FI130709B1

FI130709B1 - Mining machine

Info

Publication number: FI130709B1
Application number: FI20235265A
Authority: FI
Inventors: Emil Andersson
Original assignee: Epiroc Rock Drills Ab
Priority date: 2017-11-06
Filing date: 2018-10-25
Publication date: 2024-02-02
Also published as: AU2018359330B2; AU2018359330A1; FI20235265A1; FI20205452A; WO2019088899A1; SE1751370A1; FI130169B; SE541333C2; ZA202000940B; FI20205452A1; CA3073012A1

Abstract

The present disclosure relates to a mining machine (30) comprising one or more electrically powered tools (32), a machine control unit (38), and a power system (300) configured to provide electrical power to the one or more electrically powered tools (32) and a drive train (34) of the mining machine, which power system (300) comprises a grid connection (310), an energy storage system, an energy management system, a distribution board (340), and an inverter configured to transform a received direct current to an alternating current for a downstream electric motor (35), wherein the electric motor (35) is arranged to drive the one or more electrically powered tools (32) and a drive train (34) of the mining machine, wherein the energy storage system (120) comprises a plurality of rechargeable energy sources (322a-b), wherein the plurality of rechargeable energy sources (322a-b) comprise a first set of rechargeable energy sources (322a) and a second set of rechargeable energy sources (322b) that are mutually exclusive subsets of the plurality of rechargeable energy sources (322a-b) and configured for parallel respective connections to the electrically powered tools (32) and the drive train (34), wherein the energy management system is configured to control operation of the distribution board (340) to provide connection to the inverter such that the first and second rechargeable energy sources (322a, 322b) are connected in parallel electrical connection to provide electrical power to the electric motor (35).

Description

Mining Machine

TECHNICAL FIELD

The present disclosure relates to a mining machine comprising a power system.

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 —forventilation 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 increasing use of electrical power in mining operations brings with it several challenges.

One problem facing mining operations is that the nearest electric power grid, e.g. at a nearby city or at the mining site, is not dimensioned to meet the full needs of the mining operations in question. An additional challenge occurs when one or more mining machines perform

N 20 stationary, high power operations driving one or more power tools of the respective mining

N machine, such as drilling, which results in high peak loads on the electrical power grid in the ? mine. Since the mining machines operate in planned cycles, the high power operations result in = an irregular load on the electrical power grid, with intermittent high peak loads. There is thus a & need in the art for systems which reduces the intermittent high peak loads on the electrical

S 25 power grid while also enabling electrically powered mobility of the mining machines.

N SUMMARY

N

One of the main problems faced when mining is the intermittent high peak power demands placed on the electrical power grid. The present disclosure significantly reduces the need for high power from the electrical power grid by using rechargeable energy sources to power the high power operations. The rechargeable energy sources will preferably be completely separated from the electrical power grid when providing electrical power to the mining machine. However, even if the rechargeable energy sources are being recharged while simultaneously providing power to a high power operation, the rechargeable energy sources will act as buffers and reduce the electrical power demand of the electrical power grid.

The present disclosure relates to a mining machine as defined in claim 1.

According to a first aspect of the disclosure, the mining machine comprises one or more electrically powered tools, a machine control unit, and a power system configured to provide electrical power to the one or more electrically powered tools and to a drive train of the mining machine. The power system comprises a grid connection, an energy storage system, an energy management system, and a distribution board, and an inverter configured to transform a received direct current to an alternating current for a downstream electric motor, wherein the electric motor is arranged to drive the one or more electrically powered tools and the drive train of the mining machine. The energy storage system comprises a plurality of rechargeable energy sources, wherein the plurality of rechargeable energy sources comprise a first set of rechargeable energy sources and a second set of rechargeable energy sources that are mutually exclusive subsets of the plurality of rechargeable energy sources and are configured for parallel respective connections to the electrically powered tools and the drive train. The energy management system is configured to control operation of the distribution board to provide connection to the inverter such that the first and second rechargeable energy sources are + connected in a parallel electrical connection to provide electrical power to the electric motor.

N

& o + In some examples, a power system in the mining machine is configured to perform an at least

I partly stationary, high power operation driving one or more electrically powered tools of the = 25 — mining machine. One or more first contactors are configured to control a first connection

E between the plurality of rechargeable energy sources and the one or more electrically powered

S tools. One or more second contactors are configured to control a second connection between

N the plurality of rechargeable energy sources and the grid connection to enable recharging of the

N plurality of rechargeable energy sources. The energy management system is configured to control operation of the distribution board.

The power system provides a buffer between the electrical power grid and the electrically powered tools. In particular, the power system enables recharging of energy sources not currently involved in the high power operation or recharging during concurrent 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 direct connection to the electrical power grid. A further effect is that a plurality of, possibly different, mining machines configured to perform an at least partly stationary, high power operation driving one or more electrically powered tools of the respective mining machine, can be supported by the electrical power grid.

If each mining machine were to use the electrical power grid to power a respective high power operation simultaneously, the electrical power grid may not be able to provide the necessary electrical power; the disclosed power system enables a reduction of the electrical power demand to recharging a plurality of batteries, which requires 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 connected to the power grid via the grid connection in order to berecharged.

According to some aspects, a rechargeable energy source is one of a rechargeable battery, a supercapacitor, a rechargeable fuel cell and a flywheel. These rechargeable energy sources

N enable sufficient energy storage with respect to weight and operational demands, while also s being able to provide the necessary power output during discharge. <Q

E 25 According to some aspects, the energy management system is configured to control operation

E of the distribution board during performance of the high power operation to activate the first 2 connection between a first set of rechargeable energy sources out of the plurality of 0 rechargeable energy sources and the one or more electrically powered tools and to activate the

S second connection between a second set of rechargeable energy sources out of the plurality of rechargeable energy sources and the grid connection to recharge one or more rechargeable energy sources of the second set of rechargeable energy sources. According to some further aspects, the first and second sets of rechargeable energy sources are mutually exclusive subsets from the plurality of rechargeable energy sources. The energy management system thereby controls the first set of rechargeable energy sources to drive the one or more electrically powered tools while the second set of rechargeable energy sources are being recharged via the — grid connection. When the first and second sets of rechargeable energy sources are mutually exclusive subsets, the load demand of the high power operation does not directly affect the electrical power grid since the high power operation is powered by the first set of rechargeable energy sources. Only the second set of rechargeable energy sources places a load demand on the electrical power grid as they are being recharged, a load that is significantly more balanced and lower than the electrical power load demand associated with the high power operation.

The electrical power load demand associated with the high power operation on the electrical power grid is thereby reduced.

According to some aspects, the plurality of rechargeable energy sources is a plurality of rechargeable batteries, wherein the energy management system comprises an energy source management system configured to retrieve operational data for each rechargeable battery of the plurality of rechargeable batteries, and wherein the distribution board is configured to activate the first and second connections based on information from the energy management system. According to some further aspects, the operational data comprises at least one of state of charge, SOC, depth of discharge, DOD, state of health, SOH, and internal temperature. By collecting operational data, decisions on which batteries to use to power the powered tools and which to be recharged can be made automatically during operational use. In addition to charge levels of the batteries, the operational data may also be used to prevent overheating as well as

N collecting statistics for determining the condition of the respective batteries.

N

5 According to some aspects, one or more of the plurality of rechargeable batteries is configured

E 25 to provide electrical power to a power train of the mining machine and/or an auxiliary electrical

E system of the mining machine. The plurality of rechargeable batteries thereby extends, in 2 addition to providing power for the at least partly stationary, high power operation, the 3 functionality of the power system, thereby eliminating the need for separate power sources for

S the power train and/or the auxiliary electrical system.

According to some aspects, the energy management system comprises a control signal interface configured to receive control signals from a machine control unit of the mining machine, and wherein the energy management system is configured to control operation of the distribution board based on control signals received from the machine control unit. According to some 5 further aspects, 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. The operation of the power system can thereby be controlled 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 rechargeable 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 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 and to transmit control signals to the energy management system via a control signal interface of the energy management system. According to some 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 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 guestion than the power system alone, and is

N therefore in a better position to make informed decisions on the best use of the rechargeable s batteries. In particular, the availability of the operational plan enables improved electrical

I 25 energy resource management, since the temporal distribution of the demand for electrical = power can be taken into account. a 2 According to some aspects, the control signals are configured to prevent each energy source 3 engaged in providing electric power to the one or more electrically powered tools to fall below

S 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 of the 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 as 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.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 illustrates a mining machine and a power system in a mining machine according to the present disclosure; — Figure 2 illustrates a mining machine and a power system in a mining machine according to the present disclosure; and

Figure 3 illustrates a mining machine and a power system in a mining machine according to the present disclosure.

DETAILED DESCRIPTION

— Figure 1illustrates mining machine 10 and a power system 100 in a mining machine 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 configured to provide electrical power to the one or more electrically powered tools 12. The mining machine 10 is configured to perform an at least partly <t

S 20 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

O

K machines may experience the need to perform an at least partly stationary, high power

E operation, and thus benefit from the disclosed power system. Bolting rigs, e.g., rock bolting rigs a

LO and cable bolting rigs, and drill rigs, e.g. face drill rigs and production drill rigs, mainly perform ©

D 25 stationary high power operations and are thus particularly suitable for having a power system

O 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 configured to provide electrical power to the one or more electrically powered tools 12. The power system 100 comprises a grid connection 110. The grid connection 110 enables an electrical power grid to provide power to the power system 100, and hence the mining machine 10. The power system 100 also comprises an energy storage system 120. The power system 100 additionally comprises an energy management system 130. The energy management system 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 rechargeable energy sources 122a, 122b, 122c, 122d. According to some aspects, a rechargeable energy source 122a, 122b, 122c, 122d is one of arechargeable battery, a supercapacitor, a rechargeable fuel cell and a flywheel.

The power system 100 yet further comprises a distribution board 140. The purpose of the distribution board 140 is to provide electrical connections between the rechargeable energy sources 122a, 122b, 122c, 122d and electrical systems and interfaces with which the rechargeable energy sources are intended to interact. The distribution board 140 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 range or up to 1500 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, as well as the grid connection. Specifically, one or more first 142a, 142b contactors are configured to control a first connection 144 + between the plurality of rechargeable energy sources 122a, 122b, 122c, 122d and the one or

S more electrically powered tools 12. One or more second contactors 142c, 142d are configured 5 to control a second connection 146 between the plurality of rechargeable energy sources 122a,

E 25 122b, 122c, 122d and the grid connection 110 to enable recharging of the plurality of

E rechargeable energy sources 122a, 122b, 122c, 122d. The power system may thereby be 2 configured to provide a buffer between the electrical power grid and the electrically powered 3 tools. In particular, the power system enables recharging of energy sources not currently

S involved in the high power operation, as will be described further below.

With the above disclosed configuration of power system, 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 direct connection to the electrical power grid. A further effect is that a plurality of, possibly different, mining machines configured to perform an at least partly stationary, high power operation driving one or more electrically powered tools of the respective mining machine, can be supported by the electrical power grid. If each mining machine were to use the electrical power grid to power a respective high power operation simultaneously, the electrical power grid may not be able to provide the necessary electrical power; the disclosed power system enables a reduction of the electrical power demand to recharging a plurality of batteries, which only requires a lower and more stable electrical power source. The power system further enables continuous or uninterrupted operation since the distribution board enables immediate or overlapping reallocation of available energy sources; when some rechargeable energy sources reach a critical charge level or are depleted, they may be replaced by more fully charged rechargeable energy sources by a switch of one or more of the contactors. The replaced rechargeable energy sources, e.g., the energy sources having reached a critical charge level or being depleted, may at the same time be connected to the power grid via the grid connection in order to be recharged.

The energy management system 130 is further configured to control operation of the distribution board 140. The energy management system thereby extends the functionality of the power system 100 by enabling the power system to be operated using automatic control via the energy management system 130.

N

< According to some aspects, the energy management system 130 is configured to control 5 operation of the distribution board 140 during performance of the high power operation to

E 25 activate the first connection 144 between a first set of rechargeable energy sources 122a, 122b

E out of the plurality of rechargeable energy sources 122a, 122b, 122c, 122d and the one or more 2 electrically powered tools 12 and to activate the second connection 146 between a second set 3 of rechargeable energy sources 122c, 122d out of the plurality of rechargeable energy sources < 122a, 122b, 122c, 122d and the grid connection 110 to recharge one or more rechargeable energy sources of the second set of rechargeable energy sources 122c, 122d. According to some further aspects, the first and second sets of rechargeable energy sources are mutually exclusive subsets from the plurality of rechargeable energy sources. The energy management system 130 thereby controls the first set of rechargeable energy sources 122a, 122b to drive the one or more electrically powered tools 12 while the second set of rechargeable energy sources 122c, 122d are being recharged via the grid connection. Only the rechargeable energy sources providing electrical power to the one or more electrically powered tools and being recharged at the same time provide a link between the electrical power grid and the one or more powered tools, thereby acting as buffers and reducing the electrical power load on the electrical power grid. In case the first and second sets of rechargeable energy sources are mutually exclusive subsets, the load demand of the high power operation does not affect the electrical power grid, but only the first set of rechargeable energy sources; only the second set of rechargeable energy sources places a load demand on the electrical power grid as they are being recharged, which is significantly lower than the electrical power load demand associated with the high power operation. The electrical power load demand associated with the high power operation on the electrical power grid is thereby eliminated. — According to some aspects, the plurality of rechargeable energy sources 122a, 122b, 122c, 122d is a plurality of rechargeable batteries. According to some aspects, the plurality of rechargeable batteries is Lithium ion batteries. The rechargeable batteries may be separate units, each comprising one or more battery cells, or a single unit comprising a plurality of battery cells, wherein one or more battery cells of the plurality of battery cells define a rechargeable battery.

The energy management system 130 further comprises an energy source management system 132 configured to retrieve operational data for each rechargeable battery of the plurality of rechargeable batteries 122a, 122b, 122¢, 122d. According to some aspects, the energy source

N management system comprises one or more battery management systems, BMS. According to s some further aspects, each rechargeable battery comprises a respective BMS. <Q

E 25 The distribution board 140 is also configured to activate the first and second connections 144,

E 146 based on information from the energy management system 130. Operational data may 2 thereby be passed on from the energy management system, possibly via the machine control 0 unit, to the distribution board in order to activate the first and second connections based on

S the operational data. According to some further aspects, the operational data comprises at least one of state of charge, SOC, depth of discharge, DOD, state of health, and internal temperature.

The operational data thereby enables controlling the first and second connections based on how much electrical energy is still available in each rechargeable battery, as well as the working status of each rechargeable battery. For long duration, high power operations, where operational data indicates that a single rechargeable battery will not be able to provide sufficient energy, the first and second connections may be configured such that two or more of the rechargeable energy sources are connected in a parallel electrical connection to provide electrical power to the powered tools 12.

Rechargeable batteries may gradually loose health, i.e., recharging capacity, as they are recharged over many recharge cycles. The lifetime of the rechargeable batteries can be extended by not fully depleting prior to recharge. With knowledge of the SOC and/or the DOD, the operational data can provide information on the remaining electrical energy of each rechargeable battery. The first and second connections can thereby be configured and activated to ensure that the SOC and/or DOD is kept above a predetermined level for each rechargeable battery. In other words, 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 operational data may also be used to collect statistical information which can be used to determine a state of health of each rechargeable battery, e.g. by the machine control unit 18. If the health of a rechargeable battery is insufficient to provide the necessary electrical power and/or operate for a desired duration, the operational data relating to the health of the rechargeable battery can be used to either assist the rechargeable battery with another rechargeable battery, e.g. via an electrical parallel connection, or the rechargeable battery + having poor health may be replaced with another rechargeable battery for the duration of the

S high power operation.

I According to some aspects, one or more of the plurality of rechargeable batteries 122a, 122b, = 25 122c,122dis configured to provide electrical power to a power train 14 of the mining machine

E and/or an auxiliary electrical system 16 of the mining machine. The power system thereby

S provides the mining machine with electrical power for other systems in addition to the powered

N tools 12, which enables the mining machine to be fully operated using electrical energy.

N

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 18 is configured to store an operational plan for the high power operation. The machine control unit 18 is further configured to obtain information relating to a respective electrical energy state of each energy source 122a, 122b, 122c, 122d from the energy management system 130 and to transmit control signals to the energy management system 130 via a control signal interface 134 of the energy management system 130. In other words, according to some aspects, the control signals received by the energy management system of 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. According to some further aspects, the stored operational plan comprises information relating to a power load demand having a temporal distribution. — Figure 2 illustrates a mining machine 20 and a power system 200 in a mining machine according to the present disclosure. The mining machine 20 comprises one or more electrically powered + tools 22, a machine control unit 28, and a power system configured to provide electrical power

S tothe one or more electrically powered tools. The power system 200 is configured to perform 5 an at least partly stationary, high power operation driving the one or more electrically powered

E 25 tools 22 of the mining machine 20. The power system 200 is configured to provide electrical

E power to the one or more electrically powered tools 22. The power system 200 comprises a grid 2 connection 210. The power system further comprises an energy storage system. The power 3 system 200 also comprises an energy management system 230. The power system 200

S additionally comprises a distribution board 240. The energy storage system comprises a plurality of rechargeable energy sources 222a, 222b, 222c, 222d. The energy storage system is here illustrated with one or more pairs of rechargeable batteries. The rechargeable batteries may be separate units, each comprising one or more battery cells, or a single unit comprising a plurality of battery cells, wherein one or more battery cells of the plurality of battery cells define a rechargeable battery. Rechargeable batteries organised as separate units, each comprising one or more battery cells facilitates distribution of the rechargeable batteries across the mining machine. Each pair of rechargeable batteries is distributed opposite each other about a centreline along a longitudinal direction of the mining machine 20. The plurality of rechargeable batteries thereby has a weight distribution that assists in increasing the stability of the mining machine during the at least partly stationary, high power operation. Added weight due to a plurality of batteries may also be advantageously used to increase stability of the mining — machine.

The distribution board 240 comprises a plurality of contactors. 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, e.g. in the four hundred to six hundred Volt range. One or more first contactors are configured to control a first connection between the plurality of rechargeable batteries and the one or more electrically powered tools. One or more second contactors are configured to control a second connection between the plurality of rechargeable energy sources and the grid connection to enable recharging of the plurality of rechargeable energy sources.

The energy management system 230 is configured to control operation of the distribution board — 240. Specifically, the energy management system 230 is configured to control operation of the distribution board 240 during performance of the high power operation to activate the first + connection between a first set of rechargeable batteries 222a, 222b out of the plurality of

S rechargeable batteries 222a, 222b, 222c, 222d and the one or more electrically powered tools 5 22 and to activate the second connection between a second set of rechargeable energy sources

E 25 122c, 122d out of the plurality of rechargeable energy sources 222a, 222b, 222c, 122d and the

E grid connection 210 to recharge one or more rechargeable energy sources of the second set of 2 rechargeable energy sources 222c, 222d. The first and second sets of rechargeable batteries are 3 mutually exclusive subsets from the plurality of rechargeable energy sources. In the example of

S only two rechargeable batteries, one of the rechargeable batteries provides electrical power to the one or more powered tools while the other rechargeable battery is set to be recharged via the grid inlet. Additionally, the rechargeable battery which is not used for providing electrical power to the one or more powered tools may be used to provide electrical power to auxiliary systems part of the mining machine and/or external devices, such as light towers, pumps, supporting grid or other machines, e.g. other mining machines.

The machine control unit 28 is configured to store an operational plan for the high power operation. The stored operational plan enables efficient use of the rechargeable batteries. For instance, as there will be an abruption in the switch over between the different rechargeable batteries, it is desirable to coordinate switching with ongoing operations of the mining machine.

The stored operational plan facilitates efficient switch coordination. The stored operational plan comprises information relating to a power load demand having a temporal distribution. In other — words, the stored operational plan comprises information what the power load demand will be during the current operational cycle in which the mining machine is involved. The stored operational plan thus enables a comparison with the power load demand during an operational cycle and the energy resources provided by the rechargeable batteries, thereby enabling optimization of the power usage with respect to e.g. peak power, energy duration and/or — battery health. The machine control unit is further configured to obtain information relating to a respective electrical energy state of each rechargeable battery 222a, 222b, 222c, 222d from the energy management system 230.

The machine control unit 28 is further configured to transmit control signals to the energy management system 230 via a control signal interface of the energy management system. The 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. Thus, the energy + management system comprises a control signal interface configured to receive control signals

S from a machine control unit of the mining machine. The energy management system 230 is 5 further configured to control operation of the distribution board 240 based on the control

E 25 signals received from the machine control unit 28. The machine control unit 28 is preferably

E configured to analyse the power load demand of the operational plan and the information 2 relating the respective electrical energy states of the rechargeable batteries to generate the 0 control signals automatically. According to some aspects, the machine control unit 28 is

S configured to learn, e.g. using a machine learning algorithm, how to optimally perform the switching operations of the contactors in order to maximize a performance metric, e.g. minimizing electrical energy usage or maximizing battery lifetime.

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 chargers, 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 requires 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 a grid connection 310, an energy storage system, and a distribution board 340. The energy storage system comprises a plurality of rechargeable batteries, here illustrated as a pair of rechargeable batteries 322a, 322b mounted at opposing sides of a centre line of the mining machine 30. In order to effectively receive the electrical power from the grid connection 310 and use it to charge the rechargeable batteries, the power system 300 comprises a charger 312 arranged to receive electrical power from the

N grid connection 310 and charge the rechargeable batteries using the received electrical power. s The charger 312 is connected to the distribution board 340. <Q

E 25 The distribution board 340 comprises a plurality of contactors 342a-d and is configured to

E control which of the rechargeable batteries that are currently involved in providing electrical 2 power to the one or more powered tools, and which of the rechargeable batteries that are 0 currently being recharged. One or more first contactors are configured to control a first

S connection the rechargeable batteries and the one or more electrically powered tools. One or more second contactors are configured to control a second connection between the rechargeable batteries and the grid connection to enable recharging of the rechargeable batteries. According to an aspect of the disclosure, the power system 300 is configured to adjust a voltage level of the first and/or second connection prior to activation of the respective contactors in order to avoid a power surge during the switch. This may be implemented by connecting a resistor and an auxiliary contactor in parallel with a main contactor, e.g., a first or second contactor. The distribution board may further comprise one or more fuses arranged to provide a fuse along one or more of the electrical connections established by the contactors.

The power system further comprises an energy management system (not shown) configured to control operation of the distribution board 340.

Specifically, the energy management system is configured to set the switch state of the one or more contactors 342a-d, 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 a rechargeable — battery not currently providing electrical power to a high power operation. < The mining machine 30 preferably comprises one or more inverters configured to receive direct

S 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

E 25 provide mechanical power for driving the traction and the one or more powered tools of the 10 mining machine, and one inverter for providing electrical power to an auxiliary electric motor

D 36 of the mining machine 30. In other words, the rechargeable batteries are configured to

O provide electrical power to a drive train 34 of the mining machine and may also provide electrical power to 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 324a, 324b. Each battery management system is arranged to retrieve operational data from the 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 internal temperature. The battery management systems are comprised in the energy management system and provide the energy management system with data which can be used as a basis for deciding how and when different electrical connections shall be activated via the distribution board. However, since the mining machine will typically operate as part of a daily 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

N board. In other words, the energy management system comprises a control signal interface s configured to receive control signals from the machine control unit 38 of the mining machine

I 25 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

N 30 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 rechargeable battery and the stored operational plan automatically. i

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Claims

1. A mining machine (30) comprising one or more electrically powered tools (32), a machine control unit (38), and a power system (300) configured to provide electrical power to the one or more electrically powered tools (32) and a drive train (34) of the mining machine, which power system (300) comprises a grid connection (310), an energy storage system, an energy management system, a distribution board (340), and an inverter configured to transform a received direct current to an alternating current for a downstream electric motor (35), wherein the electric motor (35) is arranged to drive the one or more electrically powered tools (32) and the drive train (34) of the mining machine, wherein the energy storage system (120) comprises a plurality of rechargeable energy sources (322a-b), characterized in that the plurality of rechargeable energy sources (322a-b) comprise a first set of rechargeable energy sources (322a) and a second set of rechargeable energy sources (322b) that are mutually exclusive subsets of the plurality of rechargeable energy sources (322a-b), wherein the energy management system is configured to control operation of the distribution board (340) to — provide parallel respective connections between the plurality of rechargeable energy sources (322a-b) and the inverter such that the first set of rechargeable energy sources (322a) and the second set of rechargeable energy sources (322b) are connected in parallel to provide electrical power to the electric motor (35).

2. The mining machine (30) of claim 1, wherein the plurality of rechargeable energy sources (322a-b) is a pair of rechargeable batteries (322a; 322b) mounted at opposing sides of a centre line of the mining machine (30). 3

N 3. The mining machine (30) of claim 2, wherein the power system comprises a ? 25 charger (312) connected to the distribution board (340).

E 4. The mining machine (30) of claim 3, wherein the distribution board (340) 2 comprises a plurality of contactors (342a-d), wherein one or more first contactors (342c) are 3 configured to control a first connection between the rechargeable batteries (322a; 322b) and N 30 the inverter and one or more second contactors (342a,b,d) are configured to control a second connection between the rechargeable batteries and the charger (312) to enable recharging of the rechargeable batteries.

5. The mining machine (30) of claim 4, wherein the energy management system is configured to activate the one or more second contactors (342a,b,d) of the distribution board (340) based on operational data comprising at least one of state of charge, SOC, depth of discharge, DOD, state of health, and internal temperature of rechargeable batteries (3223; 322b).

6. The mining machine (30) according to any of the preceding claims, wherein the mining machine is a bolting rig or a drill rig. i N O N > N I a a LO © N LO O N O N