JP6592470B2 - Electric drive dump truck - Google Patents

Description

  The present invention relates to an electrically driven dump truck that travels by driving a traveling motor with electric power generated by a generator.

  In recent years, various types of work machines have been used at the mine site, and for example, dump trucks are sometimes used for conveying mined ore. Ore transport costs in mines are classified into labor costs, fuel costs, maintenance costs, initial investment, etc. Of these, fuel costs are said to be the second largest after labor costs, improving the profits of the mining business. For this purpose, energy saving of dump trucks is required. Therefore, various techniques have been proposed in the past in order to improve the fuel efficiency of the mining dump truck.

  As one of the conventional techniques of this type, an electric work vehicle that travels by driving a traveling motor with electric power generated by a generator directly connected to an engine has been proposed (for example, see Patent Document 1 below). Specifically, this electric work vehicle includes an electric motor for driving and driving, the electric motor by converting DC power from a generator into AC power having a variable frequency, and AC from the electric motor. A bidirectional converter that converts power output into direct current power; a resistor connected to the bidirectional converter to consume electromotive force regenerated by the electric motor; and a blower that supplies cooling air to the resistor. It has.

US Pat. No. 4,307,300

  When the vehicle decelerates, the prior art disclosed in Patent Document 1 described above converts the kinetic energy of the vehicle into electrical energy (regenerative power) using a travel motor as a retarder, and this electrical energy is converted into a resistor ( The heat generated by the resistor is released into the air by supplying it to the grid resistor and converting it into thermal energy. At this time, it is necessary to supply the cooling air to the resistor by rotating the blower so that the surrounding equipment is not damaged by the heat of the resistor. Therefore, a blower motor is provided in parallel with the resistor and the electric energy from the retarder is used. The blower is operating. However, in this configuration, since the current flowing through the blower is determined by a resistor connected in parallel, there is a problem that the amount of cooling air cannot be freely adjusted for the resistor when the vehicle decelerates.

  The present invention has been made in view of such a state of the art, and an object thereof is to provide an electrically driven dump truck that can freely set a cooling performance for a resistor when the vehicle is decelerated.

  In order to achieve the above object, a typical present invention includes an engine provided in a vehicle, two traveling motors that drive the wheels of the vehicle separately to drive left and right, and an output shaft of the engine. A main generator and an auxiliary generator that generate electric power with the driving force of the engine, a generated power regulator that controls the generated power of the auxiliary generator, and AC power generated by the main generator is converted into DC power. A rectifier, a DC motor supplied from the rectifier to a variable frequency AC power, a DC motor that converts AC power generated by the traction motor when the vehicle decelerates, and a DC motor An electrical resistor that is electrically connected and converts DC power output from the travel motor inverter when the vehicle decelerates into heat, and controls DC power output to the electrical resistor. A chopper for cooling, a cooler for cooling the electrical resistor, a drive device for the cooler that drives the cooler, and cooling that modulates the frequency of the AC power generated by the auxiliary generator and outputs it to the drive device for the cooler An electric drive type dump truck provided with an inverter for equipment, provided on an output shaft of the travel motor, and at least one generator motor for generating electric power as the output shaft rotates, and on the output side of the auxiliary generator An inverter for a generator motor that is electrically connected and converts the generated power of the generator motor into AC power of variable frequency, and supplies the AC power generated by the generator motor to the output side of the auxiliary generator when the vehicle decelerates And a control device for controlling the operation of the generated power regulator and the inverter for the generator motor so that the generated power of the auxiliary generator is reduced. And butterflies.

  According to the electrically driven dump truck of the present invention, the cooling performance for the resistor can be freely set when the vehicle is decelerated. Problems, configurations, and effects other than those described above will become apparent from the following description of embodiments.

1 is an overall view showing a configuration of an electrically driven dump truck according to a first embodiment of the present invention. It is a figure which shows the basic composition of the drive circuit which drives the dump truck shown in FIG. It is a figure which shows the structure of the principal part of the drive circuit which makes the characteristic of 1st Embodiment of this invention. It is a flowchart which shows the flow of control processing of the auxiliary generator and the generator motor by the control apparatus which concerns on 1st Embodiment of this invention. It is a figure explaining the relationship between the electric power generated by the auxiliary generator and the electric power generated by the generator motor according to the first embodiment of the present invention, and (a) the time of the electric power generated by the auxiliary generator when the generator motor is not used. The figure which shows transition, (b) figure is a figure which shows the time transition of the generated electric power of an auxiliary generator and the generated electric power of a generator motor in case the estimated generated electric power of a generator motor is less than a threshold. It is a figure explaining the relationship between the electric power generated by the auxiliary generator and the electric power generated by the electric motor according to the first embodiment of the present invention, and (a) the figure shows that the predicted electric power generated by the electric motor is equal to or greater than a threshold and the original auxiliary generator The figure which shows the time transition of the generated electric power of an auxiliary generator and the generated electric power of a generator motor when it is less than the generated electric power of FIG. It is a figure which shows the time transition of the generated electric power of an auxiliary generator in the above case, and the generated electric power of a generator motor. It is a figure which shows the structure of the principal part of the drive circuit which makes the characteristics of 2nd Embodiment of this invention. It is a figure which shows the structure of the principal part of the drive circuit which makes the characteristic of 3rd Embodiment of this invention.

  EMBODIMENT OF THE INVENTION Hereinafter, the form for implementing the electrically driven dump truck which concerns on this invention is demonstrated based on figures.

[First Embodiment]
As shown in FIG. 1, the first embodiment of the electrically driven dump truck according to the present invention is a large dump truck 1 that loads and transports earth and sand as a transport object at a work site such as a mine. It is composed of The dump truck 1 includes a body frame 11 and wheels that are rotatably provided on the body frame 11.

  The wheels include, for example, front wheels 12L and 12R (one of the left front wheels 12L only shown in FIG. 1) disposed on the left and right ends of the front portion of the body frame 11, and the rear portion of the body frame 11. The rear wheels 13L and 13R (two left wheels 13L are only shown in FIG. 1) are arranged on each of the left and right ends of the two wheels.

  The front wheels 12L and 12R are steered wheels that are steered based on a steering angle that is input via steering or the like, and are driven by the rear wheels 13L and 13R via the road surface of the traveling path on which the dump truck 1 travels. It is a driving wheel. On the other hand, the rear wheels 13L and 13R are drive wheels that are driven by converting a driving force of an engine 31 (see FIG. 2) described later into a rotational motion.

  Traveling motors 14L and 14R (see FIG. 2) for driving the rear wheels 13L and 13R are attached to the rotation shafts of the rear wheels 13L and 13R, and travel with the rotation shafts of the rear wheels 13L and 13R. Reducers 15L and 15R (see FIG. 2) for adjusting the rotational speed of the rear wheels 13L and 13R are interposed between the output shafts of the motors 14L and 14R. Further, rotational speed sensors 16L and 16R (see FIG. 2) as rotational speed measuring units for measuring the rotational speeds of the traveling motors 14L and 14R are attached to the traveling motors 14L and 14R.

  Further, the dump truck 1 is disposed above the front wheels 12L and 12R, and a deck (upper deck) 17 on which an operator can walk and a ladder 18 that is attached to the front surface of the vehicle so that the operator ascends to the upper surface 17U of the deck 17. A cab 19 that is installed on the upper surface 17U of the deck 17 and on which an operator gets on, a control cabinet 20 that is mounted on the front of the vehicle and houses various power devices, and a drive circuit 30 (described later) of the dump truck 1 (see FIG. 2) and a plurality of grid boxes 21 for dissipating the regenerative power as heat.

  Further, the dump truck 1 is provided so as to be able to rise and fall with respect to the vehicle body frame 11, a loading platform 22 for loading a load such as earth and sand, ore, and a hinge pin 24 provided at a rear portion of the vehicle body frame 11 via a bracket 23, The vehicle body frame 11 includes a hoist cylinder 25 that is disposed in front of the hinge pin 24 and connects the vehicle body frame 11 and the loading platform 22.

  An engine 31, a main generator 32, an auxiliary generator 33, and the like, which will be described later, are mounted on a portion hidden by the front wheel 12L of the dump truck 1, and a control for controlling the operation of the vehicle is provided above these devices. A device 60 is installed. In addition, the dump truck 1 is disposed in the center portion of the vehicle body frame 11 and stores a fuel tank 26 that stores fuel for the engine 31, a hydraulic pump (not shown) that supplies pressure oil to the hoist cylinder 25, A hydraulic oil tank 27 that is disposed near the fuel tank 26 in the frame 11 and stores hydraulic oil supplied to the hydraulic pump is mounted.

  In the cab 19, a hoist pedal (not shown) that is connected to the control device 60 and extends and retracts the hoist cylinder 25 to extend and lower the loading platform 22, forward (F), neutral ( N) and a shift lever (not shown) for switching to either one of the reverse (R) and an operation handle (for changing the traveling direction of the vehicle leftward or rightward by switching the steering direction of the front wheels 12L, 12R) An accelerator pedal (not shown) for accelerating the vehicle, and a brake pedal 28 (see FIG. 2) for applying a braking force to the rear wheels 13L and 13R are installed. Therefore, the operator in the cab 19 can adjust the acceleration force and braking force of the vehicle according to the operation amount by depressing the accelerator pedal and the brake pedal 28.

  Next, the basic configuration of the drive circuit 30 for driving the dump truck 1 according to the first embodiment of the present invention will be described in detail with reference to FIG.

  As shown in FIG. 2, the drive circuit 30 mounted on the dump truck 1 is mechanically connected to an engine 31 as a drive source and an output shaft of the engine 31, and generates power by the driving force of the engine 31. The generator 32 and the auxiliary generator 33 and the respective devices housed in the control cabinet 20 and the grid box 21 are electrically connected to the main generator 32 and the auxiliary generator 33.

  The engine 31 includes a diesel turbo engine having a supercharger (not shown) that supercharges air supplied to each cylinder (not shown), and includes a main generator 32, an auxiliary generator 33, a hoist cylinder 25, and the like. The hydraulic pump, which is the hydraulic power source, is driven. The main generator 32 and the auxiliary generator 33 are connected to the output shaft of the engine 31 and rotate together. The main generator 32 mainly generates three-phase AC power that is a power source for the left and right traveling motors 14L and 14R. The auxiliary generator 33 generates, for example, three-phase AC power serving as a power source for a cooling fan motor 41 described later as auxiliary equipment.

  The control cabinet 20 includes a rectifier 34 that converts AC power generated by the main generator 32 into DC power, an auxiliary generator excitation unit 35 as a generated power regulator that controls the generated power of the auxiliary generator 33, and a rectifier. The left and right traveling motor inverters 36L and 36R for converting the alternating current power generated by the traveling motors 14L and 14R when the vehicle is decelerated into the direct current power are stored. Has been.

  The control cabinet 20 also includes a cooling fan motor inverter 37 as a cooler inverter that frequency-modulates the AC power generated by the auxiliary generator 33 and outputs it to the cooling fan motor 41, a rectifier 34, and a travel motor inverter 36L. , 36R, and a chopper 38 for controlling DC power output to an electric resistor 39 described later is stored.

  The grid box 21 is electrically connected to a rectifier 34 and a chopper 38, and converts the DC power output from the travel motor inverters 36L and 36R into heat when the vehicle is decelerated, and the electric resistor 39. A cooling fan 40 as a cooler that cools the electrical resistor 39 by blowing air to the resistor 39, and a cooler drive that drives the cooling fan 40 with electric power supplied from the cooling fan motor inverter 37 The above-described cooling fan motor 41 as a device and various sensors such as a temperature sensor 42 for measuring the temperature around the electric resistor 39 and switches (not shown) are stored.

  The above-described control device 60 includes, for example, a CPU (Central Processing Unit) that performs various calculations for controlling the entire operation of the vehicle based on information input by the state of the vehicle and the operation of the operator, although not illustrated. A storage device such as a ROM (Read Only Memory) or HDD (Hard Disk Drive) for storing a program for executing a calculation by the CPU, and a RAM (Random Access Memory) as a work area when the CPU executes the program; It is composed of hardware including

  In such a hardware configuration, a program stored in a recording medium such as a ROM, an HDD, or an optical disk (not shown) is read into a RAM, and operates according to the control of the CPU. In cooperation, a functional block for realizing the function of the control device 60 is configured.

  Specifically, the control device 60 inputs the device information such as the operation state of the engine 31, the operation amount of the brake pedal 28, the measured values of the rotational speed sensors 16L and 16R, and the measured values of the temperature sensor 42. And a storage unit 602 that stores information necessary for the arithmetic processing of the CPU in advance, and the information input to the input unit 601 and the information stored in the storage unit 602. A calculation control unit 603 that calculates an operation signal for the device to control the device of the drive circuit 30 and an output unit 604 that outputs a calculation result of the calculation control unit 603 to the device of the drive circuit 30 are included.

  In the first embodiment of the present invention, the control device 60 uses the operation signal calculated by the calculation control unit 603 as the engine 31, the auxiliary generator excitation unit 35, the travel motor inverters 36L and 36R, the cooling fan motor inverter 37, And an appropriate output from the output unit 604 to the semiconductor switch (not shown) of the chopper 38, and the driving motors 14L and 14R, the electric resistor 39, and the cooling fan motor 41 are driven at an appropriate timing and output, thereby driving the driving circuit 30. The flow of power is controlled.

  Next, the flow of power generated by the main generator 32 of the drive circuit 30 will be described in detail with reference to FIG.

  When the main generator 32 is driven by the engine 31, the three-phase AC voltage generated by the main generator 32 is converted into a DC voltage by the rectifier 34 and input to the traveling motor inverters 36L and 36R. In this state, when an operator in the cab 19 depresses the accelerator pedal, an operation signal for accelerating the vehicle is output from the control device 60 to the traveling motor inverters 36L and 36R, and electric power is supplied to the traveling motors 14L and 14R. The

  The traveling motors 14L and 14R are driven by receiving this electric power, thereby rotating the rear wheels 13L and 13R via the speed reducers 15L and 15R to advance or reverse the vehicle. On the other hand, when the operator depresses the brake pedal 28 or the vehicle brakes on a downhill, an operation signal for decelerating the vehicle is output from the control device 60 to the travel motor inverters 36L and 36R, and the travel motors 14L, 14R converts the kinetic energy of the vehicle into electrical energy.

  That is, the traveling motors 14L and 14R function as a generator like the main generator 32 and the auxiliary generator 33, and operate as an electric brake system. At this time, a function for discharging the electric power generated by the traveling motors 14L and 14R is required.

  Therefore, the chopper 38 connected to the travel motor inverters 36L and 36R is operated to apply a DC voltage to the electric resistor 39, so that excess electric energy is consumed as heat. Normally, the electric resistor 39 is naturally air-cooled by the ambient air. However, if the heat generation energy of the electric resistor 39 is large, the temperature of the electric resistor 39 rises and the device of the drive circuit 30 is damaged. there's a possibility that. Therefore, the control device 60 is configured to cool the electrical resistor 39 by forced air cooling by rotating the cooling fan 40 according to the temperature measured by the temperature sensor 42.

  Next, the flow of power generated by the auxiliary generator 33 of the drive circuit 30 will be described in detail with reference to FIG.

  When the auxiliary generator 33 is driven by the engine 31, the auxiliary generator excitation unit 35 controls the generated power of the auxiliary generator 33 according to the operation signal from the control device 60. As a result, the three-phase AC voltage generated by the auxiliary generator 33 is input to the cooling fan motor inverter 37.

  At this time, when the control device 60 determines that the measured value of the temperature sensor 42 input to the input unit 601 is larger than the threshold value stored in advance in the storage unit 602, that is, the electric resistor 39 needs to be cooled. In this case, the arithmetic control unit 603 of the control device 60 obtains the rotational speed of the cooling fan 40 that generates the air volume necessary for cooling the electric resistor 39, and then operates the cooling fan motor 41 that realizes the rotational speed. A signal is calculated and an operation signal corresponding to the generated power of the auxiliary generator 33 necessary for the operation of the cooling fan motor 41 is calculated.

  Then, the control device 60 outputs each operation signal calculated by the calculation control unit 603 from the output unit 604 to the cooling fan motor inverter 37 and the auxiliary generator excitation unit 35, so that the cooling fan motor 41 and the auxiliary generator are output. 33 are operated. As a result, the cooling air generated by the rotation of the cooling fan 40 collides with the electric resistor 39, takes the heat of the electric resistor 39, and releases it to the outside, whereby the electric resistor 39 can be cooled.

  In this way, the dump truck 1 temporarily secures the braking force of the vehicle by converting mechanical braking energy temporarily into electrical energy and further converting the electrical energy into thermal energy using the electrical resistor 39. is doing. Further, the dump truck 1 forcibly air-cools the heat generated by the electric resistor 39 by the cooling fan 40 and releases it to the atmosphere, thereby preventing the equipment of the drive circuit 30 from being damaged and stable braking of the vehicle. Is realized. Although not shown, the dump truck 1 may have a mechanical brake system, and the vehicle may be braked by using either an electric brake system or a mechanical brake system depending on the traveling state of the vehicle. .

  By the way, in the basic configuration of the drive circuit 30 described above, the electric power consumed for the operation of the cooling fan motor 41 is generated by the auxiliary generator 33 directly connected to the output shaft of the engine 31, and the cooling fan 40 operates. In doing so, since additional driving force for driving the auxiliary generator 33 is required for the engine 31, the amount of fuel consumed by the engine 31 increases accordingly. Therefore, the first embodiment of the present invention includes the drive circuit 30 shown in FIG. 3 in which the following devices are newly added instead of the drive circuit 30 having only the basic configuration shown in FIG.

  Next, the configuration of the main part of the drive circuit 30 that characterizes the first embodiment of the present invention will be described in detail with reference to FIG.

  In addition to the basic configuration shown in FIG. 2, the drive circuit 30 according to the first embodiment of the present invention is further provided, for example, on the output shaft of the left travel motor 14L among the travel motors 14L and 14R. It includes a generator motor 50 that generates electric power as it rotates, and an inverter 51 for a generator motor that is electrically connected to the output side of the auxiliary generator 33 and converts the generated power of the generator motor 50 into AC power of variable frequency. .

  The rated rotational speed of the generator motor 50 is set, for example, within the range of the used rotational speed of the traveling motor 14L, and the generator motor 50 is a speed reducer with the main body of the traveling motor 14L among the output shafts of the traveling motor 14L. It is directly connected to the opposite side to 15L. Thereby, the power generation motor 50 is operated by the traveling motor 14L without passing through the speed reducer 15L, so that the energy transmission efficiency in the drive circuit 30 can be increased. The generator motor 50 is electrically connected to a cooling fan motor inverter (cooler inverter) 37 via a generator motor inverter 51, and supplies the generated power of the generator motor 50 to the cooling fan motor inverter 37.

  The generator motor inverter 51 is communicatively connected to the input unit 601 and the output unit 604 of the control device 60. In addition, as will be described later, predetermined specifications relating to the power generation motor 50, for example, the number of turns of the coil of the power generation motor 50 and the strength of the magnetic field are stored in the storage unit 602 of the control device 60 in advance.

  The control device 60 operates the engine 31, the operation amount of the brake pedal 28, the measured values of the rotation speed sensors 16L and 16R, the measured value of the temperature sensor 42, the current and voltage of the generator motor inverter 51, and the like. The auxiliary generator excitation unit 35 is obtained so that the AC power generated by the generator motor 50 during deceleration of the vehicle is supplied to the output side of the auxiliary generator 33 to reduce the generated power of the auxiliary generator 33. And the operation of the generator motor inverter 51 is controlled.

  Next, control processing of the auxiliary generator 33 and the generator motor 50 by the control device 60 according to the first embodiment of the present invention will be described in detail with reference to the flowchart of FIG.

  As shown in FIG. 4, first, the input unit 601 of the control device 60 includes device information including an operation amount BM of the brake pedal 28, measured values of the rotation speed sensors 16 </ b> L and 16 </ b> R, and a current and a voltage of the generator motor inverter 51. (Step (hereinafter referred to as “S”) 401), and transfers the device information to the arithmetic control unit 603 of the control device 60.

  Next, the arithmetic control unit 603 generates the generated power of the auxiliary generator 33 of the drive circuit 30 having only the basic configuration shown in FIG. 2, that is, the generated power Pago of the original auxiliary generator 33 not using the generator motor 50. It sets so that it may become the electric power PFN required for operation | movement of the cooling fan motor 41 computed as mentioned above (Pago = PFN) (S402).

  Subsequently, the arithmetic control unit 603 is based on the number of turns of the coil of the power generation motor 50 and the strength of the magnetic field stored in the storage unit 602 and the traveling motors 14L and 14R measured by the rotation speed sensors 16L and 16R. An expected generated power Pgmf indicating the generated power of the generator motor 50 expected when the vehicle is decelerated is calculated (S403). That is, the calculation control unit 603 functions as an expected generated power calculation unit, and the rotation speed sensors 16L and 16R, the storage unit 602, and the calculation control unit 603 function as an expected generated power acquisition unit.

  Next, the arithmetic control unit 603 determines whether or not the operation amount BM of the brake pedal 28 acquired in S401 is greater than or equal to a preset threshold value TB (S404). At this time, when it is determined that the operation amount BM of the brake pedal 28 is less than the threshold value TB (S404 / NO), the arithmetic control unit 603 uses the generated power Pag of the auxiliary generator 33 as the generated power Pago of the original auxiliary generator. (Pag = Pago) (S405).

  Subsequently, the arithmetic control unit 603 sets the generated power Pgm of the generator motor 50 to 0 (Pgm = 0) (S406). That is, the power generated by the auxiliary generator 33 becomes equal to the power generated by the auxiliary generator 33 of the drive circuit 30 having only the basic configuration shown in FIG. Control processing is performed.

  Next, the calculation control unit 603 calculates and generates an operation signal of the auxiliary generator excitation unit 35 corresponding to the generated power Pag of the auxiliary generator 33 (S407), and then corresponds to the generated power Pgm of the generator motor 50. An operation signal of the generator motor inverter 51 is calculated and generated (S408), and these calculation results are transmitted to the output unit 604 of the control device 60.

  When receiving the calculation result of the calculation control unit 603, the output unit 604 outputs the operation signal generated in S407 to the auxiliary generator excitation unit 35 and outputs the operation signal generated in S408 to the generator motor inverter 51. (S409), and the control process of the auxiliary generator 33 and the generator motor 50 by the control device 60 is terminated.

  On the other hand, in S404, when the calculation control unit 603 determines that the operation amount BM of the brake pedal 28 is equal to or larger than the threshold value TB (S404 / YES), the predicted generated power Pgmf calculated in S403 and the preset threshold value TG To determine whether the predicted generated power Pgmf is greater than or equal to the threshold TG (S410). At this time, if the arithmetic control unit 603 determines that the predicted generated power Pgmf is less than the threshold value TG (S410 / NO), the processing from S405 is performed.

  On the other hand, in S410, if the arithmetic control unit 603 determines that the predicted generated power Pgmf is equal to or greater than the threshold TG (S410 / YES), is the predicted generated power Pgmf equal to or greater than the original generated power Pago of the auxiliary generator 33? It is determined whether or not (S411). At this time, when the arithmetic control unit 603 determines that the predicted generated power Pgmf is less than the generated power Pago of the original auxiliary generator 33 (S411 / NO), the calculated control power Pgmf determines the generated power Pag of the auxiliary generator 33 as the original auxiliary generator. A value obtained by subtracting the predicted generated power Pgmf from the generated power Pago of 33 is set (Pag = Pago−Pgmf) (S412). By the process of S412, it becomes possible to reduce the generated power of the auxiliary generator 33 by the power generated by the generator motor 50 from the original generated power of the auxiliary generator 33.

  Subsequently, the arithmetic control unit 603 sets the generated power Pgm of the generator motor 50 to the predicted generated power Pgmf (Pgm = Pgmf) (S413), and the processing from S407 is performed. On the other hand, if the calculation control unit 603 determines in S411 that the predicted generated power Pgmf is greater than or equal to the original generated power Pago of the auxiliary generator 33 (S411 / YES), the generated power Pag of the auxiliary generator 33 is set to 0 (zero). ) (Pag = 0) (S414).

  Subsequently, the arithmetic control unit 603 sets the generated power Pgm of the generator motor 50 to the original generated power Pago of the auxiliary generator 33 (Pgm = Pago) (S415), and the processing from S407 is performed. Therefore, in the drive circuit 30 having the basic configuration shown in FIG. 2, all the power originally generated by the auxiliary generator 33 is generated by the generator motor 50 without generating the auxiliary generator 33 by the processing of S414 and S415. It can generate electricity.

  In an open pit mine, the mining site is gradually dug down into a mortar shape, so that the dump truck 1 carrying the mined resources travels down to the bottom of the mortar-shaped mining site. The traveling path of the dump truck 1 is spirally provided on the slope of the mortar, and its length often reaches several kilometers or more. Accordingly, the dump truck 1 travels while turning in the same direction for most of the descending travel time. For example, when the dump truck 1 travels counterclockwise, the rotational speed on the outer ring side is larger in the traveling motor 14L on the inner ring side and the traveling motor 14R on the outer ring side. Further, the tread width of the large dump truck 1 is generally 5 to 6 m, and the traveling distance difference between the inner and outer wheels is large in that respect. For this reason, the difference in regenerative electric energy between the inner-wheel side travel motor 14L and the outer-wheel-side travel motor 14R when traveling down is so large that it cannot be ignored, so one of the two generation motors 14L, 14R ( In FIG. 3, the regenerative operation of the left and right traveling motors 14L, 14R can be made uniform simply by being attached to the left traveling motor 14L).

  Next, the relationship between the generated power of the auxiliary generator 33 and the generated power of the generator motor 50 according to the first embodiment of the present invention will be described in detail with reference to FIGS. 5 and 6. In FIGS. 5 and 6, the broken line is the original generated power Pago of the auxiliary generator 33, the solid line is the generated power Pag of the auxiliary generator 33, the dotted line is the expected generated power Pgmf of the generator motor 50, and the alternate long and short dash line is the generated power of the generator motor 50. Electric power Pgm is shown respectively.

  FIG. 5A shows a time transition of the generated power Pag of the auxiliary generator 33 when the generator motor 50 is not used. In this case, in the dump truck 1 including the drive circuit 30 having only the basic configuration shown in FIG. 2, the load of the auxiliary generator 33 varies greatly according to the required load of the cooling fan motor 41. Generated power Pag changes. The generated power Pag of the auxiliary generator 33 in this case means the original generated power Pago of the auxiliary generator 33.

  FIG. 5B shows a time transition of the generated power Pag of the auxiliary generator 33 and the generated power Pgm of the generator motor 50 when the predicted generated power Pgmf of the generator motor 50 is less than the threshold TG. In this case, since the generated power Pgm of the power generation motor 50 is 0 (zero), the regenerative operation by the power generation motor 50 is not performed, and all the power for driving the cooling fan motor 41 is supplied from the auxiliary generator 33.

  As a result, the generated power Pag of the auxiliary generator 33 is the same as the original generated power Pago of the auxiliary generator 33, and the generated power changes in the same manner as in FIG. Further, since the generated power Pgm of the power generation motor 50 is 0 (zero), a load due to power generation by the power generation motor 50 is not generated, and the load of the power generation motor 50 is not applied to the traveling motor 14L. Therefore, the load applied to the engine 31 is the same as when the drive circuit 30 has only the basic configuration, and the fuel consumption of the engine 31 is the same as when the drive circuit 30 has only the basic configuration. Note that the operation of the drive circuit 30 illustrated in FIG. 5B corresponds to S405 to S409 illustrated in FIG.

  FIG. 6A shows the generated power Pag of the auxiliary generator 33 and the generated power of the generator motor 50 when the predicted generated power Pgmf of the generator motor 50 is greater than or equal to the threshold TG and less than the original generated power Pago of the auxiliary generator 33. The time transition of Pgm is shown. In this case, all of the power generated by the generator motor 50 is regenerated, and the generated power Pag of the auxiliary generator 33 is a value obtained by subtracting the expected generated power Pgmf of the generator motor 50 from the original generated power Pago of the auxiliary generator 33. Thus, the generated electric power Pago of the auxiliary generator 33 becomes smaller.

  As a result, the load applied to the engine 31 with the power generation of the auxiliary generator 33 is reduced, so that the fuel consumption of the engine 31 is reduced. The operation of the drive circuit 30 shown in FIG. 6A corresponds to S412, S413, and S407 to S409 shown in FIG.

  FIG. 6B shows the generated power Pag of the auxiliary generator 33 and the generated power of the generator motor 50 when the predicted generated power Pgmf of the generator motor 50 is not less than the threshold TG and not less than the original generated power Pago of the auxiliary generator 33. The time transition of Pgm is shown. In this case, since the generated power Pgm of the generator motor 50 is set equal to the original generated power Pago of the auxiliary generator 33, the generated power Pag of the auxiliary generator 33 is 0 (zero).

  As a result, the load applied to the engine 31 with the power generation of the auxiliary generator 33 is reduced, so that the fuel consumption of the engine 31 is reduced. The operation of the drive circuit 30 shown in FIG. 6B corresponds to S414, S415, and S407 to S409 shown in FIG.

  According to the dump truck 1 according to the first embodiment of the present invention configured as described above, when the vehicle decelerates, the traveling motors 14L and 14R are used as retarders to generate power, and the power generation motor 50 is generated. Is supplied from the generator motor inverter 51 to the cooling fan motor inverter 37, so that the electric motor 39 sufficiently cools the electric resistor 39 by the cooling fan 40 while supplementing the power generation of the auxiliary generator 33. be able to. Thereby, since the output of the engine 31 can be suppressed by reducing the load of the auxiliary generator 33, the fuel consumption of the engine 31 when the vehicle is decelerated can be reduced.

  In the dump truck 1 according to the first embodiment of the present invention, the calculation control unit 603 of the control device 60 determines that the calculated predicted generated power Pgmf of the generator motor 50 is equal to or greater than a preset threshold TG. Since the auxiliary generator excitation unit 35 is controlled so as to decrease the generated power Pag of the auxiliary generator 33, the power generation of the auxiliary generator 33 and the power generation of the power generation motor 50 are not frequently switched. , Fluctuations in the output of the engine 31 and the main generator 32 can be suppressed. As a result, the engine 31, the main generator 32, the auxiliary generator 33, and the generator motor 50 can be prevented from being damaged, so that the life of these devices can be extended.

  In the dump truck 1 according to the first embodiment of the present invention, the arithmetic control unit 603 of the control device 60 stores the rotational speeds of the traveling motors 14L and 14R measured by the rotational speed sensors 16L and 16R and the storage unit 602. Since the predicted generated power Pgmf of the generator motor 50 is calculated from the generated information, the estimated value of the generated power of the generator motor 50 obtained when the vehicle decelerates can be obtained efficiently. Therefore, the processing capability of the control device 60 required for controlling the auxiliary generator 33 and the generator motor 50 can be improved.

  Further, in the dump truck 1 according to the first embodiment of the present invention, when the arithmetic control unit 603 of the control device 60 determines that the operation amount BM of the brake pedal 28 is equal to or larger than the threshold value TB, S410 shown in FIG. Since the processing is shifted to the subsequent processing, for example, while the vehicle is traveling on a slope such as a slope, the operability of the vehicle is improved by the operation of the generator motor 50 and the load applied to the traveling motor 14L. Deterioration can be prevented in advance. That is, since the control to cut off the supply of electric power from the power generation motor 50 is performed during the power running operation of the travel motor 14L, the load on the travel motor 14L resulting from the power generation operation of the power generation motor 50 can be reduced, and the travel resistance of the vehicle is reduced. can do.

  In the dump truck 1 according to the first embodiment of the present invention, the generator motor 50 is connected to one of the output shafts of the traveling motor 14L on the side opposite to the speed reducer 15L, so that the regenerative operation of the traveling motor 14L is performed. Sometimes, the power generation motor 50 can obtain an appropriate amount of electric power, and an increase in the number of devices in the drive circuit 30 can be suppressed to secure a maintenance space in the vehicle. In particular, when the dump truck 1 ascends or descends the mine traveling path clockwise, the generator motor 50 is directly connected to the left traveling motor 14L, so that the power generation motor 50 generates power. Efficiency can be increased.

  In addition, the dump truck 1 according to the first embodiment of the present invention uses electric energy obtained in the regenerative operation of the traveling motor 14L as driving power for the cooling fan 40, and is unsteady like when the vehicle is decelerated. Can be used effectively without temporarily storing the generated power. Furthermore, the dump truck 1 according to the first embodiment of the present invention can be used for a vehicle regeneration system by simply adding a generator motor 50 and a generator motor inverter 51 without changing the basic configuration of the drive circuit 30. Can be realized. Therefore, even if the generator motor 50 and the inverter 51 for the generator motor are damaged, the running performance of the vehicle is not deteriorated, so that excellent stability with respect to the running of the vehicle can be ensured. .

[Second Embodiment]
In addition to the configuration of the first embodiment described above, the dump truck 1 according to the second embodiment of the present invention includes a drive circuit 30A interposed between the traveling motor 14L and the generator motor 50 as shown in FIG. In addition, a coupling 52 that transmits the rotation of the output shaft of the traveling motor 14L to the generator motor 50 is included. Since the other configurations of the second embodiment are the same as those of the first embodiment described above, the same or corresponding parts as those of the first embodiment are denoted by the same reference numerals, and redundant description is omitted.

  In the drive circuit 30 </ b> A configured as described above, when the traveling motor 14 </ b> L rotates, the coupling 52 also interlocks with the rotation of the traveling motor 14 </ b> L, so the power generation motor 50 also rotates through the coupling 52. At this time, if a fluctuation occurs in the rotational speed of the traveling motor 14L, the coupling 52 is deformed to absorb the fluctuation in the rotational speed of the traveling motor 14L, so that the generator motor 50 rotates at a rotational speed in which the fluctuation is suppressed. . In addition, the coupling 52 which concerns on 2nd Embodiment of this invention does not limit the kind and system.

  According to the dump truck 1 according to the second embodiment of the present invention configured as described above, the same effects as those of the first embodiment described above can be obtained, and the coupling 52 can be connected between the traveling motor 14L and the generator motor 50. Since it is interposed, it is possible to suppress the fluctuation of the rotational speed of the traveling motor 14L from being transmitted to the power generation motor 50, and the load applied to the power generation motor 50 can be reduced. Thereby, it is possible to contribute to extending the life of the generator motor 50. Further, when either one of the traveling motor 14L and the generator motor 50 fails, the coupling 52 is damaged, so that the other device can be prevented from being damaged.

[Third Embodiment]
In addition to the configuration of the first embodiment described above, the dump truck 1 according to the third embodiment of the present invention includes a drive circuit 30B interposed between the traveling motor 14L and the generator motor 50 as shown in FIG. And includes a clutch 53 that connects the output shaft of the traveling motor 14L and the input shaft of the generator motor 50 in an intermittent manner. In this case, the control device 60 acquires device information such as the operating state of the engine 31, the operation amount BM of the brake pedal 28, the measured values of the rotation speed sensors 16L and 16R, and the measured value of the temperature sensor 42. Based on this, the operation of the clutch 53 is controlled. Since the other configurations of the third embodiment are the same as those of the first embodiment described above, the same or corresponding parts as those of the first embodiment are denoted by the same reference numerals, and redundant description is omitted.

  In the drive circuit 30 </ b> B configured as described above, when the traveling motor 14 </ b> L rotates, the clutch 53 also interlocks with the rotation of the traveling motor 14 </ b> L, and thus the power generation motor 50 also rotates via the clutch 53. The control device 60 sets the generated power Pgm of the power generation motor 50 to 0 (zero) to prevent the power generation motor 50 from generating power as in the process of S406 shown in FIG. When it is determined that at least one of the connected device, the generator motor 50, and the device connected to the generator motor 50 has failed, control is performed to disengage the clutch 53, whereby the output shaft of the travel motor 14L and the generator The input shaft of the motor 50 is disconnected. In addition, the clutch 53 which concerns on 3rd Embodiment of this invention does not limit the kind and system.

  According to the dump truck 1 according to the third embodiment of the present invention configured as described above, the control device 60 determines that the generator motor 50 does not generate power, in addition to obtaining the same operational effects as the first embodiment described above. At this time, the output shaft of the traveling motor 14L and the input shaft of the generator motor 50 are disconnected, so that the load of the generator motor 50 is not transmitted to the traveling motor 14L. Therefore, an increase in the output of the engine 31 can be suppressed, so that the fuel consumption of the engine 31 can be effectively reduced.

  In addition, when at least one of the travel motor 14L, the device connected to the travel motor 14L, the power generation motor 50, and the device connected to the power generation motor 50 breaks down, the clutch 53 is disconnected by the control device 60. It is possible to prevent these devices from being damaged by being linked to a failed device.

  The above-described embodiments of the present invention have been described in detail for easy understanding of the present invention, and are not necessarily limited to those having all the configurations described. Further, a part of the configuration of an embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of an embodiment.

  Moreover, although this embodiment demonstrated the case where the electric power generated with the auxiliary generator 33 was mainly used in order to drive the cooling fan motor 41, this invention is not limited to this case, and with the auxiliary generator 33, The generated power may be used to operate other auxiliary machines. Similarly, in the present embodiment, the case where the power generated by the power generation motor 50 is mainly used to drive the cooling fan motor 41 has been described. However, the present invention is not limited to this case, and the power generation by the power generation motor 50 is performed. The generated power may be used to operate other accessories. As an effect obtained at this time, it is possible to reduce the fuel consumption of the engine by covering the energy for operating the auxiliary equipment with regenerative power.

  Moreover, although this embodiment demonstrated the case where the generator motor 50 was connected with the output shaft of one traveling motor 14L among the left and right traveling motors 14L and 14R, the present invention is not limited to this case, and the generator motor 50 is not limited thereto. May be connected to the other travel motor 14R, or two power generation motors 50 may be prepared, and these power generation motors 50 may be connected to both travel motors 14L and 14R.

DESCRIPTION OF SYMBOLS 1 ... Dump truck (electrically driven dump truck), 12L, 12R ... Front wheel (wheel), 13L, 13R ... Rear wheel (wheel), 14L, 14R ... Travel motor, 15L, 15R ... Reduction gear, 16L, 16R ... Rotation Speed sensor (rotational speed measuring unit) (predicted power generation acquisition unit), 19 ... cab, 20 ... control cabinet, 21 ... grid box, 28 ... brake pedal 30, 30A, 30B ... drive circuit, 31 ... engine, 32 ... main Generator 33 ... auxiliary generator 34 ... rectifier 35 ... auxiliary generator excitation unit (generated power regulator) 36L, 36R ... travel motor inverter 37 ... cooling fan motor inverter (cooler inverter) 38 ... Chopper, 39 ... Electric resistor, 40 ... Cooling fan (cooler), 41 ... Cooling fan motor (drive device for cooler) ), 42 ... Temperature sensor 50 ... Generator motor, 51 ... Inverter for generator motor, 52 ... Coupling, 53 ... Clutch, 60 ... Control device, 601 ... Input unit, 602 ... Storage unit (expected generation power acquisition unit), 603 ... Calculation control unit (expected generation power calculation unit) (expected generation power acquisition unit), 604 ... output unit

Claims (7)

An engine provided in the vehicle, two traveling motors that drive the wheels of the vehicle individually by driving left and right, a main generator and auxiliary power generation that are provided on the output shaft of the engine and generate electric power with the driving force of the engine A generator, a power generator for controlling the power generated by the auxiliary generator, a rectifier for converting AC power generated by the main generator into DC power, and a DC power supplied from the rectifier with a variable frequency AC. A travel motor inverter that converts AC power generated by the travel motor when the vehicle decelerates into DC power, and that is electrically connected to the rectifier and that is used when the vehicle decelerates. An electrical resistor that converts the DC power output from the heat into heat, a chopper that controls the DC power output to the electrical resistor, and a cooling that cools the electrical resistor And a cooler drive device for driving the cooler, and a cooler inverter for frequency-modulating the AC power generated by the auxiliary generator and outputting it to the cooler drive device. And
At least one power generation motor that is provided on the output shaft of the travel motor and that generates electric power as the output shaft rotates;
An inverter for a generator motor that is electrically connected to the output side of the auxiliary generator and converts the generated power of the generator motor into AC power of variable frequency;
The generated power regulator and the generator motor inverter are configured so that the AC power generated by the generator motor during deceleration of the vehicle is supplied to the output side of the auxiliary generator to reduce the generated power of the auxiliary generator. An electrically driven dump truck comprising a control device for controlling operation. The electrically driven dump truck according to claim 1,
One electric motor is provided, and the electric motor is provided on the output shaft of one of the left and right individual traveling motors. The electrically driven dump truck according to claim 1,
An expected generated power acquisition unit for acquiring predicted generated power indicating the generated power of the generator motor expected at the time of deceleration of the vehicle;
The control device compares the predicted generated power acquired by the predicted generated power acquisition unit with a preset threshold and only determines that the predicted generated power is equal to or greater than the threshold. An electrically driven dump truck, wherein an operation signal for reducing the generated power of the machine is transmitted to the generated power regulator. The electrically driven dump truck according to claim 3,
The predicted generated power acquisition unit is
A rotational speed measuring unit for measuring the rotational speed of the traveling motor;
A storage unit in which predetermined specifications relating to the generator motor are stored in advance;
It is composed of a rotational speed of the traveling motor measured by the rotational speed measuring unit and an predicted generated power calculating unit that calculates the predicted generated power from the predetermined specifications stored in the storage unit. Electric driven dump truck. The electrically driven dump truck according to claim 3,
A brake pedal for applying braking force to the vehicle;
The control device determines whether or not the vehicle is decelerating based on the operation amount of the brake pedal, and when the vehicle is decelerating, obtains the predicted generated power acquisition unit The electric drive type dump truck characterized by comparing said predicted generated electric power and said threshold value. The electrically driven dump truck according to claim 1,
A speed reducer that is attached to the output shaft of the travel motor and decelerates the rotation of the output shaft and transmits it to the wheels;
The electric drive type dump truck, wherein the generator motor is directly connected to the opposite side of the speed reducer across the main body of the travel motor of the output shaft of the travel motor. The electrically driven dump truck according to claim 1,
The electric drive type dump truck, wherein the power generation motor is electrically connected to the cooler inverter and supplies the generated power of the power generation motor to the cooler inverter.