JP2012070554A - Riding type lawn mowing vehicle and control method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a riding type lawn mowing vehicle which can miniaturize a resistor for regeneration and effectively use energy by properly charge regenerative electric power generated by the motor to a battery, and to provide its control method.SOLUTION: The riding type lawn mowing vehicle 1 includes: a battery B which supplies power; a motor 41 which generates driving force for running by power from the battery B; a speed sensor 36 which detects speed of the vehicle; a 3D gyro sensor 37 which detects an attitude of the vehicle; a regenerative electric power amount estimation part 38b which estimates electric power amount of regenerative electric power generated by the motor 41 based on detection results of the speed sensor 36 and the 3D gyro sensor 37; and a charging control device 38b which controls charging amount of the battery B according to an estimation result of a regenerative electric power amount estimation part 38a.

Description

  The present invention relates to a riding lawnmower vehicle that allows an operator to ride and drive a lawn while mowing and driving, and a control method therefor.

  Riding lawn mower vehicles are equipped with a vehicle body with wheels attached and a lawn mowing unit (reel) that can be raised and lowered provided on the vehicle body. Is possible. For this reason, the riding lawn mowing vehicle cuts grass in a wider area such as a green field or a stadium than a push-type (walk-behind type) lawn mowing vehicle operated by an operator from the rear side of the vehicle. Suitable for

Conventional riding lawn mowing vehicles include an internal combustion engine such as a gasoline engine as a power generation source, and wheels and hydraulic cylinders (hydraulic pressure for raising and lowering the lawn mowing unit using hydraulic power generated by driving a hydraulic pump. Many of them drive cylinders). However, in recent years, in order to reduce the emission of carbon dioxide (CO ₂ ), which is a kind of greenhouse gas, the power of the engine is generated and the storage battery is charged to drive (elevate and lower) the traveling unit and lawn mowing unit. Motorized hybrid type lawn mowers that use motors, and electric motors that drive the driving unit and lawn mower units (including raising and lowering) using electric power supplied from a large-capacity storage battery without the engine. Research and development of passenger-type lawn mowing vehicles is actively underway.

  Since the motor provided in such a riding lawn mower vehicle not only operates as a drive source but also operates as a generator, regenerative power is generated by the motor when the vehicle is decelerated. The regenerative power generated by the motor is consumed by, for example, a regenerative resistor provided to consume the regenerative power, or used for charging a secondary battery (battery) that supplies power for driving the motor. The following Patent Document 1 discloses an example of an electric ground work vehicle in which left and right wheels are independently driven by left and right axle-side electric motors.

JP 2009-255840 A

  By the way, when the regenerative power generated by the motor is consumed by the regenerative resistor, the following problems can be considered. In other words, if the regenerative power generated by the motor is consumed by the regenerative resistor, the regenerative resistor generates heat. Therefore, to install a regenerative resistor in a riding lawn mower vehicle, a resistor with a large power capacity is required. There is a problem that a certain amount of space is required from the viewpoint of preventing temperature rise. In addition, the regenerative power generated by the motor is merely wasted, and there is a problem that the effective use of energy is not achieved.

  In the case of charging a battery using regenerative power generated by a motor, the following problems can be considered although energy is effectively used. In other words, the amount of regenerative electric power of the motor varies greatly depending on the traveling speed of the vehicle, the condition of the traveling path (for example, whether it is downhill, uphill, or flat), so the battery may be overcharged. There is. Further, when the battery is in an overcharged state and the regenerative power generated by the motor cannot be consumed, there is a possibility that the voltage rises and an abnormality such as stopping of the electric device occurs.

  The present invention has been made in view of the above circumstances, and it is possible to reduce the size of a regenerative resistor and effectively use energy by performing control to appropriately charge a battery with regenerative power generated by a motor. An object of the present invention is to provide a riding lawn mowing vehicle that can be used and a control method thereof.

In order to solve the above-described problems, a riding lawn mowing vehicle according to the present invention includes a battery (B) that supplies electric power and a motor (41) that generates a driving force for traveling by the electric power from the battery. Based on the detection results of the first sensor (36) for detecting the speed of the vehicle, the second sensor (37) for detecting the attitude of the vehicle, and the first and second sensors in the type lawn mowing vehicle (1). An estimation unit (38a) that estimates the amount of regenerative power generated by the motor, and a control unit (38b) that controls the amount of charge of the battery according to an estimation result of the estimation unit. Yes.
In the riding lawn mower vehicle of the present invention, the estimation unit obtains the inertial energy of the vehicle according to the detection result of the first sensor, and provides the gradient resistance to the vehicle according to the detection result of the second sensor. The amount of regenerative power generated by the motor is estimated using the inertia energy and the gradient resistance.
In the riding lawn mower vehicle according to the present invention, the estimating unit may calculate the relationship between the first table (T1) indicating the relationship between the vehicle speed and the vehicle inertia energy, and the vehicle attitude and the gradient resistance with respect to the vehicle. A second table (T2), the inertial energy of the vehicle corresponding to the detection result of the first sensor is obtained using the first table, and the second table is used to obtain the inertial energy of the second sensor. It is characterized in that the gradient resistance for the vehicle according to the detection result is obtained.
In the riding lawn mower vehicle of the present invention, the control unit controls the amount of charge of the battery so that the state of charge of the battery does not exceed a preset target charge state.
The riding lawn mowing vehicle of the present invention is configured by applying a mechanical force to the first braking device that applies braking by collecting the regenerative electric power generated by the motor in the battery and the wheels provided in the vehicle. A second braking device that applies braking, and the control unit adjusts the braking amount of the first and second braking devices according to the amount of regenerative power estimated by the estimation unit. To control the amount of charge of the battery.
A method for controlling a riding lawn mowing vehicle according to the present invention includes a battery (B) that supplies electric power and a motor (41) that generates a driving force for traveling by the electric power from the battery ( The control method of 1) is based on the first step (S11) for detecting the speed of the vehicle, the second step (S12) for detecting the attitude of the vehicle, and the detection results of the first and second steps. And a third step (S13) for estimating the amount of regenerative power generated by the motor, and a fourth step (S14) for controlling the charge amount of the battery according to the estimation result of the third step. It is characterized by.

  According to the present invention, the speed and attitude of the vehicle are detected, the amount of regenerative power generated by the motor is estimated based on the detection results, and the charge amount of the battery is controlled according to the estimation results. Therefore, it is possible to perform appropriate charging control of the battery using the regenerative power generated by the motor. As a result, the regenerative resistor can be downsized or the regenerative resistor can be made unnecessary, and the energy can be reduced. There is an effect that it can be used effectively.

1 is a perspective view showing an external appearance of a riding lawn mowing vehicle according to an embodiment of the present invention. It is a block diagram which shows the principal part structure of the control system of the riding type lawn mower vehicle by one Embodiment of this invention. It is a figure for demonstrating the process which estimates the electric energy of the regenerative electric power performed with the riding-type lawn mower vehicle by one Embodiment of this invention. It is a figure for demonstrating charge control of the battery B performed with the riding-type lawn mower vehicle by one Embodiment of this invention. It is a flowchart which shows the control method of the riding-type lawn mower vehicle by one Embodiment of this invention.

  Hereinafter, a riding lawnmower vehicle and a control method thereof according to an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a perspective view showing an appearance of a riding lawn mower according to an embodiment of the present invention. As shown in FIG. 1, the riding lawn mowing vehicle 1 of the present embodiment includes two front wheels 11a and 11b and one rear wheel 12 supported by a frame 10, two front lawn mowing units 13a and 13b, and one The rear lawn mowing unit 14 is provided, and the front lawn mowing units 13a and 13b and the rear lawn mowing unit 14 cut the lawn along the traveling path while traveling by the front wheels 11a and 11b and the rear wheel 12. .

  A riding-type lawn mowing vehicle 1 shown in FIG. 1 is an electric riding-type lawn mowing vehicle that travels using power generated by a motor and cuts grass using power generated by the motor. Note that each of the front lawn mowing units 13a and 13b and the rear lawn mowing unit 14 provided in the riding type lawn mower vehicle 1 is provided with a bucket for accommodating the cut lawn (mowing lawn). The figure which has been removed is shown.

  A seat 15 on which an operator is seated is disposed substantially at the upper center of the frame 10. A steering wheel 16 is provided at the upper front portion of the seat 15, and a reverse accelerator pedal 17, a forward accelerator pedal 18, and a brake pedal 19 are provided at the lower front portion. By operating the steering wheel 16 by an operator seated on the seat 15, the traveling direction of the riding lawn mowing vehicle 1 is determined, and the reverse accelerator pedal 17, the forward accelerator pedal 18, and the brake pedal 19 are operated. The reverse, forward, stop and travel speed of the riding lawn mowing vehicle 1 are determined.

  The front wheels 11a and 11b are respectively disposed on the right front lower portion and the left front lower portion of the frame 10, and are drive wheels driven by power generated by a motor 41 (not shown in FIG. 1, see FIG. 2). It is supported by the frame 10 so as to be rotatable around a rotation axis along the left-right direction of the vehicle. The rear wheel 12 is disposed at the lower center rear portion of the frame 10 and is configured to be swingable in the left-right direction in accordance with the rotation amount of the steering wheel 16 and functions as a steering wheel. As the rear wheel 12 swings in the left-right direction, the rotating shaft of the rear wheel 12 also swings. Therefore, the traveling direction of the riding lawn mowing vehicle 1 is changed by rotating the steering wheel 16.

  Here, for the front wheels 11a and 11b and the rear wheel 12, wide tires having curved shoulders are used. This is to avoid turf damage by dispersing the weight and stress of the lawn mowing vehicle 1 on the front wheels 11a, 11b and the rear wheel 12. Further, tires without grooves are used for the front wheels 11a and 11b and the rear wheel 12. This is to reduce the burden on the turf by increasing the ground contact area as much as possible to disperse the vehicle weight and reduce the resistance.

  The front lawn mowing units 13a and 13b are supported so as to be movable up and down in front of each of the front wheels 11a and 11b, and move down to cut the lawn while in contact with the ground in front of the front wheels 11a and 11b. Each of these front lawn mowing units 13 a and 13 b includes a front roller 21, an electric reel 22 (rotary blade), a rear roller (not shown), and a motor 24. The front roller 21 is a substantially cylindrical member having a rotation axis set in the left-right direction of the vehicle and a plurality of grooves along the circumferential direction formed in the axial direction, and is disposed in front of the electric reel 22. The front roller 21 is provided to support the front lawn mowing units 13a and 13b in a lowered state on the ground.

  The electric reel 22 is a substantially cylindrical member in which a plurality of spiral blades for mowing the lawn are formed on the side surface, the rotation axis is set in the left-right direction of the vehicle, and is driven by the motor 24. The electric reel 22 is disposed between the front roller 21 and a rear roller (not shown), and is disposed above the front roller 21 and the rear roller (not shown) by the height of the grass after cutting. Has been. The height position of the electric reel 22 relative to the front roller 21 and the rear roller (not shown) can be finely adjusted within a range of, for example, about several mm to several tens of mm. The rear roller (not shown) is a substantially cylindrical member that is not formed with a groove like the front roller 21, and, like the front roller 21 described above, the front lawn mowing units 13 a and 13 b that are in the lowered state are provided. It is provided for supporting on the ground.

  A support arm 25a extending in the right direction from the central portion and a support arm 25b extending in the left direction from the central portion are provided at the front portion of the frame 10. The support arm 25a supports the front lawn mowing unit 13a so as to be swingable around the rotation axis in the front-rear direction of the vehicle at the right end thereof, and the support arm 25b rotates at the left end of the rotation axis in the front-rear direction of the vehicle. The front lawn mowing unit 13b is supported so as to be swingable. For this reason, even if the ground is inclined in the left-right direction of the vehicle, the front lawn mowing units 13a and 13b can be inclined in accordance with the inclination.

  Electric cylinders 26a and 26b as electric actuators are attached to the support arms 25a and 25b. When the electric cylinder 26a expands and contracts, the right end of the support arm 25a moves up and down, and the front lawn mowing unit 13a moves up and down. Similarly, when the electric cylinder 26b expands and contracts, the left end portion of the support arm 25b moves in the vertical direction, whereby the front lawn mowing unit 13b moves up and down. That is, the support arms 25a and 25b and the electric cylinders 26a and 26b constitute an elevating mechanism that elevates and lowers the front lawn mowing units 13a and 13b. In FIG. 1, the front lawn mowing unit 13a is raised, and the front lawn mowing unit 13b is lowered.

  The rear lawn mowing unit 14 is supported between the front wheels 11a and 11b and the rear wheel 12 so as to be able to move up and down, and cuts the lawn while being lowered and in contact with the ground in front of the rear wheel 12. Similar to the front lawn mowing units 13a and 13b, the rear lawn mowing unit 14 includes a front roller 21, an electric reel 22 (rotary blade), a rear roller (not shown), and a motor 24, and an electric cylinder 26a. , 26b is lifted and lowered by a lifting mechanism (not shown) including an electric cylinder (electric actuator) and the like. As with the front lawn mowing units 13a and 13b, the rear lawn mowing unit 14 is also supported so as to be able to swing around a rotation axis in the front-rear direction of the vehicle, and matches the inclination of the ground in the left-right direction of the vehicle. Can be tilted.

  Further, a touch panel display device (for example, a liquid crystal display device) 27 is provided in front of the right side of the seat 15 (on the right side of the steering wheel 16). This display device 27 is for inputting various instructions such as information indicating the current state of the riding lawn mowing vehicle 1 as well as inputting instructions from the operator. The raising / lowering of the front lawn mowing units 13a, 13b and the rear lawn mowing unit 14 and the starting / stopping of the electric reels 22 provided thereto are in accordance with instructions input by the operator operating the display device 27. Be controlled. The information displayed on the display device 27 includes the traveling speed of the riding lawn mowing vehicle 1, the rotational speed of the electric reels 22 provided in each of the front lawn mowing units 13a and 13b and the rear lawn mowing unit 14, and the lawn. It is information such as information indicating the development status of the child.

  An illumination device 28 that illuminates the front of the riding lawnmower vehicle 1 is provided below the steering wheel 16 and between the forward accelerator pedal 18 and the brake pedal 19. Further, a battery B for supplying electric power for operating the riding lawn mower 1 is provided on the frame 10 behind the seat 15. Specifically, the electric power supplied from the battery B includes a motor 41 (see FIG. 2) that drives the front wheels 11a and 11b, and a motor 42 (built in an electric cylinder 45 that generates a driving force that swings the rear wheels 12. 2), motors 24a, 43b (see FIG. 2) for generating power for driving the motor 24 and the electric cylinders 26a, 26b provided in the front lawn mowing units 13a, 13b and the rear lawn mowing unit 14, respectively. Used to drive the etc.

  FIG. 2 is a block diagram showing a main configuration of the control system of the riding lawn mower vehicle according to one embodiment of the present invention. In FIG. 2, components corresponding to those shown in FIG. As shown in FIG. 2, the riding lawn mowing vehicle 1 includes a DC / DC converter 31, an AC motor driver 32, an electric cylinder driver 33, electric cylinder drivers 34a and 34b, AC motor drivers 35a and 35b, a speed sensor 36 ( 1st sensor), 3D gyro sensor 37 (2nd sensor), and the control apparatus 38 are provided. In FIG. 2, a path through which power is transmitted is indicated by a solid line, and a signal path related to the control system is indicated by a broken line.

  The DC / DC converter 31 is provided between the battery B and various drivers (AC motor driver 32 to AC motor driver 35b), and is supplied with DC power from the battery B to various drivers under the control of the control device 38. Voltage conversion of the regenerative electric power generated by the motor 41 that drives the front wheels 11a and 11b and recovered by the battery B is performed. Specifically, the output voltage of the battery B is boosted and applied to various drivers, or the electromotive force generated by the motor 41 is stepped down and applied to the battery B.

  The AC motor driver 32 uses direct current power supplied from the battery B via the DC / DC converter 31 and drives a motor 41 that generates power for driving the front wheels 11 a and 11 b under the control of the control device 38. . In FIG. 2, a block (a block denoted by reference numeral 44) provided between the motor 41 and the front wheels 11 a and 11 b reduces the rotational speed of the power (rotational power) generated by the motor 41. The reduction gear (reduction gear) transmitted to the front wheels 11a and 11b is shown.

  Here, the motor 41 not only operates as a power generation source (electric motor) that generates power for driving the front wheels 11a and 11b, but also operates as a generator. Therefore, for example, when the operator operates the forward accelerator pedal 18 or the reverse accelerator pedal 17 to output a signal indicating forward or reverse from the control device 38, the AC motor driver 32 receives the DC / DC from the battery B. The motor 41 is operated as an electric motor using the DC power supplied via the DC converter 31, and the motor 41 is driven forward or backward.

  On the other hand, for example, when a signal indicating deceleration is output from the control device 38 by the operator operating the brake pedal 19, the AC motor driver 32 operates the motor 41 as a generator, and the motor 41 The generated regenerative power is recovered by the battery B via the DC / DC converter 31. When the motor 41 operates as a generator and the regenerative power generated by the motor 41 is collected by the battery B, a regenerative brake (first braking device) that applies braking by the rotational resistance of the motor 41 is realized.

  Although not shown in the figure, the mechanical lawn (second brake) is applied to the riding lawn mowing vehicle 1 by applying mechanical force to the front wheels 11a and 11b such as a disc brake and a drum brake. A braking device) is also provided. Although details will be described later, control for adjusting the braking amount by the regenerative brake and the braking amount by the mechanical brake is performed by the control device 38 in accordance with the amount of regenerative power estimated to be obtained by the motor 41.

  Further, the motor 41 is provided with an encoder or resolver (not shown) that detects the rotation speed of the motor 41, and a rotation speed signal S <b> 1 that indicates a detection result of the encoder or the like is input to the AC motor driver 32. . The AC motor driver 32 communicates with the control device 38, such as the rotational speed of the motor 41 indicated by the rotational speed signal S1, the current flowing through the motor 41, the torque generated in the motor 41, and the like. Send information.

  The electric cylinder driver 33 uses direct-current power supplied from the battery B via the DC / DC converter 31 to drive power for driving the electric cylinder 45 that swings the rear wheel 12 under the control of the control device 38. The generated motor 42 is driven. The motor 42 is provided with an encoder (not shown) for detecting the drive amount of the electric cylinder 45 (that is, the swing angle of the rear wheel 12), and a swing angle signal S2 indicating the detection result of the encoder is provided. This is input to the electric cylinder driver 33. The electric cylinder driver 33 communicates with the control device 38 to transmit information such as the swing angle of the rear wheel 12 indicated by the swing angle signal S2.

  The electric cylinder drivers 34a and 34b use direct current power supplied from the battery B via the DC / DC converter 31 and are motors that generate power for driving the electric cylinders 26a and 26b under the control of the control device 38. 43a and 43b are driven. The AC motor drivers 35a and 35b use DC power supplied from the battery B via the DC / DC converter 31 and are controlled by the control device 38, and the front lawn mowing units 13a and 13b and the rear lawn mowing unit 14 are used. The motor 24 provided in is driven.

  Here, each of the motors 24 provided in the front lawn mowing units 13a and 13b and the rear lawn mowing unit 14 is provided with an encoder or a resolver (not shown) for detecting the respective rotation speeds. The rotation speed signals S3 and S4 indicating the detection results are input to the AC motor drivers 35a and 35b, respectively. 2, the AC motor driver 35a includes a driver for driving the motor 24 provided in the front lawn mowing unit 13a and a driver for driving the motor 24 provided in the front lawn mowing unit 13b. Is included. The rotation speed signal S3 is a signal including a signal indicating the rotation speed of the motor 24 provided in the front lawn mowing unit 13a and a signal indicating the rotation speed of the motor 24 provided in the front lawn mowing unit 13b.

  The speed sensor 36 is a sensor that detects the vehicle speed of the riding lawn mower vehicle 1. The speed sensor 36 is generated, for example, by rotation of a detection gear (gear) having several tens to hundreds of teeth attached to a drive shaft (shaft) between the reduction gear 44 and the front wheels 11a and 11b. It is a sensor that counts pulses at regular intervals and detects the vehicle speed of the riding lawn mowing vehicle 1 from the count result. A sensor that detects the vehicle speed from the pulse interval (interval time) may be used.

  The 3D gyro sensor 37 is a sensor that detects the posture of the riding lawnmower vehicle 1. Specifically, a rotation angle (θX, θY) around two axes (X axis, Y axis) perpendicular to each other in the horizontal plane and a rotation angle around a vertical axis (Z axis) orthogonal to the horizontal plane (Z axis) θZ), and a sensor that detects the acceleration of each of the X, Y, and Z axes. For this reason, acceleration / deceleration of the vehicle speed and ascending / descending of the slope can be determined. Here, an example in which the 3D gyro sensor 37 is used to detect the attitude of the riding lawn mower vehicle 1 will be described. However, instead of the 3D gyro sensor 37, only the inclination in the front-rear direction of the riding lawn mower vehicle 1 is detected. It is also possible to use a sensor. The detection results of the speed sensor 36 and the 3D gyro sensor 37 are output to the control device 38.

  The control device 38 controls the riding lawn mowing vehicle 1 in an integrated manner. For example, the state of charge (SOC) of the battery B is monitored, the power consumption by the DC / DC converter 31 is controlled, and transmitted from various drivers (AC motor driver 32 to AC motor driver 35b). With reference to the signals, the drive amounts of various motors (motors 24, 41 to 43b) are controlled by various drivers.

  The control device 38 includes a regenerative power amount estimation unit 38 a (estimation unit) and a charge control unit 38 b (control unit), and performs charge control of the battery B using the regenerative power generated by the motor 41. The regenerative power amount estimation unit 38 a estimates the amount of regenerative power generated by the motor 41 based on the detection results of the speed sensor 36 and the 3D gyro sensor 37. Specifically, the inertial energy of the riding lawn mowing vehicle 1 according to the detection result of the speed sensor 36 and the gradient resistance with respect to the riding lawn mowing vehicle 1 according to the detection result of the 3D gyro sensor 37 are obtained. It is used to estimate the amount of regenerative power generated by the motor 41.

  FIG. 3 is a diagram for explaining processing for estimating the amount of regenerative power performed in the riding lawn mower vehicle according to the embodiment of the present invention. As shown in FIG. 3, the regenerative power amount estimation unit 38 a includes a table T <b> 1 (first table) indicating the relationship between the speed and inertial energy of the riding lawn mowing vehicle 1, and a gradient (front-rear direction of the riding lawn mowing vehicle 1). And a table T2 (second table) showing the relationship between the gradient resistance with respect to the riding lawn mowing vehicle 1.

  In general, the kinetic energy of an object is proportional to the product of the mass of the object and the square of the velocity of the object. Assuming that the mass of the riding lawn mowing vehicle 1 is constant (for example, 800 kg), the table T1 shows that the inertial energy of the riding lawn mowing vehicle 1 is proportional to the square of the vehicle speed, as shown in FIG. It will be a thing. If the mass of the riding lawn mowing vehicle 1 is constant (for example, 800 kg), the table T2 adds SIN (gradient angle) to the weight of the riding mower 1 as shown in FIG. It will be multiplied. In other words, when the weight of the riding lawn mowing vehicle 1 is W and the gradient is θ, the gradient resistance Re is expressed by the equation Re = W · sin θ.

  The regenerative power amount estimation unit 38a obtains the inertial energy of the riding lawn mowing vehicle 1 according to the detection result of the speed sensor 36 using the table T1 shown in FIG. 3, and the detection result of the 3D gyro sensor 37 using the table T2. The gradient resistance with respect to the riding-type lawn mowing vehicle 1 corresponding to is determined. For example, when the vehicle speed of the riding lawn mowing vehicle 1 detected by the speed sensor 36 is 10 [km / h], the inertia energy of the riding lawn mowing vehicle 1 from the table T1 shown in FIG. 5 [kJ] is obtained. For example, when the gradient detected by the 3D gyro sensor 37 (the posture of the riding lawn mowing vehicle 1 in the front-rear direction) is 30 degrees, the table T2 shown in FIG. About 400 [kg] is determined as the gradient resistance.

  Further, the regenerative electric energy estimating unit 38a includes calculation means 51 to 54 shown in FIG. 3, and the motor 41 performs various calculations on the inertia energy and gradient resistance obtained using the tables T1 and T2. Estimate the amount of regenerative power generated. Note that the computing means 51 to 54 may be realized by hardware such as a logic circuit, or may be realized by software.

  The computing means 51 attaches a positive sign to the gradient resistance obtained using the table T2 when the gradient angle detected by the 3D gyro sensor 37 is a depression angle (downward angle), and the elevation angle (upward direction). In the case of the angle), a calculation with a negative sign is performed. The calculation means 52 performs a calculation for multiplying the calculation result of the calculation means 51 by a preset coefficient (k1). The calculating means 53 performs an operation of multiplying the inertia energy obtained using the table T1 by the calculation result of the calculating means 52. Further, the calculation means 54 performs a calculation to multiply the calculation result of the calculation means 53 by a preset coefficient (k2). By performing such calculation, the amount of regenerative power is estimated.

  The charge control unit 38b controls the charge amount of the battery B according to the estimation result of the regenerative power amount estimation unit 38a. However, the charge amount of the battery B is controlled so that the charge state of the battery B does not exceed a preset target charge state. FIG. 4 is a diagram for explaining the charging control of the battery B performed in the riding lawn mower vehicle according to the embodiment of the present invention. In FIG. 4, the horizontal axis represents the amount of regenerative power estimated by the regenerative power amount estimation unit 38b, and the vertical axis represents the state of charge (SOC) of the battery B. However, to facilitate understanding, the amount of regenerative power taken along the horizontal axis is expressed as a percentage of the amount of power that can be charged by the battery B. It is assumed that the target charge state of battery B is set to 70%.

  The charge control unit 38b has a relationship between the current state of charge of the battery B and the regenerative power amount estimated by the regenerative power amount estimation unit 38a in a region (region not hatched) marked with a symbol R1. If the relationship is included, control is performed to apply braking only by regenerative braking without using mechanical braking. On the other hand, when the same relationship is included in the region indicated by the symbol R2 in the drawing (the region indicated by hatching), control is performed to apply braking using a mechanical brake in addition to the regenerative braking. .

  For example, the current charge state of the battery B is 59%, and the amount of regenerative power estimated by the regenerative power amount estimation unit 38a is the amount of power corresponding to 10% of the total capacity of the battery B. Consider the case where the relationship between the current state of charging and the amount of regenerative power estimated by the regenerative power amount estimating unit 38a is included in the region R1 in FIG. In such a case, even if all the regenerative electric power estimated to be generated by the motor 41 is charged to the battery B, the charged state of the battery B does not exceed 70% that is the target charged state. For this reason, the charging control unit 38b performs control to apply braking only with the regenerative brake without using the mechanical brake so that the battery B can collect all the regenerative power generated by the motor 41.

  On the other hand, for example, the current charge state of the battery B is 59%, and the amount of regenerative power estimated by the regenerative power amount estimation unit 38a is the amount of power corresponding to 20% of the total capacity of the battery B. A case is considered in which the relationship between the current state of charge of the battery B and the regenerative power amount estimated by the regenerative power amount estimation unit 38a is included in the region R2 in FIG. In such a case, if all of the regenerative electric power estimated to be generated by the motor 41 is charged in the battery B, the state of charge of the battery B exceeds the target charge state of 70%.

  For this reason, the charging control unit 38b performs control to apply braking using the mechanical brake in addition to the regenerative braking so that the charging state of the battery B does not exceed the target charging state. Specifically, among the electric energy estimated by the regenerative electric energy estimating unit 38a (the electric energy corresponding to 20% of the total capacity of the battery B), the target charging state is 70% and the current charging state is 59. The power corresponding to 11% which is a difference from% can be used for charging the battery B, and the power corresponding to the remaining 9% cannot be used for charging the battery B. Therefore, the charging control unit 38b performs control to adjust the braking amount by the regenerative brake and the braking amount by the mechanical brake to 11: 9 so that the battery B can collect the electric power corresponding to 11%.

  Next, a method for controlling the riding lawnmower vehicle 1 having the above configuration will be described. FIG. 5 is a flowchart showing a method for controlling a riding lawn mower vehicle according to an embodiment of the present invention. In the flowchart shown in FIG. 5, the key operation by the operator is performed after the key operation is performed by the operator who is seated on the seat 15 on the ride type lawnmower vehicle 1 and the ride type lawnmower vehicle 1 is started. It is executed at regular time intervals until the riding-type lawn mowing vehicle 1 is stopped.

  When the processing of the flowchart shown in FIG. 5 is started, the vehicle speed of the riding lawn mowing vehicle 1 is first detected by the speed sensor 36 (step S11: first step), and then the riding lawn mowing vehicle 1 is detected by the 3D gyro sensor 37. Is detected (step S12: second step). The detection results of the speed sensor 36 and the 3D gyro sensor 37 are input to the regenerative power amount estimation unit 38a of the control device 38, and the regenerative power amount based on these detection results is estimated (step S13: third step).

  Specifically, the inertia energy of the riding lawn mowing vehicle 1 corresponding to the detection result of the speed sensor 36 is obtained using the table T1 shown in FIG. 3, and the detection result of the 3D gyro sensor 37 is obtained using the table T2. A corresponding gradient resistance for the riding lawn mowing vehicle 1 is obtained. And the electric energy of the regenerative electric power which the motor 41 generate | occur | produces is performed by performing various calculations by the calculating means 51-54 shown in FIG. 3 with respect to these inertial energy and distribution resistance.

  When the regenerative power amount is estimated by the regenerative power amount estimation unit 38a and the estimated regenerative power amount is a power amount that can charge the battery B, the charge amount of the battery B according to the estimated regenerative power amount Control is performed by the charge control part 38b (step S14: 4th step). Specifically, the relationship between the current state of charge of the battery B and the regenerative power amount estimated by the regenerative power amount estimation unit 38a is a region to which the reference symbol R1 in FIG. 4 is attached (region not hatched). When the relationship is included in the above, the charging control unit 38b performs control to apply the braking only by the regenerative brake without using the mechanical brake. By performing such control, the charging control unit 38 b causes the battery B to collect all the regenerative power generated by the motor 41.

  On the other hand, the relationship between the current state of charge of battery B and the amount of regenerative power estimated by regenerative power amount estimation unit 38a is included in the region indicated by symbol R2 in FIG. In such a relationship, the charging control unit 38b adjusts the braking force by the regenerative brake and the braking force by the mechanical brake, and performs control to apply braking using the mechanical brake in addition to the regenerative brake. Thereby, the charge state of the battery B is controlled so as not to exceed the target charge state. When the regenerative power amount estimated by the regenerative power amount estimation unit 38a is not the amount of power that can charge the battery B (for example, when the estimated regenerative power amount is zero or negative), the process proceeds to step S14. Processing is omitted.

  As described above, in the present embodiment, the speed sensor 36 and the 3D gyro sensor 37 detect the speed and the posture in the front-rear direction of the riding lawn mowing vehicle 1, respectively, and based on the detection results, the regenerative electric energy estimation unit 38a. Estimates the amount of regenerative power generated by the motor 41, and the charge amount control unit 38b controls the charge amount of the battery B according to the estimation result of the regenerative power amount estimation unit 38a. As a result, it is possible to perform appropriate charging control of the battery B using the regenerative power generated by the motor 41. As a result, the regenerative resistor can be downsized or the regenerative resistor can be made unnecessary. Effective use of energy can be achieved.

  As mentioned above, although the riding-type lawn mower vehicle and its control method by one Embodiment of this invention were demonstrated, this invention is not restrict | limited to the said embodiment, It can change freely within the scope of the present invention. For example, in the above embodiment, the example in which the regenerative power amount estimation unit 38b estimates the power amount of the regenerative power generated by the motor 41 using the tables T1 and T2 has been described. However, it is not always necessary to use the tables T1 and T2, and a motor using a function indicating the relationship between the speed and inertial energy of the riding lawn mowing vehicle 1 and a function indicating the relationship between the gradient resistance of the riding lawn mowing vehicle 1 and the motor. The amount of regenerative power generated at 41 may be estimated.

  In the above-described embodiment, an electric riding lawn mowing vehicle that travels using the power generated by the motor and cuts the lawn using the power generated by the motor has been described as an example. However, the present invention includes an engine and a motor as power generation sources, and can also be applied to a hybrid riding lawn mower vehicle that travels using power generated by these power generation sources. .

DESCRIPTION OF SYMBOLS 1 Passenger type lawn mowing vehicle 36 Speed sensor 37 3D gyro sensor 38a Regenerative electric energy estimation part 38b Charge control part 41 Motor B Battery T1, T2 Table

Claims (6)

In a riding-type lawn mower vehicle comprising a battery that supplies electric power and a motor that generates driving force for traveling by electric power from the battery,
A first sensor for detecting the speed of the vehicle;
A second sensor for detecting the attitude of the vehicle;
An estimation unit that estimates the amount of regenerative power generated by the motor based on the detection results of the first and second sensors;
A riding-type lawn mowing vehicle, comprising: a control unit that controls a charge amount of the battery according to an estimation result of the estimation unit.   The estimation unit obtains the inertia energy of the vehicle according to the detection result of the first sensor, obtains the gradient resistance for the vehicle according to the detection result of the second sensor, and uses the inertia energy and the gradient resistance. The riding lawn mowing vehicle according to claim 1, wherein the amount of regenerative power generated by the motor is estimated. The estimation unit includes a first table indicating a relationship between the speed of the vehicle and the inertial energy of the vehicle, and a second table indicating a relationship between the posture of the vehicle and the gradient resistance with respect to the vehicle,
Obtaining the inertia energy of the vehicle according to the detection result of the first sensor using the first table, and obtaining the gradient resistance for the vehicle according to the detection result of the second sensor using the second table. The riding-type lawn mowing vehicle according to claim 2.   The said control part controls the charge amount of the said battery so that the charge condition of the said battery may not exceed the preset target charge condition, The Claim 1 characterized by the above-mentioned. The described riding lawn mower vehicle. A first braking device that applies braking by collecting regenerative power generated by the motor in the battery;
A second braking device for braking by applying mechanical force to the wheels of the vehicle,
The control unit controls a charge amount of the battery by adjusting a braking amount of the first and second braking devices according to an amount of the regenerative power estimated by the estimation unit. The riding lawn mowing vehicle according to claim 4. A method for controlling a riding lawnmower vehicle, comprising: a battery that supplies electric power; and a motor that generates a driving force for traveling by the electric power from the battery,
A first step of detecting the speed of the vehicle;
A second step of detecting the attitude of the vehicle;
A third step of estimating the amount of regenerative power generated by the motor based on the detection results of the first and second steps;
And a fourth step of controlling a charge amount of the battery according to an estimation result of the third step.

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