阅读说明：本技术 用于采矿运输卡车的所有电气操作的系统和方法 (System and method for all electrical operation of mining haul trucks ) 是由 J.马宗达 于 2014-09-26 设计创作，主要内容包括：用所有电力源操作由电气轮马达驱动的采矿运输卡车；也就是说,没有柴油机。当在装载场地上行进时,采矿运输卡车由可以包括超级电容器组的车载能量存储系统供电。采矿运输卡车然后移动到滑接斜坡的底部,并且被耦合到滑接线。当上坡行进时,采矿运输卡车通过滑接线供电,并且车载能量存储系统通过滑接线被充电。当采矿运输卡车到达滑接斜坡的顶部时,采矿运输卡车从滑接线去耦。当在卸载场地上行进时,采矿运输卡车由车载能量存储系统供电。车载能量存储系统还可以通过制动期间由轮马达生成的减速能量来被充电。(Operating a mining haul truck driven by an electric wheel motor with all sources of electrical power; that is, there is no diesel engine. When travelling on the loading site, the mining haul truck is powered by an onboard energy storage system, which may include a bank of ultracapacitors. The mining haul truck then moves to the bottom of the trolley ramp and is coupled to the trolley line. When travelling uphill, the mining haul truck is powered through a trolley line, and the on-board energy storage system is charged through the trolley line. When the mining haul truck reaches the top of the trolley ramp, the mining haul truck is decoupled from the trolley line. While traveling on the unloading site, the mining haul truck is powered by the on-board energy storage system. The on-board energy storage system may also be charged by the retarding energy generated by the wheel motors during braking.)

1. A method for supplying power to electric motors on all electrically driven mining haul trucks equipped with an on-board energy storage system, the method comprising the steps of:

calculating energy required for a mining haul drive operation and performing at least one of the following:

(a) supplying power to the electric motor from the on-board energy storage system;

(b) charging the on-board energy storage system with power from a trolley power system;

(c) charging the on-board energy storage system with power generated by the electric motor during braking of the mining haul truck;

propelling the mining haul truck with electrical power supplied by the trolley power system alone, or by the on-board energy storage system alone, or by a combination of the trolley power system and the on-board energy storage system, without mechanical power supplied by a mechanical engine.

2. The method of claim 1, wherein the required energy is calculated based on a haul profile and a payload state of the mining haul truck.

3. The method of claim 2, wherein the shipping profile includes distance, slope of the floor, and travel path.

4. The method of any of claims 1-3, wherein:

the on-board energy storage system includes at least one ultracapacitor.

5. The method of any of claims 1-3, wherein:

the on-board energy storage system includes at least one battery.

6. The method of any of claims 1 to 3, further comprising:

supplying power to the motor from the trolley power system and/or charging the on-board energy storage system with power from the trolley power system when the mining haul truck is coupled to trolley lines of the trolley power system.

7. The method of claim 6, further comprising:

supplying power to the electric motor from the on-board energy storage system when the mining haul truck is decoupled from the trolley line.

8. The method of claim 6, further comprising:

after the onboard energy storage system is fully charged with power generated by the electric motor during braking of the mining haul truck, the power generated by the electric motor is returned to a utility grid via the trolley line.

9. A power system for supplying power to electric motors on all electrically driven mining haul trucks, the power system comprising:

an on-board energy storage system and energy management controller configured for performing at least one of the following operations based on the calculated energy required for operation of the mining haul truck:

(a) supplying power to the electric motor from the on-board energy storage system;

(b) charging the on-board energy storage system with power from a trolley power system;

(c) charging the on-board energy storage system with power generated by the electric motor during braking of the mining haul truck;

an inverter configured to:

receiving power from the on-board electrical energy storage system,

receiving power from the trolley power system, an

Supplying power to the motor; and

wherein the energy management controller is configured to propel the mining haul truck via electrical power supplied by at least one of the trolley power system alone, the on-board energy storage system alone, or a combination of the trolley power system and the on-board energy storage system, without mechanical power supplied by a mechanical engine.

10. The power system of claim 9, wherein the required energy is calculated based on a haul profile and a payload state of the mining haul truck.

11. The power system of claim 10, wherein the transportation profile comprises a distance, a slope of a floor, and a travel path.

12. The power system of any of claims 9 to 11, wherein:

the on-board energy storage system includes at least one ultracapacitor.

13. The power system of any of claims 9 to 11, wherein:

the on-board energy storage system includes at least one battery.

14. The power system of any of claims 9-11, wherein the energy management controller is further configured to:

supplying power to the motor from the trolley power system and/or charging the on-board energy storage system with power from the trolley power system when the mining haul truck is coupled to trolley lines of the trolley power system.

15. The power system of claim 14, wherein the energy management controller is further configured to:

supplying power to the electric motor from the on-board energy storage system when the mining haul truck is decoupled from the trolley line.

16. The power system of claim 14, wherein the energy management controller is further configured to:

after the onboard energy storage system is fully charged with power generated by the electric motor during braking of the mining haul truck, the power generated by the electric motor is returned to a utility grid via the trolley line.

17. A computer-readable storage medium, on which a computer program is stored which, when being executed by a processor, performs a method for supplying power to electric motors on all electrically driven mining haul trucks, wherein the mining haul trucks are equipped with an on-board energy storage system, and the method comprises the steps of:

calculating energy required for a mining haul drive operation and performing at least one of the following:

(a) supplying power to the electric motor from the on-board energy storage system;

(b) charging the on-board energy storage system with power from a trolley power system;

(c) charging the on-board energy storage system with power generated by the electric motor during braking of the mining haul truck;

propelling the mining haul truck with electrical power supplied by the trolley power system alone, or by the on-board energy storage system alone, or by a combination of the trolley power system and the on-board energy storage system, without mechanical power supplied by a mechanical engine.

18. The computer-readable storage medium of claim 17, wherein the required energy is calculated based on a haul profile and a payload state of the mining haul truck.

19. The computer-readable storage medium of claim 18, wherein the shipping profile includes a distance, a slope of a floor, and a travel path.

20. The computer readable storage medium of any of claims 17 to 19, wherein the electric motor is supplied with power from the trolley power system and/or the on-board energy storage system is charged with power from the trolley power system when the mining haul truck is coupled to a trolley line of the trolley power system.

21. The computer readable storage medium of claim 20, wherein the electric motor is supplied with power from the on-board energy storage system when the mining haul truck is decoupled from the trolley line.

22. The method of claim 20, wherein the power generated by the electric motor is returned to a utility grid via the trolley line after the onboard energy storage system is fully charged with the power generated by the electric motor during braking of the mining haul truck.

23. A method for operating an all-electric drive mining haul truck, the mining haul truck including an electric motor and an on-board energy storage system, the method comprising:

calculating energy required for mining haul truck operation and performing at least one of the following:

(a) supplying power to the electric motor from the on-board energy storage system;

(b) charging the on-board energy storage system with power from a trolley power system;

(c) charging the on-board energy storage system with power generated by the electric motor during braking of the mining haul truck;

driving the mining haul truck to a loading site; and

filling the mining haul truck with a payload;

wherein the mining haul truck is propelled by electrical power supplied by the trolley power system alone, or by the on-board energy storage system alone, or by a combination of the trolley power system and the on-board energy storage system, without mechanical power supplied by a mechanical engine.

24. The method of claim 23, wherein the required energy is calculated based on a haul profile and a payload state of the mining haul truck.

25. The method of claim 24, wherein the shipping profile includes distance, slope of the floor, and travel path.

26. The method of any one of claims 23 to 25, wherein:

the on-board energy storage system includes at least one ultracapacitor.

27. The method of any one of claims 23 to 25, wherein:

the on-board energy storage system includes at least one battery.

28. The method of any of claims 23 to 25, further comprising:

driving the mining haul truck to a skid steer incline;

coupling the mining haul truck to a trolley line of the trolley power system;

supplying power to the motor from the trolley power system;

driving the mining haul truck along the trolley ramp; and/or

Charging the on-board energy storage system with power from the trolley power system.

29. The method of claim 28, further comprising:

decoupling the mining haul truck from the trolley line;

supplying power to the electric motor from the on-board energy storage system.

30. The method of any of claims 23 to 25, further comprising:

driving the mining haul truck to an unloading site; and

unloading the payload from the mining haul truck.

31. The method of claim 28, further comprising:

after the onboard energy storage system is fully charged with power generated by the electric motor during braking of the mining haul truck, the power generated by the electric motor is returned to a utility grid via the trolley line.

Technical Field

The present invention relates generally to electrical power (power) systems for mining haul trucks, and more particularly to a system and method for all electrical operations of a mining haul truck.

Background

Mining haul trucks are typically equipped with an electrically driven engine. Under conditions of high demand, such as traveling on an uphill grade, power may be supplied through a trolley line. Mining haul trucks draw power from trolley lines via pantographs (pantographs). However, under certain travel conditions, such as inside the mining pit, around the crusher, and on the horizontal plane, the mining haul truck operates independently of the trolley line. The electrical power is then supplied by a generator powered by a diesel engine. Diesel engines require the delivery and storage of a fuel supply and require regular maintenance. In addition, exhaust gas from diesel engines contributes to air pollution.

Disclosure of Invention

In an embodiment of the invention, the mining haul truck driven by the electric motor is operated from all sources of electric power without the need for a diesel engine driving an electric generator. When the mining haul truck is traveling on substantially flat ground, electrical power is supplied by the on-board energy storage system. When the mining haul truck is traveling along an uphill grade, power is supplied through trolley lines. The onboard energy storage system is also charged with power from the trolley line. In an embodiment of the invention, the on-board energy storage system is charged with deceleration energy captured from the electric motor during braking.

These and other advantages of the present invention will be apparent to those of ordinary skill in the art by reference to the following detailed description and the accompanying drawings.

Drawings

Fig. 1 shows a single line diagram of a prior art diesel powered electrical system for a mining haul truck;

FIG. 2 shows a single line diagram of a prior art trolley power system for a mining haul truck;

fig. 3 shows a schematic view of a first travel scenario for a mining haul truck;

fig. 4 shows a schematic view of a second travel scenario for a mining haul truck;

fig. 5A and 5B show a flow chart of a process for all electrical operations of a mining haul truck;

FIG. 6 shows a schematic diagram of a power system with an ultracapacitor energy storage system;

FIG. 7 shows a plot of vehicle speed as a function of travel time and a plot of vehicle acceleration as a function of travel time;

FIG. 8 shows a plot of vehicle traction as a function of travel time and a plot of vehicle driving resistance as a function of travel time;

FIG. 9 shows a graph of travel distance as a function of travel time; and

fig. 10 shows a schematic diagram of an ultracapacitor energy management controller.

Detailed Description

Fig. 1 shows a single line diagram of a prior art mining haul truck power system. The mining haul truck has two drive wheels. Each wheel is driven by a 3-phase Alternating Current (AC) wheel motor (M). Wheel motors (wheel motors) are noted as wheel motor 110 and wheel motor 114. The power is supplied by a diesel engine 102 driving a 3-phase AC generator (G) 104. (other types of mechanical engines may be used; diesel engines are typical in mining operations.) a coupler 124 couples the diesel engine 102 to the generator 104. The diesel engine 102 and the generator 104 are mounted on a mining haul truck. The AC output of the generator 104 is fed into a rectifier 106. The Direct Current (DC) output of the rectifier 106 is fed into a set of inverters. The inverter 108 supplies 3-phase AC power to the wheel motor 110. Similarly, the inverter 112 supplies 3-phase AC power to the wheel motor 114. Chopper (chopper) 116 and power resistor grid 118 dissipate energy from wheel motors 110 during braking actions. Similarly, chopper 120 and power resistor grid 122 dissipate energy from wheel motors 114 during braking actions. The braking action is described in more detail below.

In the power system shown in fig. 1, all of the power requirements for the wheel motors 110 and 114 are supplied by the diesel engine 102. The performance of a mining haul truck (as determined, for example, by acceleration and speed) is limited by the electrical capacity of the diesel engine. In particular, when a mining haul truck filled with a heavy payload (payload) is traveling along an uphill grade, the diesel engine may be pressurized to a maximum capacity. One method for reducing the power demand on diesel engines when mining haul trucks are traveling on uphill grades is to power the wheel motors entirely via power drawn from trolley lines. During this mode of operation, the generator 104 is disconnected from the diesel engine 102 via the coupler 124. The diesel engine then idles on the uphill grade. As a result, fuel consumption is reduced by 95%; noise and exhaust emissions are reduced; and productivity and engine life increase.

Fig. 2 shows a single line diagram of a prior art mining haul truck power system including an overhead trolley power system. Similar to the power system shown in fig. 1, a diesel engine 202 is connected to a 3-phase AC generator 206 via a coupler 204. The AC output of the generator 206 is fed into a rectifier 208. The DC output of the rectifier 208 is fed into an inverter 210 that provides power to a wheel motor 212 and into an inverter 218 that provides power to a wheel motor 220.

The inputs of inverter 210 and inverter 218 may also be connected to DC power supplied by substation 250 via trolley lines 230 and 232. Trolley lines are also known as overhead lines. Electrical connections of the mining haul truck to trolley line 230 and trolley line 232 are made via pantograph arm 234 and pantograph arm 236, respectively. A throw switch (throw switch) 240 connects/disconnects the input terminals of the inverter 210 and the inverter 218 with/from the trolley line 230 and the trolley line 232. There is also an auxiliary breaker 238. As mentioned above, when the mining haul truck is powered by the trolley power system, the diesel engine 202 is typically disconnected from the generator 206 via the coupler 204.

Figure 3 shows a mining site with a loading site on a downhill slope from an unloading site; for example, the loading site is at the bottom of the pit and the payload is transported out of the pit by a truck. The loading bay 309 is located within the area 321. Within the area 321, the mining haul truck 302 is not powered by trolley lines. A discharge yard 339 is located within the area 351. Within the region 351, the mining haul truck 302 is not powered by trolley lines. Typically, the terrain in region 321 and in region 351 is substantially flat.

In the uphill direction, region 321 and region 351 are connected by a trolley ramp 371, along which trolley ramp 371 power is available from trolley line 370 (trolley line 370 refers to a pair of trolley lines for simplicity). In the downhill direction, region 351 and region 321 are connected by a trolley ramp 361, along which trolley ramp 361 power is available from trolley line 360. The trolley wire 370 and the trolley wire 360 are supported overhead by the support arm 312 fitted to the support bar 310.

In an embodiment of the present invention, the mining haul truck is equipped with an on-board energy storage system (OBESS) that provides electrical power when the mining haul truck is operating within region 321 or within region 351. No diesel engine and generator are required. The obass refers to an energy storage system that travels with a mining haul truck (e.g., mounted on, attached to, or mounted on a trailer attached to the mining haul truck). In embodiments of the present invention, the OBESS includes a supercapacitor bank, a battery bank, or both. Further details of the OBESS are provided below. First all the electrical operation of the mining haul truck is described.

Reference is made to the travel scenario shown in fig. 3. Powered by the OBESS, the mining haul truck 302 is launched in region 321 at position P301 and moved to the loading site 309. At the loading site 309, an electric shovel (not shown) fills a payload 304 (such as ore) onto the mining haul truck 302, which mining haul truck 302 then exits the loading site 309 at position P303. The mining haul truck 302 then moves to position P305 for access to the sliding ramp 371. Mining haul truck 302 is coupled to trolley line 370. Under trolley power (trolley power refers to power drawn from trolley lines), mining haul truck 302 moves up trolley ramp 371 (shown as position P373), and reaches position P331. When the mining haul truck 302 is coupled to the trolley line 370, the trolley power is used to recharge the OBESS.

Position P331 is an exit for sliding the ramp 371. The mining haul truck 302 is then decoupled from the trolley line 370. Powered by the OBESS, the mining haul truck 302 travels to location P333 and then to the unloading yard 339 where the mining haul truck 302 unloads the payload 304. The mining haul truck then exits the unloading site 339 at position P335 and moves to position P337 for entry to the skid ramp 361. The mining haul truck 302 is coupled to a trolley line 360. Under trolley power, the mining haul truck 302 moves down the trolley ramp 361 (shown as position P363), and reaches position P307. When the mining haul truck 302 is coupled to the trolley line 360, the trolley power is used to recharge the OBESS.

Position 307 is an exit for sliding ramp 361. The mining haul truck 302 is then decoupled from the trolley line 360. Powered by the OBESS, the mining haul truck 302 moves to position P301 to begin another work cycle.

Referring to the travel scenario illustrated in fig. 4, a mining site is illustrated with a loading site at an uphill slope of a self-unloading site. The loading site 409 is located within the area 421. Within the area 421, the mining haul truck 302 is not powered by trolley lines. The unloading bay 439 is located within the area 451. Within the area 451, the mining haul truck 302 is not powered by trolley lines. Typically, the terrain in area 421 and in area 451 is substantially flat.

In the uphill direction, zone 451 and zone 421 are connected by a trolley ramp 471, along which trolley ramp 471 trolley power is derived from trolley line 470. In the downhill direction, region 421 and region 451 are connected by a trolley ramp 461, along which trolley ramp 461 trolley power is available from trolley line 460. The trolley wire 470 and 460 are supported in an overhead manner by the support arm 412 mounted on the support bar 410.

Powered by the OBESS, the mining haul truck 302 starts in region 421, at position P401, and moves to the loading site 409. At the loading yard 409, an electric shovel (not shown) fills a payload 404 (such as ore) onto the mining haul truck 302, which mining haul truck 302 then exits the loading yard 409 at a location P403. Mining haul truck 302 then moves to position P405 for sliding access to ramp 461. The mining haul truck 302 is coupled to a trolley line 460. Under trolley power, the mining haul truck 302 moves down the trolley ramp 461 (shown as position P463) and reaches position P431. When the mining haul truck 302 is coupled to the trolley line 460, the trolley power is used to recharge the OBESS.

Position P431 is an exit for sliding the ramp 461. The mining haul truck 302 is then decoupled from the trolley line 460. Powered by the OBESS, the mining haul truck 302 travels to location P433 and then to the unloading yard 439 where the mining haul truck 302 unloads the payload 404. The mining haul truck 302 then exits the unloading lot 439 at position P435 and moves to position P437 for entry into the skid ramp 471. Mining haul truck 302 is coupled to trolley line 470. Under trolley power, the mining haul truck 302 moves up the trolley ramp 471 (shown as position P473) and reaches position P407. When the mining haul truck 302 is coupled to the trolley line 470, the trolley power is used to recharge the OBESS.

Position P407 is the exit for sliding contact ramp 471. The mining haul truck 302 is then decoupled from the trolley line 470. Powered by the OBESS, the mining haul truck 302 moves to position P401 to begin another work cycle.

The method for all electrical operation of the mining haul truck is summarized in the flow charts of fig. 5A and 5B. In step 502, a mining haul truck is started in region 1. In step 504, an on-board energy storage system (OBESS) is initially charged from an available power source, such as a charging station, a trolley line, or a diesel and generator. At step 506, powered by the OBESS, the mining haul truck travels within region 1 (e.g., to a loading site and receives a payload). In step 508, the mining haul truck travels to the trolley ramp 1, powered by the OBESS.

In step 510, a mining haul truck is coupled to trolley line 1. In step 512, the mining haul truck exits area 1 powered by trolley line 1. In step 514, power is supplied through trolley line 1 and the mining haul truck travels along trolley ramp 1. The OBESS is charged by the power from the trolley wire 1. In step 516, the mining haul truck arrives at area 2 powered through trolley line 1.

In step 518, the mining haul truck is decoupled from the trolley line 1. In step 520, powered by the OBESS, the mining haul truck travels within region 2 (e.g., to an unloading site and dumps the payload). In step 522, powered by the OBESS, the mining haul truck travels to the trolley ramp 2.

In step 524, the mining haul truck is coupled to the trolley line 2. In step 526, the mining haul truck exits area 2 powered by trolley line 2. In step 528, the mining haul truck travels along the trolley ramp 2, powered by the trolley line 2. The OBESS is charged by the power from the trolley wire 2. In step 530, the mining haul truck arrives at area 1 powered through trolley line 2. In step 532, the mining haul truck is decoupled from the trolley line 2. The mining haul truck has an OBESS charged and is ready to begin another work cycle.

In an embodiment of the present invention, the OBESS is charged with deceleration energy from the wheel motors. To slow down the moving mining haul truck, the mining haul truck drive system operates in a deceleration mode. Under normal operation, the electric motor converts electrical energy into mechanical energy. The operating mode in which the electric motor converts electric energy into mechanical energy is referred to as a propulsion mode, and the time interval during which the electric motor operates in the propulsion mode is referred to as a propulsion interval. The electric motor may instead operate as a generator to convert mechanical energy into electrical energy (referred to as retarding energy) that is fed into the inverter. The operation mode in which the electric motor converts mechanical energy into electrical energy is referred to as a deceleration mode, and the time interval during which the electric motor operates in the deceleration mode is referred to as a deceleration interval.

Typically, a brake chopper connected to an inverter directs power into a power resistor grid that continuously dissipates retarding energy until the mining haul truck comes to a stop; that is, the deceleration energy is dissipated as waste heat. The braking is smooth, similar to the braking operation in a car, but without mechanical brake wear. For example, refer to the prior art power system shown in fig. 2. Chopper 214 and power resistor grid 216 provide a braking action for wheel motor 212. Similarly, chopper 222 and power resistor grid 224 provide a braking action for wheel motor 220.

However, in embodiments of the present invention, the OBESS is integrated into the mining haul truck power system to recapture and store retarding energy. In particular, when the mining haul truck is traveling downhill, a significant amount of deceleration energy may be captured and stored (especially if the mining haul truck is carrying a payload of a load) because the mining haul truck is frequently braked and, therefore, there are frequent intervals during which the wheel motors are operating in a deceleration mode. Depending on the terrain, deceleration energy may also be captured during an uphill trip; deceleration energy may also be captured while the mining haul truck is traveling on level ground.

The deceleration energy is then used to charge the OBESS. In an embodiment of the present invention, the OBESS is implemented with an ultracapacitor system comprising an ultracapacitor bank. The amount of energy that can be stored in the ultracapacitor system depends on the size of the ultracapacitor bank. The OBESS may also be implemented with a rechargeable battery system including a battery pack. The amount of energy that can be stored in the battery system depends on the size of the battery pack. The OBESS may also be implemented with a combination of a supercapacitor bank and a battery bank. The storage capacity requirements are described below.

Supercapacitors can provide high power density. For increased electrical energy storage, a plurality of ultracapacitors may be connected in series and parallel to form an ultracapacitor bank. The current flowing into the supercapacitor charges the supercapacitor, and electrical energy is stored via charge separation at the electrode-electrolyte interface. The stored electrical energy may then be used later to output electrical current. To maximize the lifetime of the supercapacitor, the supercapacitor is not fully discharged. Typically, the supercapacitor discharges until its voltage drops to a minimum user-defined lower voltage limit. For example, the lower voltage limit may be half of the voltage that is initially fully charged.

Fig. 6 shows a schematic diagram of an OBESS 626 integrated into a trolley power system. The wheel motors 610 are powered by an engine drive system 630, the engine drive system 630 including a DC link capacitor 606 and an inverter 608. The trolley DC power system 604 provides DC power to the engine drive system 630 via trolley lines. In the example shown, the OBESS 626 includes a supercapacitor electrical energy storage unit 614 and a supercapacitor energy management controller 612. The ultracapacitor electrical energy storage unit 614 includes a DC-to-DC converter 618, a choke/reactor 622, and an ultracapacitor bank 624. The ultracapacitor electrical energy storage unit 614 may be disconnected from the engine drive system 630 via a connect/disconnect switch 616.

The ultracapacitor electrical energy storage unit 614 is managed by the ultracapacitor energy management controller 612. The ultracapacitor energy management controller 612 may also receive engine drive system data 628 that characterizes the operation of the engine drive system 630. For example, the engine drive system data 628 includes DC link voltage, current, and temperature. In response to control signals or control commands from the ultracapacitor energy management controller 612, the ultracapacitor electrical energy storage unit 614 may: (a) transmit power to the wheel motors, (b) receive power from the trolley DC power system, or (c) receive retard power from the wheel motors. If the supercapacitor bank becomes fully charged, excess retarding energy may be dissipated in the grid resistor. Excess retard energy may also be transmitted via trolley lines and stored in the auxiliary energy storage system, or transmitted via trolley lines and returned to the utility grid via a bidirectional substation (as described in U.S. patent application publication No. 2011/0094841).

An embodiment of a computing system for implementing the ultracapacitor energy management controller 612 (fig. 6) is shown in fig. 10. The computing system 1002 is typically located in a mining haul truck; however, other locations are possible. Computing system 1002 may be constructed from various combinations of hardware, firmware, and software by those skilled in the art. Computing system 1002 may be constructed from various electronic components including one or more general purpose processors (such as a microprocessor), one or more digital signal processors, one or more Application Specific Integrated Circuits (ASICs), and one or more Field Programmable Gate Arrays (FPGAs).

The computing system 1002 includes a computer 1006, the computer 1006 including a processor, referred to as a Central Processing Unit (CPU) 1008, memory 1010 and data storage 1012. The data storage device 1012 includes at least one persistent, tangible computer-readable medium, such as non-volatile semiconductor memory, magnetic hard drives, and optical disk read-only memory. In an embodiment of the invention, the computer 1006 is implemented as an integrated device.

The computing system 1002 may further include a user input/output interface 1014 that interfaces the computer 1006 to a user input/output device 1022. Examples of input/output devices 1022 include a keyboard, a mouse, and a local access terminal. Data, including computer executable code, may be transferred to and from the computer 1006 via the input/output interface 1014.

The computing system 1002 may further include a communication network interface 1016, the communication network interface 1016 interfacing the computer 1006 with a remote access network 1024. Examples of remote access networks 1024 include local area networks and wide area networks (communication links may be wireless). A user may access computer 1006 via a remote access terminal (not shown). Data, including computer executable code, may be transferred to and from computer 1006 via a communication network interface 1016.

The computing system 1002 may further include an ultracapacitor power storage unit interface 1018 that interfaces the computer 1006 with the ultracapacitor power storage unit 614 (see fig. 6). The computing system 1002 may further include an engine-driven system interface 1020, the engine-driven system interface 1020 interfacing the computer 1006 with an engine-driven system 630 (see fig. 6). The engine drive system interface 1020 receives, for example, engine drive system data 628.

As is well known, computers operate under the control of computer software that defines the overall operation and application of the computer. The CPU 1008 controls the overall operation and application of the computer by executing computer program instructions that define the overall operation and application. The computer program instructions may be stored in the data storage device 1012 and loaded into the memory 1010 when execution of the program instructions is desired.

The method steps shown in the flow diagrams in fig. 5A and 5B may be defined by computer program instructions stored in memory 1010 or in data storage device 1012 (or in a combination of memory 1010 and data storage device 1012), and controlled by CPU 1008 executing the computer program instructions. For example, the computer program instructions may be implemented as computer executable code programmed by one skilled in the art to perform an algorithm that implements the method steps shown in the flow charts in fig. 5A and 5B. Thus, by executing the computer program instructions, the CPU 1008 executes an algorithm that implements the method steps shown in the flow charts in fig. 5A and 5B.

The required OBESS storage capacity can be estimated from the calculations. For example, assume the following shipping profile (a travel scenario similar to the one shown in FIG. 3):

500m, flat: shoveled (loaded) onto sliding slopes, loaded

2000m, 10% slope: sliding-contact ramps, loaded

500m, flat: sliding on a slope to a dump site (unloading site), loaded

500m, flat: dumping grounds to sliding slopes, empty

2000m, -10% grade: sliding on a slope, empty

500m, flat: slide the ramp to the shovel, empty.

Each branch of the profile specifies: (a) distance traveled, (b) slope of the ground, (c) path of travel, and (d) payload status of the mining haul truck. The weight of the empty mining haul truck is assumed to be 160,000 kg; and the weight of the loaded mining haul truck is assumed to be 400,000 kg.

The speed and acceleration for a mining haul truck operating on the above profile is shown in fig. 7. The curve 702 shows vehicle speed (km/hr) as a function of travel time(s). Curve 704 relates vehicle acceleration (m/s)²) Shown as a function of travel time(s). Refer to fig. 8. Curve 802 shows vehicle tractive effort (kN) as a function of travel time(s). Curve 804 shows the vehicle driving resistance (kN) as a function of travel time(s). Refer to fig. 9. Curve 902 shows the travel distance (m) as a function of travel time(s).

As can be seen in fig. 7: mining haul trucks require approximately 50 seconds to reach the trolley ramp. Similarly, it will take about the same time to travel from the slipover ramp to the dump site (unloading yard). Returning from the dump site to the trolley ramp will require less time because the mining haul truck is empty. The mining haul truck requires approximately 24kWh of energy from the OBESS to move the mining haul truck from the shovel (loading bay) to the trolley ramp. The energy required from the OBESS will be equal to or less than 24kWh for all other regions.

The selection of an appropriate energy storage device is important. Mines are often located in remote locations with extreme climatic conditions. Extremely cold conditions with temperatures below-20 ℃ pose particular challenges. In addition, mining haul trucks are subject to extreme shock and vibration. Suitable candidates for energy storage are traction stage supercapacitors and traction stage batteries.

Reference is made back to the travel scenario shown in fig. 3 and in fig. 4. The trolley power is supplied on both the uphill and downhill paths. In some scenarios, if the OBESS is sufficiently charged at the beginning of the downhill path, and if sufficient deceleration energy is generated along the downhill path to maintain sufficient charging in the OBESS for the mining haul truck to operate along the entirety of the downhill path and within the downhill region (region 321 in fig. 3 or region 451 in fig. 4) when powered by the OBESS, no trolley power is required on the downhill path.

Embodiments of the present invention can be retrofitted into existing mining haul trucks having diesel engines and generators. The diesel engine may be reserved for operation in fault conditions or for charging the OBESS when idle. In other embodiments of the invention, the mining haul truck is not equipped with a diesel engine and generator: the mining haul truck is propelled by electrical power supplied by trolley lines alone, OBESS alone, or a combination of trolley lines and OBESS.

Embodiments of the present invention have been described with reference to mining haul trucks. Those skilled in the art may develop embodiments of the present invention for use with other vehicles that are driven by an electric motor.

The foregoing detailed description is to be understood as being in every respect illustrative and exemplary, but not restrictive, and the scope of the invention disclosed herein is not to be determined from the detailed description, but rather from the claims as interpreted according to the full breadth permitted by the patent laws. It is to be understood that: the embodiments shown and described herein are merely illustrative of the principles of the invention and various modifications can be made by those skilled in the art without departing from the scope and spirit of the invention. Various other combinations of features may be implemented by those skilled in the art without departing from the scope and spirit of the invention.