FI131018B1

FI131018B1 - Power system in a mining machine

Info

Publication number: FI131018B1
Application number: FI20205455A
Authority: FI
Inventors: Emil Andersson
Original assignee: Epiroc Rock Drills Ab
Priority date: 2017-11-06
Filing date: 2018-10-25
Publication date: 2024-08-02
Also published as: ZA202000966B; WO2019088900A1; AU2018359331A1; FI20205455A; SE541361C2; SE1751375A1; FI20205455A1; CA3073307A1

Abstract

The present disclosure relates to a power system (100) in a mining machine (10) configured to perform an at least partly stationary, high power operation driving one or more electrically powered tools (12) of the mining machine. The power system is arranged to provide electrical power to the one or more electrically powered tools. The power system comprises an energy storage system (120), an energy management system (130), and a distribution board (140). The energy storage system (120) comprises a plurality of exchangeable energy sources (122a-d) configured for recharging when detached from the mining machine. The distribution board (140) comprises a plurality of contactors (142a-d). One or more contactors are arranged to control a connection between the energy sources and the one or more electrically powered tools. The energy management system is configured to control operation of the distribution board. The present disclosure also relates to corresponding mining machines.

Description

Power System in a Mining Machine

TECHNICAL FIELD

The present disclosure relates to power systems in mining machines and mining machines.

BACKGROUND

During a planned cycle of mining operations, a number of different mining machines for mining and rock excavation, e.g. face drill rigs, production drill rigs, loaders, haulers, dumpers, rock bolting rigs, cable bolting rigs and concrete spraying machines, are involved in different phases of the mining operation. There is ongoing work in adapting these machines to operate using electricity, which offers advantages in that diesel exhaust fumes can be avoided and the need — for ventilation in the mine can thereby be reduced.

During stationary operational use, the local electric grid of the mine typically does not constitute a limitation to a mining machine currently at work. As the mining machine transfer drives between two places, commonly known as tramming, use of electric cables and the like may restrict the transfer drive. Document W02011/080392 discloses a solution wherein a built-in — battery is used to provide power during transfer drives of a mining machine.

The planned cycles are necessary to ensure both operational efficiency and safety. Any interruptions may have negative cascading effects on the stages and must necessarily be kept to a minimum. One type of interruption currently faced with mining machines operating at least partially with power from a battery is the interruption occurring when the battery needs

SQ 20 tobereplaced. Afurther problem associated with replacing the battery is the temporary impact

N on the centre of gravity on the mining machine; the change in centre of gravity during battery 3 exchange may increase the risk of problems with stability of the mining machine. Thus, there is 7 a need in the art for to address the problems associated with battery replacement in mining

E machines.

LÖ m 25 SUMMARY

S

& The problems of interruptions during battery replacement and the change in centre of gravity as the battery is removed is addressed by having a plurality of exchangeable energy sources and system for switching between the energy sources as needed. As one energy source gets depleted, the electrical connection between that energy source gets disconnected and an electrical connection is established to another energy source, which reduces the interruptions to the insignificant time it takes to switch between different electrical connections. Since the total available energy is distributed across several exchangeable energy sources, the removal of one energy source during exchange has a much smaller effect on the centre of gravity than a corresponding removal of all energy sources would have.

The present disclosure relates to a power system in a mining machine configured to perform an at least partly stationary, high power operation driving one or more electrically powered tools of the mining machine. The power system is arranged to provide electrical power to the one or — more electrically powered tools. The power system comprises an energy storage system, an energy management system, and a distribution board. The energy storage system comprises a plurality of exchangeable energy sources configured for recharging when detached from the mining machine. The distribution board comprises a plurality of contactors. One or more contactors are arranged to control a connection between the energy sources and the one or more electrically powered tools. The energy management system is configured to control operation of the distribution board.

The power system thereby separates the electrical power grid from directly powering the electrically powered tools. In particular, the power system enables recharging of energy sources not currently involved in the high power operation. Power load demand peaks on the electrical power grid can thereby be greatly reduced or eliminated. Conversely, the disclosed power system is able to provide a more stable electrical power source to the powered tools than a o direct connection to the electrical power grid. A further effect is that a plurality of, possibly

O different, mining machines configured to perform an at least partly stationary, high power 3 operation driving one or more electrically powered tools of the respective mining machine, can

S 25 be supported by the electrical power grid. If each mining machine were to use the electrical

E power grid to power a respective high power operation simultaneously, the electrical power 2 grid may not be able to provide the necessary electrical power; the disclosed power system 3 enables a reduction of the electrical power demand to recharging a plurality of batteries, which

S reguires a lower and more stable electrical power source. The power system further enables continuous operation since the distribution board enables immediate or overlapping reallocation of available energy sources; when some rechargeable energy sources are depleted,

they may be replaced by charged energy sources, e.g., fully charged rechargeable energy sources or energy sources charged to a desired level of charging, by a switch of one or more of the contactors. The depleted rechargeable energy sources may at the same time be detached and recharged.

According to some aspects, an exchangeable energy source is one of a rechargeable battery, a supercapacitor, a rechargeable fuel cell and a flywheel. These rechargeable energy sources enable sufficient energy storage with respect to weight and operational demands, while also being able to provide the necessary power output during discharge.

According to some aspects, one or more energy sources of the plurality of energy sources are detachably mounted on the mining machine. A single energy source, such as a single battery, may be cumbersome to replace, e.g., due to weight of the battery; a plurality of detachably mounted energy sources facilitates replacement and recharge, since the individual units can be made much smaller. Detachably mounting the energy sources on the mining machine further enables taking advantage of the weight of the batteries in order to stabilise the mining machine by mounting them on the mining machine. During battery exchange with a single energy source the centre of gravity may shift quite dramatically, which puts the mining machine at risk if it has not been sufficiently stabilized. A plurality of detachably mounted energy sources enables detaching smaller units one at a time, which translates to smaller impact on the centre of gravity during exchange of energy sources.

According to some aspects, one or more energy sources of the plurality of energy sources are mounted on a carrier separated from the mining machine. The one or more energy sources may

N thereby function as a power bank, and can also be shared with other devices or machines, e.g.

N other mining machines. <Q 3 According to some aspects, the plurality of exchangeable energy sources are rechargeable

E 25 — batteries mounted on the mining machine. The plurality of rechargeable batteries are mounted

O with a spatial distribution selected to achieve at least one of a predetermined centre of gravity 3 of the mining machine, ease of access to the plurality of exchangeable energy sources, providing

O a free field of rear vision for an operator of the mining machine and enable access to one or more auxiliary system of the mining machine. According to some further aspects, the plurality of exchangeable energy sources is mounted on the mining machine. The plurality of exchangeable batteries comprises at least a first and a second set of exchangeable batteries.

The first and second sets of exchangeable batteries are mounted at opposing sides of a centre line of the mining machine. Since passages in caves often are too narrow to enable mining machines to drive side by side, it is desirable to enable detachment of the batteries from a rear position of the mining machine. Having a large single battery at the rear may shift the centre of gravity too far back for the mining machine to achieve optimal stability during the at least partially stationary, high power operation. A plurality of batteries may be distributed along a longitudinal direction of the mining machine and thereby shift the centre of gravity towards a geometrical centre of the mining machine, possibly while still enabling at least some batteries to be accessed from the rear of the mining machine. Alternatively, or in combination, the batteries may be distributed at opposing sides of a centre line of the mining machine in order to balance torque, in particular during the high power operation. There is often a demand that the operator has to have an unobstructed view to the rear within a predetermined angular interval. Distributing a plurality of smaller batteries compared to a single, large battery facilitates meeting such demands.

The present disclosure also relates to a mining machine comprising one or more electrically powered tools, a machine control unit, and a power system arranged to provide electrical power to the one or more electrically powered tools. The mining machine further comprises a power system as described above and below. The mining machine becomes independent of the electrical power grid from directly powering the electrically powered tools. In particular, the power system of the mining machine enables recharging of energy sources not currently involved in the high power operation. Power load demand peaks on the electrical power grid

N can thereby be greatly reduced or eliminated. The mining machine can further operate

N uninterrupted since the distribution board enables immediate reallocation of available energy = 25 — sources; when some rechargeable energy sources are depleted, they may be replaced by fully 7 charged rechargeable energy sources by a switch of one or more of the contactors. The depleted : rechargeable energy sources may at the same time be taken away to be recharged and = exchanged for fully charged rechargeable energy sources.

S

S According to some aspects, the machine control unit is configured to store an operational plan for the high power operation. The machine control unit is further configured to obtain information relating to a respective electrical energy state of each energy source from the energy management system and to transmit control signals to the energy management system via a control signal interface of the energy management system. According to some further aspects, the stored operational plan comprises information relating to a power load demand having a temporal distribution. The operation of the power system can thereby be controlled 5 by an automatic control system of the mining machine. The mining machine, or an operator operating the mining machine, typically has more information relevant to the mining operations in question than the power system alone, and is therefore in a better position to make informed decisions on the best use of the exchangeable batteries. In particular, the availability of the operational plan enables improved electrical energy resource management, since the temporal distribution of the demand for electrical power can be taken into account.

According to some aspects, the control signals are configured to prevent each energy source engaged in providing electric power to the one or more electrically powered tools to fall below a predetermined electrical energy state threshold. The lifetime of rechargeable batteries can often be extended by operating the discharge-recharge cycles within a certain charge depletion range ofthe rechargeable batteries. By keeping the predetermined electrical energy state above a predetermined threshold, energy sources such as rechargeable batteries can be operated within a charge depletion range arranged to extend the lifetime of the rechargeable batteries.

According to some aspects, the mining machine is a drill rig. Drill rigs, such face drill rigs and production drill rigs, require particularly high peak powers during the at least partly stationary, — high power operation of drilling, and therefore benefit particularly well from the disclosed power system.

N BRIEF DESCRIPTION OF THE DRAWINGS

N ro Figure 1 illustrates a power system in a mining machine and a mining machine according to 3 the present disclosure; and

I

& 25 Figures 2a and 2b illustrate power systems in mining machines and mining machine according 3 to the present disclosure. £ o Figure 3 illustrates a mining machine and a power system in a mining machine according to the present disclosure.

DETAILED DESCRIPTION

Figure 1 illustrates a power system 100 in a mining machine and a mining machine 10 according to the present disclosure.

The mining machine 10 comprises one or more electrically powered tools 12, a machine control — unit 18, and a power system 100 arranged to provide electrical power to the one or more electrically powered tools. The mining machine 10 is configured to perform an at least partly stationary, high power operation driving the one or more electrically powered tools 12 of the mining machine 10. Mining machines such as loaders, haulers, dumpers, and concrete spraying machines may experience the need to perform an at least partly stationary, high power operation, and thus benefit from the disclosed power system. Bolting rigs, e.g., rock bolting rigs and cable bolting rigs, and drill rigs, e.g. face drill rigs and production drill rigs, mainly perform stationary high power operations and are thus particularly suitable for having a power system as described above and below. Thus, according to some aspects, the mining machine is a bolting rig or a drill rig.

The power system 100 is arranged to provide electrical power to the one or more electrically powered tools 12. The power system further comprises an energy storage system 120. The power system also comprises an energy management system 130. The energy management system 130 may be configured to monitor an operational status, e.g. an amount of stored energy, of the energy storage system 120.

The energy storage system 120 comprises a plurality of exchangeable energy sources 122a, o 122b, 122c, 122d configured for recharging when detached from the mining machine. According

O to some aspects, an exchangeable energy source 122a, 122b, 122c, 122d is one of a ro rechargeable battery, a supercapacitor, a rechargeable fuel cell and a flywheel.

S kai - The power system 100 yet further comprises a distribution board 140. The purpose of the & 25 — distribution board 140 is to provide electrical connections between the exchangeable energy 3 sources 122a, 122b, 122c, 122d and electrical systems and interfaces with which the

S rechargeable energy sources are intended to interact, in particular the one or more powered

N tools. The distribution board further comprises a plurality of contactors 142a, 142b, 142c, 142d.

A contactor is a switch used for switching an electrical power circuit. Contactors differ from generic relays in that they are particularly suitable for high voltage applications or high current applications, e.g., applications in a four hundred to a thousand Volt (V) range or up to 1500

Ampere (A) when applying lower voltages. The plurality of contactors enables different electrical connections between the energy storage system and electrically powered systems of the mining machine. Specifically, one or more contactors are arranged to control a connection between the energy sources and the one or more electrically powered tools. The energy management system 130 is configured to control operation of the distribution board 140. The above disclosed power system enable operation from the energy sources also during exchange, since the power system can switch from one exchangeable energy source providing the — necessary power for the high power operation to another exchangeable energy source by switching a set of contactors. Thus, the disclosed power system and mining machine can operate independent from the electrical power grid and the energy sources can be exchanged during operational use of the mining machine.

According to an aspect of the disclosure, the distribution board may also be used to enable recharging of one or more of the exchangeable energy sources 122a, 122b, 122c, 122d from a grid connection (not disclosed) also when mounted in the mining machine, i.e., enabling recharging of some of the energy sources in addition to exchange of the energy sources of the mining machine.

According to some aspects, one or more exchangeable energy sources of the plurality of exchangeable energy sources 122a, 122b, 122c, 122d are mounted on a carrier separated from the mining machine. The one or more exchangeable energy sources may thereby function as a o power bank, and can also be shared with other devices or machines, e.g. other mining machines.

S

N The following presentation will be directed to the embodiment of a rechargeable battery, but = this is merely used for explanatory purposes and does not limit the disclosure to the battery 7 25 embodiment. a a

O As explained above, the disclosed power system enable operation from battery power also 3 during battery exchange, since the power system can switch from one exchangeable battery

O providing the necessary power for the high power operation to another exchangeable battery by switching a set of contactors, thereby routing electrical power supplied by one battery to electrical power supplied by another battery. In other words, the disclosed power system and mining machine can operate independent from the electrical power grid and the energy sources can be exchanged during operational use of the mining machine. The disclosed power system and mining machine further enables greater stability during battery exchange as compared with exchanging a single, large battery. It is typically also less cumbersome to exchange several smaller and lighter batteries than it is to exchange a single, large and heavy battery. A yet further advantage is that possibilities for improved battery cycling is enabled by operating in a good state-of-charge range for the batteries, which leads to decreased tear of the battery.

According to some preferred aspects, one or more energy sources of the plurality of exchangeable energy sources 122a, 122b, 122c, 122d are detachably mounted on the mining machine. A single energy source, such as a single and heavy battery, is cumbersome to replace; a plurality of detachably mounted energy sources facilitates replacement and recharge, since the individual units can be made much smaller than a single, equivalent energy source.

Detachably mounting the energy sources on the mining machine further enables taking advantage of the weight of the batteries in order to stabilise the mining machine by mounting them on the mining machine. During battery exchange with a single energy source the centre of gravity may shift quite dramatically, which puts the mining machine at risk if it has not been sufficiently stabilized. A plurality of detachably mounted energy sources enables detaching smaller units one at a time, which translates to smaller impact on the centre of gravity during exchange of energy sources. — Since passages in caves often are too narrow to enable mining machines to drive side by side, it is desirable to enable detachment of the batteries from a rear position of the mining machine. o Having a large single battery at the rear may shift the centre of gravity too far back for the

O mining machine to achieve optimal stability during the at least partially stationary, high power 3 operation. A plurality of batteries may be distributed along a longitudinal direction of the mining 3 25 machine and thereby shift the centre of gravity towards a geometrical centre of the mining

E machine, possibly while still enabling at least some batteries to be accessed from the rear of the

O mining machine. There is often a demand that the operator has to have an unobstructed view 3 to the rear within a predetermined angular interval. Distributing a plurality of smaller batteries

S compared to a single, large battery facilitates meeting such demands. Additionally, when mounted, the rechargeable batteries may be used to provide electrical power to auxiliary systems 16 part of the mining machine and/or external devices, such as light towers, pumps,

supporting grid or other machines, e.g. other mining machines. Therefore, according to some aspects, the plurality of exchangeable energy sources are rechargeable batteries mounted on the mining machine. According to some aspects, one or more of the rechargeable batteries is configured to provide electrical power to a power train 14 of the mining machine. According to some aspects, the energy management system 130 further comprises an energy source management system 132 configured to retrieve operational data for each rechargeable battery, e.g., to determine an energy level of the rechargeable battery or to determine that a battery is in use in the operation performed by the mining machine. According to some aspects, the energy source management system 132 comprises one or more battery management systems,

BMS. According to some further aspects, each rechargeable battery comprises a respective

BMS. The plurality of rechargeable batteries are mounted with a spatial distribution selected to achieve at least one of a predetermined centre of gravity of the mining machine, ease of access to the plurality of exchangeable energy sources, providing a free field of rear vision for an operator of the mining machine and enable access to one or more auxiliary systems 16 of the mining machine. Alternatively, or in combination with the distributions described above, the batteries may be distributed at opposing sides of a centre line of the mining machine in order to balance torque, in particular during the high power operation. In other words, according to some aspects, the plurality of exchangeable batteries is mounted on the mining machine. The plurality of exchangeable batteries comprises at least a first and a second set of exchangeable batteries, and the first and second set of exchangeable batteries are mounted at opposing sides of a centre line of the mining machine.

Since not all of the plurality of exchangeable batteries may be directly accessible from the rear

N of the mining machine, it is desirable to facilitate exchange from the rear of the mining machine

N also for such batteries. Therefore, according to some aspects, the mining machine comprises = 25 one or more actuators arranged to move one or more of the plurality of exchangeable batteries 2 along a longitudinal direction of the mining machine. Batteries closer to the centre of the mining so machine can thereby be moved towards the rear. Sometimes direct rearward movement is = blocked or undesirable. The one or more batteries to be moved may thus be arranged to move

N in a transverse or horizontal direction in order to provide a free path to the rear of the mining

N 30 machine. Thus, the one or more actuators may further be arranged to move the one or more of the plurality of exchangeable batteries along direction perpendicular to the longitudinal direction of the mining machine.

Alternatively, or in combination with the one or more actuators, the mining machine comprises a mount crane configured to provide assistance during battery exchange. This eliminates the need for adapted assist vehicles and/or installations.

According to some aspects, the energy management system 130 comprises a control signal interface 134 configured to receive control signals from the machine control unit 18 of the mining machine 10. The energy management system 130 is further configured to control operation of the distribution board 140 based on control signals received from the machine — control unit 18. The machine control unit 18 typically comprises a processor and a memory, thereby enabling the machine control unit 18 to automate the operation of the power system 100. Since the memory of the machine control unit may store information relating to information of the mining machine and its intended use, in particular information relating to an operational plan, the machine control unit is in a better position than the energy management system to determine how to optimally charge and discharge electrical energy to and from the rechargeable batteries.

Therefore, according to some aspects, the machine control unit is configured to store an operational plan for the high power operation. The machine control unit is further configured to obtain information relating to a respective electrical energy state of each energy source from the energy management system and to transmit control signals to the energy management system via the control signal interface of the energy management system. In other words,

N according to some aspects, the control signals received by the energy management system of

N the power system are based on an operational plan for the high power operation and = information relating to a respective electrical energy state of each rechargeable battery. 7 25 According to some further aspects, the stored operational plan comprises information relating

S to a power load demand having a temporal distribution. The machine control unit is preferably

E configured to analyse the power load demand of the operational plan and the information

N relating the respective electrical energy states of the rechargeable batteries to generate the

N control signals automatically. As stated above, improved battery cycling is enabled by operating in a good state-of-charge range for the batteries. Thus, according to some aspects, the control signals are configured to prevent each energy source engaged in providing electric power to the one or more electrically powered tools to fall below a predetermined electrical energy state threshold.

Figures 2a and 2b illustrate mining machines 20a, 20b and power systems 200a, 200b according to the present disclosure. The figures aim to illustrate different ways of distributing the exchangeable energy sources 222a-d and the associated advantages. The exchangeable energy sources 222a-d will be exemplified with rechargeable batteries, but all technical features illustrated in relation to Figure 1 above may be included freely into the aspects illustrated in

Figures 2a and 2b, and vice versa. — Each mining machine 20a, 20b comprises one or more electrically powered tools 22. Each mining machine further comprises a machine control unit 28. Each mining machine also comprises a power system 200a, 200b arranged to provide electrical power to the one or more electrically powered tools 22. Each mining machine 20a, 20b is configured to perform an at least partly stationary, high power operation driving the one or more electrically powered tools 22.

According to some preferred aspects, the mining machines are drill rigs, e.g. face drill rigs or production drill rigs.

Each power system 200a, 200b is arranged to provide electrical power to the one or more electrically powered tools. Each power system comprises an energy storage system, an energy management system 230, and a distribution board 240. The energy storage systems each comprise a plurality of exchangeable energy sources 222a-d configured for recharging when detached from the respective mining machine 20a, 20b. Each distribution board 240 comprises

N a plurality of contactors, wherein one or more contactors are arranged to control a connection

N between the energy sources and the one or more electrically powered tools. Each energy = management system is configured to control operation of a respective distribution board.

O

E 25 The plurality of exchangeable energy sources comprises rechargeable batteries mounted on the

O respective mining machines. The rechargeable batteries are mounted with a spatial distribution 3 selected to achieve a predetermined centre of gravity of the mining machine. In both Figure 2a

O and 2b, the rechargeable batteries are distributed parallel to a centre line of the mining machine, thereby shifting the centre of gravity towards a centre position of the respective mining machine. The resulting centre of gravity is thus arranged at a position that makes the mining machines more stable compared to solutions having a single and heavy battery at the rear of the mining machines.

In Figure 2a, the plurality of exchangeable batteries 222a-d comprises at least a first 222a, 222c and a second set 222b, 222d of exchangeable batteries. The first and second sets of exchangeable batteries are mounted at opposing sides of a centre line of the mining machine.

During a stationary, high power operation, such as drilling, the mining machines are often fixated to the surroundings of the mine in order to stabilize the mining machines. Powerful vibrations cause unwanted perturbations in the centre of gravity of the mining machines. By mounting the first and second set of exchangeable batteries at opposing sides of a centre line of the respective mining machines, the moment of inertia may be both balanced and increased about the centre line, thereby improving stability, and hence safety, of the mining machine during the high power operation.

In Figure 2b, the exchangeable batteries 222a-c are mounted on the mining machine in one or more rows. By positioning the exchangeable batteries in rows, they are easier to access from the rear during exchange.

In each example, at least a subset of the exchangeable batteries is arranged close to the rear of the mining machine, thereby facilitating exchange in narrow spaces.

Battery exchange can be further facilitated in the illustrated mining machines by providing the mining machines with systems arranged to support exchange. For instance, the mining machines may comprise a mount crane configured to provide assistance during battery o exchange, which eliminates the need for adapted assist vehicles and/or installations. According

O to some aspects, the mining machines further comprises a set of actuators configured to move ro one or more of the exchangeable energy sources to the rear end of the machine, as described 3 above in relation to Fig.1. The actuators may be hydraulic actuators and/or electrical actuators,

E 25 e.g. electric motors. Having the batteries arranged in rows, as illustrated in Figure 2b typically

O reduces the complexity of such an actuator system.

D

S

&

Figure 3 illustrates a mining machine 30 and a power system 300 in a mining machine according to the present disclosure. Figure 3 aims at further illustrating how the electrically powered tools may be driven by the power system, in particular the use of electric motors, as well as illustrating some additional devices that will often appear in concert with the disclosed power system and mining machine, such as fuses and inverters. The mining machine comprises one or more electrically powered tools 32, a machine control unit 38, and a power system configured to provide electrical power to the one or more electrically powered tools 32. The mining machine 30 is here illustrated as a drill rig. The one or more electrically powered tools is illustrated as a hydraulic pump drilling system 32, wherein the drill itself (not shown) is driven by one or more electric motors 35 and the positioning of the drill as well as the pressure of the drill against the rock is controlled by the hydraulics of the hydraulic pump drilling system 32. Drilling is typically — performed stationary, wherein the mining machine has been stabilized with respect to the environment, and reguires high power to break the rock that is being drilled. In other words, the mining machine is configured to perform an at least partly stationary, high power operation driving the one or more electrically powered tools.

The power system is configured to provide electrical power to the one or more electrically powered tools. The power system 300 comprises an energy storage system and a distribution board 340. The energy storage system comprises a plurality of exchangeable energy sources configured for recharging when detached from the mining machine, here illustrated as a pair of rechargeable batteries 322a, 322b mounted at opposing sides of a centre line of the mining machine 30.

The distribution board 340 comprises a plurality of contactors 342a-c. One or more contactors are configured to control connection between the rechargeable batteries and the one or more o electrically powered tools. The distribution board is thereby configured to control which of the

O rechargeable batteries that are currently involved in providing electrical power to the one or 3 more powered tools, and which of the rechargeable batteries that are currently being

S 25 recharged. The distribution board may further comprise one or more fuses arranged to provide

E a fuse along one or more of the electrical connections established by the contactors.

LO

= The power system further comprises an energy management system (not shown) configured to

N control operation of the distribution board 340.

N

Specifically, the energy management system is configured to set the switch state of the one or more contactors 342a-c, thereby activating and deactivating electrical connections between the rechargeable batteries 322a, 322b and other electrical systems of the mining machine. The electrical connections activated by the contactors further determines if the batteries operate in an electrical parallel connection, in an electrical series connection, or operate alone when providing electrical power to an electrical system of the mining machine.

The power system can thereby make sure that the electrical power provided to the one or more powered tools is only supplied from batteries; there is no need to directly provide electrical power from an electrical power grid in the mine. Power peaks in electrical power grids due to high power operations can thereby be greatly reduced. According to some preferred aspects, the electrical power from the electrical power grid is solely used for charging the detached rechargeable batteries.

The mining machine 30 preferably comprises one or more inverters configured to receive direct current from one or more of the rechargeable batteries and transform the direct current to an alternating current suitable for a downstream electric motor. In the illustrated example, the mining machine 30 comprises one inverter for one or more electric motors 35 arranged to — provide mechanical power for driving the traction and the one or more powered tools of the mining machine, and one inverter for providing electrical power to an auxiliary electric motor 36 of the mining machine 30. In other words, the rechargeable batteries are configured to provide electrical power to a drive train 34 of the mining machine and/or an auxiliary electrical system of the mining machine. The one or more electric motors 35 may further provide power via a gear box and/or a clutch.

Each rechargeable battery 322a, 322b comprises a respective battery management system

N 324a, 324b. Each battery management system is arranged to retrieve operational data from the

N respective rechargeable battery. According to some aspects, the operational data comprises at = least one of state of charge, SOC, depth of discharge, DOD, state of health, and 7 25 internal temperature. The battery management systems are comprised in the energy

S management system and provide the energy management system with data which can be used

E as a basis for deciding how and when different electrical connections shall be activated via the

N distribution board. However, since the mining machine will typically operate as part of a daily

N cycle as part of an operational plan, it is desirable to take the operation plan into consideration when deciding which batteries shall be recharged and which batteries shall be providing power at any given moment.

Therefore, the machine control unit 38 is configured to store an operational plan for the high power operation. The machine control unit is further configured to obtain information relating to a respective electrical energy state of each rechargeable battery from the energy management system. The information relating to the respective electrical energy state preferable comprises the operational data retrieved by the energy management system. The machine control unit is also configured to transmit control signals to the energy management system via a control signal interface of the energy management system. The machine control — unit 38 thereby acts as a central processing hub for making decisions on how the batteries are used. The machine control unit collects information on the respective charge state of the batteries and uses the information of the charge states in combination with the operational plan in order to decide which electrical connections are activated and deactivated by the distribution board. In other words, the energy management system comprises a control signal interface configured to receive control signals from the machine control unit 38 of the mining machine 30. The energy management system is configured to control operation of the distribution board 340 based on control signals received from the machine control unit 38. The received control signals are based on an operational plan for the high power operation and information relating to a respective electrical energy state of each rechargeable battery 322a, 322b. The machine control unit 38 is preferably configured to obtain the information relating to a respective electrical energy state of each rechargeable battery and control operation of the distribution board based on the information relating to a respective electrical energy state of each

N rechargeable battery and the stored operational plan automatically.

N

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Claims

1. A power system (100; 200; 300) in a mining machine (10; 20a, 20b; 30) configured to perform an at least partly stationary, high power operation driving one or more electrically powered tools (12, 22; 32) of the mining machine, which power system is arranged to provide electrical power to the one or more electrically powered tools, the power system comprising an energy storage system (120), an energy management system (130; 230), and a distribution board (140; 240; 340), characterized in that the power system is configured to separate powering of the electrically powered tools from direct powering of the electrical power grid, that the energy storage system (120) comprises a plurality of exchangeable energy sources (122a-d, 222a-d, 322a-b) configured for recharging when detached from the mining machine, that the distribution board (140; 240; 340) comprises a plurality of contactors (142a-d, 342a-c), wherein one or more contactors are arranged to control a connection between the energy sources and the one or more electrically powered tools, and wherein the energy management system is configured to control operation of the distribution board.

2. The power system of claim 1, wherein an exchangeable energy source is one of a rechargeable battery, a supercapacitor, a rechargeable fuel cell and a flywheel.

3. The power system of claims 1 or 2, wherein one or more energy sources of the plurality of energy sources are detachably mounted on the mining machine. N O N g

2

4. The power system according to any of the preceding claims, wherein one or more I energy sources of the plurality of energy sources are mounted on a carrier separated from the [an a mining machine. LO LO > & 25 N

&

5. The power system according to any of claims 1-3, wherein the plurality of exchangeable energy sources are rechargeable batteries mounted on the mining machine,

wherein the plurality of rechargeable batteries are mounted with a spatial distribution selected to achieve at least one of a predetermined centre of gravity of the mining machine, ease of access to the plurality of exchangeable energy sources, providing a free field of rear vision for an operator of the mining machine and enable access to one or more auxiliary system of the mining machine.

6. The power system according to claim 5, wherein the plurality of exchangeable batteries are mounted on the mining machine, wherein the plurality of exchangeable batteries comprises at least a first and a second set of exchangeable batteries, and wherein the first and second set of exchangeable batteries are mounted at opposing sides of a centre line of the mining machine.

7. A mining machine (10; 2a, 20b; 30) comprising one or more electrically powered tools (12; 22; 32), a machine control unit (18; 28; 38), and a power system arranged to provide electrical power to the one or more electrically powered tools, characterized in that the power system is a power system according to any of claims 1-6.

8. The mining machine of claim 7, wherein the machine control unit is configured to store an operational plan for the high power operation, to obtain information relating to a respective electrical energy state of each energy source from the energy management system 2 and to transmit control signals to the energy management system via a control signal interface O N of the energy management system. O <Q o N =E

9. The mining machine according to claim 8, wherein the stored operational plan a w 25 comprises information relating to a power load demand having a temporal distribution. LO <t LO O N O N

10. The mining machine according to any of claims 7-8, wherein the control signals are configured to prevent each energy source engaged in providing electric power to the one or more electrically powered tools tofall below a predetermined electrical energy state threshold.

11. The mining machine according to any of claims 7-10, wherein the mining machine is a bolting rig or a drill rig. 0 AN O N Oo O O N T a a LO LO <t LO O a O N