KR20110073091A - Battery power control device according to working mode in hybrid industrial vehicle - Google Patents

Abstract

PURPOSE: A battery power control device of the hybrid industrial vehicle using battery and ultracapacitor as a power supply on the basis of the work mode is provided to advantageously control a battery power with the corresponding battery output value to the relevant mode in case of changing a work mode. CONSTITUTION: The battery power control device of the hybrid industrial vehicle on the basis of the work mode includes an electricity supply part, which is composed of a battery and an ultracapacitor and supplies electricity; and a controller, which controls a battery output with a predetermined battery output value corresponded to a selected work mode at an initial work mode selection, calculates a differential of the battery output control value corresponding to the previous work mode from the battery output control value corresponding to the changed work mode, and controls the battery output with revised battery output control value by adding the calculated a compensation value to the battery output control value. In a standard operation pattern of each for each mode corresponding to each work vehicle, the battery output control value at each work mode is a mean of the work load. The controller more includes a DC/DC converter changing the direct current (DC) voltage outputted from the battery to the DC voltage controlled by the controller. The controller controls the DC value to change in the DC/DC converter to control the battery output with a goal control value of the battery.

Description

Battery power control device according to work mode in hybrid industrial vehicle {POWER CONTROL APPARATUS ACCORDING TO WORK MODE IN HYBRID INDUSTRIAL VEHICLE}

The present invention relates to a battery power control apparatus for a hybrid industrial vehicle, and more particularly, to an apparatus for quickly controlling the battery output to a battery output corresponding to the changed working mode when the working mode is changed in a hybrid industrial vehicle using dual power source. will be.

Recently, with the rapid increase in oil prices, the research on the hybrid type industrial vehicle which has saved the surplus power of the engine in the electric energy storage device and improved the fuel efficiency by supplying the insufficient power of the engine from the electric energy storage device has been actively conducted. .

The electric energy storage device of the hybrid industrial vehicle is composed of a battery and an ultracapacitor to control power according to the characteristics of each storage device to maximize energy efficiency.

Batteries have a higher storage energy density than ultracapacitors, but output densities are larger than ultracapacitors.

Accordingly, frequently generated or large power supplies power from ultracapacitors, while small power and large amounts of energy needed in the long term are powering batteries.

On the other hand, when the work mode is changed from a heavy load job to a small job in a hybrid industrial vehicle using a dual power source, the battery output may be adjusted for a low load job even for an initial battery output set for a heavy load job. It should be adjusted. That is, in order to prevent a decrease in energy efficiency and work efficiency, a technology development related to a change in output control of power sources is required according to a change in a work mode.

Accordingly, an object of the present invention is to provide a control device capable of preventing a decrease in energy efficiency and work efficiency when a work mode is changed in a hybrid industrial vehicle using a dual power source.

The battery power control apparatus for a hybrid industrial vehicle according to the present invention for achieving the above-mentioned includes a battery and an ultra capacitor, a power providing unit for providing power, and a battery preset in response to the selected work mode when the initial work mode is selected The battery output is controlled using an output control value, a difference between the battery output control value corresponding to the previous work mode is calculated from the battery output control value corresponding to the changed work mode when the work mode is changed, and the current battery output control value is calculated. And a controller configured to control the output of the battery using the compensated battery output control value by applying a compensation value.

In addition, according to an example of the present invention, the battery output control value for each work mode may be an average value of workloads in a standard work pattern of a corresponding work vehicle for each mode.

In addition, the battery power control apparatus of a hybrid industrial vehicle according to an embodiment of the present invention further includes a DC / DC converter for converting a direct current (DC) voltage output from the battery into a DC voltage controlled by the control unit, the control unit The controller may control a DC value to be converted in the DC / DC converter so that the battery output is adjusted to a target control value of the battery.

In addition, according to an example of the present invention, the control unit calculates a workload average value for a predetermined time, and if the ultra-capacitor voltage value is out of a preset allowable voltage range, corrects the load value preset by the current average workload average value. And control the voltage of the ultracapacitor to fall within the allowable voltage range, and control the output of the battery using the corrected workload as a target control value of the battery.

In addition, according to an example of the present invention, the control unit calculates a workload average value by measuring a workload at a predetermined measurement period for a predetermined time, and the allowable voltage range is a minimum allowable voltage value as a lower limit and an upper limit to a maximum allowable voltage value. If the ultra capacitor voltage value is greater than or equal to the maximum allowable voltage value, the control unit performs negative correction by a load value preset to the current average workload average value, and if it is less than or equal to the minimum allowable voltage value, the current average workload average value. The amount of correction is performed by a predetermined load value.

According to the present invention described above, there is an advantage that the battery output control value corresponding to the mode can be controlled immediately when the operation mode is changed.

In addition, after controlling the battery output control value appropriate to the operation mode, there is an advantage that can be more accurately reflected in the battery output control by controlling the battery output according to the actual vehicle load.

In addition to changing the workload, the battery power is controlled by taking into account the voltage of the ultracapacitor, ensuring that the voltage of the ultracapacitor does not exceed the maximum and minimum tolerances.

DETAILED DESCRIPTION A detailed description of preferred embodiments of the present invention will now be described with reference to the accompanying drawings. It should be noted that the same components in the figures represent the same numerals wherever possible. Specific details are set forth in the following description, which is provided to provide a more thorough understanding of the present invention. In describing the present invention, when it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

In the hybrid industrial vehicle according to the present invention, the mode pattern is divided into a high mode, a standard mode, and an economy mode according to the size of the work load, and the operator operates in accordance with the working characteristics. After you select, you can work. As described above, in the embodiment of the present invention, three modes will be described as examples, but it should be noted that the working modes may be classified in more detail and have a larger number of modes.

1 is a configuration of a battery power control apparatus according to a work mode in a hybrid industrial vehicle according to an embodiment of the present invention.

Referring to FIG. 1, a battery power control apparatus according to the present invention includes a control unit 100, a battery 102, a direct current / direct current (DC / DC) converter 104, an inverter 106, a motor 108, An ultracapacitor 110 and a vehicle operator 112 are included.

When DC power output from the battery 102 and the ultra capacitor 110 is applied to the inverter 106, the inverter 106 converts the applied DC power into AC power and supplies the motor 108 to the motor 108. ).

In this case, in the battery power control apparatus having the dual power supply structure as shown in FIG. 1, the battery 102 outputs a constant power as much as possible, and when the workload changes rapidly, the power of the ultra capacitor 110 is used. .

The battery 102 has a large internal loss due to the internal resistance of the battery when the output fluctuation of the battery is severe, and adversely affects the life of the battery. Continuous use time) and long life.

Accordingly, when the workload changes drastically, the power of the ultracapacitor 110 is additionally used.

Therefore, there is a need to adjust the output of the battery 102 through the DC / DC converter 104 control to reflect the working pattern.

In the present invention, the battery output control value for each operation mode is preset. Here, the preset battery output control value for each work mode is an average value of the workloads in the standard work pattern of the corresponding work vehicle for each mode.

Also, the battery output control value corresponding to the work mode set when the initial work mode is set is controlled as the initial target control value of the battery. Subsequently, when the work mode is changed, the difference between the battery output control value corresponding to the changed work mode and the battery output control value corresponding to the current work mode is compensated to the current battery output control value to compensate the battery output control value compensated for. Control by value.

To this end, the controller 100 controls the output of the battery 102 to a preset battery output control value corresponding to the selected work mode when there is an initial work mode selection through the vehicle control unit 112.

In addition, the controller 100 calculates a difference between the battery output control value corresponding to the previous work mode from the battery output control value corresponding to the changed work mode when there is a work mode change through the vehicle manipulation unit 112.

Thereafter, the controller 100 controls the output of the battery to the compensated battery output control value by adding a compensation value calculated to the previous battery output control value.

After controlling the battery output control value corresponding to the mode immediately when the work mode is changed, the controller 100 can more accurately reflect the workload to the battery output control by controlling the battery output according to the actual vehicle load. Will be.

Next, a process of controlling the battery power according to the working mode according to the embodiment of the present invention will now be described with reference to the flowchart of FIG. 2.

First, after checking the currently set work mode (S200), it is checked whether the previously set work mode exists (S201).

If the previously set work mode does not exist, that is, if the initial work mode is the initial vehicle start, the output control value of the battery is set to the battery output control value corresponding to the currently set work mode (S205).

However, if the previously set work mode exists, it is checked whether the currently set work mode is the same as the immediately set work mode (S202).

If the work mode set immediately before the result of the check is the same as the currently set work mode, the current battery output control value will be set to be the same as the previous battery output control value (S203).

However, if the work mode set immediately before the result of the S202 inspection is not the same as the currently set work mode, that is, the work mode is changed.

The difference between the battery output control value corresponding to the previous working mode is calculated from the battery output control value corresponding to the changed working mode, and the compensated battery output control value is added to the previous battery output control value and the compensated battery output control value is output of the current battery. Set to the control value (S204).

Subsequently, the battery output control value is controlled according to the vehicle load while controlling the battery output using the current battery output control value set in S203, S204, and S205 (S206). After the battery output control in step S206 to control the battery output according to the actual workload to perform a more precise battery output control.

In this case, when controlling the battery output in step S206, the battery output may be controlled only according to the load change, or in another embodiment, the battery output may be controlled in consideration of the voltage of the ultra capacitor 110. An operation for controlling the battery output in consideration of the voltage of the ultra capacitor will be described in detail with reference to FIGS. 4 to 6 below.

Thereafter, when the operation ends, the operation is terminated. Otherwise, the operation proceeds to step S200 to continuously control the power of the battery according to the operation mode (S207).

As described above, the battery power control flow according to the operation mode will be described with reference to the graph of FIG. 3.

For example, the average value of the standard work pattern load in the high mode is Pbat_h, and the average value of the standard work pattern load in the Standard Mode is Pbat_s and the average value of the standard work pattern load in the Economy Mode. Assume Pbat_e. In addition, when the previous work mode does not exist, that is, when the driver selects the work mode as the high mode when the vehicle is initially started, the output control value of the battery is set to Pbat_h and controlled by the set Pbat_h.

As such, after controlling the vehicle battery to the initial battery output control value, the control unit 100 changes and controls the output control value of the battery according to the workload.

Subsequently, if the driver changes the working mode to the economy mode due to a change in the working environment or the like during the work, the control unit 100 may change the previous work mode to the high mode and the current work mode to the economy mode. Compensate the battery output control value using the compensation value calculated at the time of mode change by calculating the compensation value according to the work mode change.

In this case, the compensation value may be calculated as in Equation 1 below.

Compensation value = Battery output control value corresponding to the changed working mode-Battery output control value corresponding to the previous working mode

For example, if the previous work mode is the high mode and the currently changed work mode is the economy mode as in the above assumption, the compensation value will be calculated as shown in Equation 2 below.

Compensation value = Pbat_e-Pbat_h

The battery output control value compensated using the compensation value calculated as in Equation 2 may be calculated as in Equation 3 below.

Pbat corresponding to the current working mode = Battery output control value corresponding to the previous working mode + (Pbat_e-Pbat_h)

At this time, since Pbat_e <Pbat_h, the compensation value (Pbat_e-Pbat_h) has a negative value, that is, as the driver changes the working mode from the high mode to the economy mode, the output of the battery can be immediately lowered.

In other words, when changing from the high mode to the economy mode, the battery output is immediately lowered as shown in 301 by applying a compensation value such as 310 to the current battery output control value. If the battery output control according to the operation mode is not performed as in the present invention, after a predetermined time elapses from the change time point such as 300, the battery output control value suitable for the change mode will be lowered.

At this time, since the compensation value is calculated in advance from the standard work pattern, the appropriate compensation can be achieved.

As such, when the operation mode is changed immediately after controlling the battery output control value corresponding to the mode, the battery output can be more accurately reflected in the battery output control by controlling the battery output according to the actual vehicle load.

In this case, the battery output may be controlled by the battery output control value corresponding to the working mode, and then the battery output may be controlled only according to the load change. Alternatively, the battery output may be controlled in consideration of the voltage of the ultra capacitor 110. have.

As described above, an operation for controlling the battery output in consideration of the voltage of the ultracapacitor will be described with reference to FIGS. 1 and 4 to 6.

First, referring to FIG. 1, the controller 100 reads a workload of a vehicle at a predetermined cycle and calculates a workload average value for a predetermined time. At this time, it is preferable that the number of total workload measurement values is set according to the repetition period of the standard load pattern of the vehicle when calculating the average value.

In the workload measurement, the controller 100 reads an output value of the ultracapacitor 110 applied to the inverter 106 to measure a load of a current job.

Then, the workload average value calculation method will be described with reference to FIG. 2.

If the workload measurement cycle is t and the constant time for calculating the average is T, the total number of measured samples N of the workload is T / t. At this time, the measurement period t and the time T for calculating the average are appropriately set according to the load characteristics of the work vehicle. If the load fluctuates very rapidly, t should be kept small, and T would be appropriate if one cycle is selected as the standard work pattern of the working vehicle to which this control is applied.

For example, if t is set to 0.1 second and T is assumed to be 100 seconds, the workload sample number N is 1000.

As shown in FIG. 4, an average is calculated as 400 for 1000 workload values Pload_1, Pload_2,..., And Pload_1000 measured at 0.1 second intervals.

Then, when the new 1001th workload is measured, as shown in 401, the oldest workload value Pload_1 is discarded and the new workload value Pload_1001 is used to calculate an average of 1000 samples.

When the average value of the workload is calculated in the same manner as in FIG. 4, the control unit 100 controls the average value of the calculated workload as the output target value of the battery 102. At the same time, when the voltage of the ultracapacitor 110 reaches an upper limit value or a lower limit value, the controller 100 performs a correction by a preset correction value to the average value of the workload. By correcting the average value of the workload as described above to reduce the frequency of the voltage of the ultra-capacitor 110 reaches the upper limit or the lower limit.

Referring back to FIG. 1, the ultracapacitor 110 selects and applies an appropriate voltage range and an appropriate capacity according to vehicle load characteristics. However, since the load pattern of the vehicle examined in the capacity selection and the workload pattern of the actual vehicle cannot be the same, the voltage of the ultracapacitor 110 may approach the upper or lower limit during the operation of the actual vehicle.

Ultracapacitor 110 voltage range is based on the upper and lower limits of the hardware specifications, the upper limit is set to the maximum allowable voltage value lower than the maximum voltage specification in consideration of safety, the lower limit is the maximum load of the work vehicle It is desirable to set the possible output to the lowest allowable voltage value that can be generated.

If the voltage of the ultracapacitor 110 reaches a preset maximum allowable voltage value or the minimum allowable voltage value during the load operation, the controller 100 performs a control to correct the workload average value to perform the ultracapacitor 110. Control the voltage not to exceed the allowable range. In this way, the frequency at which the ultracapacitor 110 voltage reaches a maximum / minimum allowable voltage value may be reduced.

As described above, in the present invention, the battery power is controlled by following the change of the workload, and controlling the battery power in consideration of the voltage of the ultracapacitor 110.

As such, the battery power control flow considering the voltage of the ultracapacitor will be described with reference to the graph of FIG. 5.

First, 504 is a workload average value of the sample number N, and 506 is a value in which the correction value is reflected in the workload average value of the sample number N. FIG. In addition, 510 is the voltage value Vcap of the ultracapacitor in the case where the value of the correction value is reflected in the workload average value of the sample number N as the target control value of the battery output control value Pbat, and 512 is the number of samples. The voltage value Vcap of the ultracapacitor in the case where the workload average value of N is set as the target control value of the battery output control value Pbat.

If the voltage Vcap of the ultracapacitor 110 becomes the preset maximum allowable voltage value Vcap_max as A at the point 500 having the average load value at the nth measurement point, at the n + 1th measurement point When calculating the average load value, a correction is performed to reflect the preset correction value in the calculated workload average value.

In this case, the average load value correction at the n + 1 th measurement time may be performed as in Equation 4 below.

(Average of Pload @ step = n + 1)-Pcomp

At this time, “Average of Pload @ step = n + 1” is an average load value calculated at the n + 1 th measurement time point, and “Pcomp” is a preset correction value. Here, the preset correction value may be a function consisting of a system variable or an appropriate fixed value.

Thereafter, if the voltage Vcap of the ultracapacitor 110 becomes the preset maximum allowable voltage value Vcap_max as shown in B at the point 501 having the average load value at a predetermined measurement time point, the preset workload average value is set in advance. Perform a correction that reflects the correction. Then, as shown in 501, the load value drops by a preset correction value, and the voltage value of the ultracapacitor 110 also falls below the maximum allowable voltage value.

In the embodiment of FIG. 5, the case where the correction is performed to the average workload value when the voltage of the ultracapacitor 110 reaches the maximum allowable voltage value has been described.

On the contrary, when the voltage of the ultracapacitor 110 reaches a preset limit minimum voltage value, positive correction is performed to the workload average value so that the voltage of the ultracapacitor 110 is included in the allowable voltage range.

6 is a flowchart illustrating a process of controlling power of a battery in consideration of a voltage of an ultracapacitor according to an embodiment of the present invention.

The average workload value is calculated for a predetermined time (S600).

Thereafter, it is checked whether the ultracapacitor voltage value is greater than or equal to the maximum allowable voltage value or less than the minimum allowable voltage value (S602 and S610). That is, it is to check whether the ultracapacitor voltage value is out of the preset allowable range.

If the ultra-capacitor voltage value is greater than or equal to the maximum allowable voltage value, negative correction is performed to the current workload average value (S604). If the ultra-capacitor voltage value is less than or equal to the minimum allowable voltage value, positive correction is performed to the current workload average value. (S612)

However, if the ultra capacitor voltage value is within the allowable range, the process proceeds to step S606 without correction.

On the other hand, after correcting the workload value in steps S604 and S612 and proceeds to step S606, the battery output is adjusted to the target control value of the battery 102, the corrected workload value. At this time, the battery output will be adjusted by the control unit 100 through the DC / DC converter as mentioned in the description of FIG.

Thereafter, when the operation ends, the operation is terminated, otherwise, the operation proceeds to step S600 to continuously control the power of the battery in consideration of the voltage of the ultracapacitor 110.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, those skilled in the art to which the present invention pertains may implement the present invention in other specific forms without changing the technical spirit or essential features thereof. I can understand that.

Therefore, since the embodiments described above are provided to completely inform the scope of the invention to those skilled in the art, it should be understood that they are exemplary in all respects and not limited. The invention is only defined by the scope of the claims.

1 is a configuration diagram of a battery power control apparatus according to a working mode in a hybrid industrial vehicle according to an embodiment of the present invention;

2 is a flowchart illustrating a process of controlling battery power according to a work mode according to an embodiment of the present invention;

3 is a graph illustrating battery power control according to a work mode according to an embodiment of the present disclosure;

4 is an exemplary view showing a method for calculating an average value of a workload according to another embodiment of the present invention;

5 is a graph illustrating battery power control considering voltage of an ultracapacitor according to another embodiment of the present invention;

6 is a flowchart illustrating a process of controlling power of a battery in consideration of a voltage of an ultracapacitor according to another embodiment of the present invention.

DESCRIPTION OF THE REFERENCE NUMERALS OF THE DRAWINGS

100: control unit 102: battery

104: DC / DC converter 106: inverter

108: motor 110: ultracapacitor

112: vehicle operation unit 120: power providing unit

Claims (5)

A power providing unit including a battery and an ultracapacitor and providing power; When the initial work mode is selected, the battery output is controlled by a preset battery output control value corresponding to the selected work mode, and when the work mode is changed, the battery output control value corresponding to the previous work mode by the battery output control value corresponding to the changed work mode. And controlling the output of the battery with the compensated battery output control value by calculating a difference of the difference and adding a compensation value calculated to the current battery output control value. Device. The battery output control value for each work mode is: Battery power control device according to the work mode in the hybrid industrial vehicle, characterized in that the average value of the workload in the standard work pattern of the corresponding work vehicle for each mode. The method of claim 1, And a DC / DC converter for converting a DC voltage output from the battery into a DC voltage controlled by the controller. The control unit controls the battery power of the hybrid industrial vehicle, characterized in that for adjusting the DC value to be converted in the DC / DC converter so that the battery output is adjusted to the target control value of the battery. The method according to any one of claims 1 to 3, wherein the control unit, The workload average value is calculated for a predetermined time, and when the ultra capacitor voltage value is out of the preset allowable voltage range, the voltage of the ultra capacitor is within the allowable voltage range by correcting by the load value preset to the current average workload average value. And controlling the output of the battery by using the corrected workload value as a target control value of the battery. The method of claim 4, wherein the control unit, Calculate the workload average value by measuring the workload every preset measurement period for a predetermined time period,  The allowable voltage range is a range in which the minimum allowable voltage value is the lower limit and the maximum allowable voltage value is the upper limit, The control unit, If the ultra-capacitor voltage value is greater than or equal to the maximum allowable voltage value, negative correction is performed by a load value preset to the current average workload average value, and when the ultra-capacitor voltage value is less than or equal to the minimum allowable voltage value, positive correction is performed by the load value preset to the current average workload average value. Battery power control apparatus for a hybrid industrial vehicle, characterized in that to carry out.

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