Railway system, on-board device and server for railway system, and charging control method for storage battery

Abstract

In order to provide technology for reducing an increase in the temperature of a storage battery mounted on a vehicle and deterioration of the storage battery during charging of the storage battery, while minimizing the effects of power shortages or worsening power costs and the like on train operations, a railway system including an on-board device mounted on a railway vehicle and a server that transmits and receives data to and from the on-board device is provided. The on-board device transmits storage battery information indicating the state of a storage battery mounted on the railway vehicle to the server. The server predicts a stay time of the railway vehicle and the required charging amount of the storage battery in an electrified section, in which the railway vehicle is traveling, on the basis of operation information indicating the operation state of the railway vehicle or an operation diagram of the railway vehicle, upper and lower limit charging rates of the storage battery, and the storage battery information received from the on-board device, determines the charging speed of the storage battery in the electrified section from the predicted stay time and the required charge amount, and transmits the determined charging speed to the on-board device.

Description

Railway system, on-board device and server of railway system, and battery charge control method

[0001] The present invention relates to a railway system for a railway vehicle equipped with a storage battery, an on-board device and server for the railway system, and a method for controlling charging of the storage battery.

[0002] In recent years, against the backdrop of environmental issues such as global warming, there has been an active movement to promote energy conservation in various industrial sectors. This energy conservation is also being promoted in the transportation system sector, and even railways, which are more energy efficient than other transportation systems such as automobiles and aircraft, are being called upon to further reduce their power consumption. Under these circumstances, research and development of vehicles equipped with storage batteries, such as battery-powered electric trains, which charge storage batteries in electrified sections (overhead line sections) and run solely on storage batteries in non-electrified sections (non-overhead line sections), has been widely conducted and has been put into practical use.

[0003] Lithium-ion batteries and other storage batteries used in storage battery systems for railway vehicles generate heat when they are charged and discharged. To protect the safety of the battery and prevent deterioration, it is therefore necessary to limit the charging and discharging current so that it does not deviate from the battery's usable temperature range (e.g., -30 to 60°C).

[0004] On the other hand, limiting the charge and discharge current raises the risk of running out of power while the train is in an electrified section because it is unable to store enough electricity to travel to the next electrified section, or of the battery not being able to fully absorb regenerative power during deceleration, resulting in a deterioration in power efficiency.

[0005] Furthermore, even on lines that handle multiple trains, in electrified sections where the charging equipment has a small capacity and can only charge one vehicle at a time, if more vehicles than usual are stopped at the same time due to a schedule disruption, there is a risk of service delays due to overlapping charging times.

[0006] Patent Document 1 discloses a method for predicting a temperature rise of a storage battery based on the storage battery temperature and the amount of charge and discharge current, and using the predicted temperature rise result to select one upper limit charge and discharge current value from multiple upper limit charge and discharge current values ​​to limit the charge and discharge current so that the upper limit temperature of the storage battery is not exceeded.

[0007] JP 2018-170904 A

[0008] The technology described in Patent Document 1 is a method of controlling current based on real-time battery temperature and charge / discharge current to prevent temperature deviations. Therefore, Patent Document 1 does not anticipate or mention a technology for minimizing the impact on operation by changing the current control plan immediately before or during operation while taking into account battery power shortages and deterioration of power costs during operation, even when an operation plan has been decided.

[0009] The object of the present invention is to provide a technology that minimizes the impact of power shortages and deterioration of power costs on train operations, while reducing the increase in battery temperature and battery deterioration when charging batteries installed in vehicles.

[0010] In order to solve the above problems, one representative railway system according to the present invention comprises an on-board device mounted on a railway vehicle and a server that transmits and receives data to and from the on-board device, the on-board device transmits battery information indicating the status of the batteries mounted on the railway vehicle to the server, the server predicts the duration of the railway vehicle's stay in the electrified section along which the railway vehicle travels and the required amount of charge for the batteries based on operation information indicating the operating status of the railway vehicle or the railway vehicle's timetable, the upper and lower limit charge rates of the batteries, and the battery information received from the on-board device, determines the charging rate for the batteries in the electrified section from the predicted duration of the stay and the required amount of charge, and transmits the determined charging rate to the on-board device.

[0011] According to the present invention, by minimizing the charging speed in electrified sections, it is possible to minimize the impact on operation, such as power shortages and deterioration of power efficiency, while suppressing increases in battery temperature and battery deterioration during charging. Furthermore, by managing operation information, battery information, and upper and lower limit charging rates on a server outside the vehicle, it is possible to update the charging speed in the event of schedule changes, battery deterioration, or an emergency. Problems, configurations, and effects other than those described above will become clear from the description of the following embodiments of the invention.

[0012] 1 is a block diagram showing an example of the configuration of a battery electric train drive system for railway vehicles according to an embodiment of the present invention. FIG. 2 is a block diagram showing an example of the configuration of a battery system according to an embodiment of the present invention. FIG. 3 is a block diagram showing an example of the configuration of a charging rate determination system in a server. FIG. 4 is a flowchart showing a processing aspect of a charging rate determination method. FIG. 5 is a diagram showing an example of a case where the charging rate is varied for each electrified section (for each charging facility) and reflected in a railway operation plan and a storage battery charge / discharge control plan. FIG. 6 is a diagram showing another example of a case where the charging rate is varied for each electrified section (for each charging facility) and reflected in a railway operation plan and a storage battery charge / discharge control plan. FIG. 7 is a diagram showing three examples of a case where the lower limit charging rate or charging rate is varied and reflected in a railway operation plan and a storage battery charge / discharge control plan when a timetable disruption occurs. FIG. 8 is a diagram showing two examples of a case where the charging rate is varied and reflected in a railway operation plan and a storage battery charge / discharge control plan when a timetable disruption occurs and more vehicles than usual are staying in an electrified section with a small charging facility capacity.

[0013] Hereinafter, examples will be described as modes for carrying out the present invention with reference to the drawings. Note that the present invention is not limited to these examples. In addition, in the description of the drawings, the same parts are designated by the same reference numerals.

[0014] 1 is a block diagram showing an example of the configuration of a battery electric railcar traction system 1 for railway vehicles according to an embodiment of the present invention. In the figure, solid lines indicate power transmission paths, double lines indicate torque transmission paths, and dotted lines indicate transmission paths for information such as control signals and sensor values. A vehicle equipped with the battery electric railcar traction system 1 runs on overhead power and charges its storage battery in electrified sections, and runs on battery power in non-electrified sections.

[0015] The battery electric train drive system 1 is composed of a pantograph 2 that contacts the overhead wire 14, a converter 5 that converts the power supplied from the overhead wire 14 into the required DC power, a motor inverter 6 that converts the DC power into AC power, a motor 7 that drives the railway vehicle, a reducer 8 that reduces the output of the motor 7 and transmits it to the wheel set 9, an auxiliary inverter 10, auxiliary equipment 11 used for services such as vehicle lighting and air conditioning, a battery system 20, a driver's cab 12 that has a display and generates driving commands in response to the driver's notch operation, etc., a vehicle control device 13 that generates control commands for the converter 5, the motor inverter 6, and the auxiliary inverter 10 based on the driving commands transmitted from the driver's cab 12 and the state of the battery system 20, and a data transmission / reception device 60 that wirelessly transmits and receives data and signals from the battery system 20 and the vehicle control device 13 to and from a server 70 outside the vehicle.

[0016] The pantograph 2 is an electric switch that moves up and down, and when it rises and comes into contact with the overhead wire 14, it supplies DC or AC power from the overhead wire 14 to the converter 5. As a battery-powered train, in the section where the pantograph 2 is in contact with the overhead wire 14, the train runs on power from the overhead wire and charges the battery, and in the section where the pantograph 2 is not in contact with the overhead wire 14, it uses power from the battery.

[0017] The converter 5 receives DC power or AC power supplied via the pantograph 2 as input, converts it into DC power corresponding to the commanded amount of power, and outputs it.

[0018] The motor inverter 6 converts the DC power supplied via the converter 5 into three-phase AC power to drive the motor 7. The motor 7 receives the three-phase AC power output by the motor inverter 6, converts it into axle torque, and outputs it. The speed reducer 8 reduces the rotational speed of the motor 7 by combining gears with different numbers of teeth, and the axle torque thus amplified drives the wheel set 9 to accelerate or decelerate the vehicle. In addition, a speed generator (not shown) for measuring vehicle speed is attached to the wheel set 9.

[0019] The auxiliary inverter 10 converts the DC power between the converter 5 and the motor inverter 6 into three-phase AC power and outputs it to the auxiliary 11. The auxiliary 11 is a service device such as lighting or an air conditioning device for the vehicle, and operates on the power supplied from the auxiliary inverter 10.

[0020] The driver's cab 12 is equipped with at least a display (not shown) that displays the time, vehicle speed, battery information, etc., and an input device (not shown) through which the driver inputs driving commands, etc., into the vehicle control device 13. Furthermore, the driver's cab 12 may be provided with a means for informing the driver that the required amount of charge has been charged before the next electrified section. For example, a monitor may be installed that displays the energy required before the next electrified section, the target charging rate for each electrified section, and the predicted charging rate during charging. In addition, the remaining time until the target charging rate and the remaining time until departure may be displayed. This allows the driver to operate without worrying that the target charging rate will not be reached before departure. Note that the electrified section is an example of a location where charging is possible, and may be interpreted as a charging station, etc.

[0021] The storage battery system 20 includes a storage battery as a device for storing energy for driving the railway vehicle. The storage battery is charged with DC power output from the converter 5 and discharged to the motor inverter 6 and the auxiliary inverter 10. When the vehicle is applying regenerative braking, the storage battery is charged with DC power output from the motor inverter 6. The storage battery control device 201 of the storage battery system 20 measures the state of the storage battery and acquires storage battery information indicating the state of the storage battery, etc., and calculates the charging rate and allowable current (current that can be safely passed), and communicates the required information with the vehicle control device 13.

[0022] The vehicle control device 13 outputs control signals to the converter 5, the motor inverter 6, and the auxiliary inverter 10 based on the operation command, the state of the battery system 20, the state of the pantograph 2, etc., and controls the entire battery electric train drive system 1. The vehicle control device 13 also communicates with the data transmission / reception device 60 to transmit and receive necessary data. The vehicle control device 13 also has a charging speed recording unit 131 that records charging speed data and upper limit charging speeds for each electrified section, and controls the charging speed of the battery system 20 based on these values. Note that, in order to determine whether the vehicle is located in an electrified section, the vehicle control device 13 may receive, for example, a station code (a number assigned to a station) as an electrified section presence determination signal from an electrified section presence determination means (not shown). Alternatively, presence in an electrified section may be determined based on a train schedule.

[0023] The data transmitter / receiver 60 receives data from the vehicle control device 13 and the battery box control board 211 ( FIG. 2 ) inside the battery system 20, transmits the data wirelessly to a server 70 outside the vehicle, and receives control commands, display contents on the driver's cab 12, charging speed, etc. from the server 70. Transmission to the server 70 may be via proximity wireless (wireless LAN) at the station, via an LTE line, or the like. Although the data transmitter / receiver 60 is shown as an independent device in FIG. 1 , it may be included as one function of the battery system 20, the vehicle control device 13, or a TCMS (Train Control Management System) (not shown).

[0024] The data transmitted from the data transmission / reception device 60 includes, for example, operation information indicating the operating status of the vehicle and storage battery information indicating the status of the storage battery. Here, the operation information is information acquired by various sensors (not shown), and includes, for example, the vehicle position, speed, and station code, and more preferably, the occupancy rate, vehicle weight, number of passengers, etc. The storage battery information will be described later.

[0025] The data received by the data transmission / reception device 60 includes, for example, the vehicle operation plan and operation schedule, and the charging rate in each electrified section determined by the charging rate determination system 30 provided in the server 70. The operation plan and operation schedule may be stored in the vehicle control device 13 on the vehicle side, without being received from outside the vehicle.

[0026] The server 70 has a charging rate determination system 30, determines the charging rate for each electrified section based on data received from each vehicle, and transmits the charging rate information to each vehicle. It is desirable for the server 70 to receive data from as many vehicles as possible. For example, this data may be from multiple vehicles traveling on the same route, or multiple vehicles traveling on routes that share common transfer points with that route. This allows the server 70 to determine an appropriate charging rate that takes into account the operation information and battery information of many vehicles, and transmits the data to each vehicle.

[0027] The server 70 may also have a charging speed recording unit (not shown) that records the charging speed output by the charging speed determination system 30. By providing the charging speed recording unit to the server 70, the process of determining the charging speed and the process of transmitting the determined charging speed can be performed at different times, thereby increasing the flexibility of processing time and communication time. Furthermore, when transmitting to the vehicle, the charging speeds of the electrified section including the station can be transmitted together, thereby reducing the number of communications. Furthermore, if there is no disruption to the train schedule and there is no need to recalculate the charging speed based on operation information and battery information, the same charging speed as used during the previous operation may be used, for example. This reduces the computational load required to determine the charging speed.

[0028] FIG. 2 is a block diagram showing an example of the configuration of a storage battery system 20 according to an embodiment of the present invention. The storage battery system 20 is one storage battery system corresponding to one storage battery electric train traction system 1. Inside the storage battery system 20, storage battery boxes 21 are connected in series or parallel. Here, the storage battery boxes 21 are storage battery housing boxes covered with a box casing. In a railway vehicle, the storage battery system 20 is composed of multiple storage battery boxes 21, mainly due to limitations on installation size and weight. The storage battery system 20 also has a storage battery control device 201 shown in FIG. 1.

[0029] A plurality of battery modules (not shown) are connected in series or parallel inside the battery box 21. The battery box 21 also includes at least one battery box control board 211, which has functions such as monitoring the battery status, calculating the battery status, sending and receiving signals to and from higher-level control devices such as the battery control device 201, and controlling the battery box.

[0030] The battery control device 201 acquires battery information in each battery box 21 and controls the battery on a cell-by-cell, module-by-module, or box-by-box basis based on this battery information. Here, the battery information includes, for example, current, voltage, charge rate, and temperature for each cell, module, or box. Other information may include power, air temperature, capacity maintenance rate, and resistance increase rate. Furthermore, the acquired battery information may include vehicle speed, rotor frequency (of the motor provided in the battery system 20), and cooling conductance rate (e.g., the drive rate of a fan or cooling device for cooling the battery box 21) as information related to the amount of airflow hitting the battery box 21.

[0031] 3 is a block diagram showing an example of the configuration of the charging rate determination system 30 in the server 70. The railway vehicle 41 is a railway vehicle having a battery-powered electric train drive system. The charging rate determination system 30 includes an operation information and battery information storage unit 31 that stores operation information and battery information acquired from the railway vehicle 41, an upper / lower limit charging rate information storage unit 32 that stores upper / lower limit charging rate information, an electrified section stay time prediction unit 33 that predicts a stay time in an electrified section and a required charge amount prediction unit 34 that predicts a required charge amount in each electrified section based on the data from the operation information and battery information storage unit 31 and the data from the upper / lower limit charging rate information storage unit 32, and a charge rate determination unit 35 that determines a charge rate in each electrified section based on the data from the electrified section stay time prediction unit 33 and the required charge amount prediction unit 34.

[0032] The operation information and battery information accumulation unit 31 accumulates operation information and battery information received from a data transmission / reception device 60 (FIG. 1) provided in the railway vehicle 41 .

[0033] The upper and lower limit charging rate information storage unit 32 stores information on upper and lower limit charging rates that must be observed during operation. For example, upper and lower limit charging rates set by the railway operating company, a lower limit charging rate to prevent battery shortages, an upper limit charging rate to prevent deterioration of power efficiency, and upper and lower limit charging rates to suppress deterioration of the storage battery may be set and stored. Furthermore, the upper and lower limit charging rates may be classified into cases such as during a normal schedule, when the storage battery is deteriorated, and when the schedule is disrupted, and used to determine the charging speed based on the operation information and data from the storage battery information storage unit 31. Furthermore, the upper and lower limit charging rates may be updated in response to schedule changes, etc. Examples of setting values ​​for the upper and lower limit charging rates will be described later.

[0034] The electrified section stay time prediction unit 33 predicts the stay time or chargeable time in each electrified section from the operation information received by the server 70 and stored in the operation information and storage battery information storage unit 31. For example, the stay time in electrified section A is predicted using the following formula 1 based on the railway operation plan and operation information.

[0035] The required charge amount prediction unit 34 predicts the required charge amount in each electrified section based on the operation information, the battery information stored in the battery information storage unit 31, and the upper and lower limit charging rate information stored in the upper and lower limit charging rate information storage unit 32. An example of a prediction formula for the required charge amount will be described later.

[0036] The charging rate determination unit 35 predicts the charging rate in each electrified section based on the electrified section stay time predicted by the electrified section stay time prediction unit 33 and the required charging amount in each electrified section predicted by the required charging amount prediction unit 34. Here, the electrified section also includes stations equipped with charging facilities. For example, the charging rate in electrified section A is predicted using the following equation 2.

[0037] The charging rate output from the server 70 is reflected in the train operation plan and the storage battery charge / discharge control plan. The train operation plan and the storage battery charge / discharge control plan can be reflected, for example, by manually changing the plan on-site or by remotely changing the plan from an external server.

[0038] 4 is a flowchart showing the processing of the charging rate determination method. The processing steps will be described below. Each processing step is executed by the server 70, but the execution entity will not be described below.

[0039] Step 400 (S400): Processing begins.

[0040] Step 401 (S401): Obtain the train schedule, as well as operation information and battery information through communications from the railcars. If operation information cannot be obtained or is not required, the train schedule alone can be used as the operation information. However, it is desirable to obtain operation information in order to determine an appropriate charging rate in response to schedule disruptions, occupancy rates, etc.

[0041] Step 402 (S402): Obtain upper and lower limit charging rates set as predetermined values. As will be described in detail later, the upper and lower limit charging rates may be set as different values ​​for each electrified section, and may be updated as appropriate depending on battery information and the status of train schedule disruptions.

[0042] Step 403 (S403): By appropriately using the train schedule or operation information, battery information, and upper and lower limit charging rates obtained in step 401 (S401), the stay time and required charging amount in each electrified section are predicted.

[0043] Step 404 (S404): The charging speed in each electrified section is determined based on the stay time and required charging amount in each electrified section predicted in step 403 (S403).

[0044] Step 405 (S405): End the process.

[0045] FIG. 5 shows an example of a case where the charging rate is varied for each electrified section (each charging facility) and reflected in the train operation plan and the battery charge / discharge control plan. The electrified section refers to a section where charging is possible from overhead lines, but as mentioned above, includes stations equipped with charging facilities. Here, it is assumed that the upper limit charging rate is uniform regardless of the electrified section, and charging is performed up to the upper limit charging rate in each electrified section. For comparison, the case where no charging rate control is performed, i.e., charging is performed at a constant charging rate regardless of the electrified section, is also shown.

[0046] Without charging speed control, the charging speed in each electrified section is constant, and there may be extra charging time after charging up to the upper limit of charging rate. With charging speed control, the charging speed is reduced to a level that allows charging up to the upper limit of charging rate within the time spent in the electrified section, and this is reflected in the train operation plan and battery charge / discharge control plan. The battery temperature trend in the reflected train operation plan and battery charge / discharge control plan suppresses the charging current value in each electrified section and suppresses heat generation in the battery, thereby suppressing the rise in battery temperature and ultimately reducing battery deterioration.

[0047] Figure 6 shows another example of a case in which the charging rate is varied for each electrified section (each charging facility) and reflected in the train operation plan and the battery charge / discharge control plan. Here, we assume that the minimum charging rate is set to a uniform value regardless of the electrified section, and that the minimum charging amount that does not fall below the minimum charging rate is charged in each electrified section. In this case, the charging rate is reduced so that only the required charging amount is charged for each electrified section, and this is reflected in the train operation plan and the battery charge / discharge control plan.

[0048] The battery temperature trends in the reflected train operation plan and battery charge / discharge control plan are compared to charging up to the upper limit of charge rate shown in Figure 5. This further suppresses the charging current value in each electrified section and suppresses heat generation in the batteries, thereby suppressing the rise in battery temperature and further reducing the risk of reaching the upper limit temperature and battery deterioration. Also, although the charge rate in the reflected train operation plan and battery charge / discharge control plan is lower overall compared to charging up to the upper limit of charge rate shown in Figure 5, the train operation plan and battery charge / discharge control plan maintain the charge amount necessary to ensure a charge rate at or above that allows running, minimizing the risk of running out of power.

[0049] In the examples shown in Figures 5 and 6, the upper and lower limit charging rates are the same for each electrified section, but the upper and lower limit charging rates may be variable for each electrified section. In Figures 5 and 6, the change in the charging rate in the non-electrified section is shown to be linear for ease of understanding.

[0050] As described above, according to this embodiment, by appropriately slowing down the charging rate to the storage battery system, it is possible to suppress the temperature rise of the storage battery and the deterioration of the storage battery during charging.

[0051] Further benefits can be expected from the following modes A to G. A) The upper and lower limit charging rates are set within a range that allows for good regeneration acceptance efficiency without running out of power, and the required charging amount is determined based on these values. This further slows the charging rate, further suppressing increases in battery temperature and battery degradation, while minimizing the impact on operation such as running out of power and deterioration in power efficiency. In addition, the charging rate is updated appropriately, taking into account the deterioration state of the battery and the performance required for driving. This further suppresses increases in battery temperature and battery degradation, while minimizing the impact on operation such as running out of power and deterioration in power efficiency.

[0052] The upper and lower limits of the charging rate are set for each electrified section, in other words, for each station and section where charging is possible. This further reduces the charging speed, thereby suppressing battery temperature rise and battery deterioration.

[0053] Based on the operation information, the charge amount for each electrified section is adjusted to reduce the charge amount for electrified sections where the battery temperature is high, for example, electrified sections with short charging times. This makes it possible to further suppress the rise in battery temperature.

[0054] D) Information on operation, battery information, and upper and lower limit charging rates is managed on a server outside the vehicle, and operation, battery, and charging rate information for each vehicle is sent and received via wireless communication. When there is a change in the schedule, battery deterioration, or a disruption to the schedule, various information is acquired again, and the charging rate is updated on the server outside the vehicle and sent to the vehicle, and the charging rate is adjusted based on the updated information. This minimizes the impact on operation, such as running out of power or worsening electricity costs, while suppressing increases in battery temperature and battery deterioration, even when there is a change in the schedule, battery deterioration, or a disruption to the schedule. The formula for predicting the required charging amount when the battery deteriorates or the schedule is disrupted is described below.

[0055] By predicting the required charging capacity for each vehicle, the charging speed can be temporarily increased even when multiple vehicles simultaneously stop at a station with a small charging capacity, such as during a schedule disruption. This makes it possible to create a charging plan that reduces charging time and minimizes service delays. In this case, by setting an upper limit on the charging speed to prevent battery temperature increases and deterioration, charging time can be minimized within a range that does not cause battery temperature increases or battery deterioration during charging. In addition, if there is an opportunity to stop at another electrified section before stopping at a station with a small charging capacity, the charging speed in that other electrified section can be changed to charge excess capacity in advance, further reducing the charging time and charging speed at stations with a small charging capacity.

[0056] F) The charging speed for each electrified section is recorded by the charging speed recording unit 131 provided on the vehicle. This reduces the number of times data is received from the server and minimizes power consumption and other issues caused by communication, for example, by charging at the same charging speed as the previous time when there is no disruption to the train schedule.

[0057] A means will be installed in the driver's cab to notify the driver when the required amount of charge for the next station has been reached. This will make the charging status visible and reduce the driver's anxiety about operating vehicles with a lower charge rate than before.

[0058] Next, a method for predicting the required charge amount and the set values ​​for the upper and lower limit charging rates will be described. There are several prediction formulas and set values ​​for the required charge amount and the upper and lower limit charging rates, depending on the railway vehicle operation policy. Below, examples of the prediction formula for the required charge amount or the set values ​​for the upper and lower limit charging rates will be described for the normal schedule, and for the case where the storage battery is deteriorated or the schedule is disrupted.

[0059] First, the following two methods can be considered for predicting the required charging amount in the case of a normal timetable. In the first method, the upper limit charging rate is set to a uniform value regardless of the electrified section, and charging is performed up to the upper limit charging rate in each electrified section. In this case, the required charging amount is predicted using the following equation 3. Here, for the sake of the following explanation, this method will be referred to as charging method X1.

[0060] The charge rate at the time of arrival at the electrified section A may be predicted based on information such as the vehicle's electricity cost and mileage, based on operation plan information for a regular timetable. Alternatively, the charge rate may be predicted based on operation information and storage battery information accumulated in the operation information and storage battery information accumulation unit 31 (FIG. 3). Alternatively, the server 70 may receive values ​​at or near the time of arrival at the electrified section in real time, and the charge rate may be predicted based on that data.

[0061] This method X1 operates the storage battery at a high charging rate at all times, so it can reduce the risk of running out of power even when the running time between stations is longer than normal (when the timetable is changed) due to a disruption in the train schedule. In addition, if the upper limit on the charging rate is set within a range that does not worsen the power efficiency, it can also prevent the power efficiency from worsening.

[0062] The second method is to set the minimum charging rate to a uniform value regardless of the electrified section, and charge the vehicle to the minimum amount necessary for running in each electrified section. In this case, the required charging amount is predicted using the following equation 4. For the purposes of the following explanation, this method will be referred to as charging method X2.

[0063] The capacity consumed in the non-electrified section between electrified sections A and B (the non-electrified section between electrified section A and electrified section B) may be predicted based on the operation plan information of the normal timetable, from information such as the electric cost of the vehicle and the distance traveled in the non-electrified section between electrified sections A and B. Alternatively, the prediction may be based on the operation information stored in the operation information and storage battery information storage unit 31 (FIG. 3).

[0064] This method X2 minimizes the amount of charge, which in turn minimizes the rise in battery temperature and battery degradation during charging. It also predicts the amount of charge required for running and charges accordingly, reducing the risk of running out of battery power. Furthermore, by providing a margin for the minimum charging rate, it is possible to reduce the risk of running out of battery power when train travel times between stations are extended beyond the normal timetable (due to timetable changes) due to disruptions to the train schedule.

[0065] Next, we will explain the upper and lower limit charging rate settings for when the storage battery deteriorates. When the storage battery deteriorates, the voltage fluctuation becomes larger, so the upper and lower limit charging rates need to be updated to prevent power shortages and deterioration in power consumption. For example, when a new storage battery deteriorates, upper and lower limit charging rates can be set to prevent power shortages and deterioration in power consumption, and the setting values ​​can be periodically reviewed based on the vehicle's storage battery information.

[0066] In addition, charging speed data based on a safe charging plan may be recorded in the charging speed recording unit 131 shown in Figure 1, and when the storage battery control device 201 detects that the upper or lower limit charging rates have been exceeded, it may automatically switch to the safe charging plan and notify the server 70 to reset the upper or lower limit charging rates.

[0067] Finally, we will explain the formula for predicting the required charging amount when a train schedule is disrupted, and the set values ​​for the upper and lower limit charging rates. There are three main impacts that can be considered on charging time and charging rate when a train schedule change occurs due to a train schedule disruption: (1) The time spent in non-electrified sections (= the time interval between an electrified section and the next electrified section) becomes longer than normal, increasing the risk of running out of power. (2) Arrival times at electrified sections are delayed, shortening charging time. Alternatively, there is a demand to keep charging time (= time spent in an electrified section) as short as possible. (3) When multiple trains are staying in an electrified section with a small charging facility capacity, their charging times overlap, creating periods when charging is not possible.

[0068] Next, we will explain how to predict the required charging amount, set the upper and lower limit charging rates, and determine the charging speed according to each of the above situations. (1) When the stay time in a non-electrified section is longer than that of a normal schedule, for example, the following three methods can be considered as a prediction formula for the required charging amount and set the upper and lower limit charging rates.

[0069] (1-1) In the normal timetable, the upper limit of the charging rate is set to a high value that will prevent power shortages regardless of the electrified section, and the charging method X1 described above is adopted. This method (1-1) operates at a high charging rate at all times, minimizing the risk of power shortages during timetable disruptions.

[0070] (1-2) In the normal timetable, the minimum charging rate is set to a uniform value regardless of the electrified section, and the charging method X2 described above is used. The minimum charging rate is set in advance to a value that includes a margin that takes into account timetable changes due to timetable disruptions. This method (1-2) can suppress battery temperature increases and battery degradation in the normal timetable, while also reducing the risk of running out of power when timetable changes are made due to timetable disruptions.

[0071] Figure 7 shows three examples of cases in which the minimum charging rate or charging rate is changed and reflected in the train operation plan and battery charge / discharge control plan when a schedule change occurs due to a schedule disruption. (1-3) (1-3) shown in the upper part of Figure 7 shows an example in which at least the minimum charging rate or charging rate is changed and reflected in the train operation plan and battery charge / discharge control plan when a schedule disruption occurs. The above charging method X2 is used in the normal schedule. When a schedule disruption occurs, the changed schedule is sent to the server, the minimum charging rate is changed to a higher value, and the required charging rate and charging rate are updated. This prevents battery shortages even when a schedule disruption causes a longer stay in a non-electrified section and increases the required charging amount. If the first electrified section visited after a schedule change due to a schedule disruption is electrified section B, the required charging amount for electrified section B is predicted using the following equation 5.

[0072] This method (1-3) can minimize battery temperature rise and battery deterioration during normal train schedules, while reducing the risk of running out of power when schedule changes occur due to train schedule disruptions.

[0073] (2) When the arrival time at the electrified section is delayed and the charging time is shortened or when the charging time needs to be shortened as much as possible, the formula for predicting the required charging amount and the setting values ​​for the upper and lower limit charging rates can be considered to be a combination of the above methods (1-1) to (1-3) and the following method. Below, we will explain the case where the above method (1-3) is combined.

[0074] (2-1) (2-1) in the middle of Figure 7 is a graph showing an example of changing the charging rate for electrified section B and reflecting this in the railway operation plan and the battery charge / discharge control plan when a schedule change due to a schedule disruption shortens the stay time in electrified section B. When a schedule disruption occurs, the charging rate is updated based on the changed stay time in the electrified section and the required charge amount for one of methods (1-1) to (1-3). Method (2-1) can shorten the charging time after a schedule disruption. However, because the increased charging rate increases the risk of battery temperature rise and battery degradation, an upper limit for the charging rate during a schedule disruption, such as method (2-2), may be set or updated in advance. Conversely, if a schedule disruption shortens the stay time in the electrified section, such as when the gap with the preceding train narrows, the charging rate may be reduced depending on the stay time and required charge amount. This can prevent battery temperature rise and battery degradation.

[0075] (2-2) (2-2) shown in the lower part of Figure 7 is a graph showing an example of the case where a charging speed upper limit is set in the method described above in (2-1) and reflected in the train operation plan and the battery charge / discharge control plan. If the charging speed in electrified section B updated after the timetable change is equal to or greater than the charging speed upper limit, charging is performed at the charging speed upper limit in electrified section B, and the required charging amount in the next electrified section C is recalculated based on the charging amount in electrified section B, and the charging speed is updated.

[0076] (2-3) If you want to shorten the charging time as much as possible, when a disruption occurs, predict the required charging amount using one of the methods (1-1) to (1-3) above and charge at the upper limit charging rate. The upper limit charging rate is set in consideration of the rise in battery temperature and battery degradation. This method (2-3) can minimize the charging time while suppressing the rise in battery temperature and battery degradation.

[0077] (3) The following methods can be considered as a method for predicting the required charging amount and a method for determining the upper and lower limit charging rates and charging speed when multiple vehicles are staying in an electrified section with a small charging facility capacity (hereinafter referred to as electrified section F) and their charging times overlap, resulting in a time period when charging is not possible. Figure 8 shows two examples of when the charging speed is made variable and reflected in the railway operation plan and the battery charge / discharge control plan when a schedule disruption occurs and more vehicles than usual are staying in an electrified section with a small charging facility capacity.

[0078] (3-1) (3-1) shown in the upper part of Figure 8 is an example that assumes a situation in which a schedule disruption occurs in another train set, there is no opportunity for the train set to stay in another electrified section, the train arrives at the same time as another train set in electrified section F with a small charging facility capacity, and the charging of the other train set is given priority. By applying the above-mentioned (2-1) or (2-2), the charging time in electrified section F with a small charging facility capacity can be reduced, and operation delays can be minimized. In this case, the charging order of each vehicle can be adjusted depending on the priority of vehicle departure. Furthermore, if it is desired to shorten the charging time in electrified section F with a small charging facility capacity as much as possible, by applying the above-mentioned (2-3), the charging time in electrified section F can be reduced and operation delays can be minimized.

[0079] (3-2) (3-2) shown in the lower part of Figure 8 is an example assuming that after a schedule disruption, there is an opportunity to stop at another electrified section B before stopping at electrified section F with a small charging facility capacity. The required charging amount for electrified section B is calculated using the above-mentioned formula 3 and charged up to the upper limit charging rate, and the required charging amount for electrified section F with a small charging facility capacity is calculated using the following formula 6 and charged at the upper limit charging rate. Here, as shown in the lower part of Figure 8, the next electrified section after electrified section F is electrified section D.

[0080] This method (3-2) can reduce the charging speed or charging time in electrified section F, which has a small charging facility capacity, compared to the previous method (2-1), and can further reduce the risk of service delays and battery temperature increases. Note that if there is an opportunity to stop in multiple other electrified sections before stopping in electrified section F, the charging rate may be increased in stages up to the upper limit.

[0081] The above-described method for predicting the required charge amount, the setting values ​​of the upper and lower limit charging rates, and the method for determining the charging rate may be applied in combination with other methods in part or in whole.

[0082] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the gist of the present invention.

[0083] 1... Battery electric train drive system, 2... Pantograph, 5... Converter, 6... Motor inverter, 7... Motor, 8... Reducer, 9... Wheelset, 10... Auxiliary equipment inverter, 11... Auxiliary equipment, 12... Driver's cab, 13... Vehicle control device, 131... Charging speed recording unit, 14... Overhead line, 20... Battery system, 201... Battery control device, 21... Battery box, 211... Battery box control board, 30... Charging speed determination system, 31... Operation information and battery information storage unit, 32... Upper and lower limit charging amount information storage unit, 33... Electrified section residence time prediction unit, 34... Required charging amount prediction unit, 35... Charging speed determination unit, 41... Railway vehicle, 60... Data transmission / reception device, 70... Server

Claims

A railway system including an on-board device mounted on a railway vehicle and a server that transmits and receives data to and from the on-board device, the on-board device transmits storage battery information indicating a state of the storage battery mounted on the railway vehicle to the server; The server predicting the stay time of the railway vehicle in an electrified section on which the railway vehicle runs and the required charge amount of the storage battery based on operation information indicating the operating state of the railway vehicle or a train schedule of the railway vehicle, the upper and lower limit charge rates of the storage battery, and the storage battery information received from the on-board device; determining a charging rate of the storage battery in the electrified section based on the predicted stay time and the required charging amount; The determined charging speed is transmitted to the on-board device. A railway system characterized by:

2. The railway system according to claim 1, The on-board device also transmits the operation information to the server, The server further uses the received operation information to predict the stay time and the required charge amount. A railway system characterized by:

3. The railway system according to claim 1 or 2, The upper and lower limit charging rates are set for each electrified section. A railway system characterized by:

4. The railway system according to claim 1, In a normal timetable, the server sets the upper limit charging rate to a uniform value regardless of the electrified section or the lower limit charging rate to a uniform value regardless of the electrified section, and when a timetable change occurs, makes either the lower limit charging rate or the charging speed variable. A railway system characterized by:

5. The railway system according to claim 4, When setting the upper limit charging rate to a uniform value regardless of the electrified section, the server predicts a required charging amount of the storage battery in the electrified section based on the capacity of the storage battery and a difference between the upper limit charging rate and the charging rate at the time of arrival in the electrified section. A railway system characterized by:

5. The railway system according to claim 4, When setting the lower limit charging rate to a uniform value regardless of the electrified section, the server predicts the required charging amount of the storage battery in the electrified section based on the capacity consumed in a non-electrified section between the electrified section and the next electrified section. A railway system characterized by:

7. A railway system according to claim 1, The on-board device includes a charging speed recording unit that records the charging speed for each electrified section. A railway system characterized by:

8. A railway system according to any one of claims 1 to 7, The on-board device includes a driver's cab equipped with a display that displays at least a target charging rate of the storage battery for each electrified section and a predicted value of the charging rate when the storage battery is charged. A railway system characterized by: 　 An on-board device that is mounted on a railway vehicle and that configures a railway system together with a server, transmitting operation information indicating the operating status of the railway vehicle and storage battery information indicating the status of a storage battery mounted on the railway vehicle to the server that transmits and receives data to and from the on-board device; receiving from the server a charging rate for the storage battery in the electrified section that is determined by the server based on the stay time of the railway vehicle in the electrified section on which the railway vehicle runs and the required charge amount of the storage battery; Controlling the storage battery based on the received charging rate An on-board device characterized by: 　 A server that configures a railway system together with an on-board device mounted on a railway vehicle, receiving, from the on-board device, operation information indicating the operating status of the railway vehicle and storage battery information indicating the status of the storage battery mounted on the railway vehicle; predicting the stay time of the railway vehicle in the electrified section along which the railway vehicle runs and the required charge amount of the storage battery based on the operation information, the storage battery information, and the upper and lower limit charge rates of the storage battery; determining a charge rate for the storage battery in the electrified section from the stay time and the required charge amount; and transmitting the determined charge rate to the on-board device; A server characterized by: 　 A charging control method for a storage battery mounted on a railway vehicle, comprising: predicting a stay time of the railway vehicle in an electrified section on which the railway vehicle runs and a required charge amount of the storage battery based on operation information indicating the operation state of the railway vehicle or a train schedule of the railway vehicle, upper and lower limit charge rates of the storage battery, and storage battery information indicating the state of the storage battery; A charging rate of the storage battery in the electrified section is determined based on the predicted stay time and the required charging amount. A method for controlling charging of a storage battery. 　 The method for controlling charging of a storage battery according to claim 11, The upper and lower limit charging rates are set for each electrified section. A method for controlling charging of a storage battery. 　 The method for controlling charging of a storage battery according to claim 11 or 12, In a normal timetable, the upper limit charging rate of the upper and lower limit charging rates is set to a uniform value regardless of the electrified section, or the lower limit charging rate is set to a uniform value regardless of the electrified section, and when a timetable change occurs, either the lower limit charging rate or the charging speed is made variable. A method for controlling charging of a storage battery. 　 The method for controlling charging of a storage battery according to claim 13, When the upper limit charging rate is set to a uniform value regardless of the electrified section, the required charging amount of the storage battery in the electrified section is predicted based on the capacity of the storage battery and the difference between the upper limit charging rate and the charging rate at the time of arrival at the electrified section. A method for controlling charging of a storage battery. 　 The method for controlling charging of a storage battery according to claim 13, When the lower limit charging rate is set to a uniform value regardless of the electrified section, the required charging amount of the storage battery in the electrified section is predicted based on the capacity consumed in a non-electrified section between the electrified section and the next electrified section. A method for controlling charging of a storage battery.

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