KR101061027B1 - Moving object - Google Patents

Abstract

(Configuration) The stacker crane is provided with an electric double layer capacitor and a capacitor control unit, and a power control unit for switching the power supply between the power receiving coil and the capacitor receiving from the non-contact feed line. The regenerative energy predictor 24 predicts the regenerative power based on the transfer instruction to the stacker crane, and the power supply coil and the capacitor based on the output voltage of the receiving coil, the output voltage of the electric double layer capacitor, and the predicted regenerative energy. Install a capacitor control table to switch between.

(Effect) The power supply capacity of the main power supply can be reduced, and there is no need to consume the regenerative power from the motor as a resistor.

Moving object

Description

Mobile body {MOVING BODY}

The present invention relates to power supply to a mobile body, and more particularly, to an auxiliary power source capable of charging and discharging.

It is known to use an auxiliary power supply such as an electric double layer capacitor or a Ni-hydrogen battery in order to level power consumption from a feeder in a stacker crane or a moving vehicle such as a ceiling running car or a trolley bogie (Patent Document 1). . However, in Patent Literature 1, only the regenerative power is charged to the auxiliary power, so that the power that can be supplied at the peak of the power is small, and when the regenerative power is not obtained, the power that can be drawn from the auxiliary power becomes smaller.

[Patent Document 1] Japanese Patent Publication 2003-63613

An object of the present invention is to make the capacity of the main power supply smaller by charging the auxiliary power supply with the surplus power and the regenerative power of the main power supply. A further problem in the invention of claim 2 is to control the auxiliary power supply by simple control to absorb the regenerative power and to level the power of the main power supply. A further problem in the invention of claim 3 is to ensure that the regenerative power can be reliably absorbed even by the auxiliary power supply having a small capacity.

The present invention includes a main power source, an auxiliary power source capable of charging and discharging, a power regenerative type motor, and a mobile body including a load operated by each of the power sources, wherein the moving body is discharged at a peak time of the motor. And a control unit for controlling the auxiliary power so as to be charged with regenerative power from the motor and surplus power of the main power.

Preferably, the control unit switches the connection between the auxiliary power source, the main power source and the load so that when the charge amount of the auxiliary power source exceeds a first predetermined value, the auxiliary power source is discharged from the auxiliary power source to drive the load. The auxiliary power is charged by the main power supply except for the peak amount of the charge and the power supply of the motor is exceeded, and the auxiliary power is charged by regenerative power from the motor. The first predetermined value and the second predetermined value may be the same values. Further, the first predetermined value is preferably a value smaller than the rated charging amount of the auxiliary power supply as long as it can absorb the regenerative power, and the second predetermined value is preferably a value that can be further discharged from the auxiliary power supply at the peak of power. Preferably, a prediction means for estimating the energy regenerated by the motor from the operation command to the moving body is provided, and the control unit controls the amount of charge of the auxiliary power to be less than or equal to a value capable of absorbing the regenerative energy. do.

(Effects of the Invention)

In the present invention, since the auxiliary power is charged with the regenerative power and the surplus power of the main power, large power can be accumulated. In particular, even when the moving body continues to operate without generating regenerative power, the auxiliary power can be charged at a time other than the peak of the power, and the power of the main power can be leveled.

Here, when the auxiliary power is discharged because the charging amount of the auxiliary power exceeds the first predetermined value, it is possible to make the charging amount have a margin sufficient to absorb the regenerative power. If the auxiliary power is less than the second predetermined value and the auxiliary power is charged by the main power other than at the peak of the electric power of the motor, the electric power as much as backing up the main power can be accumulated. In addition, if the charging amount of the auxiliary power supply is controlled to be equal to or less than the value capable of absorbing the regenerative energy by providing a prediction means for estimating the energy regenerated by the motor from the operation command to the moving object, the charging amount of the auxiliary power can be as long as possible. In addition, it is possible to reliably absorb the regenerative power.

Best Mode for Carrying Out the Invention The following shows an optimal embodiment.

[Example]

1 to 6 show the stacker crane 2 as an example of the movable body in the embodiment. Examples of the mobile body include a stacker crane, a railroad cart, and the like, in addition to the stacker crane. 4 is a high frequency power supply, it feeds to the power receiving coil 6 as a main power supply by the non-contact power supply via the high frequency feed line 5, and the high frequency feed line 5 is provided in parallel with the travel rail of the stacker crane 2. As shown in FIG.

8 is a power supply control part, and the electric double layer capacitor control part 10 controls the electric double layer capacitor 12, and may be a capacitor | condenser other than an electric double layer capacitor, a rechargeable secondary battery, etc. The power supply control unit 8 controls the connection of the power receiving coil 6 and the capacitor control unit 10, and various control units 14 to 17 and the job power source 18. The current supplied from the power receiving coil 6 to the power supply control section 8 is is and the voltage of the power receiving coil is vs. These are data representing the state on the main power supply side. The current between the capacitor control unit 10 and the power supply control unit 8 is ic and the capacitor voltage is vc. These are data representing the state of the electric double layer capacitor 12. The control signal from the power supply control section 8 to the capacitor control section 10 is referred to as dc. The current flowing from the capacitor control unit 10 to the power control unit 8 is called discharging. At this time, the current ic becomes + and the current flowing from the power control unit 8 to the capacitor control unit 10 is called charging. At this time, the current ic becomes-.

M1 to M4 are driving motors, and all of them are power regenerative motors, but at least the traveling motor M1 and the lifting motor M2 are power regenerative motors. Moreover, M3 is a turning motor for turning a moving means, such as a slide fork, on the platform of the stacker crane 2, M4 is a drive motor of a slide fork. The moving means is not limited to the slide fork but may be a scalar arm or the like. The traveling control unit 14 drives the traveling motor M1 by VVVF control or the like, the lifting control unit 15 controls the lifting motor M2 in a similar manner, and the turning control unit 16 controls the turning motor M3 by the fork control unit. 17 controls the fork drive motor M4 in a similar manner. The job power source 18 supplies electric power to a fan of the fan filter unit 20 and also supplies electric power to the main control unit 22 that controls the entire stacker crane 2. The main controller 22 supplies a control signal to each control unit from the power supply control unit 8 to the power supply unit 18 and the fan filter unit 20.

As shown in FIG. 2, the regenerative energy prediction part 24 is provided in the power supply control part 8, and the quantity of the regenerative energy which generate | occur | produces afterwards is estimated. Prediction of the regenerative energy is based on the conveyance instruction | command from the main control part 22, and the position which loads and the position which loads are shown by the conveyance instruction | command. As a result, the stacker crane 2 travels empty from the current position to the position where the loading is performed, and lifts the platform up to the height at which the loading is performed. After loading, the vehicle travels and lifts up and down to the actual load to the position where the load is unloaded. In these processes, regenerative energy is generated by the deceleration of the traveling motor and the lowering of the platform.

The regenerative energy from the traveling motor is generated in the process of decelerating the stacker crane. The regenerative energy generated at the deceleration is determined by the speed at the start of deceleration and the weight of the entire stacker crane including the weight of the article. Therefore, when the traveling distance is short and the deceleration starts when the stacker crane does not reach the normal speed, the regenerative energy is small. The regenerative energy from the lifting motor is generated by the lowering of the actual load or the empty load, and the regenerative energy of the actual load increases. The regenerative energy predicting unit 24 stores as a constant for converting the running speed and the height of the lift and the distinction between the actual load and the empty load by the conveyance command into the regenerative energy.

The capacitor control table 26 reflects to the control the state of the power receiving coil 6 side of the main power supply based on the output voltage vs of the power receiving coil 6 or the output current is from the power receiving coil. In the electric double layer capacitor 12, the charge amount is evaluated based on the capacitor voltage vc, and the charge amount of the electric double layer capacitor 12 is changed within a predetermined range. The excess portion is allocated to the driving of another load so that the regenerative energy predicted by the regenerative energy predicting unit 24 consumes the regenerative energy generated by the lifting motor M2 in the traveling motor M1, for example. It is used for charging the capacitor 12. The capacitor control table 26 stores data necessary for their control.

3-6, the data of the capacitor control table 26 is shown typically. The voltage vc of the electric double layer capacitor has a maximum value and a minimum value, and changes the capacitor voltage vc within this range. The control center is installed near the center of the fluctuation range of the capacitor voltage vc, and the overcharge is discharged when the capacitor voltage increases from the voltage at which the predetermined margin is added to the control center, and the predetermined margin is subtracted from the voltage of the control chief referee. If the capacitor voltage is lower than the voltage, the shortage is charged. Even when the capacitor voltage vc is within the discharge range, when regenerative energy is generated, it is absorbed (charged). When the capacitor voltage vc is within the charge range, the capacitor coil vc is discharged so as to compensate for it. The margin may be 0, and the voltage having the margin added to the control center is the first predetermined value, and the voltage obtained by subtracting the margin from the control center is the second predetermined value. The state on the main power supply side is evaluated from the output voltage vs of the power receiving coil, and backed up to the electric double layer capacitor so that the output voltage vs of the power receiving coil does not fall below its minimum value.

The capacitor control table describes the distinction of whether the electric double layer capacitor is discharged or charged, or the electric double layer capacitor is not operated (charge / discharge current = 0), and whether charging or discharging is described as only on / off data. The charge or discharge current ic may be described in more detail. When the capacitor voltage vc increases from the control center, it is discharged from the capacitor, and when decreased, it is charged with the capacitor. When the power receiving coil voltage vs is increased above the control center, it is charged that excess power is generated, and when it is lower than the control center, it is discharged to back up the main power supply. The predicted regenerative energy decreases the maximum value of the capacitor voltage vc in the table, and discharges when the capacitor voltage vc becomes larger than the smaller value corresponding to the predicted regenerative energy from the maximum value of the charge amount.

4 shows a target value of the discharge current ic along the diagonal direction between the upper left and the lower right of the table of FIG. 3. It discharges in the area | region where the capacitor voltage is high and the power receiving coil voltage is low. Also, the capacitor voltage is lowered in advance so as to absorb the regenerative energy generated next time. Charges when the output voltage of the power receiving coil is high and the capacitor voltage drops.

FIG. 5 illustrates data along the V-V direction of FIG. 3. Since there is a margin in the output voltage vs of the receiving coil, the capacitor voltage vc is controlled to be near the control center, and the control is performed to enable the charging of the predicted regenerative energy.

FIG. 6 shows control data along the Vi-Vi line of FIG. 3. In this case, since the output voltage (vs) of the receiving coil is low, the capacitor is discharged and backed up. In this case, the regenerative energy can be absorbed by the discharge from the capacitor. The state of FIG. 6 is a state where the peak of power consumption has generate | occur | produced by the motors M1-M4 etc., and discharges so that a capacitor voltage may not fall below a minimum value.

Supplement to the Examples. It is not necessary to charge all of the regenerative energy in the electric double layer capacitor 12, the regenerative energy may be allocated in preference to driving of another motor, and the rest may be charged in the electric double layer capacitor 12. When there is a margin in the output voltage vs of the power receiving coil 6 at the peak of the power consumption by the motors M1 to M4 or the like, it is not necessary to discharge the electric double layer capacitor 12.

In the Examples, the following effects are obtained. (1) The regenerative energy can be reliably absorbed by the electric double layer capacitor 12. For this reason, it is not necessary to generate | occur | produce surplus energy by resistance etc. and to throw it away. (2) Since the electric double layer capacitor 12 is charged by the regenerative power and surplus power from the power receiving coil 6, a return instruction with a small regenerative energy such as raising the platform to the actual load and lowering the platform to the empty load is performed. Even if this is repeated, it can charge at the time of conveyance of the goods between the traveling of a stacker crane and a raise and lower, and can reliably back up the electric power of the power receiving coil 6. (3) By estimating the regenerative energy until the next conveyance command or the next conveyance command, the empty capacity required for the electric double layer capacitor 12 can be accurately determined. For this reason, the average charge amount of the electric double layer capacitor 12 is made large and a large backup can be performed with a small capacitor. (4) By using the state of the power receiving coil, the state of the capacitor, and the predicted values of the regenerative energy, the electric double layer capacitor can be efficiently driven by simple control.

1 is a block diagram showing a power system of a mobile body of an embodiment;

2 is a block diagram of a control unit of the embodiment;

3 is a diagram schematically showing data of a capacitor control table of an embodiment;

4 is a diagram schematically illustrating charge and discharge current from an electric double layer capacitor along a table diagonal direction of FIG. 3;

FIG. 5 is a diagram schematically showing charge and discharge currents from an electric double layer capacitor along the table V-V direction of FIG. 3;

FIG. 6 is a diagram schematically showing charge and discharge current from an electric double layer capacitor along the Vi-Vi direction of the table of FIG. 3.

Description of the Related Art

2: stacker crane 4: high frequency power

5: high frequency feed line 6: power receiving coil

8: power control unit 10: electric double layer capacitor control unit

12 electric double layer capacitor 14 running control

15: lifting control unit 16: turning control unit

17: fork control unit 18: miscellaneous power

20: fan filter unit 22: main control part

24: regenerative energy prediction unit 26: capacitor control table

M1 to M4: Motor

Claims (3)

A mobile body comprising a main power source consisting of a power receiving coil receiving power from a non-contact power supply line, an auxiliary power source capable of charging and discharging, and a load operated by each of the power sources, including a plurality of motors that are both power regenerative and different in operation, A control unit for switching the connection between the auxiliary power supply, the main power supply and the load, prediction means for predicting the energy regenerated by the plurality of motors from an operation command to the moving body, and at the time of power peaking of the load from the output of the power receiving coil. Install discrimination means for determining whether or not At the power peak of the load, the load is driven by the power of both the auxiliary power supply and the main power supply, When the charge amount of the auxiliary power supply exceeds the first predetermined value except at the time of the power peak, the secondary power is discharged from the auxiliary power supply to drive the load, and the first predetermined value is changed according to the regenerative energy predicted by the prediction means, If the charging amount of the auxiliary power is less than or equal to the first predetermined value and greater than or equal to the second predetermined value, the regenerative power is generated from some of the plurality of motors while the load is driven by the power of the main power. Consume regenerative power, A moving object in which the auxiliary power is charged by the main power when the charging amount of the auxiliary power is less than the second predetermined value, and the auxiliary power is charged by regenerative power from the motor. delete delete

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