JP2019205299A - Trolley type dump truck - Google Patents

Abstract

To provide a trolley type dump truck capable of adjusting regenerative electric power supplied to an overhead power line.SOLUTION: A trolley type dump truck (20) capable of traveling in a trolley mode of traveling by electric power supplied via a pantograph (5) from an overhead power line (15), comprises a resistor chopper (9) for adjusting electric energy supplied to a resistor (10) from a traveling motor (4), an overhead power line chopper (12) for adjusting the electric energy supplied to the pantograph from the traveling motor and controllers (6 and 11) for controlling operation of the resistor chopper and the overhead power line chopper, and the controllers control a supply quantity of supplying regenerative electric power generated in electric braking to an overhead power line by operating the overhead power line chopper and the resistor chopper based on an electric current measured value of the overhead power line inputted from an external part when the electric braking is applied to the traveling motor when traveling in the trolley mode.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a trolley type dump truck.

  For example, in mines, dump trucks that load ore etc. at the loading site, run on the uphill road in the loaded state, release the load at the dumping ground, and return to the loading site in the unloaded state. A series of operations are repeatedly performed. In this series of work, the fuel consumption is the largest and the load on the vehicle body is on the uphill road in the loaded state.

  Therefore, a trolley-type dump truck that is provided with a pantograph at the top of the vehicle body, contacts the pantograph with the overhead line built on the uphill road, and feeds the traveling motor from the overhead line via the pantograph to travel on the uphill road has been put into practical use. . This type of trolley-type dump truck includes a diesel engine, a generator driven by the diesel engine, and a travel motor that drives wheels, and includes a diesel mode and a trolley mode as travel modes. In the diesel mode, the generator is driven by the diesel engine, and the power generated by the generator is supplied to the traveling motor, so that the trolley type dump truck travels. In contrast, in the trolley mode, electric power is supplied from the overhead line to the traveling motor via the pantograph, so that the trolley type dump truck travels.

  Moreover, when decelerating the trolley type dump truck, the vehicle body can be electrically braked by making the traveling motor function as a generator (electric brake). When the electric brake is activated, regenerative power is generated by the travel motor. This regenerative power is consumed by converting it into thermal energy via a resistor, but if you use an electric brake during the trolley mode, the regenerative power flows into the resistor in addition to the power supplied from the overhead wire. In some cases, it may not be possible to consume enough power with the instrument alone. Then, the technique which returns the regenerative electric power produced | generated with the trolley type dump truck to an overhead wire is known (refer patent document 1).

US Pat. No. 8550007

  However, in the prior art described in Patent Document 1, the regenerative power supplied to the overhead line cannot be adjusted according to the state of the current flowing through the overhead line, and regenerative power exceeding the allowable current value of the overhead line is supplied. There is a risk of shorting the overhead wire.

  The technical subject of this invention is providing the trolley type dump truck which can adjust the regenerative electric power supplied to an overhead wire.

  In order to solve the above-described problem, an aspect of the present invention provides a vehicle body provided with a plurality of wheels, a travel motor that drives the plurality of wheels, and an upper portion of the vehicle body that contacts the overhead wire and travels A trolley mode in which a pantograph that supplies power to the motor and a resistor that consumes regenerative power generated during electric braking of the traveling motor as heat is used to travel with the power supplied from the overhead line via the pantograph In a trolley type dump truck capable of running on a resistor, a resistor chopper that is interposed between the running motor and the resistor and adjusts the amount of power supplied from the running motor to the resistor, and the running An overhead wire chopper interposed between the motor and the pantograph for adjusting the amount of electric power supplied from the travel motor to the pantograph; A controller that controls the operation of the chopper and the overhead wire chopper, and the controller is configured to input the external input when the traveling motor is electrically braked during traveling in the trolley mode. The supply amount of the regenerative power generated during the electric braking is controlled to be supplied to the overhead line by operating the overhead line chopper and the resistor chopper based on the actual measured current value of the overhead line. .

  According to the present invention, the regenerative power supplied to the overhead wire can be adjusted. Problems, configurations, and effects other than those described above will be clarified by the following description of embodiments.

The schematic block diagram of the mine where the overhead line was constructed. The side view of the trolley type dump truck concerning the embodiment of the present invention. The figure which shows the internal structure of the trolley type dump truck shown in FIG. The figure which shows the flow of the electric power at the time of the acceleration in the diesel mode, and the deceleration. The figure which shows the flow of the electric power at the time of the acceleration in trolley mode. The figure which shows the flow of the electric power at the time of the deceleration in trolley mode. The flowchart which shows the procedure of the control processing by a vehicle body controller.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, in each figure, the same code | symbol is described about the same element and the overlapping description is abbreviate | omitted.

(Composition of the entire mine)
FIG. 1 is a schematic configuration diagram of a mine in which overhead lines are installed. In the mine shown in FIG. 1, an overhead line 15 is installed along a climbing road between the loading place and the earthing place. Electric power necessary for climbing a trolley-type dump truck (hereinafter abbreviated as a dump truck) 20 is supplied to the overhead line 15 from the power station 30 through the substation 31. The dump truck 20 receives the electric power from the overhead line 15 through the pantograph 5 and converts it into the driving force of the traveling motor 4 to travel on the uphill road. Further, the overhead line 15 is provided with a plurality of current detectors 13 for detecting the current flowing through the overhead line 15, and the current measured values detected by the respective current detectors 13 are transmitted via the wireless communication line 32. It is transmitted to the truck computer 11 of the dump truck 20 (see FIG. 3).

(Appearance of dump truck)
FIG. 2 is a side view of the dump truck according to the embodiment of the present invention. As shown in FIG. 2, the dump truck 20 is directly connected to the vehicle body 22 provided with a pair of left and right front wheels 17F and a pair of left and right rear wheels 17R, a diesel engine (hereinafter abbreviated as engine) 1, and the engine 1. From the generator 2 driven by the engine 1, the control unit 3 for controlling the AC power generated by the generator 2, the pair of left and right traveling motors 4 directly connected to the pair of left and right rear wheels 17R, and the overhead wire 15 In order to receive electric power, it has the pantograph (current collector) 5 provided in the front upper part of the vehicle body 22 so that raising / lowering was possible, and the vessel (loading platform) 21 on which ore etc. are loaded.

  The cab 18 is provided with a mode selection switch 19 for switching the traveling mode to the diesel mode or the trolley mode. When the mode selection switch 19 is operated, a changeover switch 14 (see FIG. 3) described later is switched according to the selected travel mode. When the traveling mode is switched from the diesel mode to the trolley mode by the mode selection switch 19, the pantograph 5 is raised, and when the traveling mode is switched from the trolley mode to the diesel mode, the pantograph 5 is lowered.

  In the dump truck 20 configured in this manner, when traveling in the diesel mode traveling on a traveling path where the overhead line 15 is not installed, power is not supplied from the overhead line 15, so the engine 1 drives the generator 2, Generate electricity. The electric power generated by the generator 2 is once collected in the control unit 3. Electric power is supplied from the control unit 3 to each traveling motor 4 and converted into driving force for rotationally driving each rear wheel 17R by each traveling motor 4.

  On the other hand, when traveling in the trolley mode that travels along the overhead line 15, the dump truck 20 receives power from the overhead line 15 by raising the pantograph 5 and coming into contact with the overhead line 15. This overhead wire power is supplied from the control unit 3 of the dump truck 20 to each traveling motor 4, and each traveling motor 4 is driven.

(Internal configuration of dump truck)
FIG. 3 is a diagram showing the internal configuration of the dump truck. As shown in FIG. 3, the control unit 3 drives the engine 1 to convert the AC power generated from the generator 2 into DC power, and the rectifier 7 converts the DC power converted into DC power. An inverter 8 that supplies AC power to the motor 4, a resistor chopper 9 for consuming the regenerative power from the travel motor 4 by the resistor 10, and an overhead wire 15 through the pantograph 5 for the regenerative power from the travel motor 4. An overhead wire chopper 12 for supplying to the vehicle and a vehicle body controller 6. The choppers 9 and 12 are switching elements that operate at high speed.

  The vehicle body controller 6 controls the operation of the resistor chopper 9 and the overhead wire chopper 12 in addition to controlling the engine 1, the generator 2, and the inverter 8. The vehicle body controller 6 receives a switching signal (selection signal of the mode selection switch 19) and a brake signal (electric brake signal) from the selector switch 14, and the dump truck 20 travels in the trolley mode based on the signals. It is possible to identify whether or not the dump truck 20 is using the electric brake. The changeover switch 14 incorporates a current sensor (not shown), and a detection signal from the current sensor is input to the vehicle body controller 6.

  The overhead wire chopper 12 is electrically connected to the pantograph 5 via the changeover switch 14. When the traveling mode is switched to the trolley mode, electric power is supplied from the pantograph 5 to the overhead wire chopper 12 via the changeover switch 14. The vehicle body controller 6 controls the operation of the overhead wire chopper 12 and the inverter 8, whereby the electric power from the overhead wire 15 is supplied to the traveling motor 4.

  Further, the dump truck 20 transmits vehicle body information such as the operation status of the dump truck 20 to the outside of the vehicle body, and receives a current measurement value (current value information) of the overhead wire 15 from the outside of the vehicle body (current detector 13). A computer 11 is included. The vehicle body controller 6 transmits and receives various types of information to and from the track computer 11. When the traveling mode is switched to the trolley mode and the pantograph 5 comes into contact with the overhead line 15, the vehicle body controller 6 transmits the overhead line 15 from the track computer 11. The acquisition of the current measurement value of is started. The vehicle body controller 6 can determine whether or not the pantograph 5 is in contact with the overhead wire 15 based on a detection signal from a current sensor built in the changeover switch 14.

  The vehicle controller 6 and the track computer 11 constitute a “controller” of the present invention.

  Next, the flow of electric power in the dump truck 20 will be described with reference to FIGS. 4 is a diagram showing the flow of power in the dump truck 20 during acceleration and deceleration in the diesel mode, FIG. 5 is a diagram showing the flow of power in the dump truck 20 during acceleration in the trolley mode, and FIG. 6 is a diagram showing the trolley mode. It is a figure which shows the flow of the electric power in the dump truck 20 at the time of deceleration in.

(Power flow in diesel mode)
In the diesel mode in which the dump truck 20 travels in a place where there is no overhead line 15 such as a flat ground or a gentle slope, power is not received from the overhead line 15, so the pantograph 5 is lowered and is not in contact with the overhead line 15.

  As shown in FIG. 4, during the vehicle body acceleration in the diesel mode, the AC power generated from the generator 2 driven by the engine 1 is converted into DC power by the rectifier 7 inside the control unit 3. The converted DC power is supplied to the traveling motor 4 as AC power through the inverter 8. The inverter 8 can supply an arbitrary amount of AC power to the traveling motor 4 under the control of the vehicle body controller 6 (see arrow A in the figure).

  On the other hand, when the vehicle body decelerates, the traveling motor 4 functions as a generator and generates regenerative power from the braking force of the traveling motor 4. This regenerative power is converted from alternating current to direct current via the inverter 8. When the vehicle body controller 6 controls the operation of the resistor chopper 9, the regenerative power is supplied to the resistor 10, converted into heat by the resistor 10, and radiated to the outside of the vehicle body (see arrow B in the figure). At this time, since the rectifier 7 has a role of a diode, the regenerative power does not flow back to the generator 2.

(Power flow in trolley mode: during acceleration)
As shown in FIG. 5, at the time of vehicle acceleration in the trolley mode, the control unit 3 receives power from the overhead line 15 through the pantograph 5, and the control unit 3 supplies necessary power to the travel motor 4 through the inverter 8. In order to obtain the driving force of the car body. At this time, the engine 1 is in a standby idling state, and the generator 2 is stopped (see arrow C in the figure).

(Power flow in trolley mode: during deceleration)
As shown in FIG. 6, when the vehicle body decelerates in the trolley mode, the vehicle body controller 6 acquires the current measurement value of the overhead wire 15 from the track computer 11, and the operation of the resistor chopper 9 and the overhead wire chopper 12 based on the current measurement value. To control. Then, by switching the on / off operation of the resistor chopper 9 and the overhead wire chopper 12, the regenerative electric power generated during the electric braking of the traveling motor 4 is converted into the overhead wire 15 (see arrow D in the figure) or the resistor 10 ( (See arrow E in the figure).

  That is, in a situation where regenerative power is generated in the traveling motor 4, when the resistor chopper 9 is ON and the overhead wire chopper 12 is OFF, the regenerative power is consumed as exhaust heat by the resistor 10, and the resistance At the timing when the machine chopper 9 is OFF and the overhead wire chopper 12 is ON, regenerative power is supplied to the overhead wire 15 via the pantograph 5. And the supply amount of the regenerative electric power to the overhead wire 15 is controlled by adjusting the rate at which the resistor chopper 9 is ON and the rate at which the overhead wire chopper 12 is ON.

(Control of body controller)
Next, control of the operation of the resistor chopper 9 and the overhead wire chopper 12 will be described. FIG. 7 is a flowchart showing a procedure of control processing by the vehicle body controller 6.

  The vehicle body controller 6 determines whether or not the traveling mode is the trolley mode from the input switching signal of the selector switch 14 or the selection signal of the mode selection switch 19 (S1). ), The overhead wire chopper 12 is kept on (S2). Next, when the electric brake signal is input (S3 / YES), the vehicle body controller 6 turns off the resistor chopper 9 and controls the overhead wire chopper 12 to operate. Regenerative electric power generated at the time of electric braking is supplied to the overhead line 15 (S4).

  Next, the vehicle body controller 6 determines the magnitude of the current measurement value of the overhead line 15 and the current allowable value of the overhead line 15 (S5). In addition, when the current measurement value of the overhead line 15 is input from each of the plurality of current detectors 13, the vehicle body controller 6 determines the magnitude of the current allowable value using the maximum value among the plurality of current measurement values. . Here, the allowable current value of the overhead wire 15 is determined in advance based on the specifications of the overhead wire 15 and is stored in advance in a storage unit (not shown) of the vehicle body controller 6.

  When it is determined that the measured current value is equal to or greater than the allowable current value (S5 / YES), the vehicle body controller 6 turns off the overhead wire chopper 12 and operates the resistor chopper 9 to operate the regenerative power as a resistor. 10 (S6). Then, the vehicle body controller 6 executes the process of S6 until the measured current value is less than the allowable current value (S7 / NO → S6), and when the measured current value is less than the allowable current value (S7 / YES). Returns to S1. When the electric brake is not used (S3 / NO) and when the measured current value is less than the current allowable value in S5 (S5 / NO), the process returns to S1.

  On the other hand, when not in the trolley mode (S1 / NO), that is, in the diesel mode, the vehicle body controller 6 holds the overhead wire chopper 12 in the ON state (S8). Next, when an electric brake signal is input (S9 / YES), the vehicle body controller 6 turns off the overhead wire chopper 12 and controls the resistor chopper 9 to operate. The regenerative power generated during the electric braking is supplied to the resistor 10 (S4), and the process returns to S1. When the electric brake is not used (S9 / NO), the process returns to S1.

(effect)
As described above, according to the present embodiment, during the trolley mode, the resistor chopper 9 is turned off so as to supply (return) the regenerative power generated during the electric braking of the traveling motor 4 to the overhead wire 15 in principle. Since the operation of the overhead wire chopper 12 is controlled, energy can be effectively used. Moreover, when the measured current value of the overhead wire 15 exceeds the allowable current value of the overhead wire 15, the overhead wire chopper 12 is turned off to control the operation of the resistor chopper 9 so that the regenerative power is consumed by the resistor 10. Therefore, there is no possibility that regenerative power exceeding the allowable current value of the overhead wire 15 is supplied and the overhead wire 15 is short-circuited. That is, in this embodiment, by controlling the operation of the overhead wire chopper 12 and the resistor chopper 9 based on the actual measured current value of the overhead wire 15, the supply amount (current) of regenerative power flowing through the overhead wire 15 during electric braking is reduced. Since it can be adjusted, the regenerative power can be effectively used without causing the overhead wire 15 to be short-circuited.

  Further, during the diesel mode, the operation of the resistor chopper 9 is controlled by turning off the overhead wire chopper 12 at the time of electric braking, so that the regenerative power can be reliably consumed by the resistor 10.

  Moreover, since the vehicle body controller 6 selects and controls these maximum values when a plurality of actual current measurement values are input, the possibility of short-circuiting the overhead wire 15 can be further reduced. Further, since the vehicle body controller 6 starts to acquire the actual measured current value of the overhead line 15 when the pantograph 5 contacts the overhead line 15, the communication time between the track computer 11 and the vehicle body controller 6 can be reduced, and the control process The burden of is reduced.

  Of course, in the mine where the overhead line 15 is erected, the power is supplied from the overhead line 15 to the dump truck 20, so that the cycle time is reduced by increasing the traveling speed of the dump truck 20 on the uphill road, and the productivity is improved. Needless to say, fuel efficiency can be improved.

  The present invention is not limited to the embodiment described above. For example, the above-described embodiment has been described in detail for easy understanding of the present invention, and is not necessarily limited to one having all the configurations described.

  For example, the actual measured current value may be transmitted to the dump truck 20 via a wired communication line instead of the wireless communication line 32. Further, a monitor or the like that displays to the operator whether the regenerative power is supplied to the overhead wire 15 or the resistor 10 may be installed in the cab 18. The changeover switch 14 may be built in the pantograph 5. Further, instead of the diesel engine 1, an engine using gasoline as fuel may be used.

  Further, the current value information of the overhead line 15 may be transmitted from the substation 31 to the track computer 11 instead of the actual measured current value detected by the current detector 13. In this case, there is an advantage that the installation cost of the current detector 13 can be reduced.

DESCRIPTION OF SYMBOLS 1 Diesel engine 2 Generator 4 Traveling motor 5 Pantograph 6 Car body controller (controller)
9 Resistor chopper 10 Resistor 11 Track computer (controller)
12 Overhead Chopper 13 Current Detector 14 Changeover Switch 15 Overhead Wire 17F Front Wheel (Wheel)
17R Rear wheel (wheel)
19 Mode selection switch 22 Body

Claims (5)

A vehicle body provided with a plurality of wheels;
A travel motor for driving the plurality of wheels;
A pantograph that is disposed at the top of the vehicle body and that supplies power to the travel motor in contact with an overhead line;
A resistor that consumes regenerative power generated during electric braking of the travel motor as heat, and is capable of traveling in a trolley mode that travels with power supplied from the overhead line via the pantograph In the track
A resistor chopper that is interposed between the travel motor and the resistor and adjusts the amount of power supplied from the travel motor to the resistor;
An overhead wire chopper that is interposed between the travel motor and the pantograph and adjusts the amount of power supplied from the travel motor to the pantograph;
A controller for controlling the operation of the resistor chopper and the overhead wire chopper,
When the electric motor is applied to the traveling motor during traveling in the trolley mode, the controller is configured to use the overhead wire chopper and the resistor chopper based on an actual measured value of the overhead wire input from the outside. To control the supply amount of the regenerative power generated during the electric braking supplied to the overhead wire. In the trolley type dump truck according to claim 1,
The controller is a case where electric braking is applied to the traveling motor during traveling in the trolley mode, and an actual measured current value of the overhead wire inputted from outside is less than a predetermined allowable current value of the overhead wire. In this case, the operation of the resistor chopper is stopped and the overhead wire chopper is operated to supply the regenerative power generated during traveling in the trolley mode to the overhead wire via the pantograph. ,
When the measured current value of the overhead wire is equal to or greater than the allowable current value of the overhead wire, the operation of the overhead wire chopper is stopped and the resistor chopper is operated, and is generated during the electric braking in the trolley mode. The trolley type dump truck is controlled so as to supply the regenerative power to the resistor. In the trolley type dump truck according to claim 2,
A diesel engine,
A generator driven by the diesel engine,
It is possible to travel by switching between the diesel mode that travels by driving the travel motor with the electric power generated by the generator, and the trolley mode,
The controller stops the operation of the overhead wire chopper and controls the operation of the resistor chopper when electric braking is applied to the traveling motor during traveling in the diesel mode. A trolley-type dump truck, characterized in that the regenerative power generated during the electric braking is supplied to the resistor. In the trolley type dump truck according to claim 1,
When the current measured values are respectively input from the plurality of current detectors provided on the overhead line to the controller, the controller determines the overhead line based on the maximum value among the plurality of input current measured values. A trolley type dump truck that controls operations of the chopper for a resistor and the chopper for the resistor. In the trolley type dump truck according to claim 1,
The trolley-type dump truck, wherein the controller starts acquiring the measured current value when the pantograph contacts the overhead line.

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