Method and arrangement for controlling electric current in tether cable of mining vehicle

Patent metadata

Field	Value
Publication number	US-12344127-B2
Application number	US-202017612490-A
Country	US
Kind code	B2
Filing date	May 20, 2020
Priority date	May 22, 2019
Publication date	Jul 1, 2025
Grant date	Jul 1, 2025

Abstract

A method and arrangement are provided for controlling electric current in a tether cable of an electrically driven mining vehicle. An indicator of an equivalent cycle current that flows through said tether cable is determined, and one or more descriptors of an actual state of dynamically changing conditions of the tether cable are obtained. A current limiting value is determined on the basis of the indicator and the descriptors, and a total amount of current is limited that the mining vehicle draws through the tether cable to a value smaller than or equal to the determined current limiting value.

First claim

The invention claimed is:

1. A method for controlling electric current in a tether cable of an electrically driven mining vehicle, the method comprising:
determining an indicator of an equivalent cycle current that flows through said tether cable, wherein said indicator of an equivalent cycle current comprises an indicator of future equivalent cycle current that is expected to flow through said tether cable during a future duration of time, wherein the indicator of future equivalent cycle current is based, at least in part, on at least one of an indicator of a driving speed of the mining vehicle, an indicator of an estimated length of a working cycle of the mining vehicle, and an indicator of an estimated length of an idle cycle of the mining vehicle;
obtaining one or more descriptors of an actual state of dynamically changing conditions of the tether cable;
determining a current limiting value on the basis of said indicator of an equivalent cycle current and said descriptors; and
limiting a total amount of current that said mining vehicle draws through said tether cable to a value smaller than or equal to said determined current limiting value.

2. The method according to claim 1 , wherein said indicator of an equivalent cycle current includes an indicator of past equivalent cycle current that has flown through said tether cable during a recent duration of time.

3. The method according to claim 2 , wherein said indicator of the past equivalent cycle current is determined as a cumulative sum of momentary electric current values occurred in said tether cable divided by the length of said recent duration of time.

4. The method according to claim 1 , wherein said one or more descriptors of the actual state of dynamically changing conditions of the tether cable include one or more of an amount of said tether cable presently contained in a cable storage space of said mining vehicle, a temperature of a portion of said tether cable, and a temperature of said cable storage space.

5. The method according to claim 1 , further comprising responding to a momentary demand of electric power within the mining vehicle that is larger than allowed by the determined current limiting value, by temporarily boosting the amount of electric energy available on an onboard power link of the mining vehicle with electric energy drawn from a battery onboard the mining vehicle.

6. An arrangement for controlling electric current in a tether cable of an electrically driven mining vehicle, the arrangement comprising:
a processing unit configured to determine an indicator of an equivalent cycle current that flows through said tether cable, to obtain one or more descriptors of an actual state of dynamically changing conditions of the tether cable, and to determine a current limiting value on the basis of said indicator and said descriptors; and
a current limiter configured to limit a total amount of current that said mining vehicle draws through said tether cable to a value smaller than or equal to said determined current limiting value;
wherein said indicator of an equivalent cycle current comprises an indicator of future equivalent cycle current that is expected to flow through said tether cable during a future duration of time, wherein the indicator of future equivalent cycle current is based, at least in part, on at least one of an indicator of a driving speed of the mining vehicle, an indicator of an estimated length of a working cycle of the mining vehicle, and an indicator of an estimated length of an idle cycle of the mining vehicle.

7. The arrangement according to claim 6 , further comprising a voltage converter configured to convert a cable voltage of said tether cable into a power link voltage of an onboard power link of the mining vehicle, wherein said current limiter is configured to control said voltage converter to make said voltage converter select said power link voltage in dependence with said current limiting value.

8. The arrangement according to claim 6 , wherein said processing unit is configured to perform the method steps of:
determining an indicator of an equivalent cycle current that flows through said tether cable;
obtaining one or more descriptors of an actual state of dynamically changing conditions of the tether cable;
determining a current limiting value on the basis of said indicator and said descriptors; and
limiting a total amount of current that said mining vehicle draws through said tether cable to a value smaller than or equal to said determined current limiting value.

Assignees

• Sandvik Mining & Construction Oy

Inventors

• Verho Samuli
• Vatanen Harri
• Tiihonen Tommi
• Kouvo Mikko
• Juntunen Raimo
• Kitula Mikko

Classifications

• E02F9/00

  Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00 (laying-out or take-up devices for trailing electric cables B66C) · CPC title

• B60L2260/50

  by future state prediction · CPC title

• B60L2240/36

  Temperature of vehicle components or parts · CPC title

• B60L2240/12

  Speed · CPC title

• B60L2200/40

  Working vehicles · CPC title