Actual Delay Detection Device, Worsening Differentiation Device, Brake Control Device, Actual Delay Detection Method, Worsening Differentiation Method and Brake Control Method

Abstract

An actual deceleration detection device (51) comprises a speed detection device (53) and a determination unit (54). The speed detection device (53) detects the speed of a rail vehicle during a target period in which the rail vehicle is decelerated not by an electric braking force, but exclusively by a mechanical braking force. The rail vehicle is configured to be decelerated by at least one of the electric braking forces and the mechanical braking force. The determination unit (54) determines an actual deceleration of the rail vehicle during the target period based on a change in the speed detected by the speed detection device (53).

Description

Actual deceleration acquisition device, deterioration determination device, brake control device, actual deceleration acquisition method, deterioration determination method, and brake control method

[0001] The present disclosure relates to an actual deceleration acquisition device, a deterioration determination device, a brake control device, an actual deceleration acquisition method, a deterioration determination method, and a brake control method.

[0002] Railway vehicles accelerate by receiving driving force from an electric motor that rotates when supplied with power from a power source. Some railway vehicles decelerate by receiving mechanical braking force from a mechanical brake device and electric braking force generated by consuming power output from an electric motor operating as a generator. A monitoring device that monitors the actual deceleration of the railway vehicle is sometimes used to bring the actual deceleration of the railway vehicle closer to a target deceleration indicated by a brake command and stop the railway vehicle at a desired position. An example of this type of monitoring device is disclosed in Patent Document 1.

[0003] The monitoring device disclosed in Patent Document 1 calculates the deceleration of a railway vehicle from ATC (Automatic Train Control) data, and determines whether or not there is an abnormality in the vehicle based on the calculated deceleration.

[0004] Japanese Patent Application Laid-Open No. 2006-117190

[0005] The mechanical braking force of a mechanical brake device fluctuates more than the electric braking force. For example, the mechanical braking force may fluctuate due to aging degradation of components of the mechanical braking device. This may cause the actual deceleration of the railway vehicle to deviate from the target deceleration. In order to suppress the deviation between the actual deceleration and the target deceleration, it is preferable to determine the degree of deterioration of the mechanical braking device and control the mechanical braking device in accordance with the determination result. In order to determine the degree of deterioration of the mechanical braking device, the actual deceleration of the railway vehicle due to the mechanical braking force is required. However, when a railway vehicle is decelerated by the mechanical braking force and the electric braking force, the actual deceleration calculated by the monitoring device disclosed in Patent Document 1 is the actual deceleration based on the mechanical braking force and the electric braking force, making it difficult to obtain the actual deceleration of the railway vehicle due to the mechanical braking force.

[0006] The present disclosure has been made in consideration of the above-mentioned circumstances, and aims to provide an actual deceleration acquisition device that acquires the actual deceleration of a railway vehicle due to mechanical braking force, a deterioration determination device, a brake control device, an actual deceleration acquisition method, a deterioration determination method, and a brake control method.

[0007] To achieve the above object, the presently disclosed actual deceleration acquisition device includes a speed acquisition unit and a determination unit. The speed acquisition unit acquires the speed of the railway vehicle over a target period in a state in which the railway vehicle accelerates by receiving driving force from an electric motor that rotates when supplied with electric power and decelerates by receiving at least one of a mechanical braking force from a mechanical brake device and an electric braking force generated by consuming electric power generated by the electric motor operating as a generator, but is decelerating by receiving only the mechanical braking force, without receiving the electric braking force, of the mechanical braking force and the electric braking force. The determination unit determines the actual deceleration of the railway vehicle over the target period from the change in speed acquired by the speed acquisition unit.

[0008] The actual deceleration acquisition device according to the present disclosure acquires the speed of the railway vehicle over a target period while the railway vehicle is decelerating by applying only the mechanical brake force, but not by applying the electric brake force, and determines the actual deceleration of the railway vehicle from the acquired speed. Thus, the actual deceleration of the railway vehicle due to the mechanical brake force can be acquired.

[0009] FIG. 1 is a block diagram of a power conversion device according to embodiment 1; FIG. 2 is a block diagram of a brake control device according to embodiment 1; FIG. 3 is a block diagram of a deterioration determination device according to embodiment 1; FIG. 4 is a diagram showing a hardware configuration of a brake control device according to embodiment 1; FIG. 5 is a flowchart showing an example of actual deceleration acquisition processing performed by an actual deceleration acquisition device according to embodiment 1; FIG. 6 is a diagram showing an example of change in speed of a railway vehicle in embodiment 1; FIG. 7 is a flowchart showing an example of deterioration determination processing performed by the deterioration determination device according to embodiment 1; FIG. 8 is a flowchart showing an example of brake control processing performed by the brake control device according to embodiment 1;

[0010] Hereinafter, an actual deceleration acquisition device, a deterioration determination device, a brake control device, an actual deceleration acquisition method, a deterioration determination method, and a brake control method according to embodiments of the present disclosure will be described in detail with reference to the drawings. In the drawings, the same or equivalent parts are designated by the same reference numerals.

[0011] (Embodiment 1) Some railway vehicles, which have one or more cars, accelerate by receiving driving force from an electric motor and decelerate by receiving at least one of a mechanical braking force from a mechanical brake device and an electric braking force generated by consuming electricity generated by an electric motor operating as a generator.

[0012] An electric car of a railway vehicle is provided with a power conversion device 1 shown in FIG. 1 and an electric motor IM1 that receives power from the power conversion device 1. To avoid complicating the diagram, one electric motor IM1 is shown in FIG. 1 , but the power conversion device 1 actually supplies power to multiple electric motors IM1, for example, four electric motors IM1 provided in the same car. The electric motor IM1 is, for example, a three-phase induction motor that generates propulsive force for the railway vehicle. When the railway vehicle brakes, the electric motor IM1 operates as a generator and supplies AC power to the power conversion device 1.

[0013] The power conversion device 1 is mounted on a DC-fed railway vehicle, converts supplied DC power into AC power suitable for the electric motor IM1, and supplies the converted AC power to the electric motor IM1. The power conversion device 1 operates in response to an operation command S1 obtained from a master controller 91 provided in the driver's cab, for example.

[0014] The operation command S1 indicates a command corresponding to an operation by the operator to the master controller 91. Specifically, the operation command S1 indicates any one of a powering command to instruct the railway vehicle to accelerate, a braking command to instruct the railway vehicle to decelerate, and a coasting command to instruct the railway vehicle to travel by inertia. A coasting command means a state in which neither a powering command nor a braking command has been input.

[0015] When the operation command S1 includes a powering command, the power conversion device 1 supplies electric power to the electric motor IM1 in response to the powering command, thereby generating propulsive force for the railway vehicle, enabling the railway vehicle to travel.

[0016] A brake control device 21 is provided in each railcar. The brake control device 21 provided in the electric car controls the power conversion device 1 in accordance with a brake command included in the operation command S1. As a result, the power conversion device 1 converts AC power supplied from the electric motor IM1 into DC power and outputs the DC power. The DC power output by the power conversion device 1 is supplied to and consumed by other railcars in powered operation located near the railcar on which the power conversion device 1 is installed, thereby generating an electric brake force for the railcar.

[0017] The brake control device 21 generates a mechanical brake force by controlling the mechanical brake device 93 in accordance with the brake command included in the operation command S1 and the weight of the vehicle detected by the load compensation detector 92. The railway vehicle is decelerated by receiving at least one of the electric brake force and the mechanical brake force.

[0018] The brake control device 21 acquires the actual deceleration of the railway vehicle due to the mechanical braking force, determines the degree of deterioration of the mechanical braking device 93 according to the actual deceleration, and performs brake control according to the degree of deterioration of the mechanical braking device 93. Deterioration of the mechanical braking device 93 is not limited to deterioration of the components of the mechanical braking device 93, such as deterioration of friction materials and reduced mechanical efficiency of brake cylinders, but also includes deterioration of parts surrounding the mechanical braking device 93, such as deterioration of an electro-pneumatic converting valve that supplies air to the mechanical braking device 93. In the first embodiment, the brake control device 21 determines the degree of deterioration of the mechanical braking device 93 by determining whether or not the mechanical braking device 93 has deteriorated.

[0019] 1 shows one mechanical brake device 93 to avoid complicating the drawing, but a mechanical brake device 93 is provided for each wheel. For example, one vehicle may be provided with eight mechanical brake devices 93 corresponding to different wheels. The mechanical brake device 93 includes, for example, a brake shoe having a friction material that generates a mechanical braking force by contacting the wheel, and a brake cylinder attached to the brake shoe and supplied with air that is supplied from an air reservoir (not shown) and compressed by the brake control device 21.

[0020] 1 shows one speed sensor 94 to avoid complicating the drawing, but a speed sensor 94 is provided for each axle. For example, one vehicle may be provided with four speed sensors 94 corresponding to different axles.

[0021] The power conversion device 1 includes a terminal 1a connected to a power supply, a terminal 1b connected to ground, and a power conversion circuit 11 that converts DC power supplied from the power supply into power to be supplied to the electric motor IM1 and supplies the converted power to the electric motor IM1. The power conversion device 1 further includes a filter capacitor FC1 connected between primary terminals of the power conversion circuit 11, and a power conversion circuit control unit 12 that controls the power conversion circuit 11.

[0022] Terminal 1a is electrically connected to a power source, specifically, a current collector that acquires power supplied from a substation via a power supply line, via a reactor, contactor, etc. (not shown). For example, the current collector may be a pantograph that acquires power via an overhead line, which is an example of a power supply line, or a collector shoe that acquires power via a third rail, which is an example of a power supply line. Terminal 1b is grounded via a ground ring, ground brush, wheel, etc. (not shown).

[0023] The power conversion circuit 11 is formed, for example, by an inverter that can vary the effective voltage and frequency of the AC power it outputs. The power conversion circuit 11 has a plurality of switching elements, and the switching operation of each switching element is controlled by a power conversion circuit control unit 12. Each switching element is formed, for example, by an IGBT (Insulated Gate Bipolar Transistor) or a switching element using a wide bandgap semiconductor formed of SiC (Silicon Carbide), GaN (Gallium Nitride), diamond, or the like.

[0024] By controlling the multiple switching elements by the power conversion circuit control unit 12, the power conversion circuit 11 converts DC power supplied from the power source via the filter capacitor FC1 into three-phase AC power and supplies the three-phase AC power to the electric motor IM1, or converts the three-phase AC power supplied from the electric motor IM1 into DC power and charges the filter capacitor FC1 with the DC power.

[0025] One end of the filter capacitor FC1 is connected to the connection point between the terminal 1a and one of the primary terminals of the power conversion circuit 11. The other end of the filter capacitor FC1 is connected to the connection point between the terminal 1b and the other primary terminal of the power conversion circuit 11. The filter capacitor FC1 forms an LC filter together with a reactor (not shown) connected to the terminal 1a, and reduces harmonic components generated by the switching operations of the multiple switching elements of the power conversion circuit 11.

[0026] The power conversion circuit control unit 12 acquires an operation command S1 from the main controller 91. In response to the operation command S1, the power conversion circuit control unit 12 generates and outputs a power conversion control signal S2 that controls each switching element of the power conversion circuit 11. The power conversion control signal S2 is, for example, a PWM (Pulse Width Modulation) signal.

[0027] When the operation command S1 includes a powering command, the power conversion circuit control unit 12 determines a target torque, which is a target value of the torque of the electric motor IM1, based on the target acceleration, which is the target value of the acceleration of the railway vehicle indicated by the powering command, and the weight of the vehicle detected by the load-varying detector 92, and outputs a power conversion control signal S2 according to the target torque to the power conversion circuit 11.

[0028] When the driving command S1 includes a brake command, the power conversion circuit control unit 12 acquires a regeneration pattern S3 from the brake control device 21 and outputs a power conversion control signal S2 corresponding to a target electric brake force, which is a target value of the electric brake force indicated by the regeneration pattern S3, to the power conversion circuit 11. The power conversion circuit control unit 12 sends a regeneration feedback S4 indicating the actual electric brake force to the brake control device 21.

[0029] When the power conversion circuit control unit 12 receives a stop signal S5 from the brake control device 21 instructing the power conversion circuit 11 to stop, it outputs a power conversion control signal S2 to the power conversion circuit 11 to turn off multiple switching elements of the power conversion circuit 11.

[0030] As shown in Figure 2, the brake control device 21 has a brake control unit 31 that controls the power conversion circuit control unit 12 and the mechanical brake device 93, and a deterioration determination device 41 that determines the degree of deterioration of the mechanical brake device 93.

[0031] The brake control unit 31 includes a target brake force determination unit 32 that determines a target brake force, which is a target value of the brake force for achieving the target deceleration, in accordance with the target deceleration indicated by the brake command included in the driving command S1, and a regeneration control unit 33 that controls the power conversion circuit control unit 12. The brake control unit 31 further includes a brake force adjustment unit 34 that adjusts the target brake force, and a mechanical brake control unit 35 that controls the mechanical brake device 93.

[0032] The target braking force determination unit 32 calculates the target braking force by multiplying the target deceleration indicated by the brake command by the vehicle weight detected by the load response detector 92. The target braking force determination unit 32 sends the calculated target braking force to the regeneration control unit 33, the braking force adjustment unit 34, and the mechanical brake control unit 35.

[0033] The regeneration control unit 33 determines a target electric brake force from the target brake force, and sends a regeneration pattern S3 indicating the target electric brake force to the power conversion circuit control unit 12.

[0034] The braking force adjustment unit 34 adjusts the target braking force in accordance with the determination result of the deterioration determination device 41. In particular, when the deterioration determination device 41 determines that the mechanical brake device 93 has deteriorated, the braking force adjustment unit 34 adjusts the target braking force and sends the adjusted target braking force to the mechanical brake control unit 35. When the deterioration determination device 41 determines that the mechanical brake device 93 has not deteriorated, the braking force adjustment unit 34 sends the target braking force acquired from the target braking force determination unit 32 to the mechanical brake control unit 35.

[0035] The mechanical brake control unit 35 acquires regenerative feedback S4 indicating the actual electric brake force from the power conversion circuit control unit 12. The mechanical brake control unit 35 determines the mechanical brake force based on the target electric brake force acquired from the target brake force determination unit 32, the target brake force adjusted by the brake force adjustment unit 34, and the actual electric brake force. If the actual electric brake force is less than the target electric brake force acquired from the target brake force determination unit 32, the mechanical brake control unit 35 uses the difference between the target electric brake force acquired from the brake force adjustment unit 34 and the actual electric brake force as the target mechanical brake force.

[0036] When the deterioration determination device 41 determines that the mechanical brake device 93 has deteriorated, the target brake force acquired from the brake force adjustment unit 34 is the target brake force adjusted by the brake force adjustment unit 34 in accordance with the determination result of the deterioration determination device 41. On the other hand, when the deterioration determination device 41 determines that the mechanical brake device 93 has not deteriorated, the target brake force acquired from the brake force adjustment unit 34 matches the target brake force output by the target brake force determination unit 32. As a result, the target mechanical brake force is adjusted in accordance with the determination result of the deterioration determination device 41.

[0037] The mechanical brake control unit 35 controls the mechanical brake device 93 according to the target mechanical brake force. More specifically, the mechanical brake control unit 35 determines, from the target mechanical brake force, a target pressure that is a target value for the pressure of air inside the brake cylinder of the mechanical brake device 93. The mechanical brake control unit 35 controls the mechanical brake device 93 by adjusting the pressure of fluid supplied from an air reservoir according to the target pressure and sending the fluid to the mechanical brake device 93.

[0038] The mechanical brake control unit 35 does not control the mechanical brake device 93 if the actual electric brake force is equal to or greater than the target electric brake force acquired from the target brake force determination unit 32. In this case, no mechanical brake force is generated.

[0039] As shown in Figure 3, the deterioration determination device 41 has an actual deceleration acquisition device 51 that acquires the actual deceleration of the railway vehicle, and a determination unit 42 that determines the degree of deterioration of the mechanical brake device 93 based on the actual deceleration acquired from the actual deceleration acquisition device 51.

[0040] The actual deceleration acquisition device 51 has a switching unit 52 that outputs a stop signal S5 to the power conversion circuit control unit 12 to instruct the power conversion circuit 11 to stop, a speed acquisition unit 53 that determines the speed of the railway vehicle from the measurement value of the speed sensor 94, and a determination unit 54 that determines the actual deceleration of the railway vehicle from changes in the speed of the railway vehicle during the target period.

[0041] When a start condition for starting the process of obtaining the actual deceleration is satisfied, the switching unit 52 outputs a stop signal S5 to the power conversion circuit control unit 12 to stop the power conversion circuit 11, specifically, to stop the power conversion of the power conversion circuit 11. The start condition is determined, for example, according to the running position of the railway vehicle. As an example, the start condition is that the railway vehicle reaches a braking start position just before a specified stop station for the first time in its daily operation. The stop station is preferably located in an area with a sufficiently small gradient. When the operation command S1 includes a brake command and the power conversion circuit 11 stops, the railway vehicle decelerates by receiving only the mechanical brake force out of the mechanical brake force and the electric brake force. While the power conversion circuit 11 is stopped, the railway vehicle does not receive the electric brake force.

[0042] When the switching unit 52 outputs the stop signal S5, the speed acquisition unit 53 acquires the speed of the railway vehicle from the measurement value of the speed sensor 94 provided for each axle. For example, when the speed acquisition unit 53 receives a notification from the switching unit 52 that the stop signal S5 has been output, the speed acquisition unit 53 determines the speed of the railway vehicle from the measurement value of the speed sensor 94 and stores it in a storage device (not shown). For example, the speed acquisition unit 53 determines the axle speed of each axle of the vehicle from the measurement value of the speed sensor 94, sets the maximum value of the axle speeds of each axle as a reference axle speed, and determines the speed of the vehicle from the reference axle speed.

[0043] The speed acquisition unit 53 repeatedly determines the speed of the railway vehicle from the measurement values ​​of the speed sensor 94 over a target period, for example, a period from when the start condition is met until the railway vehicle stops, and stores the determined speed in a storage device. The speed acquisition unit 53 sends the railway vehicle speed over the target period to the determination unit 54.

[0044] The determination unit 54 determines the actual deceleration of the railway vehicle from the change in the speed of the railway vehicle during the target period. The determination unit 54 obtains the actual deceleration of the railway vehicle from the change in the speed of the railway vehicle during the target period and the duration of the target period, based on the speed obtained by the speed acquisition unit 53. In the first embodiment, the determination unit 54 uses the speed of the railway vehicle obtained by the speed acquisition unit 53 during the target period, specifically, the speed of the railway vehicle at the start of the target period and the speed of the railway vehicle at the end of the target period, i.e., 0 km / h.

[0045] The determination unit 54 determines the actual deceleration β using, for example, the following equation (1). In the following equation (1), V1 indicates the initial braking speed (unit: km / h) at the start of the target period, that is, the speed when the train reaches the braking start position and braking is started. In the following equation (1), s indicates the braking distance, specifically, the distance (unit: m) from the braking start position just before the stop station to the stop station. In the following equation (1), s indicates the braking distance, specifically, the distance (unit: m) from the braking start position just before the stop station to the stop station. ０ is expressed by the following formula (2). ０ is the free running time. The determination unit 54 is assumed to have stored therein information on the braking distance and the free running time in advance. The determination unit 54 sends the determined actual deceleration to the determination unit 42.

[0046]

[0047]

[0048] The determination unit 42 determines the degree of deterioration of the mechanical brake device 93 by comparing the actual deceleration acquired from the actual deceleration acquisition device 51 with the target deceleration indicated by the brake command. In detail, the determination unit 42 determines the degree of deterioration of the mechanical brake device 93 based on whether the ratio of the difference between the actual deceleration and the target deceleration to the target deceleration is within a target range.

[0049] For example, the determination unit 42 calculates the ratio by subtracting the absolute value of the target deceleration from the absolute value of the actual deceleration and dividing the result by the absolute value of the target deceleration. When the absolute value of the actual deceleration is smaller than the absolute value of the target deceleration, in other words, when the target deceleration is not achieved and the railway vehicle is not sufficiently decelerated, the ratio calculated as described above will be a negative value. When the absolute value of the actual deceleration is larger than the absolute value of the target deceleration, in other words, when the railway vehicle is decelerating more rapidly than the target deceleration, the ratio calculated as described above will be a positive value.

[0050] As an example, if the absolute value of the ratio of the difference between the actual deceleration and the target deceleration to the target deceleration is within a target range that is an allowable range for the braking performance of the mechanical brake device 93, for example, a range of 0 or more and 0.15 or less, it can be assumed that there is no deterioration in the mechanical brake device 93. If the absolute value of the ratio of the difference between the actual deceleration and the target deceleration to the target deceleration is greater than 0.15, it can be assumed that there is deterioration in the mechanical brake device 93.

[0051] The determination unit 42 sends the determination result and the ratio of the difference between the actual deceleration and the target deceleration to the target deceleration to the brake control unit 31. The determination unit 42 sends, as the determination result, a determination result signal that is at L (Low) level if the ratio of the difference between the actual deceleration and the target deceleration to the target deceleration is within the target range, and that is at H (High) level if the ratio of the difference between the actual deceleration and the target deceleration to the target deceleration is not within the target range.

[0052] The hardware configuration of the brake control device 21 having the above-described configuration is shown in Figure 4. The brake control device 21 includes a processor 81, a memory 82, and an interface 83. The processor 81, the memory 82, and the interface 83 are connected to one another via a bus 80. The functions of each unit of the brake control device 21 are realized by software, firmware, or a combination of software and firmware. The software and firmware are written as programs and stored in the memory 82. The processor 81 reads and executes the programs stored in the memory 82, thereby realizing the functions of each unit described above. In other words, the memory 82 stores programs for executing the processing of each unit of the brake control device 21.

[0053] The memory 82 includes, for example, non-volatile or volatile semiconductor memory such as RAM (Random Access Memory), ROM (Read-Only Memory), flash memory, EPROM (Erasable Programmable Read Only Memory), EEPROM (Electrically Erasable and Programmable Read-Only Memory), magnetic disk, flexible disk, optical disk, compact disk, mini disk, DVD (Digital Versatile Disc), etc.

[0054] The brake control device 21 is connected to a main controller 91, a power conversion circuit control unit 12, a load compensation detector 92, a mechanical brake device 93, and a speed sensor 94 via an interface 83. The interface 83 has interface modules that comply with one or more standards depending on the connected devices.

[0055] The actual deceleration acquisition process performed by the actual deceleration acquisition device 51 included in the brake control device 21 having the above configuration will be described below with reference to Fig. 5. When the railway vehicle starts operation, the actual deceleration acquisition device 51 starts the process shown in Fig. 5.

[0056] The switching unit 52 determines whether a start condition for starting the actual deceleration acquisition process is satisfied (step S11). If the start condition is not satisfied (step S11; No), the process of step S11 is repeated. If the start condition is satisfied (step S11; Yes), the switching unit 52 sends a stop signal S5 to the power conversion circuit control unit 12 to stop the power conversion circuit 11 (step S12). Specifically, upon receiving the stop signal S5 from the switching unit 52, the power conversion circuit control unit 12 sends a power conversion control signal S2 to the power conversion circuit 11 to turn off multiple switching elements of the power conversion circuit 11. As a result, the power conversion circuit 11 is stopped.

[0057] For example, as shown in Figure 6, assume that a railway vehicle traveling at speed V1 reaches a braking start position just before a designated stop station for the first time in a day's operation at time T1, and the start condition is met. When the railway vehicle reaches the braking start position at time T1, the master controller 91 sends an operation command S1 including a brake command to the brake control device 21. When the start condition is met at time T1, the switching unit 52 outputs a stop signal S5, which stops the power conversion circuit 11, and from time T1 onwards the railway vehicle is decelerated by mechanical braking force.

[0058] 5 is completed, the speed acquisition unit 53 determines the speed of the railway vehicle from the measurement value of the speed sensor 94 (step S13). The speed acquisition unit 53 determines whether the railway vehicle is stopped or not based on the railway vehicle speed determined in step S13 (step S14). If the railway vehicle is not stopped, in other words, if the railway vehicle is moving (step S14; No), the processing of step S13 is repeated.

[0059] When the railway vehicle stops (step S14; Yes), the speed acquisition unit 53 sends the railway vehicle speed repeatedly obtained over the target period to the determination unit 54, and the determination unit 54 determines the actual deceleration of the railway vehicle over the target period from the railway vehicle speed obtained from the speed acquisition unit 53 (step S15). In detail, the determination unit 54 determines the actual deceleration using the above-mentioned formula (1). In the example of FIG. 6 , there is no change in the brake command over the time τ1 from time T1 to time T2, and the railway vehicle decelerates at a constant deceleration. The determination unit 54 sends the determined actual deceleration to the determination unit 42 of the deterioration determination device 41. When the processing of step S15 in FIG. 5 is completed, the above-mentioned processing is repeated from step S11.

[0060] The process of determining the degree of deterioration of the mechanical brake device 93, which is performed by the deterioration determination device 41 in accordance with the actual deceleration determined by the actual deceleration acquisition device 51 as described above, will be described with reference to Fig. 7. When the actual deceleration is determined by the actual deceleration acquisition device 51, the deterioration determination device 41 starts the process of Fig. 7.

[0061] The determination unit 42 calculates a deceleration difference, which is the difference between the actual deceleration acquired from the actual deceleration acquisition device 51 and the target deceleration indicated by the brake command included in the driving command S1 acquired from the master controller 91 (step S21). The determination unit 42 divides the deceleration difference calculated in step S21 by the target deceleration to calculate the ratio of the difference between the actual deceleration and the target deceleration to the target deceleration (step S22). The determination unit 42 determines whether the ratio calculated in step S22 is within the target range (step S23). If the ratio calculated in step S22 is not within the target range (step S23; No), the determination unit 42 outputs a deterioration determination result indicating that deterioration of the mechanical brake device 93 has occurred to the brake control unit 31 (step S24). In step S24, the determination unit 42 preferably outputs the ratio calculated in step S22 to the brake control unit 31 in addition to the deterioration determination result. When the processing of step S24 is completed, the deterioration determination device 41 ends the deterioration determination process.

[0062] If the ratio calculated in step S22 is within the target range (step S23; Yes), the determination unit 42 outputs a deterioration determination result indicating that there is no deterioration of the mechanical brake device 93 to the brake control unit 31 (step S25). When the process of step S25 is completed, the deterioration determination device 41 ends the deterioration determination process.

[0063] The brake control device 21 performs brake control based on the degree of deterioration of the mechanical brake device 93 determined by the deterioration determination device 41 as described above. The brake control process performed by the brake control device 21 will be described with reference to Fig. 8. When the railway vehicle starts operation, the brake control device 21 starts the process shown in Fig. 8.

[0064] The target braking force determination unit 32 determines whether the driving command S1 includes a braking command (step S31). While the driving command S1 does not include a braking command (step S31; No), the processing of step S31 is repeated. When the driving command S1 includes a braking command (step S31; Yes), the target braking force determination unit 32 calculates a target braking force by multiplying the target deceleration indicated by the braking command by the vehicle weight detected by the load compensation detector 92 (step S32). The target braking force determination unit 32 sends the target braking force calculated in step S32 to the regenerative control unit 33, the braking force adjustment unit 34, and the mechanical brake control unit 35.

[0065] The regeneration control unit 33 determines a target electric brake force from the target brake force calculated in step S32 (step S33). If the speed of the railway vehicle is within a speed range where a sufficient amount of regenerative braking can be obtained, the regeneration control unit 33 uses the target brake force as the target electric brake force. The regeneration control unit 33 sends a regeneration pattern S3 indicating the target electric brake force to the power conversion circuit control unit 12.

[0066] If the judgment result of the deterioration judgment device 41 indicates that deterioration has occurred in the mechanical brake device 93 (step S34; Yes), the brake force adjustment unit 34 adjusts the target brake force calculated in step S32 according to the ratio calculated by the judgment unit 42 (step S35).

[0067] If the determination result of the deterioration determination device 41 indicates that deterioration has occurred in the mechanical brake device 93 (step S34; Yes) and the actual electric brake force indicated by the regenerative feedback S4 is less than the target brake force calculated in step S32 (step S36; Yes), the mechanical brake control unit 35 determines the target mechanical brake force from the difference between the target brake force adjusted in step S35 and the actual electric brake force (step S37). For example, the mechanical brake control unit 35 uses the difference between the target brake force adjusted in step S35 and the actual electric brake force as the target mechanical brake force.

[0068] If the determination result of the deterioration determination device 41 indicates that the mechanical brake device 93 has not deteriorated (step S34; No) and the actual electric brake force indicated by the regenerative feedback S4 is less than the target brake force calculated in step S32 (step S38; Yes), the mechanical brake control unit 35 determines the target mechanical brake force from the difference between the target brake force calculated in step S32 and the actual electric brake force (step S39). For example, the mechanical brake control unit 35 uses the difference between the target brake force calculated in step S32 and the actual electric brake force as the target mechanical brake force.

[0069] The mechanical brake control unit 35 controls the mechanical brake device 93 in accordance with the target mechanical brake force determined in step S37 or step S39 (step S40). When the process of step S40 is completed, the above-described process is repeated from step S31.

[0070] If the determination result of the deterioration determination device 41 indicates that deterioration has occurred in the mechanical brake device 93 (step S34; Yes) and the actual electric brake force indicated by the regenerative feedback S4 is not less than the target brake force calculated in step S32, in other words, if the actual electric brake force indicated by the regenerative feedback S4 is equal to or greater than the target brake force calculated in step S32 (step S36; No), the mechanical brake control unit 35 does not operate the mechanical brake device 93, and the brake control device 21 repeats the above-mentioned processing from step S31.

[0071] If the determination result of the deterioration determination device 41 indicates that the mechanical brake device 93 has not deteriorated (step S34; No) and the actual electric brake force indicated by the regenerative feedback S4 is not less than the target brake force calculated in step S32, in other words, if the actual electric brake force indicated by the regenerative feedback S4 is equal to or greater than the target brake force calculated in step S32 (step S38; No), the mechanical brake control unit 35 does not operate the mechanical brake device 93, and the brake control device 21 repeats the above-mentioned processing from step S31.

[0072] As described above, a timing chart for explaining the operation of the brake control device 21, which acquires the actual deceleration of the railway vehicle, determines whether the mechanical brake device 93 has deteriorated, and performs brake control, is shown in Figure 9. As shown in graph A in Figure 9, T1 is the time when the railway vehicle reaches a braking start position just before a predetermined stop station and an operation command S1 including a brake command indicating a target deceleration α1 is input to the brake control device 21. At time T1, the start condition for the process of acquiring the actual deceleration is met, the switching unit 52 outputs a stop signal S5, and the power conversion circuit 11 stops. At time T1, the speed acquisition unit 53 acquires the speed V1 of the railway vehicle.

[0073] At time T1, it is assumed that the deterioration determination device 41 determines that there is no deterioration in the mechanical brake device 93. Therefore, as shown in graph E of FIG. 9 , the determination result signal output by the deterioration determination device 41 indicates an L level.

[0074] At time T1, when a brake command is input, the target braking force determination unit 32 of the brake control unit 31 determines the target braking force. The regenerative control unit 33 determines the target electric braking force according to the target braking force and sends a regeneration pattern S3 indicating the target electric braking force to the power conversion circuit control unit 12. Because the power conversion circuit control unit 12 has received the stop signal S5 from the switching unit 52 at time T1, it sends to the power conversion circuit 11 a power conversion control signal S2 that turns off multiple switching elements of the power conversion circuit 11 regardless of the regeneration pattern S3. For this reason, as shown in graph C in Figure 9, no electric braking force is generated. The power conversion circuit control unit 12 sends a regenerative feedback S4 to the brake control device 21, which indicates that no electric braking force is being generated.

[0075] As shown in graph E of FIG. 9, the discrimination result signal indicates an L level at time T1, so the braking force adjuster 34 sends the target braking force acquired from the target braking force determiner 32 to the mechanical brake controller 35.

[0076] Because the actual electric brake force is less than the target brake force obtained from the target brake force determination unit 32, the mechanical brake control unit 35 uses the difference between the target brake force obtained from the brake force adjustment unit 34 and the actual electric brake force as the target mechanical brake force. As described above, the target brake force obtained from the brake force adjustment unit 34 matches the target brake force determined by the target brake force determination unit 32. As the mechanical brake control unit 35 controls the mechanical brake device 93 in accordance with the target mechanical brake force, a mechanical brake force is generated and increases to a mechanical brake force MB1, as shown in graph D of Figure 9. As a result, the railway vehicle decelerates from time T1 onwards, as shown in graph B of Figure 9.

[0077] The time when the decelerating railway vehicle stops is defined as time T2. When the railway vehicle stops at time T2, determination unit 54 of actual deceleration acquisition device 51 determines the actual deceleration of the railway vehicle from the change in the railway vehicle speed during the target period from time T1 to time T2, based on the railway vehicle speed acquired by speed acquisition unit 53.

[0078] The determination unit 42 determines the degree of deterioration of the mechanical brake device 93 by comparing the actual deceleration acquired from the actual deceleration acquisition device 51 with the target deceleration indicated by the brake command. For example, if the ratio of the difference between the actual deceleration and the target deceleration to the target deceleration is not within the target range, the determination unit 42 outputs an H-level determination result signal to the brake control unit 31 of the brake control device 21, as shown in graph E in Figure 9.

[0079] The time when the railway vehicle that stopped at time T2 starts to accelerate is defined as T3. When the master controller 91 is operated at time T3 to instruct the railway vehicle to accelerate, the operation command S1 including the brake command is no longer input to the brake control device 21, and the brake control device 21 performs control to reduce the air pressure inside the brake cylinder of the mechanical brake device 93. As a result, as shown in graph D of Figure 9 , the mechanical brake force starts to decrease at time T3. As shown in graph B of Figure 9 , the railway vehicle starts to accelerate at time T3, and the speed of the railway vehicle increases until it reaches speed V1.

[0080] Thereafter, the master controller 91 is operated to instruct the railway vehicle to decelerate, and time T4 is defined as the time at which the start condition for the actual deceleration acquisition device 51 to acquire the actual deceleration is not satisfied at time T4. Therefore, the switching unit 52 does not send a stop signal S5 to the power conversion circuit control unit 12.

[0081] At time T4, when an operating command S1 including a brake command is input to the brake control device 21, a target braking force determination unit 32 of the brake control unit 31 determines a target braking force. A regeneration control unit 33 determines a target electric braking force according to the target braking force, and sends a regeneration pattern S3 indicating the target electric braking force to the power conversion circuit control unit 12. The power conversion circuit control unit 12 sends a power conversion control signal S2 according to the regeneration pattern S3 to the power conversion circuit 11.

[0082] A power conversion circuit 11, which has multiple switching elements controlled by a power conversion control signal S2, converts AC power supplied from the electric motor IM1 into DC power and charges a filter capacitor FC1 with the DC power. Power is supplied from the filter capacitor FC1 to other nearby powered railway cars via a power supply line, such as an overhead line, and the power generated by the electric motor IM1 operating as a generator is consumed. As a result, as shown in graph C of Figure 9 , the electric brake force begins to increase from time T4, generating an electric brake force EB1. As a result, at time T4, the railway car's speed begins to decrease from V1, as shown in graph B of Figure 9 .

[0083] The time when the actual electric brake force falls below the target brake force due to a decrease in the speed of the railway vehicle is defined as time T5. Until time T5, the actual electric brake force is equal to or greater than the target brake force, so no mechanical brake force is generated by the mechanical brake device 93.

[0084] 9 , the determination result signal indicates an H level at time T5, so the brake force adjuster 34 adjusts the target brake force acquired from the target brake force determiner 32 and sends the adjusted target brake force to the mechanical brake control unit 35. In detail, the brake force adjuster 34 adjusts the target brake force in accordance with the ratio acquired from the determination unit 42 of the deterioration determination device 41. For example, when sufficient brake force cannot be obtained due to deterioration of the mechanical brake device 93 and the ratio acquired from the determination unit 42 is a negative value, the brake force adjuster 34 adjusts the target brake force by multiplying the target brake force by the absolute value of the ratio and adding the result to the target brake force.

[0085] When, at time T5, the actual electric brake force becomes smaller than the target brake force determined by the target brake force determination unit 32, the mechanical brake control unit 35 uses the difference between the adjusted target brake force obtained from the brake force adjustment unit 34 and the actual electric brake force as the target mechanical brake force.

[0086] The mechanical brake control unit 35 controls the mechanical brake device 93 in accordance with the target mechanical brake force, thereby generating a mechanical brake force as shown in graph D of Fig. 9. The mechanical brake control unit 35 controls the mechanical brake device 93 in accordance with the target mechanical brake force according to the difference between the adjusted target brake force and the actual electric brake force, thereby causing the mechanical brake force generated by the mechanical brake device 93 to reach a mechanical brake force MB2 that is greater than the mechanical brake force MB1, as shown in graph D of Fig. 9.

[0087] As described above, the generation of mechanical braking force makes it possible to decelerate the railway vehicle at a constant deceleration even if the electric braking force decreases after time T5 as shown in graph C of Figure 9. As a result, the railway vehicle stops at time T6.

[0088] In control based on the difference between the target brake force determined in accordance with the target deceleration and the actual electric brake force, the obtained mechanical brake force is mechanical brake force MB1 because deterioration of the mechanical brake device 93 has occurred. As described above, when deterioration of the mechanical brake device 93 has occurred, the brake control unit 31 controls the mechanical brake device 93 using, as the target mechanical brake force, the difference between the target brake force adjusted in accordance with the ratio of the difference between the actual deceleration and the target deceleration to the target deceleration. As a result, a mechanical brake force MB2 greater than the mechanical brake force MB1 is obtained. This makes it possible to reduce the deviation between the actual deceleration and the target deceleration due to deterioration of the mechanical brake device 93.

[0089] As described above, the actual deceleration acquisition device 51 according to the first embodiment stops the power conversion circuit 11 and acquires the actual deceleration of the railway vehicle that is decelerating using only the mechanical braking force out of the mechanical braking force and the electric braking force. This enables the actual deceleration acquisition device 51 to acquire the actual deceleration of the railway vehicle due to the mechanical braking force.

[0090] The deterioration determination device 41 determines the degree of deterioration of the mechanical brake device 93 according to the actual deceleration of the railway vehicle due to the mechanical braking force, and therefore can accurately determine the degree of deterioration of the mechanical brake device 93.

[0091] The brake control device 21 performs brake control in accordance with the determination result of the deterioration determination device 41. In detail, when the deterioration determination device 41 determines that deterioration has occurred in the mechanical brake device 93, the brake control device 21 adjusts the target brake force, and controls the mechanical brake device 93 using the difference between the actual electric brake force and the target brake force adjusted in accordance with the ratio of the difference between the adjusted actual deceleration and the target deceleration to the target deceleration as the target mechanical brake force. This makes it possible to reduce the deviation between the actual deceleration and the target deceleration due to deterioration of the mechanical brake device 93.

[0092] (Embodiment 2) The actual deceleration acquisition device 51 may adjust the actual deceleration determined from the speed of the railway vehicle being decelerated by mechanical braking force in accordance with the external environment. In Embodiment 2, a brake control device 21 including an actual deceleration acquisition device 51 that adjusts the actual deceleration in accordance with the gradient of the running position of the railway vehicle will be described, focusing on the differences from Embodiment 1.

[0093] As shown in Figure 10, in addition to the configuration of the actual deceleration acquisition device 51 according to the first embodiment, the actual deceleration acquisition device 51 further includes a deceleration adjustment unit 55 that adjusts the actual deceleration determined by the determination unit 54 in accordance with the running position of the railway vehicle.

[0094] The switching unit 52 sends a notification to the speed acquisition unit 53 and the deceleration adjustment unit 55 that the stop signal S5 has been output.

[0095] When the speed acquired from the speed sensor 94 becomes zero, the speed acquisition unit 53 notifies the deceleration adjustment unit 55 that the railway vehicle has stopped.

[0096] When deceleration adjustment unit 55 receives a notification that stop signal S5 has been output from switching unit 52, it acquires information about the gradient of the running position of the railway vehicle from an ATO (Automatic Train Operation) device (not shown). Deceleration adjustment unit 55 repeats acquiring information about the gradient of the running position of the railway vehicle until it receives a notification from speed sensor 94 that the railway vehicle has stopped.

[0097] The deceleration adjustment unit 55 adjusts the actual deceleration determined by the determination unit 54 in accordance with the time from when the power conversion circuit 11 is stopped by the stop signal S5 to when the railway vehicle is stopped by receiving mechanical braking force, in other words, the gradient of the running position of the railway vehicle over the target period. The gradient of the running position of the railway vehicle over the target period is, for example, the average value of the gradient of the positions where the railway vehicle has traveled during the target period.

[0098] If the running position of the railway vehicle during the target period is on an upward gradient, the deceleration adjustment unit 55 makes an adjustment to increase the absolute value of the actual deceleration determined by the determination unit 54. If the running position of the railway vehicle during the target period is on a downward gradient, the deceleration adjustment unit 55 makes an adjustment to decrease the absolute value of the actual deceleration determined by the determination unit 54. The deceleration adjustment unit 55 sends the actual deceleration adjusted as described above to the determination unit 42.

[0099] For example, the deceleration adjustment unit 55 adjusts the actual deceleration by using the braking distance s' expressed by the following equation (3) instead of the braking distance s in the above equation (1). In the following equation (3), i indicates the gradient. If the gradient is an uphill gradient, i is a positive number, and if the gradient is a downhill gradient, i is a negative number.

[0100]

[0101] The determination unit 42 included in the deterioration determination device 41 determines the degree of deterioration of the mechanical brake device 93 based on the actual deceleration adjusted by the deceleration adjustment unit 55 .

[0102] Unlike in embodiment 1, the brake control unit 31 provided in the brake control device 21 of embodiment 2 controls the power conversion circuit control unit 12 and the mechanical brake device 93 in accordance with the adjusted target brake force when the deterioration determination device 41 determines that deterioration has occurred in the mechanical brake device 93.

[0103] 11, the configuration of the brake control unit 31 is the same as in embodiment 1. The target braking force determination unit 32 sends the target braking force determined in the same manner as in embodiment 1 to the braking force adjustment unit 34.

[0104] The braking force adjuster 34 adjusts the target braking force in accordance with the deterioration determiner 41. In particular, when the deterioration determiner 41 determines that the mechanical brake device 93 has not deteriorated, the braking force adjuster 34 sends the target braking force acquired from the target braking force determiner 32 to the regenerative control unit 33 and the mechanical brake control unit 35. When the determination unit 42 of the deterioration determiner 41 determines that the mechanical brake device 93 has deteriorated, the braking force adjuster 34 adjusts the target braking force in accordance with the ratio acquired from the determination unit 42 of the deterioration determiner 41, and sends the adjusted target braking force to the regenerative control unit 33 and the mechanical brake control unit 35.

[0105] The hardware configuration of the brake control device 21 is the same as that of Embodiment 1. The actual deceleration acquisition process performed by the actual deceleration acquisition device 51 having the above configuration will be described below with reference to Fig. 12. The actual deceleration acquisition device 51 starts the process shown in Fig. 12 when the railway vehicle starts operation. The process from steps S11 to S13 is the same as the process from steps S11 to S13 performed by the actual deceleration acquisition device 51 according to Embodiment 1 shown in Fig. 5.

[0106] The deceleration adjustment unit 55 acquires the gradient of the railway vehicle's running position (step S16). The speed acquisition unit 53 determines whether the railway vehicle is stopped or not based on the railway vehicle's speed determined in step S13 (step S14). While the railway vehicle is not stopped, in other words, while the railway vehicle is running (step S14; No), the processes of steps S13 and S16 are repeated.

[0107] When the railway vehicle stops (step S14; Yes), the determination unit 54 determines the actual deceleration of the railway vehicle for the target period from the speed of the railway vehicle acquired from the speed acquisition unit 53 (step S15). The deceleration adjustment unit 55 adjusts the actual deceleration determined in step S15 in accordance with the gradient of the railway vehicle's running position over the target period (step S17). When the processing of step S17 is completed, the processing from step S11 is repeated.

[0108] The operation of the deterioration determination process performed by the deterioration determination device 41 is the same as that in the first embodiment.

[0109] The brake control process by the brake control device 21 will be described with reference to Fig. 13. When the railway vehicle starts operation, the brake control device 21 starts the process shown in Fig. 13.

[0110] The target braking force determination unit 32 determines whether the driving command S1 includes a braking command (step S41). While the driving command S1 does not include a braking command (step S41; No), the processing of step S41 is repeated. If the driving command S1 includes a braking command (step S41; Yes), the target braking force determination unit 32 calculates the target braking force by multiplying the target deceleration indicated by the braking command by the vehicle weight detected by the load compensation detector 92 (step S42). The target braking force determination unit 32 sends the target braking force calculated in step S42 to the braking force adjustment unit 34.

[0111] If the determination result of the deterioration determination device 41 indicates that deterioration has occurred in the mechanical brake device 93 (step S43; Yes), the brake force adjuster 34 adjusts the target brake force calculated in step S42 in accordance with the ratio calculated by the determiner 42 (step S44). The brake force adjuster 34 sends the adjusted target brake force to the regeneration control unit 33 and the mechanical brake control unit 35.

[0112] The regeneration control unit 33 determines a target electric brake force from the target brake force adjusted in step S44 (step S45). If the speed of the railway vehicle is within a speed range where a sufficient amount of regenerative braking can be obtained, the regeneration control unit 33 uses the target brake force as the target electric brake force. The regeneration control unit 33 sends a regeneration pattern S3 indicating the target electric brake force to the power conversion circuit control unit 12.

[0113] If the actual electric brake force indicated by the regenerative feedback S4 is not less than the adjusted target brake force, in other words, if the actual electric brake force indicated by the regenerative feedback S4 is greater than or equal to the adjusted target brake force (step S46; No), the mechanical brake control unit 35 does not operate the mechanical brake device 93, and the brake control device 21 repeats the above-mentioned processing from step S41.

[0114] If the actual electric brake force is less than the adjusted target brake force (step S46; Yes), the mechanical brake control unit 35 determines the target mechanical brake force from the difference between the target brake force adjusted in step S44 and the actual electric brake force (step S47). For example, the mechanical brake control unit 35 uses the difference between the target brake force adjusted in step S44 and the actual electric brake force as the target mechanical brake force.

[0115] If the determination result of the deterioration determination device 41 indicates that the mechanical brake device 93 has not deteriorated (step S43; No), the brake force adjustment unit 34 does not perform the process of step S44. Therefore, the target brake force output by the brake force adjustment unit 34 and sent to the regeneration control unit 33 and the mechanical brake control unit 35 is the same as the target brake force calculated by the target brake force determination unit 32. If the determination result of the deterioration determination device 41 indicates that the mechanical brake device 93 has not deteriorated (step S43; No), the regeneration control unit 33 determines the target electric brake force from the target brake force calculated in step S42 (step S48). If the speed of the railway vehicle is within a speed range where sufficient regenerative braking can be obtained, the regeneration control unit 33 uses the target brake force as the target electric brake force. The regeneration control unit 33 sends a regeneration pattern S3 indicating the target electric brake force to the power conversion circuit control unit 12.

[0116] If the actual electric braking force indicated by the regenerative feedback S4 is not less than the target braking force calculated in the braking force step S42, in other words, if the actual electric braking force indicated by the regenerative feedback S4 is greater than or equal to the target braking force calculated in step S42 (step S49; No), the mechanical brake control unit 35 does not operate the mechanical brake device 93, and the brake control device 21 repeats the above-mentioned processing from step S41.

[0117] If the actual electric brake force is less than the target brake force calculated in step S42 (step S49; Yes), the mechanical brake control unit 35 determines the target mechanical brake force from the difference between the target brake force calculated in step S42 and the actual electric brake force (step S50). For example, the mechanical brake control unit 35 uses the difference between the target brake force calculated in step S42 and the actual electric brake force as the target mechanical brake force.

[0118] The mechanical brake control unit 35 controls the mechanical brake device 93 in accordance with the target mechanical brake force determined in step S47 or step S50 (step S51). When the process of step S51 is completed, the above-described process is repeated from step S41.

[0119] 14 is a timing chart illustrating the operation of the brake control device 21, which acquires the actual deceleration of the railway vehicle, determines whether the mechanical brake device 93 has deteriorated, and performs brake control, as described above. The operation of the brake control device 21 up to time T4 is the same as the operation of the brake control device 21 shown in FIG.

[0120] At time T4, when the driving command S1 including a brake command is input to the brake control device 21, the target braking force determination unit 32 of the brake control unit 31 determines a target braking force. At time T4, as shown in graph E in Figure 14, the discrimination result signal indicates an H level, so the braking force adjustment unit 34 adjusts the target braking force in accordance with the ratio calculated by the discrimination unit 42 and sends the adjusted target braking force to the regeneration control unit 33 and the mechanical brake control unit 35. For example, when sufficient braking force cannot be obtained due to deterioration of the mechanical brake device 93 and the ratio obtained from the discrimination unit 42 is a negative value, the braking force adjustment unit 34 adjusts the target braking force by multiplying the target braking force by the absolute value of the ratio and adding the result to the target braking force.

[0121] The regeneration control unit 33 determines a target electric brake force in accordance with the adjusted target brake force and sends a regeneration pattern S3 indicating the target electric brake force to the power conversion circuit control unit 12. The power conversion circuit control unit 12 sends a power conversion control signal S2 in accordance with the regeneration pattern S3 to the power conversion circuit 11. As a result, as shown in graph C of FIG. 14 , the electric brake force begins to increase from time T4, and an electric brake force EB2 is generated. Because control was performed using the target electric brake force based on the target brake force adjusted to a large value in accordance with deterioration of the mechanical brake device 93, the electric brake force EB2 is greater than the electric brake force EB1 generated in the first embodiment. Time T5 is the time when the actual electric brake force falls below the adjusted target brake force due to a decrease in the speed of the railway vehicle. The operation of the brake control device 21 from time T5 onwards is the same as in the first embodiment.

[0122] As described above, the actual deceleration acquisition device 51 according to the second embodiment stops the power conversion circuit 11, acquires the actual deceleration of the railway vehicle being decelerated by the mechanical braking force, and adjusts the actual deceleration in accordance with the gradient at which the railway vehicle is traveling. This enables the actual deceleration acquisition device 51 to accurately acquire the actual deceleration of the railway vehicle due to the mechanical braking force.

[0123] The deterioration determination device 41 determines the degree of deterioration of the mechanical brake device 93 based on the actual deceleration of the railway vehicle due to the mechanical braking force, which is adjusted according to the gradient of the railway vehicle's running position, and therefore can accurately determine the degree of deterioration of the mechanical brake device 93.

[0124] The brake control device 21 performs brake control in accordance with the determination result of the deterioration determination device 41. In particular, when the deterioration determination device 41 determines that deterioration has occurred in the mechanical brake device 93, the brake control device 21 adjusts the target brake force and determines the target electric brake force and the target mechanical brake force in accordance with the adjusted target brake force. This makes it possible to reduce the deviation between the actual deceleration and the target deceleration due to deterioration of the mechanical brake device 93.

[0125] Third Embodiment The method for determining the degree of deterioration of the mechanical brake device 93 is not limited to the above example. A deterioration determination device 41 having a method for determining deterioration different from those of the first and second embodiments will be described in a third embodiment, focusing on the differences from the first and second embodiments.

[0126] The configuration of the deterioration determination device 41 according to the third embodiment is the same as that according to the first embodiment. A determination unit 42 included in the deterioration determination device 41 according to the third embodiment acquires the actual deceleration of the other railway vehicle from an actual deceleration acquisition device included in a deterioration determination device included in a brake control device mounted on the other railway vehicle. The determination unit 42 determines the degree of deterioration of the mechanical brake device 93 by comparing the actual deceleration acquired from the actual deceleration acquisition device 51 with the actual deceleration of the other railway vehicle. In detail, the determination unit 42 determines whether an actual deceleration difference, which is the difference between the actual deceleration acquired from the actual deceleration acquisition device 51 and the actual deceleration of the other railway vehicle, is within a target range, which is an allowable range for the braking performance of the mechanical brake device 93. If the actual deceleration difference is within the target range, it can be determined that the mechanical brake device 93 has not deteriorated. If the actual deceleration difference is not within the target range, it can be determined that the mechanical brake device 93 has deteriorated.

[0127] The process of determining the degree of deterioration of the mechanical brake device 93 performed by the deterioration determination device 41 in accordance with the actual deceleration determined by the actual deceleration acquisition device 51 as described above will be described with reference to Fig. 15. The deterioration determination device 41 starts the process of Fig. 15 when the actual deceleration is determined by the actual deceleration acquisition device 51 and the actual deceleration of another railway vehicle is acquired.

[0128] The determination unit 42 calculates an actual deceleration difference, which is the difference between the actual deceleration acquired from the actual deceleration acquisition device 51 and the actual deceleration of the other railway vehicle (step S61). The determination unit 42 determines whether the actual deceleration difference calculated in step S61 is within a target range (step S62). If the actual deceleration difference calculated in step S61 is not within the target range (step S62; No), the determination unit 42 outputs a deterioration determination result indicating that deterioration of the mechanical brake device 93 has occurred to the brake control unit 31 (step S63). Specifically, the determination unit 42 outputs an H-level determination result signal to the brake control unit 31.

[0129] If the actual deceleration difference calculated in step S61 is within the target range (step S62; Yes), the determination unit 42 outputs a deterioration determination result indicating that there is no deterioration of the mechanical brake device 93 to the brake control unit 31 (step S64). Specifically, the determination unit 42 outputs an L-level determination result signal to the brake control unit 31. When the processes of steps S63 and S64 are completed, the deterioration determination process ends.

[0130] As described above, the deterioration determination device 41 according to embodiment 3 determines the degree of deterioration of the mechanical brake device 93 based on the difference between the actual deceleration of the railway vehicle due to the mechanical braking force and the actual deceleration of other railway vehicles, and is therefore able to accurately determine the degree of deterioration of the mechanical brake device 93.

[0131] The present disclosure is not limited to the above-described exemplary embodiments. The above-described exemplary embodiments can be combined in any manner. The brake control device 21 according to the first exemplary embodiment may perform brake control similar to that of the brake control device 21 according to the second exemplary embodiment. The brake control device 21 according to the first exemplary embodiment may perform deterioration determination processing similar to that of the deterioration determination device 41 according to the third exemplary embodiment.

[0132] To improve the accuracy of the deterioration determination, as shown in FIG. 16 , the determination unit 42 may determine whether the ratio is repeatedly outside the target range. The processes of steps S21 to S25 in FIG. 16 are the same as the processes of steps S21 to S25 performed by the deterioration determination device 41 according to the first embodiment shown in FIG. 7 . If it is determined in step S23 that the ratio calculated in step S22 is outside the target range (step S23; No), the determination unit 42 stores the ratio and the corresponding date and time in a storage device (not shown) (step S26). If the ratio calculated in step S22 is within the target range (step S23; Yes), the process of step S26 is not performed.

[0133] The determination unit 42 determines whether the number of ratios stored in the storage device is equal to or greater than a threshold value (step S27). If the number of ratios stored in the storage device is equal to or greater than the threshold value (step S27; Yes), the determination unit 42 outputs a deterioration determination result indicating that deterioration has occurred in the mechanical brake device 93 to the brake control unit 31 (step S24). If the number of ratios stored in the storage device is less than the threshold value (step S27; No), the determination unit 42 outputs a deterioration determination result indicating that deterioration has not occurred in the mechanical brake device 93 to the brake control unit 31 (step S25).

[0134] The brake control device 21 may stop the process of determining the degree of deterioration when an abnormality occurs in brake control in order to improve the accuracy of determining the degree of deterioration of the mechanical brake device 93. As an example, the determination unit 54 of the actual deceleration acquisition device 51 may stop the actual deceleration acquisition process when the time from when the start condition is satisfied until the railway vehicle stops is not within a predetermined time, for example, an allowable range of the time required from the braking start position to the station. In this case, the deterioration determination device 41 does not acquire the actual deceleration and therefore does not perform the deterioration determination process.

[0135] The brake control device 21 may stop the process of determining the degree of deterioration when slide control is performed in order to improve the accuracy of determining the degree of deterioration of the mechanical brake device 93. As an example, the decision unit 54 of the actual deceleration acquisition device 51 may stop the actual deceleration acquisition process if the measurement value of the speed sensor 94 suddenly decreases from the time the start condition is met until the railway vehicle comes to a stop. In this case, the deterioration determination device 41 does not acquire the actual deceleration and therefore does not perform the deterioration determination process.

[0136] In order to improve the accuracy of determining the degree of deterioration of the mechanical brake device 93, the brake control device 21 may use an average value of the actual deceleration to determine the degree of deterioration of the mechanical brake device 93. In particular, the determination unit 42 may determine the average value of the actual deceleration acquired by the actual deceleration acquisition device 51 at different times for the same target deceleration, and determine the degree of deterioration of the mechanical brake device 93 based on whether the ratio of the difference between the average value of the actual deceleration and the target deceleration to the target deceleration is within a target range.

[0137] When the ratio acquired from the determination unit 42 is a positive value, the braking force adjustment unit 34 may adjust the target braking force by multiplying the target braking force by the absolute value of the ratio and subtracting the result from the target braking force. The method of adjusting the target braking force by the braking force adjustment unit 34 is not limited to the above example, and any method can be used as long as it can compensate for fluctuations in the mechanical braking force due to deterioration of the mechanical brake device 93.

[0138] The start condition for the process of acquiring the actual deceleration performed by the actual deceleration acquisition device 51 is not limited to the above example. For example, the process of acquiring the actual deceleration may be started when the railway vehicle reaches any point through which the railway vehicle passes.

[0139] The end timing of the target period is not limited to the timing when the railway vehicle stops, and may be any timing. As one example, the end timing of the target period may be when the speed of the railway vehicle reaches a predetermined speed. As another example, the length of the target period may be predetermined. In other words, the target period may be from when the start condition for the process of obtaining the actual deceleration is met until a predetermined time has elapsed.

[0140] The process of determining the actual deceleration in the determiner 54 of the actual deceleration acquisition device 51 is not limited to the example described above. As an example, the determiner 54 may determine the actual deceleration by dividing the railway vehicle's speed at the start and end of the target period by the length of the target period. In this case, the speed acquirer 53 of the actual deceleration acquisition device 51 may acquire the time each time the railway vehicle's speed is determined in step S13 of FIG. 5 , and store the determined railway vehicle speed in the storage device in association with the time. In the example of FIG. 6 , the determiner 54 may determine the actual deceleration by dividing the speed difference (−V1) by the length τ1 from time T1 to time T2.

[0141] The electric braking force is not limited to regenerative braking, but may be braking force generated by dynamic braking.

[0142] In the above embodiment, normal brake control has been described, but even during emergency brake control, the pressure of the air output by the emergency solenoid valve used for emergency brake control may be adjusted depending on the degree of deterioration of the mechanical brake device 93.

[0143] In the above-described embodiment, the target deceleration indicated by the brake command is constant during the target period in which the actual deceleration acquisition process is performed, but the brake command may change during the target period. As shown in Figure 17, when the target deceleration indicated by the brake command changes, the determination unit 42 calculates the target deceleration for the target period from time T11 to time T14 based on the target deceleration α1 from time T11 to time T12, the target deceleration α2 from time T12 to time T13, and the target deceleration α3 from time T13 to time T14. The determination unit 42 determines the degree of deterioration of the mechanical brake device 93 from the actual deceleration acquired by the actual deceleration acquisition device 51 and the target deceleration calculated as described above.

[0144] The determination unit 42 may transmit the determination result and the ratio of the difference between the actual deceleration and the target deceleration to the target deceleration to the integrated train management device. The integrated train management device may analyze signs of deterioration of the mechanical brake device 93 based on, for example, the ratio of the difference between the actual deceleration and the target deceleration to the target deceleration.

[0145] The deterioration determination device 41 may be provided as a device independent of the brake control device 21. In this case, the determination result of the deterioration determination device 41 may be sent to the brake control device 21, or may be sent to, for example, a display device provided in the driver's cab, a vehicle control system at a depot, or the like without being sent to the brake control device 21.

[0146] The deterioration determination device 41 may be realized as an on-board device installed in a railway vehicle independent of the brake control device 21, or may be realized as one function of the train integrated management device.

[0147] The switching unit 52 may be implemented as one function of the ATO device. The switching unit 52 may output the stop signal S5 in response to an operation of an operation switch provided in the driver's cab.

[0148] The speed acquisition unit 53 of the actual deceleration acquisition device 51 may obtain the position of the railway vehicle using radio waves from GPS (Global Positioning System) satellites, and determine the speed of the railway vehicle from the amount of change in the position of the railway vehicle per unit time.

[0149] The power conversion device 1 may be mounted on an AC-fed railway vehicle. In this case, a transformer that steps down the voltage of AC power supplied from a current collector and a converter that converts the AC power stepped down by the transformer into DC power may be provided. The power conversion device 1 converts the DC power supplied from the converter into AC power and supplies the converted AC power to the electric motor IM1.

[0150] The hardware configuration of the brake control device 21 is not limited to the above example. As shown in Fig. 18 , the brake control device 21 may be realized by a processing circuit 84. The processing circuit 84 is connected to a main controller 91, a power conversion circuit control unit 12, a load compensation detector 92, a mechanical brake device 93, and a speed sensor 94 via an interface circuit 85.

[0151] When the processing circuit 84 is dedicated hardware, the processing circuit 84 includes, for example, a single circuit, a composite circuit, a processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), or a combination thereof. Each unit of the brake control device 21 may be realized by an individual processing circuit 84 or may be realized by a common processing circuit 84.

[0152] Some of the functions of the brake control device 21 may be realized by dedicated hardware, and other functions may be realized by software or firmware. For example, in the brake control device 21, the components of the actual deceleration acquisition device 51 may be realized by a processing circuit 84 shown in Fig. 18, and the determination unit 42 and the brake control unit 31 may be realized by a processor 81 shown in Fig. 4 reading and executing a program stored in a memory 82.

[0153] The present disclosure allows various embodiments and modifications without departing from the broad spirit and scope of the present disclosure. Furthermore, the above-described embodiments are intended to illustrate the present disclosure and do not limit the scope of the present disclosure. That is, the scope of the present disclosure is defined by the claims, not the embodiments. Various modifications made within the scope of the claims and the meaning of equivalent disclosures are considered to be within the scope of the present disclosure.

[0154] 1 Power conversion device, 1a, 1b Terminal, 11 Power conversion circuit, 12 Power conversion circuit control unit, 21 Brake control device, 31 Brake control unit, 32 Target braking force determination unit, 33 Regeneration control unit, 34 Brake force adjustment unit, 35 Mechanical brake control unit, 41 Deterioration determination device, 42 Determination unit, 51 Actual deceleration acquisition device, 52 Switching unit, 53 Speed ​​acquisition unit, 54 Determination unit, 55 Deceleration adjustment unit, 80 Bus, 81 Processor, 82 Memory, 83 Interface, 84 Processing circuit, 85 Interface circuit, 91 Main controller, 92 Load response detector, 93 Mechanical brake device, 94 Speed ​​sensor, FC1 Filter capacitor, IM1 Electric motor, S1 Operation command, S2 Power conversion control signal, S3 Regeneration pattern, S4 Regeneration feedback, S5 Stop signal.

Claims

1. An actual deceleration acquisition device comprising: a speed acquisition unit that acquires the speed of a railway vehicle over a target period in a state in which the railway vehicle is decelerating by receiving driving force from an electric motor that rotates when supplied with electric power and by receiving at least one of a mechanical braking force from a mechanical braking device and an electric braking force generated by consuming electric power generated by the electric motor operating as a generator; and a determination unit that determines the actual deceleration of the railway vehicle over the target period from the change in speed acquired by the speed acquisition unit.

2. An actual deceleration acquisition device as described in claim 1, further comprising a switching unit that stops the power conversion of a power conversion circuit that converts the power supplied from the electric motor operating as a generator and outputs the converted power, and the speed acquisition unit acquires the speed of the railway vehicle over the target period after the switching unit stops the power conversion of the power conversion circuit.

3. The actual deceleration acquisition device according to claim 2, wherein the switching unit stops the power conversion of the power conversion circuit in response to a brake command instructing the railway vehicle to decelerate.

4. The actual deceleration acquisition device according to claim 2 or 3, wherein the switching unit stops the power conversion of the power conversion circuit depending on the running position of the railway vehicle.

5. An actual deceleration acquisition device as described in any one of claims 1 to 4, wherein the speed acquisition unit acquires the speed of the railway vehicle over the target period in which the target deceleration can be considered constant, while the railway vehicle is decelerating by receiving only the mechanical braking force in accordance with the target deceleration indicated by a brake command that instructs the railway vehicle to decelerate.

6. An actual deceleration acquisition device according to any one of claims 1 to 5, wherein the target period is a period from when the railway vehicle reaches a predetermined position until when the railway vehicle stops.

7. An actual deceleration acquisition device according to any one of claims 1 to 6, further comprising a deceleration adjustment unit that adjusts the actual deceleration determined by the determination unit in accordance with the gradient of the running position of the railway vehicle during the target period.

8. A deterioration determination device comprising: an actual deceleration acquisition device according to any one of claims 1 to 6; and a determination unit that acquires the actual deceleration determined by the determination unit of the actual deceleration acquisition device from the determination unit, and determines the degree of deterioration of the mechanical brake device from the acquired actual deceleration.

9. A deterioration determination device comprising: an actual deceleration acquisition device according to claim 7; and a determination unit that acquires the actual deceleration adjusted by the deceleration adjustment unit from the deceleration adjustment unit of the actual deceleration acquisition device, and determines the degree of deterioration of the mechanical brake device from the acquired actual deceleration.

10. A deterioration determination device as described in claim 8 or 9, wherein the determination unit determines the degree of deterioration of the mechanical brake device by comparing the acquired actual deceleration with a target deceleration indicated by a brake command that instructs the railway vehicle to decelerate.

11. The deterioration determination device according to claim 10, wherein the determination unit determines the degree of deterioration of the mechanical brake device based on whether or not the ratio of the difference between the acquired actual deceleration and the target deceleration to the target deceleration is within a target range.

12. A deterioration determination device as claimed in any one of claims 8 to 10, wherein the determination unit determines an average value of the acquired actual deceleration, and determines the degree of deterioration of the mechanical brake device based on whether the ratio of the difference between the average value and a target deceleration indicated by a brake command instructing the railway vehicle to decelerate is within a target range.

13. A deterioration determination device as described in claim 8, wherein the determination unit obtains the actual deceleration of the other railway vehicle determined from the determination unit of the other actual deceleration acquisition device that determines the actual deceleration of the other railway vehicle, and determines the degree of deterioration of the mechanical brake device by comparing the actual deceleration of the railway vehicle obtained from the determination unit with the actual deceleration of the other railway vehicle obtained from the determination unit of the other actual deceleration acquisition device.

14. A brake control device comprising: a deterioration determination device according to any one of claims 8 to 13; and a brake control unit that controls a power conversion circuit control unit that converts the power supplied from the mechanical brake device and the electric motor operating as a generator and outputs the converted power, in accordance with the target deceleration indicated by a brake command instructing the railway vehicle to decelerate and the determination result of the deterioration determination device.

15. A brake control device as described in claim 14, wherein the brake control unit comprises: a target brake force determination unit that determines a target brake force in accordance with the target deceleration; a brake force adjustment unit that adjusts the target brake force in accordance with the determination result of the deterioration determination device; a regeneration control unit that determines a target electric brake force in accordance with the target brake force adjusted by the brake force adjustment unit, and sends a regeneration pattern indicative of the target electric brake force to the power conversion circuit control unit; and a mechanical brake control unit that obtains regeneration feedback indicative of an actual electric brake force from the power conversion circuit control unit, determines a target mechanical brake force from the target brake force adjusted by the brake force adjustment unit and the actual electric brake force, and controls the mechanical brake device in accordance with the target mechanical brake force.

16. A brake control device as described in claim 14, wherein the brake control unit comprises: a target brake force determination unit that determines a target brake force in accordance with the target deceleration; a regeneration control unit that determines a target electric brake force in accordance with the target brake force and sends a regeneration pattern indicative of the target electric brake force to the power conversion circuit control unit; a brake force adjustment unit that adjusts the target brake force in accordance with the determination result of the deterioration determination device; and a mechanical brake control unit that obtains regeneration feedback indicative of an actual electric brake force from the power conversion circuit control unit, and, if the actual electric brake force is less than the target brake force determined by the target brake force determination unit, determines a target mechanical brake force from the target brake force adjusted by the brake force adjustment unit and the actual electric brake force, and controls the mechanical brake device in accordance with the target mechanical brake force.

17. A method for obtaining an actual deceleration, comprising the steps of: acquiring the speed of a railway vehicle that accelerates by receiving driving force from an electric motor that rotates when supplied with electric power, and decelerating by receiving at least one of a mechanical braking force from a mechanical braking device and an electric braking force generated by consuming electric power generated by the electric motor operating as a generator, over a target period while decelerating by receiving only the mechanical braking force, without receiving the electric braking force of either the mechanical braking force or the electric braking force; and determining the actual deceleration of the railway vehicle during the target period from the change in the acquired speed.

18. A method for determining deterioration, comprising the steps of: acquiring the speed of a railway vehicle that accelerates by receiving driving force from an electric motor that rotates when supplied with electricity, and decelerating by receiving at least one of mechanical braking force from a mechanical braking device and electric braking force generated by consuming electricity generated by the electric motor operating as a generator, while decelerating by receiving only the mechanical braking force and not the electric braking force from either the mechanical braking force or the electric braking force, determining the actual deceleration of the railway vehicle during the target period from the change in speed obtained; and determining the degree of deterioration of the mechanical braking device from the determined actual deceleration.

19. A brake control method comprising the steps of: acquiring the speed of a railway vehicle that accelerates by receiving driving force from an electric motor that rotates when supplied with electric power, and decelerating by receiving at least one of mechanical braking force from a mechanical braking device and electric braking force generated by consuming electric power generated by the electric motor operating as a generator, while decelerating by receiving only the mechanical braking force and not the electric braking force from either the mechanical braking force or the electric braking force, determining an actual deceleration of the railway vehicle during the target period from the acquired change in speed, determining a degree of deterioration of the mechanical braking device from the determined actual deceleration, converting the power supplied from the mechanical braking device and the electric motor operating as a generator in accordance with a target deceleration indicated in a brake command instructing the railway vehicle to decelerate and the determined degree of deterioration of the mechanical braking device, and controlling a power conversion circuit that outputs the converted power.

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