Electrically powered vehicles

Abstract

To provide an electrically driven vehicle that is reducible in fuel consumption by increasing chances of generation of regenerative electric power by a travel motor.SOLUTION: A controller 100 detects, as an inertial travel state, a state in which neither an accelerator pedal 70 nor a brake pedal 71 is operated and a vehicle speed is equal to or larger than a predetermined threshold F, controls travel inverters 33, 34 on detecting the inertial travel state to generate regenerative electric power by the travel motors 35, 36, and then controls inverters 43 to 46 for auxiliary equipment so that a converter 60 is operated to supply the regenerative electric power to motors 47 to 50 for auxiliary equipment.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an electrically driven vehicle such as a dump truck. [Background technology]

[0002] Dump trucks are electrically driven vehicles that are based on a four-wheeled body, with the driver's cab and control box located at the front upper part of the body frame, the power unit consisting of an engine, generator and hydraulic pump located at the front lower part of the body frame, a rear axle consisting of a travel motor and reduction gear etc. located at the rear lower part of the body frame, and a loading platform that can be raised and lowered by a hydraulic cylinder from the center to the rear of the upper part of the body frame, and the loading platform is used to transport large quantities of crushed stone, soil or other materials.

[0003] To load a dump truck, a large amount of transported materials is loaded onto the loading section using a dumping machine (e.g., a hydraulic excavator). After the dump truck has transported the materials to its destination and is traveling, the hydraulic cylinder is extended to raise and lower the loading platform around the hinge pin, releasing the materials and completing the transport. The dump truck then returns to the loading area and repeats the process.

[0004] The dump truck described above runs by generating electricity using a main generator powered by the engine, which is then sent to an electric motor in the rear axle by an inverter and a controller to drive the electric motor, which then rotates the tires via a reduction gear, allowing the truck to move. When slowing down or stopping, the truck uses a means of decelerating by regenerative braking using the electric motor (electric brake). The regenerative power generated is passed through the heating resistor of the heating brake resistor device, converted into heat, and then the heat is exhausted to the outside by a fan.

[0005] In addition, the generator and traction motor generate heat when driven, so they need to be cooled, and a cooling system is installed. The cooling system is mainly air-cooled, with a cooling blower driven by an electric motor to blow cooling air. The driving power is generated by an auxiliary generator separate from the main generator, and the auxiliary electric motor is driven and controlled by an inverter and controller so that the object to be cooled is kept below a desired temperature.

[0006] Prior art documents disclosing dump truck technology include, for example, Patent Documents 1 and 2. The hybrid dump truck described in Patent Document 1 stores generated electricity or regenerated electricity during deceleration in a storage battery, and discharges the electricity during acceleration to drive an electric motor to travel.

[0007] Furthermore, when the hybrid vehicle described in Patent Document 2 is traveling downhill on a slope where no driving force is required, and charges the storage battery with regenerative power generated during electric braking in auto-cruise mode, the regenerative power is used to drive an electric pump (auxiliary equipment) and consumes the regenerative power before the storage battery's charge capacity overflows. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-299901 [Patent Document 2] Japanese Patent Application Laid-Open No. 2017-30595 Summary of the Invention [Problem to be solved by the invention]

[0009] As described above, dump trucks, which are electrically driven vehicles, operate to transport loads by accelerating, driving, decelerating, stopping, etc., using the driving and braking of a travel motor, but it is desirable to operate dump trucks while reducing their fuel consumption. To achieve this, effective use of energy in the vehicle drive system is required. Here, as in Patent Documents 1 and 2, it is possible to reduce fuel consumption by installing a storage battery, charging the storage battery with regenerative power generated during electric braking, and using the charged power to drive the motor through charge and discharge control of the storage battery. However, installing a storage battery reduces the load capacity of the transported object by the mass of the storage battery, thereby reducing transportation efficiency.

[0010] To maintain the load capacity of the transported object, it is necessary to have no or a small amount of storage batteries. However, needless to say, if a storage battery is not installed, it is not possible to store regenerative power during electric braking, and the fuel consumption reduction effect cannot be obtained. Or, if the storage battery is small, only a small amount of regenerative power can be stored, and some of the charge / discharge energy is converted into heat due to charge / discharge losses of the storage battery, so fuel consumption reduction is limited.

[0011] On the other hand, there is a method of using the regenerative power generated during electric braking directly to power other auxiliary machinery, rather than storing it in a storage battery. This is energy efficient because there is no charge / discharge loss associated with using a storage battery, but the effect of reducing fuel consumption is limited because the electric braking time is limited.

[0012] In summary, to solve the problem of reducing fuel consumption in electrically driven dump trucks, it is necessary to increase the opportunities to generate regenerative power and immediately use it as auxiliary power, rather than storing the regenerative power generated during electric braking in a large-capacity storage battery or prioritizing storing the power in a storage battery.

[0013] The present invention has been made in consideration of the above-mentioned problems, and its purpose is to provide an electrically driven vehicle that can reduce fuel consumption by increasing opportunities for the traction motor to generate regenerative power. [Means for solving the problem]

[0014] In order to achieve the above object, the present invention provides an engine and a a main generator and an auxiliary generator; and a main rectifier that converts the power generated by the main generator into DC power. an auxiliary rectifier that converts the power generated by the auxiliary generator into DC power; a main circuit to which electric power is supplied, an auxiliary circuit to which DC power is supplied from the auxiliary rectifier, and a running a driving motor, and a driving circuit for converting DC power of the main circuit into AC power and supplying the AC power to the driving motor. an inverter, an auxiliary motor, and a power supply for converting DC power of the auxiliary circuit into AC power to supply the auxiliary an auxiliary inverter that supplies DC power to the auxiliary motor; an accelerator pedal for instructing the driving motor to increase its speed; a brake pedal that instructs the motor to decelerate, and a brake pedal that controls the accelerator pedal and the brake pedal. In response to the input signal from the inverter, the main generator, the auxiliary generator, the driving inverter, The inverter for the auxiliary equipment and a controller for controlling the converter are provided. When the brake pedal is operated, the traction motor generates regenerative power. In an electrically driven vehicle, the vehicle speed is detected by controlling the inverter for driving the vehicle. a vehicle speed sensor, and the controller A state in which none of the above is operated and the vehicle speed is equal to or greater than a predetermined threshold is called a coasting state. When the coasting state is detected, the traveling motor generates regenerative power. The inverter for driving is controlled so as to operate the converter, and the regenerative power is Supply to the auxiliary inverter At the same time, the drive power of the auxiliary motor is calculated, and the driving inverter is controlled so that the regenerative power matches the drive power. It shall be.

[0015] According to the present invention configured as described above, regenerative power can be generated by the traction motor when the vehicle is coasting with neither the accelerator pedal nor the brake pedal depressed, and this regenerative power can be used to provide at least a portion of the drive power for the auxiliary motors. As a result, power generation by the auxiliary generator is suppressed, reducing the load on the engine and enabling improved fuel economy. [Effects of the Invention]

[0016] According to the electrically driven vehicle of the present invention, it is possible to reduce fuel consumption by increasing the opportunities for the traction motor to generate regenerative electric power. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a schematic diagram of a dump truck according to a first embodiment of the present invention; [Figure 2] 1 is a diagram showing the configuration of an electric drive system according to a first embodiment of the present invention; [Figure 3] 1 is a control flow diagram of an electric drive system according to a first embodiment of the present invention; [Figure 4] 1 is a block diagram of an electric drive system according to a second embodiment of the present invention; [Figure 5] 1 is a control flow diagram of an electric drive system according to a second embodiment of the present invention; [Figure 6] 10 is a diagram showing the configuration of an electric drive system according to a third embodiment of the present invention; [Figure 7] 10 is a control flow diagram of an electric drive system according to a third embodiment of the present invention. [Figure 8] 10 is a block diagram of an electric drive system according to a fourth embodiment of the present invention; [Figure 9] 10 is a control flow diagram of an electric drive system according to a fourth embodiment of the present invention. [Figure 10] 10 is a diagram showing the configuration of an electric drive system according to a fifth embodiment of the present invention; [Figure 11] 10 is a control flow diagram of an electric drive system according to a fifth embodiment of the present invention. [Figure 12]10 is a diagram showing the configuration of an electric drive system according to a sixth embodiment of the present invention; [Figure 13] 10 is a control flow diagram of an electric drive system according to a sixth embodiment of the present invention. [Figure 14] 10 is a diagram showing the configuration of an electric drive system according to a seventh embodiment of the present invention. [Figure 15] 10 is a control flow diagram of an electric drive system according to a seventh embodiment of the present invention. [Figure 16] 10 is a diagram showing the configuration of an electric drive system according to an eighth embodiment of the present invention. [Figure 17] 10 is a control flow diagram of an electric drive system according to an eighth embodiment of the present invention. [Figure 18] 13 is a diagram showing the configuration of an electric drive system according to a ninth embodiment of the present invention. [Figure 19] 10 is a control flow diagram of an electric drive system according to a ninth embodiment of the present invention. [Figure 20] 10 is a block diagram of an electric drive system according to a tenth embodiment of the present invention. [Figure 21] 10 is a control flow diagram of an electric drive system according to a tenth embodiment of the present invention. [Figure 22] 11 is a block diagram of an electric drive system according to an eleventh embodiment of the present invention. [Figure 23] 11 is a control flow diagram of an electric drive system according to an eleventh embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0018] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In each drawing, the same elements are designated by the same reference numerals, and duplicate explanations will be omitted as appropriate. In this embodiment, the electrically driven vehicle according to the present invention is applied to a dump truck, but the application of the present invention is not limited to this. [Example]

[0019] Fig. 1 is a side view of a dump truck according to a first embodiment of the present invention. As shown in Fig. 1, the dump truck comprises a body frame 1 and a bed 3 on which a load 2 such as earth and sand is placed. The body frame 1 and the bed 3 are connected by a hoist cylinder 4 and a hinge pin 5. By extending and retracting the hoist cylinder 4, the bed 3 rotates vertically relative to the body frame 1 with the hinge pin 5 as a fulcrum, allowing the load 2 to be dumped.

[0020] Left and right front wheels 6L, 6R, left and right rear wheels 7L, 7R, a hydraulic oil tank (not shown), etc. are attached via mechanical parts (not shown) to the body frame 1. Travel motors 35, 36 (shown in FIG. 2) that drive the rear wheels 7L, 7R and reducers that adjust the rotation speed of the rear wheels 7L, 7R are housed in the rotating shafts of the rear wheels 7L, 7R.

[0021] The dump truck also has a pair of front wheel suspension cylinders 9L, 9R on the front side of the body frame 1, and a pair of rear wheel suspension cylinders 10L, 10R on the rear side of the body frame 1. The front wheel suspension cylinders 9L, 9R are independent suspension cylinders that can raise and lower the left and right front wheels 6L, 6R independently, and their upper ends are attached to the body frame 1 and their lower ends are attached to wheel support members (not shown) that support the left and right front wheels 6L, 6R. The rear wheel suspension cylinders 10L, 10R are independent suspension cylinders that can raise and lower the left and right rear wheels 7L, 7R independently, and their upper ends are attached to the body frame 1 and their lower ends are attached to wheel support members (not shown) that support the left and right rear wheels 7L, 7R.

[0022] A deck 11 on which an operator can walk is attached to the front side of the body frame 1. On the upper surface of the deck 11, there are mounted a cab 12 on which the operator rides to operate the dump truck, a control cabinet 13 that houses various types of power equipment, a grid box 14 for dissipating excess energy from the control cabinet 13 as heat, etc. In addition, in an area hidden by the front wheels 6L, 6R, there is mounted a power unit 15 that includes a main generator 30, an auxiliary generator 40 (both shown in FIG. 2), a main pump (not shown) that serves as a hydraulic pressure source for hydraulic equipment, etc.

[0023] Fig. 2 is a configuration diagram of the electric drive system of this embodiment. In Fig. 2, the electric drive system includes an engine 20, a main generator 30, a main rectifier 31, a main circuit 32, traction inverters 33 and 34, traction motors 35 and 36, a chopper 37, a thermal resistor 38, an auxiliary generator 40, an auxiliary rectifier 41, an auxiliary circuit 42, auxiliary inverters 43 to 46, auxiliary motors 47 to 50, a converter 60, an accelerator pedal 70, a brake pedal 71, a vehicle speed sensor 72, and a controller 100.

[0024] The main generator 30 and the auxiliary generator 40 are driven by the engine 20. The main rectifier 31 converts the power generated by the main generator 30 into DC power and supplies it to the main circuit 32. The auxiliary rectifier 41 converts the power generated by the auxiliary generator 40 into DC power and supplies it to the auxiliary circuit 42. The power and voltage of the main circuit 32 and the auxiliary circuit 42 are significantly different, with the main circuit 32 having a higher power and voltage.

[0025] The traction inverters 33, 34 convert DC power from the main circuit 32 into AC power and supply it to the traction motors 35, 36. The traction motors 35, 36 drive the rear wheels 7L, 7R, which are drive wheels, via a speed reducer (not shown). Operating the traction motors 35, 36 as generators also applies electric braking force to the rear wheels 7L, 7R, slowing the vehicle. Regenerative power generated by the traction motors 35, 36 is converted to DC power by the traction inverters 33, 34 and supplied to the main circuit 32. Most of the regenerative power supplied to the main circuit 32 is supplied to a thermal resistor 38 via a chopper 37 and converted to heat by the thermal resistor 38. The remaining regenerative power is supplied to the auxiliary circuit 42 via a converter 60. The regenerative power supplied to the auxiliary circuit 42 is converted to AC power by the auxiliary inverters 43-46 and supplied to the auxiliary motors 47-50. At this time, at least a part of the drive power Q of the auxiliary motors 47 to 50 is provided by regenerative power, so that the load on the engine 20 can be reduced by reducing or stopping the power generation of the auxiliary generator 40.

[0026] The auxiliary inverters 43-46 convert the DC power of the auxiliary circuit 42 into AC power and supply it to the auxiliary motors 47-50. The auxiliary motors 47-50 drive the auxiliary devices such as the cooling fans 80-83. The converter 60 is a step-down device that steps down the DC power of the main circuit 32 and supplies it to the auxiliary circuit 42. The controller 100 controls the engine 20, the main generator 30, the auxiliary generator 40, the travel inverters 33, 34, the auxiliary inverters 43-46, and the converter 60 in response to input signals from an accelerator pedal 70, a brake pedal 71, and a vehicle speed sensor 72.

[0027] The controller 100 has a coasting detection unit 101 that detects the coasting state of the dump truck. The coasting detection unit 101 is a functional block that is realized when a calculation device such as a CPU executes a program stored in a storage device such as a ROM or RAM.

[0028] 3 is a control flow diagram of the electric drive system in this embodiment. The processing of each step will be explained below in order.

[0029] The controller 100 first determines whether the brake pedal 71 is being operated (step S101). If the determination in step S101 is No, the controller 100 controls the traveling inverters 33, 34 to generate regenerative power according to the amount of operation of the brake pedal 71, turns on the chopper 37, and turns on the converter 60 (step S102), and ends the flow. As a result, an electric braking force according to the amount of operation of the brake pedal 71 is generated in the traveling motors 35, 36, and the vehicle body decelerates. Furthermore, most of the regenerative power of the traveling motors 35, 36 is consumed by the thermal resistor 38, and the remaining regenerative power is used to drive the accessory motors 47-50 after being stepped down by the converter 60.

[0030] If the determination in step S101 is Yes, it is then determined whether the accelerator pedal 70 is being operated (step S103). If the determination in step S103 is No, the driving inverters 33, 34 are controlled so that power corresponding to the amount of operation of the accelerator pedal 70 is supplied to the driving motors 35, 36, the converter 60 is turned OFF (step S104), and the flow ends. As a result, the vehicle accelerates according to the amount of operation of the accelerator pedal 70.

[0031] If the determination in step S103 is Yes, it is determined whether the vehicle speed is equal to or greater than a predetermined threshold value F (step S105). If the determination in step S105 is No, the process proceeds to step S104.

[0032] If the determination in step S105 is Yes, the driving inverters 33, 34 are controlled to generate regenerative power, the converter 60 is turned ON (step S106), and the flow ends. The regenerative power referred to here is, for example, regenerative power generated in response to an electric braking force that does not affect coasting, and does not need to be constant. As a result, at least a portion of the drive power Q of the auxiliary motors 47-50 during coasting is provided by regenerative power, so that power generation by the auxiliary generator 40 can be stopped or suppressed.

[0033] (summary) In this embodiment, the system includes an engine 20, a main generator 30 and an auxiliary generator 40 driven by the engine 20, a main rectifier 31 that converts the power generated by the main generator 30 into DC power, an auxiliary rectifier 41 that converts the power generated by the auxiliary generator 40 into DC power, a main circuit 32 to which DC power is supplied from the main rectifier 31, an auxiliary circuit 42 to which DC power is supplied from the auxiliary rectifier 41, travel motors 35 and 36, and a power converter 43 that converts the DC power of the main circuit 32 into AC power. The inverters 33, 34 supply power to the travel motors 35, 36, the auxiliary inverters 43-46 convert DC power from the auxiliary circuit 42 into AC power and supply it to the auxiliary motors 47-50, the converter 60 reduces the DC power from the main circuit 32 and supplies it to the auxiliary circuit 42, the accelerator pedal 70 commands the travel motors 35, 36 to increase speed, the brake pedal 71 commands the travel motors 35, 36 to decrease speed, and the accelerator pedal 70 and the brake pedal 71 and a controller 100 that controls the main generator 30, the auxiliary generator 40, the traveling inverters 33, 34, the auxiliary inverters 43-46, and the converter 60 in response to input signals from the vehicle. The controller 100 controls the traveling inverters 33, 34 so that the traveling motors 35, 36 generate regenerative power when the brake pedal 71 is operated. The controller 100 is provided with a vehicle speed sensor 72 that detects vehicle speed, and detects a state in which neither the accelerator pedal 70 nor the brake pedal 71 is operated and the vehicle speed is equal to or greater than a predetermined threshold value F as a coasting state. When the controller 100 detects the coasting state, it controls the traveling inverters 33, 34 so that the traveling motors 35, 36 generate regenerative power, operates the converter 60, and controls the auxiliary inverters 43-46 so that the regenerative power is supplied to the auxiliary motors 47-50.

[0034] According to the present embodiment configured as described above, regenerative power is generated by the traction motors 35, 36 not only when the brake pedal 71 is operated, but also when the vehicle is coasting with neither the accelerator pedal 70 nor the brake pedal 71 being operated, and this regenerative power can cover at least a portion of the drive power Q of the accessory motors 47 to 50. As a result, power generation by the auxiliary generator 40 is suppressed and the load on the engine 20 is reduced, making it possible to improve fuel efficiency.

[0035] The regenerative power generated during coasting is equivalent to the drive power (several tens of kW) of the auxiliary motors 47-50, and is much smaller than the regenerative power (several thousands of kW) generated when the brake pedal 71 is depressed, so it has almost no effect on the traveling operation. Also, by directly supplying the regenerative power to the auxiliary motors 47-50, the capacity of the storage battery for storing the regenerative power can be reduced. This ensures the loading capacity of the dump truck, allowing productivity to be maintained without reducing transportation efficiency. [Example]

[0036] A second embodiment of the present invention will be described, focusing on the differences from the first embodiment. Fig. 4 is a configuration diagram of an electric drive system in this embodiment. In Fig. 4, a controller 100 further includes an auxiliary power calculation unit 102 that calculates the drive power Q of auxiliary motors 47-50. The drive power Q is calculated by integrating the output power of auxiliary inverters 43-46. Note that, because the drive power Q is approximately equal to the power generated by the auxiliary generator 40, the power generated by the auxiliary generator 40 may be calculated as the drive power Q.

[0037] Fig. 5 is a control flow diagram of the electric drive system in this embodiment. In Fig. 5, the processing of steps S201 to S205 is the same as steps S101 to S105 (shown in Fig. 3) in the first embodiment.

[0038] If it is determined in step S205 that the vehicle speed is equal to or greater than the threshold value F (Yes), the drive power Q of the accessory motors 47-50 is calculated, the traveling inverters 33, 34 are controlled so as to generate regenerative power equivalent to the drive power Q, the converter 60 is turned ON (step S206), and the flow ends. As a result, the drive power Q of the accessory motors 47-50 is supplied only by the regenerative power during coasting, and power generation by the auxiliary generator 40 can be stopped.

[0039] (summary) When the controller 100 in this embodiment detects a coasting state, it calculates the driving power Q of the accessory motors 47 to 50 and controls the driving inverters 33, 34 so that the regenerative power obtained from the traveling motors 35, 36 matches the driving power Q.

[0040] According to this embodiment configured as described above, during coasting, the drive power Q of the auxiliary motors 47 to 50 is supplied only by regenerative power, so that the power generation of the auxiliary generator 40 can be stopped, thereby making it possible to improve the fuel efficiency of the engine 20 more than in the first embodiment. [Example]

[0041] A third embodiment of the present invention will be described below, focusing on the differences from the second embodiment. Fig. 6 is a configuration diagram of an electric drive system in this embodiment. In Fig. 6, the electric drive system further includes a suspension pressure sensor 73 that detects the pressure in the front wheel suspension cylinders 9L, 9R and the rear wheel suspension cylinders 10L, 10R, and the controller 100 further includes a descending inclination angle calculation unit 103 that calculates the descending inclination angle θ of the driving surface.

[0042] Fig. 7 is a control flow diagram of the electric drive system in this embodiment. In Fig. 6, the processing of steps S301 to S305 is the same as steps S201 to S205 (shown in Fig. 5) in the second embodiment.

[0043] If it is determined in step S305 that the vehicle speed is equal to or greater than the threshold value F (Yes), it is determined whether the descending gradient angle θ is equal to or greater than a predetermined threshold value α (for example, 3°) (step S306). The descending gradient angle θ is calculated using the following formula.

[0044]

number

[0045] Here, the front wheel load Wf is determined from the pressure in the front wheel suspension cylinders 9L, 9R, and the front wheel load Wf is determined from the pressure in the rear wheel suspension cylinders 10L, 10R.

[0046] If the determination in step S306 is No, the process of step S304 is executed and the flow ends. As a result, no regenerative power is generated during coasting except on a downhill slope.

[0047] If the determination in step S306 is Yes, the drive power Q of the accessory motors 47-50 is calculated, the travel inverters 33, 34 are controlled to generate regenerative power equivalent to the drive power Q, the converter 60 is turned ON (step S307), and the flow ends. As a result, during coasting on a downhill slope, the drive power Q of the accessory motors 47-50 is covered solely by the regenerative power of the travel motors 35, 36, so power generation by the auxiliary generator 40 can be stopped.

[0048] (summary) The electrically driven vehicle in this embodiment is equipped with a sensor (suspension pressure sensor 73) for detecting the downward slope angle θ of the driving surface, and when the controller 100 detects the coasting state and the downward slope angle θ is less than a predetermined threshold value α, it controls the driving inverters 33, 34 so that no regenerative power is generated, and does not operate the converter 60.

[0049] According to this embodiment configured as described above, when coasting on a slope other than a downhill slope (where deceleration due to running resistance is large), regenerative power is not generated and the running motors 35, 36 do not generate braking force, making it possible to prevent any effect on running operation. Note that, although in this embodiment the downhill inclination angle θ is calculated using the output of the suspension pressure sensor 73, it may also be calculated using the output of an inclination sensor mounted on the vehicle body. [Example]

[0050] A fourth embodiment of the present invention will be described below, focusing on the differences from the third embodiment. Fig. 8 is a configuration diagram of an electric drive system in this embodiment. In Fig. 8, a controller 100 has a load amount calculation unit 104 that calculates the load amount W on the loading platform 3, instead of the descent inclination angle calculation unit 103 (shown in Fig. 6).

[0051] Fig. 9 is a control flow diagram of the electric drive system in this embodiment. In Fig. 7, the processing of steps S401 to S405 is the same as steps S301 to S305 (shown in Fig. 7) in the third embodiment.

[0052] If it is determined in step S405 that the vehicle speed is equal to or greater than the threshold value F (Yes), it is then determined whether the load weight W of the loading platform 3 is equal to or greater than a predetermined threshold value M (e.g., 100 tons) (step S406). The load weight W is calculated by subtracting the total of the front wheel load Wf and the rear wheel load Wr in an unladen state from the total of the front wheel load Wf calculated from the pressure of the front wheel suspension cylinders 9L, 9R and the rear wheel load Wr calculated from the pressure of the rear wheel suspension cylinders 10L, 10R.

[0053] If the determination in step S406 is No, the process of step S404 is executed and the flow ends. As a result, no regenerative power is generated during coasting when the load amount W is large.

[0054] If the determination in step S406 is Yes, the drive power Q of the accessory motors 47-50 is calculated, the travel inverters 33, 34 are controlled to generate regenerative power equivalent to the drive power Q, the converter 60 is turned ON (step S307), and the flow ends. As a result, when coasting with a small load W, the drive power Q of the accessory motors 47-50 is covered solely by the regenerative power of the travel motors 35, 36, so power generation by the auxiliary generator 40 can be stopped.

[0055] (summary) The electrically driven vehicle in this embodiment is equipped with a cargo bed 3 and a sensor (suspension pressure sensor 73) for detecting the load amount on the cargo bed 3, and when the controller 100 detects a coasting state and the load amount W is equal to or greater than a predetermined threshold value M, it controls the driving inverters 33, 34 so that no regenerative power is generated, and does not operate the converter 60.

[0056] According to this embodiment configured as described above, when the vehicle is coasting with a large load weight W (when deceleration due to running resistance is large), no regenerative power is generated and the traveling motors 35, 36 do not generate braking force, making it possible to prevent any influence on the traveling operation. Note that in this embodiment, whether or not to generate regenerative power during coasting is determined based on the load weight W (step S406), but the determination may also be based on the vehicle body mass. [Example]

[0057] A fifth embodiment of the present invention will be described, focusing on the differences from the second embodiment. Fig. 10 is a configuration diagram of an electric drive system in this embodiment. In Fig. 10, a controller 100 has a power generation output detection unit 105 that detects the power generation output of the auxiliary generator 40, instead of the auxiliary power calculation unit 102 (shown in Fig. 4). The power generation output detection unit 105 performs detection based on the output of a sensor that detects the power generation operation of the auxiliary generator 40 (for example, a voltage sensor 74 that detects the power generation voltage of the auxiliary generator 40).

[0058] Fig. 11 is a control flow diagram of the electric drive system in this embodiment. In Fig. 11, the processing of steps S501 to S505 is the same as steps S201 to S205 (shown in Fig. 5) in the second embodiment.

[0059] If it is determined in step S505 that the vehicle speed is equal to or greater than the threshold value F (Yes), it is determined whether the power generation output of the auxiliary generator 40 has been detected (whether the auxiliary generator 40 is generating power) (step S506). If it is determined in step S506 that it is Yes, the traveling inverters 33, 34 are controlled so that the regenerative power of the traveling motors 35, 36 increases slightly (step S507), and the process returns to step S506. This allows the regenerative power of the traveling motors 35, 36 to match the drive power Q of the auxiliary motors 47-50.

[0060] If the determination in step S506 is No, the converter 60 is turned ON (step S609), and the flow ends. As a result, during coasting, the drive power Q of the auxiliary motors 47-50 is provided solely by the regenerative power of the travel motors 35, 36, so power generation by the auxiliary generator 40 can be stopped.

[0061] (summary) The electrically driven vehicle in this embodiment is equipped with a sensor (voltage sensor 74) for detecting the power generation output of the auxiliary generator, and when the controller 100 detects a coasting state, it controls the traveling inverters 33, 34 so that the regenerative power of the traveling motors 35, 36 increases until the power generation output of the auxiliary generator 40 is no longer detected.

[0062] According to this embodiment configured as described above, during coasting, the power generation of the auxiliary generator 40 can be stopped by increasing the regenerative power of the travel motors 35, 36 until the auxiliary generator 40 stops generating power. [Example]

[0063] A sixth embodiment of the present invention will be described below, focusing on the differences from the fifth embodiment. Fig. 12 is a configuration diagram of an electric drive system in this embodiment. In Fig. 12, the electric drive system further includes a suspension pressure sensor 73, and the controller 100 further includes a descending slope angle calculation unit 103.

[0064] Fig. 13 is a control flow diagram of the electric drive system in this embodiment. In Fig. 13, the processing of steps S601 to S605 is the same as steps S501 to S505 (shown in Fig. 11) in the fifth embodiment.

[0065] If it is determined in step S605 that the vehicle speed is equal to or greater than the threshold value F (Yes), it is determined whether the descending gradient angle θ is equal to or greater than the threshold value α (step S606).If it is determined in step S606 that it is Yes, it is determined whether the power generation output of the auxiliary generator 40 has been detected (whether the auxiliary generator 40 is generating power) (step S607).

[0066] If the determination in step S607 is Yes, the travel inverters 33, 34 are controlled so that the regenerative power of the travel motors 35, 36 increases slightly (step S608), and the process returns to step S607. This allows the regenerative power of the travel motors 35, 36 to match the drive power Q of the accessory motors 47-50.

[0067] If the determination in step S607 is No, the converter 60 is turned ON (step S609), and the flow ends. As a result, during coasting, the drive power Q of the auxiliary motors 47-50 is provided solely by the regenerative power of the travel motors 35, 36, so power generation by the auxiliary generator 40 can be stopped.

[0068] (summary) The electrically driven vehicle in this embodiment is equipped with a sensor (voltage sensor 74) for detecting the power generation output of the auxiliary generator 40, and when the controller 100 detects a coasting state and the descending slope angle θ is equal to or greater than a predetermined threshold value α, it controls the traveling inverters 33, 34 so that the regenerative power of the traveling motors 35, 36 increases until the power generation output of the auxiliary generator 40 is no longer detected.

[0069] According to this embodiment configured as described above, when coasting down a slope, the power generation of the auxiliary generator 40 can be stopped by increasing the regenerative power of the travel motors 35, 36 until the auxiliary generator 40 stops generating power.

[0070] The electrically driven vehicle in this embodiment also includes a sensor (suspension pressure sensor 73) for detecting the descending slope angle θ of the driving surface, and when controller 100 detects a coasting state and the descending slope angle θ is less than a predetermined threshold value α, it controls the traveling inverters 33, 34 so that regenerative power is not generated and does not operate converter 60. As a result, when coasting on a slope other than a descending slope (when deceleration due to running resistance is large), regenerative power is not generated and the traveling motors 35, 36 do not generate braking force, preventing any impact on driving operation. [Example]

[0071] A seventh embodiment of the present invention will be described below, focusing on the differences from the fifth embodiment. Fig. 14 is a configuration diagram of an electric drive system in this embodiment. In Fig. 14, the electric drive system further includes a suspension pressure sensor 73, and the controller 100 further includes a cargo amount calculation unit 104.

[0072] Fig. 15 is a control flow diagram of the electric drive system in this embodiment. In Fig. 15, the processing of steps S701 to S705 is the same as steps S501 to S505 (shown in Fig. 11) in the fifth embodiment.

[0073] If it is determined in step S705 that the vehicle speed is equal to or greater than the threshold value F (Yes), it is determined whether or not the cargo amount W is equal to or greater than the threshold value M (step S706).If it is determined in step S706 that it is Yes, it is determined whether or not the power generation output of the auxiliary generator 40 has been detected (whether or not the auxiliary generator 40 is generating power) (step S707).

[0074] If the determination in step S707 is Yes, the travel inverters 33, 34 are controlled so that the regenerative power of the travel motors 35, 36 increases slightly (step S708), and the process returns to step S707. This allows the regenerative power of the travel motors 35, 36 to match the drive power Q of the accessory motors 47-50.

[0075] If the determination in step S707 is No, the converter 60 is turned ON (step S709), and the flow ends. As a result, during coasting, the drive power Q of the auxiliary motors 47-50 is provided solely by the regenerative power of the travel motors 35, 36, so power generation by the auxiliary generator 40 can be stopped.

[0076] (summary) The electrically driven vehicle in this embodiment is equipped with a sensor (voltage sensor 74) for detecting the power generation output of the auxiliary generator 40, and when the controller 100 detects a coasting state and the load amount W is less than a predetermined threshold value M, it controls the traveling inverters 33, 34 so that the regenerative power of the traveling motors 35, 36 increases until the power generation output of the auxiliary generator 40 is no longer detected.

[0077] According to the present embodiment configured as described above, when coasting with a small load amount W, the power generation of the auxiliary generator 40 can be stopped by increasing the regenerative power of the travel motors 35, 36 until the auxiliary generator 40 stops generating power.

[0078] The electrically driven vehicle in this embodiment also includes a loading platform 3 and a sensor (suspension pressure sensor 73) for detecting the load weight W of the loading platform 3, and when the controller 100 detects a coasting state and the load weight W is equal to or greater than a predetermined threshold value M, it controls the traveling inverters 33, 34 so that regenerative power is not generated and does not operate the converter 60. As a result, when coasting with a large load weight W (large deceleration due to running resistance), regenerative power is not generated and the traveling motors 35, 36 do not generate braking force, preventing any impact on the traveling operation. [Example]

[0079] An eighth embodiment of the present invention will be described, focusing on the differences from the third embodiment. FIG. 16 is a configuration diagram of an electric drive system in this embodiment. In FIG. 16, the electric drive system further includes a storage battery 90 and a charge / discharge controller 91 consisting of a bidirectional converter. The storage battery 90 is connected to the auxiliary circuit 42 via the charge / discharge controller 91. The charge / discharge controller 91 charges and discharges the storage battery 90 in response to commands from a controller 100.

[0080] Fig. 17 is a control flow diagram of the electric drive system in this embodiment. In Fig. 17, the processing in steps S801 and S803 to S806 is the same as steps S301 and S303 to S306 (shown in Fig. 6) in the third embodiment.

[0081] If the determination in step S801 is No, the travel inverters 33, 34 are controlled to generate regenerative power according to the amount of operation of the brake pedal 71, the chopper 37 is turned ON, the converter 60 is turned ON, and charging of the storage battery 90 is turned ON (step S802), and the flow ends. As a result, an electric braking force according to the amount of operation of the brake pedal 71 is generated in the travel motors 35, 36, and the vehicle body decelerates. Furthermore, most of the regenerative power of the travel motors 35, 36 is consumed in the thermal resistor 38, and the remaining regenerative power is stepped down by the converter 60 and then used to drive the accessory motors 47-50 and charge the storage battery 90.

[0082] If it is determined in step S806 that the descending gradient angle θ is equal to or greater than the threshold value α (Yes), it is then determined whether the descending gradient angle θ is equal to or greater than the threshold value β (>α) (step S807). If it is determined in step S807 that it is No, the drive power Q of the accessory motors 47-50 is calculated, the travel inverters 33, 34 are controlled so as to generate regenerative power equivalent to the drive power Q, the converter 60 is turned ON, charging of the storage battery 90 is turned OFF (step S808), and the flow ends. As a result, during coasting on a slight downward slope, the drive power Q of the accessory motors 47-50 is supplied solely by regenerative power, and power generation by the auxiliary generator 40 can be stopped.

[0083] If the determination in step S807 is Yes, the travel inverters 33, 34 are controlled to further increase the regenerative power of the travel motors 35, 36, the converter 60 is turned ON, charging of the storage battery 90 is turned ON (step S1111), and the flow ends. As a result, when coasting on a steep downhill slope, part of the regenerative power is used to provide drive power Q for the accessory motors 47-50 and charge the storage battery 90. The power charged in the storage battery 90 is used as drive power for the accessory motors 47-50 when traveling without operating the brake pedal 71. As a result, the power generated by the auxiliary generator 40 is suppressed, thereby reducing the load on the engine 20 that drives the auxiliary generator 40 and improving fuel efficiency.

[0084] (summary) In this embodiment, a sensor (suspension pressure sensor 73) for detecting the descending inclination angle θ of the traveling surface, a storage battery 90, and a charge / discharge controller 91 for supplying and receiving power between the storage battery 90 and the auxiliary circuit 42 are provided. When the controller 100 detects a coasting state and the descending inclination angle θ is equal to or greater than a predetermined first threshold value α and less than a predetermined second threshold value β, the controller 100 controls the traveling inverters 33, 34 so that the regenerative power obtained from the traveling motors 35, 36 matches the drive power Q of the auxiliary motors 47 to 50, and converts the inverters 33, 34 to the converters 34. The inverter 60 is operated to control the auxiliary inverters 43-46 and the charge / discharge controller 91 so that the regenerated power is supplied only to the auxiliary motors 47-50, and when a coasting state is detected and the descending slope angle θ is equal to or greater than the second threshold value β, the inverters 33, 34 are controlled so that the regenerated power is greater than the drive power Q, the converter 60 is operated, and the inverters 43-46 and the charge / discharge controller 91 are controlled so that the regenerated power is supplied only to the auxiliary motors 47-50 and the storage battery 90.

[0085] According to this embodiment configured as described above, when coasting on a small downhill slope (when deceleration due to running resistance is small), the accessory motors 47-50 are driven by regenerative power alone, and when coasting on a large downhill slope (when deceleration due to running resistance is very small), the accessory motors 47-50 can be driven by regenerative power alone and the storage battery 90 can be charged. [Example]

[0086] A ninth embodiment of the present invention will be described below, focusing on the differences from the eighth embodiment. Fig. 18 is a configuration diagram of an electric drive system in this embodiment. In Fig. 18, a controller 100 has a cargo amount calculation unit 104 instead of the descent tilt angle calculation unit 103 (shown in Fig. 16).

[0087] Fig. 19 is a control flow diagram of the electric drive system in this embodiment. In Fig. 19, the processing of steps S901 to S905 is the same as steps S801 to S805 (shown in Fig. 17) in the eighth embodiment.

[0088] If it is determined in step S905 that the vehicle speed is equal to or greater than threshold value F (Yes), it is then determined whether or not load weight W is less than threshold value M (step S906). If it is determined in step S906 that it is No, the drive power Q of the accessory motors 47-50 is calculated, the travel inverters 33, 34 are controlled so as to generate regenerative power equivalent to drive power Q, the converter 60 is turned ON, charging of the storage battery 90 is turned OFF (step S907), and the flow ends. As a result, during coasting with a large load weight W, the drive power Q of the accessory motors 47-50 is supplied solely by the regenerative power of the travel motors 35, 36, so that power generation by the auxiliary generator 40 can be stopped.

[0089] If the determination in step S906 is Yes, the drive power Q of the accessory motors 47-50 is calculated, the drive inverters 33, 34 are controlled so that the regenerative power of the travel motors 35, 36 is greater than the drive power Q of the accessory motors 47-50, the converter 60 is turned ON, charging of the storage battery 90 is turned ON (step S907), and the flow ends. As a result, during coasting with a small load amount W, part of the regenerative power of the travel motors 35, 36 covers the drive power Q of the accessory motors 47-50, and the remaining regenerative power is charged to the storage battery 90.

[0090] (summary) In this embodiment, the vehicle is equipped with a loading platform 3, a sensor (suspension pressure sensor 73) for detecting the load amount on the loading platform 3, and a storage battery 90 connected to the auxiliary circuit 42. When the controller 100 detects a coasting state and the load amount W on the loading platform 3 is equal to or greater than a predetermined threshold M, the controller 100 controls the traveling inverters 33, 34 so that the regenerative power obtained from the traveling motors 35, 36 matches the drive power Q of the auxiliary motors 47-50, operates the converter 60, and controls the auxiliary inverters 43-46 and the charge / discharge controller 91 so that the regenerative power is supplied only to the auxiliary motors 47-50. When the controller 100 detects a coasting state and the load amount W is less than the threshold M, the controller 100 controls the traveling inverters 33, 34 so that the regenerative power is greater than the drive power Q, operates the converter 60, and controls the auxiliary inverters 43-46 and the charge / discharge controller 91 so that the regenerative power is supplied to the auxiliary motors 47-50 and the storage battery 90.

[0091] According to this embodiment configured as described above, when coasting with a large load weight W (when the deceleration due to running resistance is large), the auxiliary motors 47-50 are driven by regenerative power alone, and when coasting with a small load weight W (when the deceleration due to running resistance is small), the auxiliary motors 47-50 can be driven by regenerative power alone and the storage battery 90 can be charged. [Example]

[0092] A tenth embodiment of the present invention will be described below, focusing on the differences from the eighth embodiment. Fig. 20 is a configuration diagram of an electric drive system in this embodiment. In Fig. 20, a controller 100 has a power generation output detection unit 105 instead of the auxiliary power calculation unit 102 (shown in Fig. 16).

[0093] Fig. 21 is a control flow diagram of the electric drive system in this embodiment. In Fig. 21, the processing of steps S1001 to S1006 is the same as steps S801 to S806 (shown in Fig. 17) in the eighth embodiment.

[0094] If it is determined in step S1006 that the descending gradient angle θ is equal to or greater than the threshold value α (Yes), it is determined whether the power generation output of the auxiliary generator 40 has been detected (whether the auxiliary generator 40 is generating power) (step S1007). If it is determined in step S1007 that it is Yes, the traveling inverters 33, 34 are controlled so that the regenerative power of the traveling motors 35, 36 increases slightly (step S1008), and the process returns to step S1007. This allows the regenerative power of the traveling motors 35, 36 to match the drive power Q of the auxiliary motors 47-50.

[0095] If the determination in step S1007 is No, it is determined whether the descending gradient angle θ is equal to or greater than the threshold value β (step S1009). If the determination in step S1009 is No, the converter 60 is turned ON, charging of the storage battery 90 is turned OFF (step S1010), and the flow ends. As a result, during coasting on a small descending gradient, the regenerative power of the travel motors 35, 36 covers the drive power Q of the auxiliary motors 47-50, so power generation by the auxiliary generator 40 can be stopped.

[0096] If the determination in step S1009 is Yes, the travel inverters 33, 34 are controlled to further increase the regenerative power of the travel motors 35, 36, the converter 60 is turned ON, charging of the storage battery 90 is turned ON (step S1011), and the flow ends. As a result, during coasting on a steep downhill slope, the regenerative power of the travel motors 35, 36 covers the drive power Q of the accessory motors 47-50, and the remaining regenerative power is charged to the storage battery 90.

[0097] (summary) In this embodiment, a sensor (suspension pressure sensor 73) for detecting the descending inclination angle θ of the traveling surface, a storage battery 90, and a charge / discharge controller 91 for supplying and receiving power between the storage battery 90 and the auxiliary circuit 42 are provided. When the controller 100 detects a coasting state and the descending inclination angle θ is equal to or greater than a predetermined first threshold value α and less than a predetermined second threshold value β, the controller 100 controls the traveling inverters 33, 34 so that the regenerative power obtained from the traveling motors 35, 36 matches the drive power Q of the auxiliary motors 47 to 50, and converts the inverters 33, 34 to the converters 34. The inverter 60 is operated to control the auxiliary inverters 43-46 and the charge / discharge controller 91 so that the regenerated power is supplied only to the auxiliary motors 47-50, and when a coasting state is detected and the descending slope angle θ is equal to or greater than the second threshold value β, the inverters 33, 34 are controlled so that the regenerated power is greater than the drive power Q, the converter 60 is operated, and the inverters 43-46 and the charge / discharge controller 91 are controlled so that the regenerated power is supplied only to the auxiliary motors 47-50 and the storage battery 90.

[0098] According to this embodiment configured as described above, when coasting on a small downhill slope (when deceleration due to running resistance is small), the accessory motors 47-50 can be driven by regenerative power alone, and when coasting on a large downhill slope (when deceleration due to running resistance is very small), the accessory motors 47-50 can be driven by regenerative power alone and the storage battery 90 can be charged. [Example]

[0099] An eleventh embodiment of the present invention will be described below, focusing on the differences from the tenth embodiment. Fig. 22 is a configuration diagram of an electric drive system in this embodiment. In Fig. 22, a controller 100 has a cargo amount calculation unit 104 instead of the descent tilt angle calculation unit 103 (shown in Fig. 20).

[0100] Fig. 23 is a control flow diagram of the electric drive system in this embodiment. In Fig. 23, the processing of steps S1101 to S1105 is the same as steps S1001 to S1005 (shown in Fig. 21) in the tenth embodiment.

[0101] If it is determined in step S1105 that the vehicle speed is equal to or greater than the threshold value F (Yes), it is then determined whether or not the power generation output of the auxiliary generator 40 has been detected (whether or not the auxiliary generator 40 is generating power) (step S1106). If it is determined in step S1106 that it is Yes, the travel inverters 33, 34 are controlled so that the regenerative power of the travel motors 35, 36 is slightly increased (step S1107), and the process returns to step S1106. This allows the regenerative power of the travel motors 35, 36 to match the drive power Q of the accessory motors 47-50.

[0102] If the result of the determination in step S1106 is No, it is determined whether the load amount W is less than the threshold value M (step S1108). If the result of the determination in step S1108 is No, the converter 60 is turned ON, charging of the storage battery 90 is turned OFF (step S1109), and the flow ends. As a result, when coasting with a large load amount W, the drive power Q of the accessory motors 47-50 is provided only by the regenerative power.

[0103] If the determination in step S1108 is Yes, the travel inverters 33, 34 are controlled to further increase the regenerative power of the travel motors 35, 36, the converter 60 is turned ON, charging of the storage battery 90 is turned ON (step S1110), and the flow ends. As a result, during coasting with a small load amount W, part of the regenerative power is used to cover the drive power Q of the accessory motors 47-50, and the remaining regenerative power is charged to the storage battery 90.

[0104] (summary) In this embodiment, the vehicle is equipped with a loading platform 3, a sensor (suspension pressure sensor 73) for detecting the load weight W of the loading platform 3, and a storage battery 90 connected to the auxiliary circuit 42. When the controller 100 detects a coasting state and the load weight W is equal to or greater than a predetermined threshold value M, it controls the traveling inverters 33, 34 so that the regenerative power obtained from the traveling motors 35, 36 matches the drive power Q of the auxiliary motors 47-50, operates the converter 60, and controls the auxiliary inverters 43-46 and the charge / discharge controller 91 so that the regenerative power is supplied only to the auxiliary motors 47-50. When the controller 100 detects a coasting state and the load weight W is less than the threshold value M, it controls the traveling inverters 33, 34 so that the regenerative power is greater than the drive power Q, operates the converter 60, and controls the auxiliary inverters 43-46 and the charge / discharge controller 91 so that the regenerative power is supplied to the auxiliary motors 47-50 and the storage battery 90.

[0105] According to this embodiment configured as described above, when coasting with a large load weight W (when the deceleration due to running resistance is large), the auxiliary motors 47-50 are driven by regenerative power alone, and when coasting with a small load weight W (when the deceleration due to running resistance is small), the auxiliary motors 47-50 can be driven by regenerative power alone and the storage battery 90 can be charged.

[0106] Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments and includes various modifications. For example, the above-described embodiments have been described in detail to clearly explain the present invention, and the present invention is not necessarily limited to those including all of the described configurations. Furthermore, it is possible to add part of the configuration of one embodiment to the configuration of another embodiment, or to delete part of the configuration of one embodiment or replace it with part of another embodiment. [Explanation of symbols]

[0107] 1...body frame, 2...load, 3...loading platform, 4...hoist cylinder, 5...hinge pin, 6L, 6R...front wheels, 7L, 7R...rear wheels, 9L, 9R...front wheel suspension cylinder, 10L, 10R...rear wheel suspension cylinder, 11...deck, 12...cab, 13...control cabinet, 14...grid box, 15...power unit, 20...engine, 30...main generator, 31...main rectifier, 32...main circuit, 33, 34...travel inverter, 35, 36...travel motor, 37...chopper, 38...thermal resistor resistor, 40...auxiliary generator, 41...auxiliary rectifier, 42...auxiliary circuit, 43-46...auxiliary inverter, 47-50...auxiliary motor, 60...converter, 70...accelerator pedal, 71...brake pedal, 72...vehicle speed sensor, 73...suspension pressure sensor, 74...voltage sensor, 80-83...cooling fan, 90...storage battery, 91...charge / discharge controller, 100...controller, 101...coasting detection unit, 102...auxiliary power calculation unit, 103...descent slope angle calculation unit, 104...load amount calculation unit, 105...power generation output detection unit.

Claims

1. The engine and a main generator and an auxiliary generator driven by the engine; a main rectifier that converts the power generated by the main generator into DC power; an auxiliary rectifier that converts the power generated by the auxiliary generator into DC power; a main circuit supplied with DC power from the main rectifier; an auxiliary circuit to which DC power is supplied from the auxiliary rectifier; A traction motor; a driving inverter that converts DC power of the main circuit into AC power and supplies the AC power to the driving motor; an accessory motor; an auxiliary inverter that converts DC power of the auxiliary circuit into AC power and supplies the AC power to the auxiliary motor; a converter that reduces the DC power of the main circuit and supplies the reduced DC power to the auxiliary circuit; an accelerator pedal for instructing the travel motor to increase its speed; a brake pedal for instructing the driving motor to decelerate; a controller that controls the main generator, the auxiliary generator, the driving inverter, the auxiliary inverter, and the converter in response to input signals from the accelerator pedal and the brake pedal, In an electrically driven vehicle, the controller controls the traveling inverter so that the traveling motor generates regenerative power when the brake pedal is operated, Equipped with a vehicle speed sensor that detects vehicle speed, The controller a state in which neither the accelerator pedal nor the brake pedal is operated and the vehicle speed is equal to or greater than a predetermined threshold is detected as a coasting state; When the coasting state is detected, the inverter for driving is controlled so that the driving motor generates regenerative power, the converter is operated, and the regenerative power is supplied to the motor for auxiliary equipment; A drive power of the auxiliary motor is calculated, and the traction inverter is controlled so that the regenerative power matches the drive power. An electrically driven vehicle.

2. 2. The electrically driven vehicle according to claim 1, a sensor for detecting the power generation output of the auxiliary generator; When the controller detects the coasting state, the controller controls the traveling inverter so that the regenerative power of the traveling motor increases until the power generation output of the auxiliary generator is no longer detected. An electrically driven vehicle.

3. 2. The electrically driven vehicle according to claim 1, A sensor is provided for detecting the downward slope angle of the running surface, When the controller detects the coasting state and the descending slope angle is less than a predetermined threshold, the controller controls the traveling inverter so that the regenerative power is not generated and does not operate the converter. An electrically driven vehicle.

4. 2. The electrically driven vehicle according to claim 1, The loading platform and a sensor for detecting the amount of cargo on the loading platform; When the controller detects the coasting state and the load amount is equal to or greater than a predetermined threshold, the controller controls the traveling inverter so that the regenerative power is not generated and does not operate the converter. An electrically driven vehicle.

5. 2. The electrically driven vehicle according to claim 1, a sensor for detecting a downward inclination angle of a running surface; A storage battery and a charge / discharge controller that supplies and receives electric power between the storage battery and the auxiliary circuit; The controller when the coasting state is detected and the descending slope angle is equal to or greater than a predetermined first threshold value and less than a predetermined second threshold value, the driving inverter is controlled so that the regenerative power matches the drive power of the auxiliary motor, the converter is operated, and the auxiliary inverter and the charge / discharge controller are controlled so that the regenerative power is supplied only to the auxiliary motor; When the coasting state is detected and the descending slope angle is equal to or greater than the second threshold, the drive inverter is controlled so that the regenerative power is greater than the drive power, the converter is operated, and the auxiliary inverter and the charge / discharge controller are controlled so that the regenerative power is supplied to the auxiliary motor and the storage battery. An electrically driven vehicle.

6. 2. The electrically driven vehicle according to claim 1, The loading platform and a sensor for detecting the amount of cargo on the loading platform; A storage battery and a charge / discharge controller that supplies and receives electric power between the storage battery and the auxiliary circuit; The controller When the coasting state is detected and the load amount is equal to or greater than a predetermined threshold, the driving inverter is controlled so that the regenerative power matches the drive power of the auxiliary motor, the converter is operated, and the regenerative power is supplied only to the auxiliary motor; When the coasting state is detected and the load amount is less than the threshold, the drive inverter is controlled so that the regenerative power is greater than the drive power, the converter is operated, and the auxiliary inverter and the charge / discharge controller are controlled so that the regenerative power is supplied to the auxiliary motor and the storage battery. An electrically driven vehicle.

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