JP2015229470A - Storage battery monitoring device and control method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To appropriately store excess regenerative power and to achieve energy saving.SOLUTION: A storage battery monitoring device is supplied with power obtained by converting power from a commercial AC power source into DC and monitors a charge/discharge state of a storage battery capable of charging and discharging with respect to a DC feeding wire performing power supply to a railway vehicle. In the storage battery monitoring device, a determination section determines whether or not the storage battery is in a state of being charged by the power from the commercial AC power source on the basis of a state of the charge state with respect to the storage battery being continued for a predetermined reference period of time or more, and a dead zone correction section performs correction more increasing a dead zone in transition control to the charge state of the storage battery to a non-charge side on the basis of a voltage increase ratio of the DC feeding wire with respect to a rated voltage of the DC feeding wire when the determination section determines that the storage battery is in the state of being charged by the power from the commercial AC power source.

Description

  Embodiments described herein relate generally to a storage battery monitoring apparatus and a storage battery monitoring apparatus control method.

  In recent years, energy conservation has been an issue stemming from environmental issues and energy issues, research on energy management has been conducted in various fields, and energy conservation has also been promoted in railway businesses that use a lot of electric power.

  One effective energy-saving measure in the railway business is the effective use of regenerative power energy. For example, research is also being conducted on the use of regenerative inverters for in-station loads and the application of storage batteries.

Regenerative energy is generated when the train decelerates. When a power train is operating in the vicinity, it is accommodated in the power train, and surplus regenerative power energy (hereinafter referred to as surplus regenerative power) is not used and is lost.
Therefore, a regenerative power utilization system that stores and uses the surplus regenerative power that is lost has been studied.

  In a regenerative power utilization system, the voltage generally tends to increase when there is surplus power. Therefore, when the voltage of the DC feeder increases, it is determined that surplus regenerative power has been generated, and the storage battery is charged. On the other hand, the regenerative power utilization system conversely indicates that if the voltage of the DC feeder line is lower than the reference voltage, the excess regenerative power stored in the storage battery in order to suppress the use of commercial power is assumed to be insufficient. A discharge operation is performed to discharge power to a DC feeder.

Japanese Patent No. 3770110

  However, in the control in the above-described regenerative power utilization system, if it is determined that surplus regenerative power is generated in a state where surplus regenerative power is not generated, power from the commercial power system is stored in the storage battery. There is a fear. In particular, when the control result is bad, charging is performed when there is no load, and inefficient flow of power between the substation (rectifier) and the storage battery constituting the commercial power system in a long time zone (hereinafter referred to as cross current) Will occur.

By the way, as one of the causes of such a cross current, there is a situation where the operating voltage of the DC feeding system is set high.
This is intended to operate with the voltage close to the rated value under heavy load, but because the voltage of the DC feeder is high, there is surplus regenerative power even when there is no load. As a result, the above-described cross current may occur.
When a cross current occurs, the amount of charge (SOC: State Of Charge) of the storage battery increases, and the surplus regenerative power that should be stored cannot be stored appropriately.

  The present invention has been made in view of the above, and an object of the present invention is to provide a storage battery monitoring device and a storage battery monitoring device control method capable of appropriately storing surplus regenerative power and saving energy.

  The storage battery monitoring apparatus according to the embodiment is a storage battery monitor that monitors the charge / discharge state of a storage battery that can be charged / discharged with respect to a DC feeder for supplying power to a railway vehicle by supplying electric power from a commercial AC power source. Device.

  And a discrimination | determination part discriminate | determines whether it is a state with which the storage battery is charged with the electric power from a commercial alternating current power supply based on the state which the charge condition with respect to the storage battery continues more than predetermined reference time.

  The dead zone correction unit is configured to store the storage battery based on the rate of voltage increase of the DC feeder with respect to the rated voltage of the DC feeder when the discrimination unit determines that the storage battery is charged with power from the commercial AC power source. The dead zone in the transition control to the charged state is corrected so as to extend to the non-charge side.

FIG. 1 is an explanatory diagram of a power system of a DC feeding system according to an embodiment. FIG. 2 is a schematic block diagram of the charge / discharge control unit. FIG. 3 is a process flowchart of the cross current detection process of the monitoring device. FIG. 4 is a process flowchart of the cross current determination process and the post-process. FIG. 5 is a processing flowchart of dead zone correction processing and next day plan value data generation and storage processing. FIG. 6 is an explanatory diagram of a specific example of the next day's plan value data DPL. FIG. 7 is an explanatory diagram during normal operation in which cross current is not detected. FIG. 8 is an explanatory diagram when a cross current is generated.

Next, embodiments will be described in detail with reference to the drawings.
FIG. 1 is an explanatory diagram of a power system of a DC feeding system according to an embodiment.
The power system 10 of the DC feeding system includes an AC system 11 as a commercial AC power source, a transformer 12 that transforms the voltage of the AC system 11, and a three-phase AC current output from the transformer 12 to rectify the DC power. And a rectifier 13 for supplying to the DC feeder 14.

  Further, the power system 10 is based on the storage battery 15 that is charged / discharged with the DC feeder 14, the DC / DC converter 16 that charges / discharges the storage battery 15, and the voltage Vb of the DC feeder 14. Charge / discharge control unit 17 that outputs converter control signal Sc for controlling DC / DC converter 16, and voltage data DVb corresponding to voltage Vb of DC feeder 14, charge / discharge control unit 17 under the control of charge / discharge control unit 17. The command value data Pb and the power data PW corresponding to the output power of the DC / DC converter 16 corresponding to the command value data Pb are stored in time series, and the generated plan value data DPL for the next day is stored. The database 18 is connected to the charge / discharge control unit 17 via the communication network 19, and the database 18 is referred to for monitoring and control of the charge / discharge control unit 17. Monitoring apparatus for performing the operation of generating the next day planned data DPL to includes a (battery monitoring device) 20, a.

  In the above configuration, the electric railway vehicle (hereinafter simply referred to as a train) 21 receives power from the DC feeder 14 via the pantograph 22 and also supplies regenerative power to the DC feeder 14 via the pantograph 22. In addition, the train 21 is grounded via a wheel 23 and a track 24.

FIG. 2 is a schematic block diagram of the charge / discharge control unit.
The charge / discharge control unit 17 divides the voltage Vb of the DC feeder 14 by a preset reference rated voltage Vref to obtain a ratio of the voltage Vb to the reference rated voltage Vref, and a division result of the divider 31 1 is subtracted from the reference rated voltage Vref, and the difference between the voltage Vb and the reference rated voltage Vref is output as a percentage of the reference rated voltage Vref. If it is between -a% and + b% (dead zone: a, b> 0), the output of the subtraction result of the subtractor 32 is prohibited, and the subtraction result of the subtractor 32 is less than -a% or more than + b%. And a dead zone control unit 33 that outputs the subtraction result of the subtractor 32 in the case of.

  Further, when the subtraction result of the subtracter 32 is input via the dead zone control unit 33, the charge / discharge control unit 17 generates and outputs the command value data Pb based on the input subtraction result of the subtracter 32. A voltage adjustment control unit 34 and a DC / DC converter control unit 35 that outputs a converter control signal Sc to the DC / DC converter 16 based on the command value data Pb are provided.

Next, an outline operation of the embodiment will be described.
The rectifier 13 of the power system 10 of the DC feeder system rectifies the AC power supplied from the AC system 11 via the transformer 12 and supplies the rectified power to the DC feeder 14 as DC power.
Then, the DC power supplied to the DC feeder 14 is supplied to the train 21 as a load.

The voltage Vb of the DC feeder 14 at this time is divided by the reference rated voltage Vref set in advance by the divider 31, and the value of 1 corresponding to the reference rated voltage Vref is subtracted from the division result by the subtractor 32. A percentage value of the difference from the reference rated voltage Vref is output to the dead zone controller 33. Further, voltage data DVb corresponding to the voltage Vb of the DC feeder 14 is output to the database 18 and stored in time series.
When the subtraction result of the subtracter 32 is between −a% and + b%, the dead zone control unit 33 prohibits the output of the subtraction result of the subtractor 32 to the voltage adjustment control unit 34.

  As a result, the voltage adjustment control unit 34 and the DC / DC converter control unit 35 are in a standby state, and the storage battery 15 is charged with power from the DC feeder 14 or discharged from the storage battery 15 to the DC feeder 14. Never happen.

  On the other hand, the dead zone control unit 33 outputs the subtraction result of the subtractor 32 to the voltage adjustment control unit 34 when the subtraction result of the subtracter 32 is less than −a% or exceeds + b%.

Thereby, the voltage adjustment control part 34 adjusts the voltage of the electrical storage power of the storage battery 15 by the DC / DC converter 16, when the subtraction result of the subtractor 32 is less than -a%, and the DC feeder 14 The command value data Pb is output to the database 18 and the DC / DC converter control unit 35 so as to be supplied.
The database 18 stores the input command value data Pb in time series.

On the other hand, the DC / DC converter control unit 35 generates a converter control signal Sc based on the input command value data Pb, and outputs the converter control signal Sc to the DC / DC converter 16.
The DC / DC converter 16 adjusts (boosts) the voltage of the stored power of the storage battery 15 based on the converter control signal Sc, and shifts to a discharge state to be supplied to the DC feeder 14.

  Further, when the subtraction result of the subtractor 32 exceeds + b%, the voltage adjustment control unit 34 adjusts (steps down) the voltage Vb of the DC feeder 14 by the DC / DC converter and charges the storage battery 15. As described above, the command value data Pb is output to the database 18 and the DC / DC converter control unit 35.

Thereby, the database 18 memorize | stores the input command value data Pb in time series.
On the other hand, the DC / DC converter control unit 35 outputs a converter control signal Sc to the DC / DC converter 16, and the DC / DC converter 16 adjusts the voltage of the DC feeder 14 to charge the storage battery 15. Migrate to

Here, the operation of the monitoring device 20 will be described.
FIG. 3 is a process flowchart of the cross current detection process of the monitoring device.
In the monitoring device 20, the cross current detection process is performed at a constant evaluation period (for example, 10 minutes) every constant execution cycle (for example, every 5 minutes). More specifically, when the first cross current detection process is started at 6:00, the second cross current detection process is started at 6:05. The first cross current detection process ends at 6:10, and at the same time, the third cross current detection process starts. On the other hand, the second cross current detection process ends at 6:15, and the fourth cross current detection process starts at the same time. In this embodiment, a plurality of evaluation time zones exist in parallel. However, a plurality of cross current detection processes are performed in parallel.

  That is, in the present embodiment, by setting the execution cycle for performing the cross current detection to be shorter than the evaluation time, the current cross current detection process and the next cross current detection process are partially overlapped and performed. . As a result, even when the evaluation time is set long and the reliability of the cross current detection is improved, the cross current detection can be performed effectively in a short cycle.

First, the monitoring device 20 sets a variable Counter = 0 for counting a charging duration for detecting a continuous charging state, and sets a variable Index representing a time-series order of sampling timing of the power data PW corresponding to the command value data Pb. = 1 (step S11).
Here, the power data PW corresponds to the discharging power or charging power of the DC / DC converter 16.

  Next, the monitoring apparatus 20 stores all the variables Signal (1: 99999) for storing the evaluation result (whether or not the battery is charged) of the input power data PW, that is, the variables Signal (1) to Signal (99999). Reset to “0” (= corresponding to a non-charged state) (step S12). Here, for example, when the sampling cycle is 1 second, the evaluation result of the power data PW during 99999 seconds (= about 28 hours) from the start of sampling can be stored.

Subsequently, the monitoring device 20 reads the power data PW that has not been determined and the evaluation time zone data corresponding to the power data PW from the database 18 via the charge / discharge control unit 17 (step S13).
Subsequently, the monitoring device 20 determines whether or not the evaluation target power data PW and the evaluation time zone data corresponding to the power data PW have ended (has disappeared) (step S14).

  If it is determined in step S14 that there is still power data PW to be evaluated and evaluation time zone data corresponding to the power data PW (step S14; No), the monitoring device 20 sets the power data PW to the charged state. It is determined whether or not it corresponds (step S15).

  If it is determined in step S15 that the power data PW corresponds to the charged state (step S15; Yes), 1 is added to the variable Counter (step S19), and the process proceeds to step S20.

  In the determination of step S15, when the power data PW does not correspond to the charged state, that is, in the non-charged state (step S15; No), the monitoring device 20 determines whether the variable Counter exceeds 30; That is, it is determined whether or not the state of charge has been continued for 30 seconds or longer (= command value data Pb corresponding to the state of charge has been read continuously for 30 or more times) (step S16).

  If it is determined in step S16 that the variable counter exceeds 30 (step S16; Yes), the monitoring device 20 obtains a value obtained by subtracting the value of the variable counter from the value of the variable index at the time point. The value of A is the value of the variable index, the value of the second interval variable B, and the variable Signal (A: B) = 1.

  That is, the variables Signal (A) to Signal (B) are all set to “1” (= corresponding to the charged state) (step S17), and the process proceeds to step S18. In other words, the value of the variable counter is checked when the charging state (charging operation) is interrupted, and if the charging state has continued for 30 seconds or more, the variable corresponding to the period during which the charging state has been detected. Signal (A) to Signal (B) are all set to “1”.

If the variable counter does not exceed 30 in the determination of step S16 (step S16; No), the monitoring device 20 does not charge the storage battery 15 by the AC system 11 because the charging duration is less than 30 seconds. Assuming that charging is performed by regenerative power, the variable counter is reset and the variable counter = 0 is set (step S18).
Subsequently, the monitoring device 20 adds 1 to the variable index (step S20). That is,
index = index + 1
As a result, the process proceeds to step S13 again, and the same process is repeated thereafter.

  On the other hand, when the evaluation target power data PW and the evaluation time zone data corresponding to the power data PW have already ended (no) (step S14; Yes), the monitoring device 20 changes the variable Signal in the determination of step S14. Based on (1: index), cross current determination processing and post-processing are performed (step S21).

Here, the variable Signal will be described more specifically.
The value of the variable Signal is 0 or 1, and Signal (1) to Signal (index) are all 0 when no charge is made during the evaluation target period.

On the other hand, when charging is performed in the entire evaluation target period, Signal (1) to Signal (index) are all 1.
Therefore, during the period to be evaluated, the sum of the values of the variables Signal (1) to Signal (index) is equal to the value of the variable index at the maximum value, and the minimum value is zero.

FIG. 4 is a process flowchart of the cross current determination process and the post-process.
Therefore, a value obtained by multiplying the values of the variables Data (1) to Signal (index) by the corresponding power data PW and integrating them is set as the cross current estimated value (step S31).
More specifically, if the power data PW corresponding to each of the variables Signal (1) to Signal (index) is the power data PW1 to PWinindex, the cross current estimated value SS is as follows.
SS = Signal (1) · PW1 + Signal (2) · PW2 + ...
... + Signal (index) / PWindex

Based on the variable Signal (1: index), the monitoring device 20 performs the cross current determination based on whether or not the cross current estimated value SS exceeds a predetermined value (determination reference value) (step S32).
If it is determined in step S32 that the cross current estimated value SS is equal to or smaller than a predetermined value (step S32; No), the process proceeds to step S34 described later.

  In the determination of step S32, when the cross current estimated value SS exceeds a predetermined value, that is, when the amount of power continuously charged for a predetermined time or more exceeds the predetermined power amount (step S32; Yes), The monitoring device 20 determines that cross current has occurred. Then, correction processing of the dead zone for suppressing the cross current (the region of the electric energy that does not satisfy the charging condition) and the set value of the dead zone for each hour (for example, every hour) on the next day (plan for the next day) Value data DPL) is generated and stored in the database 18 (step S33).

Here, dead zone correction processing and generation and storage processing of planned value data DPL for the next day will be described.
FIG. 5 is a processing flowchart of dead zone correction processing and next day plan value data generation and storage processing.
First, the monitoring device 20 reads the voltage data DVb and the evaluation time zone data DTm (step S41).

  Subsequently, the reference rated voltage Vref (for example, 1.5 kV) is subtracted from the voltage Vb corresponding to the voltage data DVb and divided by the reference rated voltage Vref. u. A voltage difference value ΔVb represented by (per unit) value is calculated (step S42).

  Similarly, the same evaluation time zone corresponding to the evaluation time zone data DTm (for example, when the evaluation time is 10 minutes, 10 minutes from the evaluation start time to the evaluation end time. More specifically, for example, 6:10) ~ 6: 20), all the voltage data DVb belonging to the monitoring device 20 is p. u. Convert to value.

Subsequently, the monitoring device 20 detects p.p. in the same evaluation time zone corresponding to the evaluation time zone data DTm. u. The average value AV and standard deviation σ of the values are calculated (step S43).
And the monitoring apparatus 20 calculates the value which added standard deviation (sigma) to average value AV as a dead zone correction value (step S44). In this case, since only the voltage increase is targeted, only a positive value is used for the difference from the reference rated voltage Vref.

  Subsequently, the monitoring device 20 corrects the dead zone (= −a to + b) using the calculated dead zone correction value (step S45). More specifically, as described above, since only the voltage rise is targeted, the value b that is the upper limit value of the dead zone on the non-charging side among the values a and b that define the dead zone is a new dead zone correction value. replace.

As described above, when a cross current is detected in the monitoring device 20, the monitoring device 20 notifies the dead zone control unit 33 to that effect.
As a result, the dead zone control unit 33 absorbs the regenerative power generated in the DC feeder 14, changes the dead zone in which the charging control of the storage battery 15 is not performed into a state corresponding to the new dead zone correction, and does not perform charging more. Will be expanded.
As a result, the voltage range of the DC feeder 14 to be charged is narrowed compared to before the dead zone is expanded.

  As described above, in the monitoring device 20, since the cross current detection process is performed at a constant execution cycle, the dead zone spreads to the non-charge side each time a cross current is detected. Will be.

  When the monitoring device 20 performs the dead zone correction process for the evaluation time zone corresponding to a predetermined unit time (for example, 1 hour), for example, the average value of the dead zone values from 10:00 to 11:00. And set as the dead zone setting value for the next day in the time zone. Similarly, dead zone values for 24 hours are generated as planned value data DPL for the next day and stored in the database 18 (step S46).

FIG. 6 is an explanatory diagram of a specific example of the next day's plan value data DPL.
As shown in FIG. 6, the next day's plan value data DPL stores a dead zone setting value (the above-described value b: dead zone upper limit value) for each time zone corresponding to a unit time (1 hour in FIG. 6). ing.

For example, the value b which is the upper limit value of the dead zone from 0:00 to 1 o'clock the next day is about 3%, and the value b which is the upper limit value of the dead zone from 1 o'clock to 2 o'clock is about 2%. Yes.
Then, the upper limit value of the dead zone representing the predetermined time zone stored in time series is used as the initial value for each time zone.

  Thus, since the set value b of the dead zone for each unit time is determined based on the operation of the previous day, the charge / discharge control unit 17 actually controls the DC / DC converter 16 to control the charge / discharge of the storage battery 15. Even in this case, it is possible to suppress the occurrence of cross current.

Subsequently, the monitoring device 20 updates the evaluation time zone (step S34).
Specifically, as described above, the evaluation time zone for cross current detection is performed at a constant evaluation time zone (for example, 10 minutes) every constant execution cycle (for example, every 5 minutes). Since there are multiple evaluation time zones in parallel, a new evaluation time zone is set and updated by adding the execution period to each of the start time and end time of the last set evaluation time zone. Will be. In this case, when the designation of minute exceeds 60 minutes, the process of incrementing the hour is performed.

Here, the cross current detection will be described with a specific example.
FIG. 7 is an explanatory diagram during normal operation in which cross current is not detected.
FIG. 7A is a diagram showing a change in voltage of the DC feeder 14.

  FIG. 7B is an explanatory diagram of the output power of the DC / DC converter 16. In FIG. 7B, the positive output power is the charging power of the storage battery 15, and the negative output power is the discharging power of the storage battery 15.

  FIG. 7C is an explanatory diagram showing the values of the variables Signal (1) to Signal (index) in time series. When the charging operation continues for 30 seconds or more, the variable Signal (x) [x = 1 to index] is “1”.

  The example of FIG. 7 is a case where the cross current detection based on the voltage change of the DC feeder 14 is performed from 5:30 to 6:40, and during this 70 minutes, continuous charging for 30 seconds or more is performed. The number of times is 7 as shown in FIG.

  In this state, for each of the variables Signal (1) to Signal (index), the value obtained by multiplying and integrating the value of the corresponding power data PW is used as the cross current estimated value. Since the cross current estimated value SS is equal to or less than a predetermined value (judgment reference value), it is assumed that there is no cross current and charging by regenerative power is performed, and the monitoring device 20 updates the evaluation time zone, Similar processing is performed.

FIG. 8 is an explanatory diagram when a cross current is generated.
In FIG. 8, for the sake of easy understanding, as an extreme example of the occurrence of cross current, a case where the storage battery 15 reaches a fully charged state is taken as an example, but actually, in order to effectively recover regenerative power, the storage battery 15 Is designed not to reach full charge.

  Fig.8 (a) is a figure which shows the voltage change of the DC feeder 14 at the time of a cross current generation | occurrence | production.

  FIG. 8B is an explanatory diagram of the output power of the DC / DC converter 16. In FIG. 8B, the positive output power is the charging power of the storage battery 15, and the negative output power is the discharging power of the storage battery 15.

  FIG. 8C is an explanatory diagram showing the values of the variables Signal (1) to Signal (index) in time series. When the charging operation continues for 30 seconds or more, the variable Signal (x) [x = 1 to index] is “1”.

  FIG. 8D is a diagram showing the voltage increase rate in time series.

  The example of FIG. 8 is the case where the cross current detection based on the voltage change of the DC feeder 14 is performed from 5:30 to 6:40, similarly to the case of FIG. At that time, the battery is once fully charged, and until the time when the storage battery 15 is discharged (= 6: 18), it cannot be charged at all, and when it reaches 6:19 again, it is fully charged. Since then, the battery can no longer be charged until at least 6:30.

  In this case, the continuous charge detection based on the voltage change of the DC feeder 14 is carried out from 5:30 to 6:40, and the continuous charge of 30 seconds or more is made very much during 70 minutes. , The cross current estimated value SS obtained by multiplying each of the variables Signal (1) to Signal (index) by the value of the corresponding power data PW and integrating it exceeds a predetermined value (judgment reference value). It has become.

Therefore, for example, at the time of 5:50 when the evaluation time ends, the p. u. The average value AV is 3.25%, and the standard deviation σ is 1.63%.
As a result, the monitoring apparatus 20 replaces (corrects) 4.88%, which is a value obtained by adding the standard deviation σ = 1.63% to the average value AV = 3.25%, as the next new value b, In the dead zone control unit 33, since the dead zone is expanded to the non-charge side, the occurrence of cross current is gradually suppressed.

  As described above, according to the present embodiment, by analyzing the state of charge of the storage battery 15, particularly the state of continuation of the state of charge, using the average value AV of the voltage increase rate and the standard deviation σ, the AC system 11 (transformer) ) And the storage battery 15 can be reliably detected and the cross current can be suppressed by expanding the dead zone to the non-charge side.

  In the above description, when the amount of charging power in a predetermined continuous charging state of the storage battery exceeds the predetermined amount of charging power, a configuration for determining that the storage battery is being charged with power from a commercial AC power supply. However, when the ratio of the continuous charge state of the storage battery to the reference time exceeds the reference ratio, it is also possible to adopt a configuration for determining that the storage battery is being charged with power from the commercial AC power supply. is there.

  The storage battery monitoring device of the present embodiment includes a control device such as a CPU, a storage device such as a ROM (Read Only Memory) and a RAM, an external storage device such as an HDD and a CD drive device, a display device such as a display device, It has an input device such as a keyboard and a mouse, and has a hardware configuration using a normal computer.

  The control program executed by the storage battery monitoring apparatus of the present embodiment is an installable or executable file, and is a computer such as a CD-ROM, flexible disk (FD), CD-R, DVD (Digital Versatile Disk). Recorded on a readable recording medium.

  Moreover, you may comprise so that the control program run with the storage battery monitoring apparatus of this embodiment may be provided by storing on a computer connected to networks, such as the internet, and downloading via a network. Further, the control program executed by the power storage monitoring device of the present embodiment may be provided or distributed via a network such as the Internet.

  Moreover, you may comprise so that the control program of the storage battery monitoring apparatus of this embodiment may be previously incorporated in ROM etc. and provided. In this case, the control program incorporated in the ROM or the like is based on the charge / discharge state of the storage battery capable of charging / discharging the DC feeder for supplying power to the railway vehicle by supplying power from the commercial AC power source to DC. A control program for controlling a storage battery monitoring device to be monitored by a computer, and when the ratio of the continuous charge state of the storage battery to a reference time exceeds a reference ratio, the storage battery is charged with power from the commercial AC power supply. When the storage battery is determined to be in a state of being charged by the electric power from the commercial AC power source, the storage battery is connected to the DC feeder based on the voltage of the DC feeder. The computer is operated so as to further widen the dead zone in the control of transition to the charged state.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 10 Power system 11 AC system 12 Transformer 13 Rectifier 14 DC feeder 15 Storage battery 16 DC / DC converter 17 Charge / discharge control part 18 Database 19 Communication network 20 Monitoring apparatus 21 Train 31 Divider 32 Subtractor 33 Dead band control part 34 Voltage adjustment Control unit 35 DC / DC converter control unit Pb command value data Sc converter control signal

Claims (6)

A storage battery monitoring device that monitors the charge / discharge state of a storage battery that can be charged / discharged with respect to a DC feeder that supplies power from a commercial AC power source after being converted to DC,
A determination unit that determines whether or not the storage battery is being charged with power from the commercial AC power source based on a state in which the charging state for the storage battery continues for a predetermined reference time or more;
When the determination unit determines that the storage battery is in a state of being charged with electric power from the commercial AC power source, the storage battery is based on the voltage increase rate of the DC feeder with respect to the rated voltage of the DC feeder. A dead zone correction unit that performs correction to expand the dead zone in the control of transition to the charging state of the battery to the non-charging side;
A storage battery monitoring device. The dead zone correction unit performs the correction based on an average value and a standard deviation of the voltage increase rate within a predetermined evaluation time.
The storage battery monitoring apparatus according to claim 1. In the correction, the dead zone correction unit sets the average value of the voltage increase rate and the sum of the standard deviation as a new upper limit value of the dead zone,
The storage battery monitoring device according to claim 2. The upper limit value representing a predetermined time zone is stored in time series, and used as an initial value for each time zone,
The storage battery monitoring device according to any one of claims 1 to 3. The determination unit is configured to charge the storage battery with electric power from the commercial AC power source when an accumulated power amount in a state where the charging state of the storage battery continues for a predetermined reference time or more exceeds a predetermined value. Determine that it is in a state,
The storage battery monitoring apparatus according to any one of claims 1 to 4. A method for controlling a storage battery monitoring device that monitors the charge / discharge state of a storage battery that can be charged / discharged with respect to a DC feeder for supplying power to a railway vehicle by supplying electric power from a commercial AC power source,
Determining whether the storage battery is in a state of being charged with power from the commercial AC power supply based on a state in which the state of charge of the storage battery continues for a predetermined reference time or more;
When it is determined that the storage battery is being charged by power from the commercial AC power supply, the storage battery is charged based on the voltage increase rate of the DC feeder with respect to the rated voltage of the DC feeder. The process of correcting the dead zone in the transition control of the non-charge side more,
A method for controlling a storage battery monitoring device comprising: