JP2014128983A - Drive system for unmanned carrier - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drive system for an unmanned carrier in which a voltage of an electricity storage device can be suitably controlled.SOLUTION: An on-vehicle computer 21 of an unmanned carrier 11 estimates a regenerative electric power amount or an assist electric energy in a particular section on the basis of a loading weight and a travel pattern. A variation amount of a voltage of an electricity storage device 34 is calculated on the basis of the estimated regenerative electric power amount or assist electric energy, and an internal resistance. The on-vehicle computer 21 sets a target voltage on the basis of the calculated variation amount and an acceptable range of the voltage of the electricity storage device 34. The electricity storage device 34 is charged and discharged so that the voltage of the electricity storage device 34 is close to the target voltage before the unmanned carrier reaches the particular section.

Description

  The present invention relates to a drive system for an automated guided vehicle.

  Conventionally, in a manned hybrid vehicle, the voltage of a power storage device mounted on the hybrid vehicle has been controlled. For example, Patent Document 1 describes correcting cell voltage variations caused by differences in internal resistance of a plurality of battery cells.

JP 2004-227995 A

  Here, the present inventors generate power with an engine and a driving force of the engine from an excellent environment and economy in an automated guided vehicle (AGV) that travels on a predetermined travel route without an operator driving. Attention was focused on a hybrid that has a power storage device that can supply power to the generator motor and the generator motor and that can be charged by regenerative power generated by the generator motor. In this case, unlike the manned hybrid vehicle, the automatic guided vehicle has a characteristic that a traveling pattern is predetermined and the fluctuation range of the loaded weight is wide. Such characteristics affect the voltage control of the power storage device.

  For example, in a large automatic guided vehicle, the vehicle weight may differ by about 3 to 4 times between loading and non-loading. Then, the fluctuation range of the regenerative power amount or the like becomes wider, and as a result, the voltage of the power storage device may be out of the allowable range and the life may be shortened. However, a configuration that employs a power storage device with a wide allowable range is not preferable from the viewpoint of cost and increase in size. In addition, in a configuration where charging / discharging of the power storage device is forcibly interrupted so that the voltage of the power storage device does not fall outside the allowable range, the load on the engine mounted on the automatic guided vehicle can be increased or acquired. Inconveniences such as inability to obtain a sufficient amount of power.

  As described above, the above-mentioned characteristics peculiar to the automatic guided vehicle affect the voltage of the power storage device, but the fact is that no attention is paid to the voltage control of the power storage device in the automatic guided vehicle.

  The present invention has been made in view of the above-described circumstances, and an object of the present invention is to provide a driving system for an automatic guided vehicle capable of suitably performing voltage control of a power storage device.

  A drive system for an automatic guided vehicle that achieves the above object is capable of generating electric power by using an engine, a driving force of the engine and used for traveling, and is capable of supplying electric power to the generator / motor unit. A drive system for an automated guided vehicle having a power storage device that can be charged by regenerative power that can be generated by a generator motor, wherein the weight grasping unit grasps a loaded weight of the automated guided vehicle, and a traveling pattern of the automated guided vehicle A travel pattern grasping unit that grasps the power, an estimation unit that estimates a power fluctuation amount of the power storage device in a predetermined specific section based on the loaded weight and the travel pattern, and the power estimated by the estimation unit Based on a fluctuation amount and an internal resistance of the power storage device, a voltage fluctuation amount calculation unit that calculates a voltage fluctuation amount of the power storage device and a calculation result of the voltage fluctuation amount calculation unit. Based on, wherein the AGV is equipped with a voltage adjuster for adjusting a voltage of said power storage device before reaching the specific section.

  According to such a configuration, the estimation accuracy by the estimation unit is improved by including the loading weight that tends to widen the fluctuation range in the automatic guided vehicle as a parameter for estimating the power fluctuation amount of the power storage device in the specific section. be able to.

  Further, the amount of fluctuation of the voltage of the power storage device is calculated based on the amount of power fluctuation and the internal resistance estimated by the estimation unit, and based on the calculation result, before the automatic guided vehicle reaches the specific section, By adjusting the voltage, the voltage of the power storage device in the specific section can be within an allowable range. Thereby, voltage control of the power storage device can be suitably performed.

  The “power fluctuation amount of the power storage device in the specific section” is, for example, an assist power amount required to assist the traveling of the automatic guided vehicle when the specific section is an acceleration section or the like. Is a regenerative electric energy when is a deceleration zone or the like.

  The drive system for the automatic guided vehicle preferably includes an internal resistance deriving unit that derives an internal resistance of the power storage device when the automatic guided vehicle is started. According to such a configuration, it is possible to grasp variations in internal resistance by deriving the internal resistance when the automatic guided vehicle is started. Thereby, the voltage control of the power storage device can be more suitably performed by grasping the fluctuation of the voltage of the power storage device due to the variation in the internal resistance.

  Regarding the drive system for the automatic guided vehicle, the generator motor unit is configured to be able to rotate the engine using the electric power of the power storage device, and the internal resistance deriving unit is configured to adjust the rotation of the engine. It is preferable to measure the voltage fluctuation of the power storage device with respect to the current fluctuation of the power storage device caused by the above, and derive the internal resistance of the power storage device from the measurement result. According to this configuration, by adjusting the rotation of the engine, the resistance of the load connected to the power storage device is adjusted, and the current of the power storage device varies. Then, the internal resistance of the power storage device is derived by measuring the voltage variation of the power storage device with respect to the current variation. Thereby, internal resistance can be suitably derived | led-out using existing structures, such as an engine.

  According to the present invention, voltage control of the power storage device can be suitably performed.

The schematic diagram of the container terminal to which the drive system of an automatic guided vehicle is applied. The conceptual diagram which shows the drive system of an automatic guided vehicle. The block diagram which shows the structure of an automatic guided vehicle. The flowchart which shows the traveling control process performed with a vehicle-mounted computer. (A) is a graph which shows the fluctuation | variation of the speed of an automatic guided vehicle, (b) is a graph which shows the fluctuation | variation of the voltage of an electrical storage apparatus.

Hereinafter, an embodiment in which a driving system for an automatic guided vehicle is applied to a container terminal in a harbor will be described.
First, an overview of the container terminal will be described. As shown in FIG. 1, the container terminal includes a gantry crane C1 disposed near the container ship S and loading / unloading containers, and a rubber tire crane C2 disposed at the container installation site and loading / unloading containers. Is provided.

  In the container terminal, the automatic guided vehicle (AGV) 11 circulates in a predetermined direction (for example, counterclockwise) on a travel route R defined by a guide portion such as a guide line. The automatic guided vehicle 11 is configured to be able to load containers, and carries containers near the container ship S and between container installation sites. For example, when a container is loaded on the automatic guided vehicle 11 by the gantry crane C1, the automatic guided vehicle 11 transports the container to the container installation site. When the automatic guided vehicle 11 arrives at the container installation site, the container is lowered by the rubber tire crane C2. After the container is lowered, the automatic guided vehicle 11 travels again toward the gantry crane C1. In the present embodiment, it is assumed that the travel route R is flat without an inclination.

  Next, the drive system 10 of the automatic guided vehicle 11 that goes around as described above will be described. As shown in FIG. 2, the drive system 10 of the automatic guided vehicle 11 includes an in-vehicle computer 21 mounted on the automatic guided vehicle 11 and an operation management computer 22 capable of wireless communication with the in-vehicle computer 21. The operation management computer 22 controls the traveling of the automatic guided vehicle 11 by transmitting various commands to the in-vehicle computer 21. Moreover, the operation management computer 22 performs drive control of the gantry crane C1 and the rubber tire crane C2.

  Next, a specific configuration of the automatic guided vehicle 11 will be described. The automatic guided vehicle 11 of this embodiment is a so-called series type hybrid vehicle. Specifically, as shown in FIG. 3, the automatic guided vehicle 11 includes an engine 31, a first generator motor (first motor generator) 32 that can generate power by the driving force of the engine 31, and the first generator motor 32. And a power generation inverter 33 connected thereto. Furthermore, the automatic guided vehicle 11 includes a power storage device 34 connected to the power generation inverter 33, a travel inverter 35 connected to the power storage device 34 and the power generation inverter 33, and a second generator motor (second motor) connected to the travel inverter 35. Motor generator) 36. In FIG. 3, only one traveling inverter 35 and two second generator motors 36 are illustrated, but actually, a plurality of them are provided according to the number of axles of the automatic guided vehicle 11. Each of the inverters 33 and 35 converts to DC power when DC power is input and outputs the AC power, and converts and outputs DC power when AC power is input.

  The first generator motor 32 has a rotor connected to the drive shaft of the engine 31, and generates AC power when the rotor rotates as the drive shaft of the engine 31 rotates. On the other hand, the first generator motor 32 can also operate as a load by rotating the engine 31 when AC power is input.

  The second generator motor 36 is used for traveling. Specifically, the rotor of the second generator motor 36 is coupled to the axle, and electric power is input from at least one of the generator inverter 33 (first generator motor 32) and the power storage device 34 via the travel inverter 35. If this happens, rotate the axle. On the other hand, the second generator motor 36 has a regenerative function for converting kinetic energy into electric energy, and generates power by performing regenerative braking when the automatic guided vehicle 11 is decelerated. The first generator motor 32 and the second generator motor 36 correspond to the generator motor unit.

A clutch (not shown) is provided between the second generator motor 36 and the axle, and the in-vehicle computer 21 is configured to be able to control the clutch.
The power storage device 34 has an internal resistance. The power storage device 34 is composed of, for example, a nickel metal hydride battery or a lithium ion battery, can supply power to the first generator motor 32 via the power generation inverter 33, and supplies power to the second generator motor 36 via the travel inverter 35. Can be supplied. The power storage device 34 is charged by the electric power generated by the generator motors 32 and 36 being input via the inverters 33 and 35.

  Incidentally, an allowable range in which the power storage device 34 is unlikely to deteriorate is set in the SOC (charging state, charging rate) of the power storage device 34. The allowable range is set in advance according to the specifications of the power storage device 34, and a lower limit value and an upper limit value are set.

  Similarly, an allowable range in which the power storage device 34 is unlikely to deteriorate is set for the voltage of the power storage device 34. The allowable range is set in advance according to the specifications of the power storage device 34, and an upper limit value and a lower limit value are set.

  The in-vehicle computer 21 is configured to favorably accelerate / decelerate the automatic guided vehicle 11 by controlling charging / discharging of the power storage device 34. For example, at the time of acceleration, the in-vehicle computer 21 generates power by the first generator motor 32 by driving the engine 31, supplies the generated power to the second generator motor 36, and discharges the power storage device 34. Discharge electric power is supplied to the 2nd generator motor 36, and the driving | running | working of the automatic guided vehicle 11 and the power running in detail are assisted. The discharge power of the power storage device 34 supplied to the second generator motor 36 is referred to as assist power.

On the other hand, at the time of deceleration, the in-vehicle computer 21 supplies the regenerative power generated by the second generator motor 36 to the power storage device 34 and charges the power storage device 34.
The automatic guided vehicle 11 includes a power storage sensor 37 that measures the voltage and current of the power storage device 34. The power storage sensor 37 transmits the measured voltage of the power storage device 34 and the like to the in-vehicle computer 21. The automatic guided vehicle 11 includes a load sensor 38 as a weight grasping unit that measures the loaded weight (load) of the automatic guided vehicle 11 and transmits the measurement result to the in-vehicle computer 21. Thereby, the vehicle-mounted computer 21 can grasp the voltage and current of the power storage device 34 and the loaded weight.

  Here, when driving the automatic guided vehicle 11, the operation management computer 22 transmits a travel pattern in which the acceleration / deceleration pattern of the automatic guided vehicle 11 is set to the in-vehicle computer 21 together with the travel command. When the in-vehicle computer 21 receives the travel command and the travel pattern from the operation management computer 22, the in-vehicle computer 21 causes the automatic guided vehicle 11 to travel according to the received travel pattern.

  In the travel pattern, the travel distance, travel speed, acceleration, and the like of the automatic guided vehicle 11 traveling on the travel route R are set, and the automatic guided vehicle 11 is set to travel while repeating acceleration and deceleration. For example, in the traveling route R, the traveling speed of the corner portion is set lower than the traveling speed of the straight portion. That is, in the travel route R, an acceleration section and a deceleration section are set as specific sections. And the vehicle-mounted computer 21 can grasp | ascertain an acceleration area and a deceleration area before the automatic guided vehicle 11 arrives at an acceleration area and a deceleration area by grasping | ascertaining a driving pattern.

  Here, the internal resistance and allowable range (lower limit value, upper limit value) of the power storage device 34 are the voltage of the power storage device 34 when the automatic guided vehicle 11 whose internal resistance of the power storage device 34 is the initial value travels according to the travel pattern. Is set to be within an allowable range. However, depending on the loading weight of the container loaded on the automatic guided vehicle 11, the voltage of the power storage device 34 may be outside the allowable range. Further, the internal resistance of the power storage device 34 may vary due to repeated charging / discharging of the power storage device 34, manufacturing variations, and the like. In this case, depending on how the internal resistance varies, the voltage of the power storage device 34 may be outside the allowable range.

  On the other hand, the in-vehicle computer 21 executes a travel control process for causing the automatic guided vehicle 11 to travel while performing voltage control of the power storage device 34 in consideration of the loaded weight and the internal resistance of the power storage device 34. The travel control process will be described with reference to FIG. The traveling control process is a process that is periodically executed by the in-vehicle computer 21.

  First, in step S101, it is determined whether or not the automatic guided vehicle 11 is started. Specifically, it is determined whether or not a travel command is received from the operation management computer 22. The travel command is transmitted from the operation management computer 22 periodically, for example, at a predetermined time every day.

  If the travel command has not been received, the travel control process is terminated as it is. If the travel command has been received, an open-circuit voltage (OCV) determination process is executed in steps S102 and S103. To do.

  Specifically, in step S102, the voltage of the power storage device 34 is measured. In subsequent step S103, the voltage measured in step S102 is stored as an open voltage in a storage area provided in the in-vehicle computer 21.

  After determining the open circuit voltage, the internal resistance derivation process of the power storage device 34 is executed in steps S104 to S107. Specifically, first, in step S104, constant current discharge in which a constant current flows in the power storage device 34 is started. In this case, the in-vehicle computer 21 controls to supply the electric power discharged from the power storage device 34 to the first generator motor 32. The first generator motor 32 rotates the engine 31 using the discharge power of the power storage device 34. When performing constant current discharge, the clutch is not connected.

  In step S105, the voltage of power storage device 34 is measured. Here, the in-vehicle computer 21 varies the constant current value by controlling the rotation speed of the engine 31 at a predetermined timing during the constant current discharge, and measures the voltage at each constant current value.

  After voltage measurement, the discharge is terminated in step S106. In step S107, based on the measurement result, an IV plot is created with the open-circuit voltage determined in step S103 as an intercept, and the internal resistance is derived from the slope of the IV plot. The internal resistance is stored in a predetermined storage area of the in-vehicle computer 21. Note that the processing from step S104 to step S107 corresponds to the internal resistance deriving unit.

After the process of step S107 is complete | finished, pattern driving | running | working is performed in step S108-step S117.
First, in step S108, traveling is started based on the traveling pattern received together with the traveling command. Then, the process of step S109-step S116 is performed in the constant speed area which is the timing before a specific area (acceleration / deceleration area) and the automatic guided vehicle 11 travels at a constant speed. In the constant speed section, regenerative power is not generated, and the assist power amount is “0” or smaller than that during acceleration.

  First, in step S109, the load sensor 38 grasps the loaded weight of the automatic guided vehicle 11. In step S110, the traveling pattern is grasped, and the distance (or acceleration / deceleration time) of the specific section, acceleration, and the like are grasped. The process of step S110 corresponds to a travel pattern grasping unit.

  In the subsequent step S111, the regenerative power amount or the assist power amount is estimated based on the travel pattern and the loaded weight. Specifically, for example, before the deceleration section, the amount of regenerative electric power generated in the deceleration section is estimated, and before the acceleration section, the automatic guided vehicle 11 is assisted (powering) in the acceleration section. The amount of assist power required for this is estimated. The processing in step S111 corresponds to the estimation unit.

  Thereafter, in step S112, the current open circuit voltage is estimated. Specifically, the SOC fluctuation amount is calculated from the quotient of the integrated current value and the battery capacity. Then, the current SOC is estimated from the fluctuation amount and the initial value of the open circuit voltage set in step S103, and the current open circuit voltage is estimated from the current SOC.

  After estimating the current open circuit voltage, in step S113, based on the regenerative power amount or assist power amount estimated in step S111 and the open circuit voltage estimated in step S112, the power storage in the specific section is performed. The current of the device 34, that is, the regenerative current or the assist current is calculated.

  Thereafter, in step S114, the fluctuation amount of the voltage of the power storage device 34 is calculated (derived) based on the internal resistance derived in step S107 and the current of the power storage device 34 calculated in step S113. Specifically, for example, the amount of voltage increase is calculated before the deceleration section, and the amount of voltage drop is calculated before the acceleration section. The processing from step S112 to step S114 corresponds to the voltage fluctuation amount calculation unit.

  In step 115, the target voltage is set in consideration of the allowable range of power storage device 34. For example, before the deceleration section, a voltage obtained by subtracting the amount of voltage increase from the upper limit value of the voltage of the power storage device 34 or a voltage lower than that is set as the target voltage. For example, before the acceleration section, a voltage obtained by adding a voltage drop amount to the lower limit value of the voltage of the power storage device 34 or a voltage higher than that is set as the target voltage.

  In step S116, the voltage of the power storage device 34 is adjusted so that the voltage of the power storage device 34 approaches the target voltage set in step S115 before the automatic guided vehicle 11 reaches the specific section. Specifically, charge / discharge control of power storage device 34 is performed so that the SOC of power storage device 34 approaches the target SOC corresponding to the target voltage. Note that the processing in step S116 can also be said to be SOC adjustment processing. The processing in step S116 corresponds to the voltage adjustment unit.

  When the current voltage is higher than the target voltage in the constant speed section before the acceleration section, the power storage device 34 is not charged / discharged, and the current voltage is higher than the target voltage in the constant speed section before the deceleration section. If it is lower, the power storage device 34 is not charged or discharged.

  Thereafter, in step S117, acceleration / deceleration processing is executed when the automatic guided vehicle 11 reaches a specific section. Specifically, for example, regenerative power is supplied to the power storage device 34 in the deceleration zone, and power stored in the power storage device 34 is supplied to the traveling inverter 35 in the acceleration zone. In this case, power control is performed so that the voltage of the power storage device 34 falls within the allowable range. Specifically, for example, when the voltage of the power storage device 34 reaches an upper limit value during deceleration, charging of the power storage device 34 is interrupted and the remaining regenerative power is supplied to the first generator motor 32. Similarly, for example, when the voltage of the power storage device 34 reaches the lower limit during acceleration, the discharge of the power storage device 34 is interrupted.

  After the acceleration / deceleration of the automatic guided vehicle 11 is completed, the process proceeds to step S118, and it is determined whether or not the pattern traveling is completed. If the pattern travel has not ended, the process returns to step S109, whereas if the pattern travel has ended, the present travel control process ends.

  Next, the effect | action of this embodiment is demonstrated using FIG. FIG. 5A is a graph showing the fluctuation (travel pattern) of the speed of the automatic guided vehicle 11, and FIG. 5B is a graph showing the fluctuation of the voltage of the power storage device 34. For convenience of explanation, the deceleration section Td and the voltage of the power storage device 34 before that will be described.

  As shown in FIG. 5A, the traveling pattern of the automatic guided vehicle 11 is switched to acceleration, constant speed, or deceleration at timings t1 to t8. Corresponding to this, as shown in FIG. 5B, the voltage of the power storage device 34 fluctuates. In this case, as shown by a two-dot chain line in FIG. 5B, when there is no variation in the internal resistance, specifically, when the internal resistance does not vary from the initial value, the voltage of the power storage device 34 is within an allowable range. It is within.

  Here, for example, as shown in the one-dot chain line and section X in FIG. 5B, when the internal resistance of the power storage device 34 varies, the voltage of the power storage device 34 reaches the upper limit during deceleration, and the power storage device There may be a situation where 34 cannot absorb the regenerative power. In particular, when the internal resistance increases, the amount of increase in voltage is likely to increase, so the above situation is likely to occur.

  On the other hand, as shown by the solid line in FIG. 5B, the pre-adjustment section Tpr that reduces the voltage of the power storage device 34 in advance is provided before the deceleration section Td, so It is avoided that the voltage of the device 34 exceeds the upper limit value. For this reason, all the regenerative power generated in the deceleration zone Td is used for charging the power storage device 34. Further, in the pre-adjustment section Tpr, the automatic guided vehicle 11 travels using the electric power of the power storage device 34, and the power generation amount of the first generator motor 32 becomes small.

  In the constant speed section from the timing t4 to the timing t5 as before the acceleration section Ta, the voltage of the power storage device 34 is an upper limit value. The voltage of the power storage device 34 is higher than the target voltage that should be close to the timing t5. For this reason, even if the voltage adjustment of the electrical storage device 34 is not performed, the power running in the acceleration section Ta from the timing t5 to the timing t6 is assisted.

According to the embodiment described in detail above, the following excellent effects are obtained.
(1) Based on the load weight and the running pattern, the amount of power fluctuation of the power storage device 34 in the specific section, specifically, the amount of assist power or the amount of regenerative power is estimated, and based on the estimated amount of power fluctuation and internal resistance. Thus, the voltage fluctuation amount is calculated. Then, before the automatic guided vehicle 11 reaches the specific section, the voltage of the power storage device 34 is adjusted based on the calculated voltage fluctuation amount. Thereby, while suppressing that the voltage of the electrical storage device 34 is outside the allowable range in the specific section, all the regenerative power can be used for charging in the deceleration section Td, and power running can be assisted in the acceleration section Ta. it can. Therefore, it is possible to extend the life of the power storage device 34 and improve fuel efficiency.

  In particular, since the automatic guided vehicle 11 has a larger fluctuation range of the loaded weight than that of a normal vehicle such as an automobile because of loading containers, the fluctuation range of the regenerative electric power accompanying the fluctuation of the loaded weight becomes wider. easy. In addition, the automatic guided vehicle 11 is different from a normal vehicle in that a traveling pattern is determined in advance.

  In this regard, in this embodiment, paying attention to the unique characteristics of the automatic guided vehicle 11 described above, a configuration in which the loaded weight and the traveling pattern are taken into account when estimating the regenerative power amount or the assist power amount is adopted. Thus, it is possible to improve the estimation accuracy of the regenerative power amount or the assist power amount. Thereby, voltage control of the electrical storage device 34 can be performed more suitably.

  (2) A target voltage is set based on the amount of voltage fluctuation and the allowable range of the power storage device 34, and the voltage of the power storage device 34 is adjusted so that the voltage of the power storage device 34 approaches the target voltage before reaching the specific section. It was set as the structure to do. For example, before the deceleration section Td, a value obtained by subtracting the amount of voltage fluctuation from the upper limit value of the voltage of the power storage device 34 is set as the target voltage, and the voltage is adjusted so as to approach the target voltage. This avoids a situation where the regenerative power cannot be completely absorbed or power running cannot be assisted due to the voltage of the power storage device 34 reaching the upper limit value or the lower limit value in the middle of the specific section. can do.

  (3) The internal resistance is derived every time the automatic guided vehicle 11 is started. Thereby, the dispersion | variation in internal resistance can be grasped | ascertained suitably. Therefore, the fluctuation amount of the voltage of the power storage device 34 can be calculated in consideration of the variation in the internal resistance. Therefore, even when the internal resistance varies, the effects (1) and (2) are achieved.

  (4) The in-vehicle computer 21 is configured to vary the resistance of the load to which the electric power of the power storage device 34 is supplied by adjusting the rotation of the engine 31 before starting running. Thereby, the current of power storage device 34 varies. The in-vehicle computer 21 is configured to derive the internal resistance by measuring the voltage fluctuation with respect to the current fluctuation by the power storage sensor 37. Thereby, an IV plot can be created using the existing configuration of the engine 31 and the like, and the internal resistance can be derived therethrough.

In addition, you may change the said embodiment as follows.
Focusing on the fact that the internal resistance of the power storage device 34 varies depending on the temperature, a temperature sensor that detects the temperature of the power storage device 34 may be provided, and the internal resistance may be corrected from the detection result of the temperature sensor.

  The operation management computer 22 may be configured to store inclination information related to the inclination of the travel route R in a predetermined storage area. And the operation management computer 22 is good also as a structure which transmits the inclination information of the driving | running route R to the vehicle-mounted computer 21 in addition to a driving | running pattern. In this case, the in-vehicle computer 21 grasps the inclination in the deceleration zone Td or the acceleration zone Ta before executing the process of step S111. And the vehicle-mounted computer 21 is good also as a structure which estimates regenerative electric energy or assist electric energy based on a loading weight, a travel pattern, and an inclination in step S111. Thereby, the further improvement of the estimation precision of regenerative electric energy or assist electric energy can be aimed at.

  In the embodiment, the acceleration section Ta and the deceleration section Td are set as specific sections. However, the present invention is not limited to this, and the section in which the power storage device 34 is charged and the section in which the power storage device 34 is discharged are set. It only has to be done. For example, a downward section that is inclined downward may be set as a section where the power storage device 34 is charged, or an upward section that is inclined upward may be set as a section where the power storage device 34 is discharged. Good.

  In the embodiment, when deriving the internal resistance, the current of the power storage device 34 is varied by controlling the number of revolutions of the engine 31. However, the present invention is not limited to this. A configuration may be adopted in which the resistance of the variable resistor is varied while discharging is performed in a state of being connected to the variable resistor. In short, as long as an IV plot can be created, its specific configuration is arbitrary.

  ○ In step S113, the regenerative current or assist power is calculated based on the regenerative power amount or assist power amount and the open circuit voltage. However, the present invention is not limited to this. Based on this, it may be configured to calculate the regenerative current or the assist current.

  In the embodiment, the internal resistance is derived before starting traveling. However, the present invention is not limited to this, and the internal resistance may be derived during traveling. However, in consideration of the accuracy of deriving the internal resistance, it is preferable to derive it before traveling.

  In addition, the execution timing of the internal resistance derivation process is not limited to the case where the automatic guided vehicle 11 is started, but is arbitrary. For example, a configuration in which a predetermined time has elapsed since the last operation of the automatic guided vehicle 11 is completed, or a configuration in which the operation is periodically performed at a predetermined time may be employed.

  In the embodiment, the load sensor 38 is used to measure the load weight, but the structure for determining the load weight is arbitrary. For example, it is good also as a structure which estimates load weight from the electric energy required at the time of acceleration, good also as a structure acquired by radio | wireless communication from the operation management computer 22, and the measurement measured by the gantry crane C1 or the rubber tire crane C2. The structure which acquires a result may be sufficient.

In the embodiment, the power storage device 34 is a nickel metal hydride battery or a lithium ion secondary battery, but is not limited thereto, and may be, for example, an electric double layer capacitor.
O While the automated guided vehicle 11 is stopped, the automated guided vehicle 11 may be configured to stop the engine 31 and stand by using only the electric power of the power storage device 34.

O When the front signal of the automatic guided vehicle 11 is a red signal, or when the automatic guided vehicle 11 in front is decelerating, the power storage device 34 may be discharged in advance.
In embodiment, although the vehicle-mounted computer 21 was the structure which performs a series of control, it is not restricted to this, The structure which a some control part performs various control may be sufficient. That is, the control subject of the engine 31 and the generator motors 32 and 36 is arbitrary.

  In the embodiment, the operation management computer 22 is configured to perform drive control of the cranes C1 and C2. However, the present invention is not limited to this, and another management computer may be configured to perform drive control.

In the embodiment, two second generator motors 36 are provided. However, the second generator motor 36 is not limited thereto, and may be three or more, or may be one.
○ When the current voltage is higher than the target voltage in the constant speed section before the acceleration section, the power storage device 34 may be discharged so as to approach the target voltage, or in the constant speed section before the deceleration section. When the current voltage is lower than the target voltage, the power storage device 34 may be charged so as to approach the target voltage.

  In the embodiment, the automatic guided vehicle 11 distinguishes between the first generator motor 32 that can generate power by the driving force of the engine 31 and the second generator motor 36 that can run the automatic guided vehicle 11 and generate regenerative power. Although it is a so-called series-type hybrid vehicle, it is not limited to this. For example, it may be a hybrid vehicle of another method such as a so-called parallel method in which both functions are executed by one generator motor. In short, the automatic guided vehicle 11 includes an engine 31, a power generation motor unit that can generate electric power by the driving force of the engine 31, can run the automatic guided vehicle 11, and can generate regenerative power, and a power storage device 34. If it is, the specific configuration is arbitrary.

Next, the technical idea that can be grasped from the above embodiment and other examples will be described below.
(A) The voltage adjusting unit adjusts the target voltage derived based on an allowable range of the voltage of the power storage device and a calculation result of the voltage fluctuation amount calculating unit before the automatic guided vehicle reaches the specific section. The drive system of the automatic guided vehicle as described in any one of Claims 1-3 which adjusts the voltage of the said electrical storage apparatus so that it may approach.

  (B) The voltage adjustment unit adjusts the voltage of the power storage device by controlling charging and discharging of the power storage device, and the automatic guided vehicle according to any one of claims 1 to 3 and (A). Drive system.

  (C) The generator motor section includes a first generator motor that can generate power with the driving force of the engine, and a second generator motor that is used for traveling and can generate regenerative power. The driving system for the automatic guided vehicle according to any one of?

  DESCRIPTION OF SYMBOLS 10 ... Drive system of automatic guided vehicle, 11 ... Automatic guided vehicle, 21 ... In-vehicle computer, 31 ... Engine, 32 ... 1st generator motor, 34 ... Power storage device, 36 ... 2nd generator motor.

Claims (3)

An engine, a generator motor that can generate power with the driving force of the engine and used for traveling, and can supply power to the generator motor and can be charged by regenerative power that can be generated by the generator motor A drive system for an automated guided vehicle having a power storage device,
A weight grasping unit for grasping a loading weight of the automatic guided vehicle;
A traveling pattern grasping unit for grasping a traveling pattern of the automatic guided vehicle;
An estimation unit configured to estimate a power fluctuation amount of the power storage device in a predetermined specific section based on the loaded weight and the traveling pattern;
A voltage fluctuation amount calculation unit that calculates a voltage fluctuation amount of the power storage device based on the power fluctuation amount estimated by the estimation unit and an internal resistance of the power storage device;
Based on the calculation result of the voltage fluctuation amount calculation unit, a voltage adjustment unit that adjusts the voltage of the power storage device before the automatic guided vehicle reaches the specific section;
A drive system for an automated guided vehicle comprising:   The drive system for an automatic guided vehicle according to claim 1, further comprising an internal resistance deriving unit that derives an internal resistance of the power storage device when the automatic guided vehicle is started. The generator motor unit is configured to be able to rotate the engine using electric power of the power storage device,
The internal resistance deriving unit measures a change in voltage of the power storage device with respect to a change in current of the power storage device caused by adjusting the rotation of the engine, and derives the internal resistance of the power storage device from the measurement result. The drive system for an automatic guided vehicle according to claim 2.