 by the remaining charging time, and outputs a driving speed command value corresponding to the recommended driving speed to the inverter 9.

[0093] In this embodiment configured as described above, the same effects as in the first embodiment are achieved. Furthermore, since the running speed in the trolley wire section 22 can be matched to the recommended running speed regardless of the driver's operation, it becomes possible to accurately match the remaining battery charge (Wbat) at the end of running in the trolley wire section 22 to the target battery charge value (Wref). [Explanation of symbols]

[0094] 1...Battery, 2...Traction motor, 3L,3R...Driven wheels, 4L,4R...Drive wheels, 5...Driver's cab, 6L,6R...Pantograph, 7L,7R...Trolley wire, 8...Cargo bed, 9...Inverter, 10...Trolley box, 11...External resistor, 12...Vehicle control device, 12a...Battery level fluctuation recording unit (Battery level decrease calculation unit), 12b...Battery level target increase range calculation unit, 12c...Battery level target value calculation unit, 12d...Recommended driving speed calculation unit (Driving operation support unit), 12 e...Trolley wire section length calculation unit, 12f...Battery remaining charge fluctuation prediction unit (battery remaining charge decrease amount calculation unit), 12g...Trolley wire section running time calculation unit, 12h...Battery charging power command value calculation unit, 13...Battery converter, 14...Accelerator pedal, 15...Brake pedal, 16...Vehicle speed sensor, 17...Load amount sensor, 18...Display device, 18a~18d...Area, 20...Loading area, 21...Unloading area, 22...Trolley wire section, 23...Ground power supply equipment, 24...Non-trolley wire section.

Claims

1. The driving motor and An inverter that converts DC power to AC power and supplies it to the aforementioned drive motor, Battery and A battery converter that controls the charging and discharging power of the aforementioned battery, A pantograph that receives power from the overhead wire, Display device and A dump truck is equipped with a vehicle control device that controls the battery converter and inverter so that power is supplied from the trolley wire to the battery and the drive motor in the trolley wire section, which is a driving section where the trolley wire is installed, and controls the battery converter and inverter so that power is supplied from the battery to the drive motor in the non-trolley wire section, which is a driving section where the trolley wire is not installed, The aforementioned vehicle control device is A battery remaining charge reduction calculation unit calculates the amount of battery remaining charge reduction in the non-trolley wire section, A battery remaining charge target increase range calculation unit calculates the target increase range by adding a predetermined amount of battery remaining charge to the amount of battery remaining charge decrease, A battery remaining target value calculation unit calculates a battery remaining target value by adding the battery remaining amount at the start of operation in the trolley wire section to the battery remaining amount at the start of operation in the trolley wire section, It includes a driving operation support unit that assists in driving operations to match the remaining battery level at the end of driving in the trolley wire section to the target battery level, The aforementioned running operation support unit is comprised of a recommended running speed calculation unit that calculates the recommended running speed for the overhead wire section. The aforementioned recommended driving speed calculation unit, The remaining charging time in the trolley wire section is calculated by dividing the difference between the target battery level and the remaining battery level by the battery charging power. The recommended driving speed is calculated by dividing the remaining driving distance of the trolley wire section by the remaining charging time. The recommended driving speed is output to the display device. A dump truck characterized by the following features.

2. A motor for driving, An inverter that converts DC power to AC power and supplies it to the aforementioned drive motor, Battery and A battery converter that controls the charging and discharging power of the aforementioned battery, A pantograph that receives power from the overhead wire, A dump truck is equipped with a vehicle control device that controls the battery converter and inverter so that power is supplied from the trolley wire to the battery and the drive motor in the trolley wire section, which is a driving section where the trolley wire is installed, and controls the battery converter and inverter so that power is supplied from the battery to the drive motor in the non-trolley wire section, which is a driving section where the trolley wire is not installed, The aforementioned vehicle control device is A battery remaining charge reduction calculation unit calculates the amount of battery remaining charge reduction in the non-trolley wire section, A battery remaining charge target increase range calculation unit calculates the target increase range by adding a predetermined amount of battery remaining charge to the amount of battery remaining charge decrease, A battery remaining target value calculation unit calculates a battery remaining target value by adding the battery remaining amount at the start of operation in the trolley wire section to the battery remaining amount at the start of operation in the trolley wire section, It includes a driving operation support unit that assists in driving operations to match the remaining battery level at the end of driving in the trolley wire section to the target battery level, The aforementioned running operation support unit is comprised of a recommended running speed calculation unit that calculates the recommended running speed for the overhead wire section. The aforementioned recommended driving speed calculation unit, The remaining charging time for the trolley wire section is calculated by dividing the difference between the target battery level and the current battery level by the battery charging power. The recommended driving speed is calculated by dividing the remaining driving distance of the trolley wire section by the remaining charging time. The inverter outputs a driving speed command value corresponding to the recommended driving speed. A dump truck characterized by the following features.

3. In the dump truck according to claim 1, The battery level reduction calculation unit is comprised of a battery level fluctuation recording unit that records the fluctuations in the battery level in the non-trolley wire section. The battery level fluctuation recording unit calculates the amount of battery level decrease using the recorded value of the battery level fluctuation. A dump truck characterized by the following features.

4. In the dump truck according to claim 1, The battery remaining charge reduction calculation unit is comprised of a battery remaining charge fluctuation prediction unit that predicts the fluctuation in the battery remaining charge in the non-trolley wire section. The aforementioned battery level fluctuation prediction unit is: Using the load capacity of the dump truck and the gradient information of the non-trolley wire section, a predicted value for the battery charge fluctuation in the non-trolley wire section is calculated. The amount of battery charge reduction in the non-trolley wire section is calculated using the predicted value of the battery charge fluctuation. A dump truck characterized by the following features.

5. A motor for driving, An inverter that converts DC power to AC power and supplies it to the aforementioned drive motor, Battery and A battery converter that controls the charging and discharging power of the aforementioned battery, A pantograph that receives power from the overhead wire, A dump truck is equipped with a vehicle control device that controls the battery converter and inverter so that power is supplied from the trolley wire to the battery and the drive motor in the trolley wire section, which is a driving section where the trolley wire is installed, and controls the battery converter and inverter so that power is supplied from the battery to the drive motor in the non-trolley wire section, which is a driving section where the trolley wire is not installed, The aforementioned vehicle control device is A battery remaining charge reduction calculation unit calculates the amount of battery remaining charge reduction in the non-trolley wire section, A battery remaining charge target increase range calculation unit calculates the target increase range by adding a predetermined amount of battery remaining charge to the amount of battery remaining charge decrease, A battery remaining target value calculation unit calculates a battery remaining target value by adding the battery remaining amount at the start of operation in the trolley wire section to the battery remaining amount at the start of operation in the trolley wire section, It includes a driving operation support unit that assists in driving operations to match the remaining battery level at the end of driving in the trolley wire section to the target battery level, The aforementioned battery remaining charge target increase calculation unit: The amount of battery charge added is calculated by multiplying the difference obtained by dividing the difference between the average running speed of the trolley wire section when the battery level is stable and the amount of battery charge added becomes zero, and the minimum average running speed of the trolley wire section that is allowed when the battery level recovers to a point where the amount of battery charge added becomes greater than zero, by the minimum average running speed, and multiplying this difference by the amount of battery charge reduction. A dump truck characterized by the following features.

6. A motor for driving, An inverter that converts DC power to AC power and supplies it to the aforementioned drive motor, Battery and A battery converter that controls the charging and discharging power of the aforementioned battery, A pantograph that receives power from the overhead wire, A dump truck is equipped with a vehicle control device that controls the battery converter and inverter so that power is supplied from the trolley wire to the battery and the drive motor in the trolley wire section, which is a driving section where the trolley wire is installed, and controls the battery converter and inverter so that power is supplied from the battery to the drive motor in the non-trolley wire section, which is a driving section where the trolley wire is not installed, The aforementioned vehicle control device is A battery remaining charge reduction calculation unit calculates the amount of battery remaining charge reduction in the non-trolley wire section, A battery remaining charge target increase range calculation unit calculates the target increase range by adding a predetermined amount of battery remaining charge to the amount of battery remaining charge decrease, A battery remaining target value calculation unit calculates a battery remaining target value by adding the battery remaining amount at the start of operation in the trolley wire section to the battery remaining amount at the start of operation in the trolley wire section, It includes a driving operation support unit that assists in driving operations to match the remaining battery level at the end of driving in the trolley wire section to the target battery level, The aforementioned battery remaining target value calculation unit, After charging the battery to the target battery level in the trolley wire section, the predicted maximum and minimum battery levels are calculated when the vehicle travels through the non-trolley wire section. If the predicted maximum battery level exceeds the upper limit of the battery level set based on the battery life, the target battery level is corrected to decrease. If the predicted minimum battery level falls below the lower limit of the battery level set based on battery life, the target battery level is corrected to increase. A dump truck characterized by the following features.

7. In the dump truck according to claim 1, The aforementioned vehicle control device is A trolley wire section travel time calculation unit that calculates the travel time in the aforementioned trolley wire section, The battery includes a battery charging power command value calculation unit that calculates the remaining travel time in the trolley wire section by subtracting the elapsed time since entering the trolley wire section from the aforementioned travel time, calculates the remaining charge amount by subtracting the battery charge amount from the battery charge target value, calculates the battery charging power command value by dividing the remaining charge amount by the remaining travel time, and outputs the battery charging power command value to the battery converter. A dump truck characterized by the following features.

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