Fluid control system, braking system, and anomaly detection system

Abstract

The control system continues even if a malfunction occurs in the sensor used for feedback control. [Solution] The fluid control system comprises a device for controlling the fluid flowing through a channel, a first sensor provided upstream of the device, and a second sensor provided downstream of the device. The fluid control system performs processing based on the measured value of a reference sensor, which is one of the first and second sensors. The fluid control system comprises an abnormality detection unit, an estimation unit, and a processing unit. The abnormality detection unit determines whether or not there is an abnormality in the reference sensor. The estimation unit calculates an estimated value of the measured value from the reference sensor based on the measured values ​​from the first and second sensors, which is not the reference sensor, according to the characteristics of the device. The processing unit performs processing using the estimated value if it is determined that there is an abnormality in the reference sensor.

Description

Technical Field

[0001] The present invention relates to a fluid control system, a brake system, and an abnormality determination system.

Background Art

[0002] Railway vehicles employ air brakes. Patent Document 1 describes feedback control of air brakes. Patent Document 1 discloses a technique for feedback control such that the output pressure of a solenoid valve (service control valve) that generates the pilot pressure of the air brake matches the pressure indicated by a pressure command signal.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Since the feedback control described in Patent Document 1 is feedback control based on the pilot pressure of the air brake, control becomes impossible when an abnormality occurs in the sensor that detects the pilot pressure. Not only in air brakes, but also in systems that control fluids by feedback control, control may become impossible due to sensor abnormalities. An object of the present invention is to provide a fluid control system, a brake system, and an abnormality determination system that can continue control even when an abnormality occurs in a sensor used for feedback control.

Means for Solving the Problems

[0005] According to the first embodiment, the fluid control system includes: a device for controlling fluid flowing through a flow path; a first sensor provided upstream of the device in the flow path and measuring state quantities relating to the fluid flowing into the device; a second sensor provided downstream of the device in the flow path and measuring state quantities relating to the fluid flowing out of the device; a processing unit that performs processing based on the measured values ​​of a reference sensor, which is one of the first sensor and the second sensor; an abnormality determination unit that determines whether or not there is an abnormality in the reference sensor; and an estimation unit that calculates an estimated value of the measured value by the reference sensor from the measured values ​​of the first sensor and the second sensor that is not the reference sensor, based on the characteristics of the device, wherein the processing unit performs the processing using the estimated value when it is determined that there is an abnormality in the reference sensor.

[0006] According to the second embodiment, in the fluid control system according to the first embodiment, the fluid control system may be provided in a railway vehicle, and the processing unit may control the brakes of the railway vehicle based on the measured value or the estimated value.

[0007] According to the third embodiment, in the fluid control system according to the first or second embodiment, the fluid may be air, and the state quantities measured by the first sensor and the second sensor may be the pressure or flow rate of the air.

[0008] According to the fourth aspect, in a fluid control system according to any of the first to third aspects, the device may be a valve.

[0009] According to the fifth aspect, in the fluid control system according to the fourth aspect, the device may be a flow amplification valve.

[0010] According to the sixth aspect, the brake system is a brake system provided on a railway vehicle and comprises: an air brake that is operated by air supplied from an air source through a flow path; a pilot pressure generating unit provided in the flow path and generating pilot pressure for the air brake using air supplied from the air source; a valve provided in the flow path between the pilot pressure generating unit and the air brake; a first sensor provided in the flow path between the valve and the pilot pressure generating unit and measuring the state amount of air flowing into the valve; a second sensor provided in the flow path between the valve and the air brake and measuring the state amount of air flowing out of the valve; a processing unit that performs feedback control of the pilot pressure generating unit based on the measured value of a reference sensor which is one of the first sensor and the second sensor and the target pressure of the air brake; an abnormality determination unit that determines whether or not there is an abnormality in the reference sensor; and an estimation unit that calculates an estimated value of the measured value by the reference sensor from the measured value of a sensor which is not the reference sensor which is one of the first sensor and the second sensor, based on the characteristics of the valve, wherein the processing unit performs the feedback control using the estimated value when it is determined that there is an abnormality in the reference sensor.

[0011] According to the seventh aspect, in the brake system according to the sixth aspect, the abnormality determination unit may determine that the abnormality of the reference sensor has disappeared when the difference between the measured value of the reference sensor and the estimated value remains below a threshold for a predetermined period of time, and the processing unit may perform processing based on the measured value of the reference sensor after it has been determined that the abnormality of the reference sensor has disappeared.

[0012] According to the eighth aspect, the brake system according to the sixth or seventh aspect may include a notification unit that notifies of an abnormality when the abnormality determination unit determines that there is an abnormality in the reference sensor.

[0013] According to the ninth aspect, the abnormality determination system comprises a valve unit comprising: a device for controlling fluid flowing through a flow path; a first sensor provided upstream of the device in the flow path and measuring a state quantity relating to the fluid flowing into the device; and a second sensor provided downstream of the device in the flow path and measuring the state quantity relating to the fluid flowing out of the device; an estimation unit that calculates an estimated value of the measured value of the other sensor from the measured value of one of the first and second sensors based on the characteristics of the device; and an abnormality determination unit that determines whether or not there is an abnormality in the valve unit based on the difference between the measured value of the other sensor and the estimated value of the other sensor.

[0014] According to the tenth embodiment, a brake system provided in a railway vehicle includes: an air brake that is operated by air supplied from an air source through a flow path; a pilot pressure generating unit provided in the flow path that generates pilot pressure for the air brake using air supplied from the air source; a valve provided in the flow path between the pilot pressure generating unit and the air brake; a first sensor provided in the flow path between the valve and the pilot pressure generating unit that measures the pressure of air flowing into the valve; a second sensor provided in the flow path between the valve and the air brake that measures the pressure of air flowing out of the valve; an estimation unit that calculates an estimated value of the measured value of the other sensor from the measured value of one of the first and second sensors based on the characteristics of the valve; and an abnormality determination unit that determines whether or not there is an abnormality in the valve unit based on the difference between the measured value of the other sensor and the estimated value of the other sensor. [Effects of the Invention]

[0015] According to at least one of the above embodiments, the fluid control system, the brake system, and the abnormality detection system can continue control even if an abnormality occurs in the sensor used for feedback control. [Brief explanation of the drawing]

[0016] [Figure 1] It is a schematic diagram showing the configuration of the brake system according to the first embodiment. [Figure 2] It is a schematic block diagram showing the configuration of the controller according to the first embodiment. [Figure 3] It is a flowchart showing the control method (part 1) of the brake system according to the first embodiment. [Figure 4] It is a flowchart showing the control method (part 2) of the brake system according to the first embodiment. [Figure 5] It is a schematic block diagram showing the configuration of the brake system according to the second embodiment. [Figure 6] It is a flowchart showing the method for determining an abnormality of the air brake by the controller according to the second embodiment.

MODE FOR CARRYING OUT THE INVENTION

[0017] (First Embodiment) Hereinafter, embodiments will be described in detail with reference to the drawings.

[0018] <Configuration of Brake System> FIG. 1 is a schematic diagram showing the configuration of the brake system according to the first embodiment. The brake system 1 according to the first embodiment is provided on a railway vehicle. The brake system 1 includes an air tank 101, a service control valve 102, a plurality of air springs 103, a load-responsive valve 104, an emergency solenoid valve 105, a relay valve 106, a brake cylinder 107, a brake setter 108, an AC pressure sensor 109, a BC pressure sensor 110, a plurality of load-responsive sensors 111, and a controller 112.

[0019] The air tank 101 is an air source that holds compressed air generated by a compressor (not shown). The service control valve 102 receives a control signal from the controller 112 and generates pilot air by releasing a portion of the compressed air supplied from the air tank 101 in accordance with the control signal, thereby reducing the pressure. The pressure of the pilot air is also called the AC (Application Chamber) pressure. The service control valve 102 supplies the pilot air to the relay valve 106. The service control valve 102 is an example of a pilot pressure generation unit.

[0020] The air spring 103 is installed in the underfloor of the railway vehicle. The internal air pressure of the air spring 103 changes in response to the applied load. In other words, the air pressure of the air spring 103 corresponds to the load. The air spring 103 is connected to a load-sensitive valve 104, and the air pressure of the air spring is transmitted to the load-sensitive valve 104. The load-sensitive valve 104 receives the air pressure from multiple air springs 103, changes the pressure of the compressed air supplied from the air tank 101 to a pressure that matches the load, and supplies it to the emergency solenoid valve 105. The emergency solenoid valve 105 switches whether or not to supply compressed air supplied from the load-sensitive valve 104 to the relay valve 106. The emergency solenoid valve 105 is electrically connected to the emergency brake command line and is controlled by the emergency brake command.

[0021] The relay valve 106 adjusts the pressure of the compressed air supplied from the air tank 101 to match the AC pressure output from the service control valve 102, and supplies it to the brake cylinder 107. The relay valve 106 is an example of a device that controls the fluid flowing through a flow path. The flow rate of the compressed air (control air) supplied by the relay valve 106 is greater than the flow rate of the pilot air supplied by the service control valve 102. In other words, the relay valve 106 is a flow amplification valve that generates control air with amplified flow rate while maintaining the pressure of the pilot air. The pressure of the control air output by the relay valve 106 is also called the BC (Brake Cylinder) pressure. Furthermore, when compressed air is supplied from the emergency solenoid valve 105, the relay valve 106 supplies control air in accordance with the pressure of the compressed air supplied from the emergency solenoid valve 105, regardless of the AC pressure.

[0022] The relay valve 106 has two air chambers (AC chamber and BC chamber) separated by a diaphragm. The AC chamber is provided with a pilot port into which pilot air flows. The BC chamber is provided with a first port communicating with the air tank 101 and a second port communicating with the brake cylinder 107. The pressure in the AC chamber is maintained at the AC pressure by the pilot air, and the diaphragm is pushed so that the pressures in the BC chamber and the AC chamber are balanced. Due to this configuration, the BC pressure is close to the AC pressure. Note that the structure of the relay valve 106 in other embodiments is not limited to that described above, but the common point is that the pressure between the air chamber into which pilot air flows and the air chamber out which control air flows is controlled to be balanced. Note that BC pressure and AC pressure do not perfectly match, and BC pressure P BC and AC pressure P AC This has the following relationship using gain A and offset B, given by equation (1). Equation (1) represents the characteristics of the relay valve 106. P BC =A×P AC +B …(1)

[0023] The brake cylinder 107 is operated by the pressure of the control air supplied from the relay valve 106, which operates a caliper brake (not shown). The operation of the caliper brake generates a braking force on the railway vehicle. The brake setter 108 is an operating device used by the train driver to instruct the target deceleration of the train. By operating the brake setter 108, a brake command indicating the target deceleration is input to the controller 112.

[0024] The AC pressure sensor 109 measures the AC pressure output from the normal control valve 102 and generates an electrical signal with a voltage corresponding to the AC pressure. The AC pressure sensor 109 is located upstream of the relay valve 106 in the flow path and is an example of a first sensor that measures state quantities related to the pilot air flowing into the relay valve 106. The AC pressure sensor 109 is an example of a reference sensor used for feedback control of the air brake. A reference sensor is a sensor whose measured value is referenced for processing performed by the controller 112. The BC pressure sensor 110 measures the BC pressure output from the relay valve 106 and generates an electrical signal with a voltage corresponding to the BC pressure. The BC pressure sensor 110 is an example of a second sensor installed downstream of the relay valve 106 in the flow path and measures state quantities related to the control air flowing out from the relay valve 106. The load-sensitive sensor 111 measures the air pressure of the air spring 103 and generates an electrical signal with a voltage corresponding to the air pressure. Since the air pressure corresponds to the load, the electrical signal output by the load-sensitive sensor 111 represents the load.

[0025] The controller 112 outputs a control signal to control the opening degree of the service control valve 102 based on the target deceleration indicated by the brake command from the brake setter 108 and the electrical signals input from the AC pressure sensor 109, BC pressure sensor 110, and load sensor 111.

[0026] <Controller 112 of Brake System 1> In the first embodiment, the controller 112 controls the brake cylinder 107 by feedback control using the AC pressure sensor 109. On the other hand, if an abnormality occurs in the AC pressure sensor 109, availability can be improved by controlling the brake cylinder 107 using the BC pressure sensor 110 instead of the AC pressure sensor 109. If an abnormality occurs in both the AC pressure sensor 109 and the BC pressure sensor 110, the brake cylinder 107 will be activated by the emergency solenoid valve 105.

[0027] Figure 2 is a schematic block diagram showing the configuration of the controller 112 according to the first embodiment. The controller 112 according to the first embodiment includes a signal input unit 201, a sensor abnormality determination unit 202, a conversion unit 203, a brake force determination unit 204, a feedback control unit 205, a signal output unit 206, a brake abnormality determination unit 207, a state storage unit 208, and a notification unit 209.

[0028] The signal input unit 201 receives electrical signals from the brake setter 108, AC pressure sensor 109, BC pressure sensor 110, and load sensor 111. The sensor abnormality determination unit 202 determines whether there is an abnormality in the AC pressure sensor 109, the BC pressure sensor 110, and the load sensor 111 based on the electrical signals input from the AC pressure sensor 109, the BC pressure sensor 110, and the load sensor 111. In the first embodiment, the sensor abnormality determination unit 202 determines whether there is a wire break or a short circuit in the sensor. Specifically, the sensor abnormality determination unit 202 determines a wire break if the voltage value of the electrical signal falls below the wire break threshold (e.g., 0.5V), and determines a short circuit if the voltage value of the electrical signal exceeds the short circuit threshold (e.g., 4.8V).

[0029] The conversion unit 203 converts the measured value of the BC pressure sensor 110 (BC pressure output from the relay valve 106) to the value of the AC pressure sensor 109 (AC pressure input to the relay valve 106) based on the above formula (1). The brake force determination unit 204 determines a target brake force to achieve a constant deceleration based on electrical signals from the brake setter 108 and the load sensor 111. Specifically, the brake force determination unit 204 determines the target brake force by multiplying the deceleration set by the brake setter 108 and the load measured by the load sensor 111. The brake force determination unit 204 then determines the target AC pressure from the target brake force.

[0030] The feedback control unit 205 calculates a correction value (feedback amount) related to feedback control so that the difference between the AC pressure indicated by the AC pressure sensor 109, or the AC pressure calculated from the BC pressure sensor 110, and the previous command value of the normal control valve 102 is minimized.

[0031] The signal output unit 206 outputs a control signal for the normal control valve 102 based on a value obtained by subtracting the feedback amount from the target AC pressure determined by the brake force determination unit 204.

[0032] The brake abnormality determination unit 207 compares the BC pressure required to exert the target braking force with the BC pressure indicated by the BC pressure sensor 110 and determines whether there is an abnormality related to insufficient air pressure or failure to release in the air brake. For example, the brake abnormality determination unit 207 determines that there is insufficient air pressure if the BC pressure indicated by the BC pressure sensor 110 remains below the insufficient air threshold for a certain period of time or longer. Also, for example, the brake abnormality determination unit 207 determines that there is a failure to release if the BC pressure indicated by the BC pressure sensor 110 remains above the failure to release threshold for a certain period of time or longer.

[0033] The state memory unit 208 stores the operating state of the feedback control. The operating state of the feedback control takes one of two values: "normal," which is the state in which feedback control is performed using the AC pressure sensor 109, or "emergency," which is the state in which feedback control is performed using the value of the AC pressure sensor 109 calculated from the BC pressure sensor 110. The initial value of the operating state stored in the state memory unit 208 is "normal."

[0034] The notification unit 209 notifies the driver of any abnormality detected in the AC pressure sensor 109, BC pressure sensor 110, or load sensor 111. The notification unit 209 notifies the driver of the abnormality, for example, by sounding a buzzer or illuminating a lamp.

[0035] <Control method for brake system 1> Figure 3 is a flowchart of the control method (Part 1) of the brake system 1 according to the first embodiment. Figure 4 is a flowchart of the control method (Part 2) of the brake system 1 according to the first embodiment. According to the first embodiment, when the brake system 1 is activated, the controller 112 repeatedly executes the process shown in Figure 3 at predetermined control cycles.

[0036] First, the signal input unit 201 of the controller 112 receives electrical signals from the brake setter 108, AC pressure sensor 109, BC pressure sensor 110, and load sensor 111 (step S1). The sensor abnormality determination unit 202 determines whether or not there is an abnormality in each of the AC pressure sensor 109, BC pressure sensor 110, and load sensor 111 based on the electrical signals input from them (step S2). If it is determined that there is an abnormality in any of the AC pressure sensor 109, BC pressure sensor 110, or load sensor 111, the notification unit 209 notifies the driver of the abnormality.

[0037] The brake force determination unit 204 determines a target AC pressure to achieve the desired target brake force based on electrical signals from the brake setter 108 and the load sensor 111 (step S3). If there is a malfunction in the load sensor 111, the brake force determination unit 204 determines the target AC pressure using a predetermined guaranteed load value.

[0038] Next, the sensor abnormality determination unit 202 determines whether the operating state value stored in the state memory unit 208 is "normal" (step S18). If the operating state value is "normal" (step S18: YES), the sensor abnormality determination unit 202 determines whether or not an abnormality was determined in step S2 for the AC pressure sensor 109 (step S5). If it is determined that there is no abnormality in the AC pressure sensor 109 (step S5: NO), the feedback control unit 205 calculates the feedback amount so that the difference between the AC pressure indicated by the measured value of the AC pressure sensor 109 and the previous command value of the normal control valve 102 becomes small (step S6).

[0039] On the other hand, if it is determined in step S2 that there is an abnormality in the AC pressure sensor 109 (step S5: YES), the sensor abnormality determination unit 202 determines whether or not it was determined that there was an abnormality in the BC pressure sensor 110 (step S7). If it is determined in step S2 that there is no abnormality in the BC pressure sensor 110 (step S7: NO), the sensor abnormality determination unit 202 rewrites the operating status stored in the state memory unit 208 to "emergency" (step S8). The conversion unit 203 converts the measured value of the BC pressure sensor 110 to AC pressure based on the above formula (1) (step S9). The feedback control unit 205 calculates the feedback amount so that the difference between the converted value of the AC pressure and the previous command value of the normal control valve 102 is small (step S10).

[0040] In step S18, if the value of the operating status is "emergency" (step S18: NO), the conversion unit 203 converts the measured value of the BC pressure sensor 110 to AC pressure based on the above formula (1) (step S11). Next, the sensor abnormality determination unit 202 determines whether or not an abnormality was determined in step S2 for the AC pressure sensor 109 (step S12). If the AC pressure sensor 109 is determined to be abnormal (step S12: YES), the sensor abnormality determination unit 202 determines whether or not the BC pressure sensor 110 was determined to be abnormal (step S13). If the BC pressure sensor 110 is determined to be normal (step S13: NO), the feedback control unit 205 calculates the feedback amount so that the difference between the converted value of the AC pressure obtained in step S11 and the previous command value of the normal control valve 102 becomes small (step S14).

[0041] If the AC pressure sensor 109 is determined to be normal (step S12: NO), the sensor abnormality determination unit 202 determines whether the difference between the measured value of the AC pressure sensor 109 and the converted value of the AC pressure calculated in step S11 has remained within a predetermined range for a certain period of time (step S15). If the difference between the measured value of the AC pressure and the converted value of the AC pressure exceeds the predetermined range within a certain period of time (step S15: NO), the sensor abnormality determination unit 202 maintains the operating state in "emergency" mode because the AC pressure sensor 109 may not be stable. The controller 112 proceeds to step S13. On the other hand, if the difference between the measured AC pressure and the converted AC pressure does not exceed a predetermined range for a certain period of time (step S15: YES), the AC pressure sensor 109 is considered stable, and the sensor abnormality determination unit 202 rewrites the operating state stored in the state memory unit 208 to "normal" (step S16). The controller 112 proceeds to step S6.

[0042] When the feedback amount is calculated in step S6, step S10, or step S14, the signal output unit 206 outputs a control signal for the normal control valve 102 based on the value obtained by subtracting the feedback amount from the target AC pressure determined in step S3 (step S17).

[0043] If both the AC pressure sensor 109 and the BC pressure sensor 110 are found to be abnormal (step S7: YES, or step S13: YES), the feedback control unit 205 cannot determine the feedback amount, and therefore the signal output unit 206 does not output a control signal for the normal control valve 102 (step S18).

[0044] The above-described order of processing is merely an example, and the order of some processing steps may be changed, or the calculations may be performed in parallel. For example, in the first embodiment, the conversion from BC pressure to AC pressure in step S7 is performed only if there is no abnormality in the BC pressure sensor 110, but in other embodiments, it may be performed before determining whether or not there is an abnormality in the sensor, or regardless of the determination result.

[0045] <Effects> As described above, the brake system 1 according to the first embodiment performs feedback control of the AC pressure based on the measured value from the AC pressure sensor 109 (reference sensor) located upstream of the relay valve 106. If there is a malfunction in the AC pressure sensor 109, the controller 112 of the brake system 1 performs feedback control of the AC pressure using the value of the AC pressure sensor 109 estimated from the measured value of the BC pressure sensor 110. As a result, even if there is a malfunction in the AC pressure sensor 109, the controller 112 can continue to control the brakes using the BC pressure sensor 110. Therefore, the controller 112 according to the first embodiment can improve the availability of the brake system 1.

[0046] In the first embodiment, the brake system 1 includes an AC pressure sensor 109 and a BC pressure sensor 110, which are pressure sensors for measuring air pressure, but other embodiments are not limited to this. For example, the brake system 1 in other embodiments may be equipped with a flow sensor instead of a pressure sensor.

[0047] (Second embodiment) In the first embodiment, the controller 112 estimates the value of the AC pressure sensor 109 from the measured value of the BC pressure sensor 110 in order to improve the availability of AC pressure feedback control. In contrast, the controller 112 in the second embodiment estimates the value of the BC pressure sensor 110 from the measured value of the AC pressure sensor 109. When an abnormality occurs in the BC pressure sensor 110, the controller 112 in the second embodiment uses the BC pressure value estimated from the measured value of the AC pressure sensor 109 to determine whether there is insufficient air pressure or failure to release the air brake.

[0048] Figure 5 is a schematic block diagram showing the configuration of the brake system 1 according to the second embodiment. In addition to the configuration of the first embodiment, the brake system 1 according to the second embodiment further includes a relay valve sensor 113 that determines whether or not there is a malfunction in the relay valve 106. The brake abnormality determination unit 207 of the controller 112 determines whether there is an abnormality in the air brake based on the measured value of the BC pressure sensor 110 if there is no abnormality in the BC pressure sensor 110. On the other hand, if there is an abnormality in the BC pressure sensor 110, the brake abnormality determination unit 207 determines whether there is an abnormality in the air brake based on the BC pressure estimated from the measured value of the AC pressure sensor 109 and the measured value of the relay valve sensor 113.

[0049] Figure 6 is a flowchart showing the method for determining abnormalities in the air brake by the controller 112 according to the second embodiment. In the second embodiment, the controller 112 of the brake system 1 repeatedly executes the process shown in Figure 6 at predetermined control cycles when the brake system 1 is activated.

[0050] First, the signal input unit 201 of the controller 112 receives electrical signals from the brake setter 108, the AC pressure sensor 109, and the BC pressure sensor 110 (step S21). The sensor abnormality determination unit 202 determines whether or not there is an abnormality in the AC pressure sensor 109 and the BC pressure sensor 110, based on the electrical signals input from the AC pressure sensor 109 and the BC pressure sensor 110 (step S22). If it is determined that there is an abnormality in any of the AC pressure sensor 109, the BC pressure sensor 110, or the load sensor 111, the notification unit 209 notifies the driver of the abnormality.

[0051] The sensor abnormality determination unit 202 determines whether or not an abnormality was determined in the BC pressure sensor 110 in step S2 (step S23). If it is determined that there is no abnormality in the BC pressure sensor 110 (step S23: NO), the brake abnormality determination unit 207 determines whether or not there is an abnormality in the air brake, i.e., insufficient air or failure to release, based on the BC pressure indicated by the measured value of the BC pressure sensor 110 (step S24).

[0052] On the other hand, if it is determined in step S22 that there is an abnormality in the BC pressure sensor 110 (step S23: YES), the sensor abnormality determination unit 202 determines whether or not it was determined that there was an abnormality in the AC pressure sensor 109 (step S25). If it is determined that there is no abnormality in the AC pressure sensor 109 (step S25: NO), the conversion unit 203 converts the measured value of the AC pressure sensor 109 to BC pressure based on the above formula (1) (step S26). The brake abnormality determination unit 207 determines whether or not there is an abnormality in the air brake based on the BC pressure converted from the measured value of the AC pressure sensor 109 and the measured value of the relay valve sensor 113 (step S27). Specifically, if the brake abnormality determination unit 207 determines from the measured value of the relay valve sensor 113 that there is an abnormality in the relay valve 106 (air leak, sticking, etc.), it determines that there is an abnormality in the air brake. Furthermore, the brake abnormality determination unit 207 determines that there is an abnormality in the air brake if the difference between the BC pressure calculated from the AC pressure sensor 109 and the BC pressure required to exert the desired braking force exceeds a predetermined range.

[0053] If the result of step S24 or step S27 indicates a brake abnormality (step S28: YES), the notification unit 209 notifies the driver of the brake abnormality (step S29). If both the AC pressure sensor 109 and the BC pressure sensor 110 are malfunctioning, the notification unit 209 notifies the driver that it is not possible to determine if there is a brake malfunction (step S30).

[0054] <Effects> As described above, the controller 112 of the brake system 1 according to the second embodiment determines brake abnormalities based on the measured value from the BC pressure sensor 110 (reference sensor) located downstream of the relay valve 106. If there is an abnormality in the BC pressure sensor 110, the controller 112 of the brake system 1 determines brake abnormalities using the BC pressure value estimated from the measured value of the AC pressure sensor 109. As a result, even if there is an abnormality in the BC pressure sensor 110, the controller 112 can continue to determine brake abnormalities using the AC pressure sensor 109. Therefore, the controller 112 according to the second embodiment can improve the availability of the brake system 1.

[0055] (Third embodiment) The controller 112 of the brake system 1 according to the above embodiment determines open-circuit and short-circuit faults based on whether the voltage value of the electrical signal from the AC pressure sensor 109 and BC pressure sensor 110 falls below the open-circuit threshold and whether it exceeds the short-circuit threshold. However, this method makes it difficult to detect faults where the voltage value of the electrical signal is stuck between the open-circuit threshold and the short-circuit threshold, or faults where an abnormal offset is added to the voltage value of the electrical signal. The third embodiment makes it possible to detect abnormalities other than open-circuit and short-circuit faults.

[0056] The configuration of the brake system 1 according to the third embodiment is the same as that of the first embodiment. The sensor abnormality determination unit 202 according to the third embodiment determines whether or not there is a sensor abnormality by comparing the measured value of the AC pressure sensor 109 with the AC pressure value converted from the measured value of the BC pressure sensor 110 by the conversion unit 203. Specifically, the sensor abnormality determination unit 202 determines that there is an abnormality in the valve unit consisting of the AC pressure sensor 109, the relay valve 106, and the BC pressure sensor 110 if the difference between the measured value of the AC pressure sensor 109 and the AC pressure value converted from the measured value of the BC pressure sensor 110 exceeds a predetermined range for a certain period of time. The valve unit subject to the above determination refers to the range of the pneumatic circuit constituting the brake system 1 from the location where the AC pressure sensor 109 is installed to the location where the BC pressure sensor 110 is installed.

[0057] The sensor abnormality determination unit 202 may also determine whether or not there is a sensor abnormality by comparing the measured value of the BC pressure sensor 110 with the BC pressure value converted from the measured value of the AC pressure sensor 109 by the conversion unit 203.

[0058] Furthermore, if the brake system 1 is equipped with a relay valve sensor 113, similar to the second embodiment, the sensor abnormality determination unit 202 may determine the abnormality based on the measured value of the relay valve sensor 113. When a relay valve sensor 113 is provided, the sensor abnormality determination unit 202 can distinguish between an abnormality in the AC pressure sensor 109 or BC pressure sensor 110 and an abnormality in the relay valve 106.

[0059] (Other embodiments) Although one embodiment has been described in detail above with reference to the drawings, the specific configuration is not limited to that described above, and various design changes are possible. In other embodiments, the order of the above-described processes may be changed as appropriate. Also, some processes may be executed in parallel. In the embodiments disclosed herein, those in which multiple functions are provided in a distributed manner may have some or all of those multiple functions integrated into a single unit, and conversely, those in which multiple functions are provided in a single unit may have some or all of those functions distributed into a single unit. Regardless of whether the functions are integrated or distributed, it is sufficient that the configuration achieves the objective of the invention. For example, the controller 112 according to the embodiments disclosed herein may be composed of a single computer, or the configuration of the controller 112 may be divided among multiple computers, and the multiple computers may cooperate with each other to function as the controller 112.

[0060] In the embodiments described above, the controller 112, i.e., the fluid controller, controls the air brake, but is not limited to this. For example, the fluid controller in other embodiments may control an actuator related to a hydraulic circuit. Furthermore, the controller 112 according to the above embodiment uses two sensors provided upstream and downstream of the relay valve 106 to perform processing such as feedback control of the air brake and abnormality detection of the air brake. In contrast, the controller 112 according to other embodiments may perform predetermined processing using two sensors provided upstream and downstream of equipment other than the relay valve 106 (for example, a valve, pump, actuator, etc.).

[0061] (Computer configuration) The controller 112 is equipped with a processor, memory, and auxiliary storage device connected by a bus, and functions as a device comprising a signal input unit 201, a sensor abnormality detection unit 202, a conversion unit 203, a brake force determination unit 204, a feedback control unit 205, a signal output unit 206, a brake abnormality detection unit 207, a state storage unit 208, and a notification unit 209 by executing a program. Examples of processors include a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), and a microprocessor. The program may be recorded on a computer-readable recording medium. Computer-readable recording media include, for example, magnetic disks, magneto-optical disks, optical disks, and semiconductor memory. The program may also be transmitted via a telecommunications line. Furthermore, all or part of the functions of the controller 112 may be implemented using custom LSIs (Large Scale Integrated Circuits) such as ASICs (Application Specific Integrated Circuits) or PLDs (Programmable Logic Devices). Examples of PLDs include PALs (Programmable Array Logic), GALs (Generic Array Logic), CPLDs (Complex Programmable Logic Devices), and FPGAs (Field Programmable Gate Arrays). Such integrated circuits are also included as examples of processors. [Explanation of symbols]

[0062] 1...Brake system 101...Air tank 102...Normal control valve 103...Air spring 104...Load-sensitive valve 105...Emergency solenoid valve 106...Relay valve 107...Brake cylinder 108...Brake setter 109...AC pressure sensor 110...BC pressure sensor 111...Load-sensitive sensor 112...Controller 113...Relay valve sensor 201...Signal input unit 202...Sensor abnormality detection unit 203...Conversion unit 204...Brake force determination unit 205...Feedback control unit 206...Signal output unit 207...Brake abnormality detection unit 208...State memory unit 209...Notification unit

Claims

1. Equipment for controlling the fluid flowing through a channel, A first sensor is provided upstream of the device in the aforementioned flow path and measures state quantities related to the fluid flowing into the device, A second sensor is provided downstream of the device in the aforementioned flow path and measures the state quantity relating to the fluid flowing out of the device, A processing unit that performs processing based on the measured value of a reference sensor, which is one of the first sensor and the second sensor, An abnormality determination unit that determines whether or not there is an abnormality in the reference sensor, An estimation unit calculates an estimated value of the measurement value by the reference sensor from the measurement values ​​of the first sensor and the second sensor (excluding the reference sensor) based on the characteristics of the aforementioned equipment, Equipped with, The processing unit, when it determines that there is an abnormality in the reference sensor, performs the processing using the estimated value. Fluid control system.

2. The aforementioned fluid control system is installed in a railway vehicle. The processing unit controls the brakes of the railway vehicle based on the measured value or the estimated value. The fluid control system according to claim 1.

3. The fluid is air, The state quantities measured by the first sensor and the second sensor are the air pressure or flow rate. The fluid control system according to claim 1.

4. The aforementioned device is a valve. The fluid control system according to claim 1.

5. The aforementioned device is a flow amplification valve. The fluid control system according to claim 4.

6. A braking system installed on a railway vehicle, An air brake that operates using air supplied from an air source through a channel, A pilot pressure generating unit is provided in the aforementioned flow path and generates pilot pressure for the air brake using air supplied from the air source, A valve provided between the pilot pressure generating unit and the air brake in the aforementioned flow path, A first sensor is provided in the aforementioned flow path between the valve and the pilot pressure generating unit, and measures the state of the air flowing into the valve. A second sensor is provided in the aforementioned flow path between the valve and the air brake, and measures the state amount of air flowing out from the valve. A processing unit that performs feedback control of the pilot pressure generation unit based on the measured value of a reference sensor, which is one of the first and second sensors, and the target pressure of the air brake, An abnormality determination unit that determines whether or not there is an abnormality in the reference sensor, An estimation unit calculates an estimated value of the measurement value by the reference sensor from the measurement value by the sensor that is not the reference sensor, which is one of the first sensor and the second sensor, based on the characteristics of the valve. Equipped with, The processing unit, when it determines that there is an abnormality in the reference sensor, performs the feedback control using the estimated value. Brake system.

7. The abnormality determination unit determines that the abnormality of the reference sensor has disappeared when the difference between the measured value of the reference sensor and the estimated value remains below a threshold for a predetermined period of time. The processing unit performs processing based on the measured values ​​of the reference sensor after it has determined that the abnormality of the reference sensor has been resolved. The brake system according to claim 6.

8. The system includes a notification unit that notifies of an abnormality if the abnormality detection unit determines that there is an abnormality in the reference sensor. The brake system according to claim 6.

9. A valve unit comprising: a device for controlling the fluid flowing through a flow path; a first sensor provided upstream of the device in the flow path for measuring state quantities relating to the fluid flowing into the device; and a second sensor provided downstream of the device in the flow path for measuring state quantities relating to the fluid flowing out of the device. An estimation unit calculates an estimated value of the measurement value from the other sensor of the first and second sensors based on the characteristics of the aforementioned device, An abnormality determination unit determines whether or not there is an abnormality in the valve unit based on the discrepancy between the measured value of the other sensor and the estimated value of the other sensor. An anomaly detection system equipped with the following features.

10. A braking system installed on a railway vehicle, An air brake that operates using air supplied from an air source through a channel, A pilot pressure generating unit is provided in the aforementioned flow path and generates pilot pressure for the air brake using air supplied from the air source, A valve unit comprising: a valve provided in the flow path between the pilot pressure generating unit and the air brake; a first sensor provided in the flow path between the valve and the pilot pressure generating unit for measuring the pressure of air flowing into the valve; and a second sensor provided in the flow path between the valve and the air brake for measuring the pressure of air flowing out of the valve. An estimation unit calculates an estimated value of the measurement value from the other sensor of the first and second sensors based on the characteristics of the valve, An abnormality determination unit determines whether or not there is an abnormality in the valve unit based on the discrepancy between the measured value of the other sensor and the estimated value of the other sensor. A braking system equipped with [specific features / features].

Images