Brake control system and brake control method

A brake control system comprising:

• target braking force calculating circuitry to calculate a target braking force for causing a railway vehicle to decelerate in accordance with a braking instruction containing a normal braking instruction or an emergency braking instruction, the normal braking instruction designating a normal deceleration indicating a target value of deceleration of the railway vehicle, the emergency braking instruction designating an emergency deceleration indicating a target value of deceleration of the railway vehicle greater than a maximum value of the normal deceleration;
• target pressure calculating circuitry to calculate a target pressure based on the target braking force, the target pressure indicating a target value of pressure of fluid to be fed to a mechanical brake device in order to activate the mechanical brake device, the mechanical brake device being configured to press a friction member against a rotating body and thereby cause the railway vehicle to decelerate, the friction member being configured to move depending on a pressure of the fed fluid, the rotating body being configured to rotate during running of the railway vehicle;
• an output valve to compress fluid fed from a fluid source in accordance with the target pressure and feed the compressed fluid to the mechanical brake device;
• and
• compensation controlling circuitry to execute control for compensating for a gap between an actual braking force and the target braking force when the braking instruction contains the emergency braking instruction, the actual braking force indicating an existing braking force generated in the railway vehicle, wherein the control for compensating for the gap is not executed when the braking instruction does not contain the emergency braking instruction, wherein
• the compensation controlling circuitry comprises
• determining circuitry to determine whether compensation is necessary for the gap between the actual braking force and the target braking force, and
• compensating circuitry to compensate for the gap between the actual braking force and the target braking force, when the determining circuitry determines that compensation is necessary for the gap between the actual braking force and the target braking force,
• the railway vehicle
• accelerates by receiving a driving force from a motor, the motor being configured to rotate in response to feeding of electric power fed from a power source and converted by a power conversion apparatus, and
• decelerates by receiving at least either of an electric braking force and a mechanical braking force generated by the mechanical brake device, the electric braking force being generated by consumption of electric power, the electric power fed from the motor functioning as an electric generator and converted by the power conversion apparatus,
• the brake control system further comprises regenerative brake controlling circuitry, the regenerative brake controlling circuitry being configured to
• calculate a target electric braking force indicating a target value of the electric braking force based on the target braking force,
• transmit the target electric braking force to power conversion apparatus controlling circuitry and thereby induce generation of the electric braking force, the power conversion apparatus controlling circuitry being configured to control the power conversion apparatus in accordance with the target electric braking force, and
• acquire, from the power conversion apparatus controlling circuitry, an actual electric braking force indicating an existing electric braking force, and
• the target pressure calculating circuitry subtracts the actual electric braking force from the target braking force, and thereby calculates a target mechanical braking force indicating a target value of the mechanical brake force, and calculates the target pressure based on the target mechanical braking force, and
• the compensating circuitry
• calculates a target electric braking force based on the target braking force, when the determining circuitry determines that compensation is necessary for the gap between the actual braking force and the target braking force, and
• determines the target electric braking force to be 0 regardless of the target braking force, when the determining circuitry determines that no compensation is necessary for the gap between the actual braking force and the target braking force, and
• when the braking instruction contains the emergency braking instruction, the regenerative brake controlling circuitry transmits the target electric braking force calculated by the compensating circuitry to the power conversion apparatus controlling circuitry.

A brake control method of controlling brake, the method comprising:

• calculating a target braking force for causing a railway vehicle to decelerate in accordance with a braking instruction containing a normal braking instruction or an emergency braking instruction, the normal braking instruction designating a normal deceleration indicating a target value of deceleration of the railway vehicle, the emergency braking instruction designating an emergency deceleration indicating a target value of deceleration of the railway vehicle greater than a maximum value of the normal deceleration;
• calculating a target pressure based on the target braking force, the target pressure indicating a target value of pressure of fluid inside a brake cylinder included in a mechanical brake device;
• controlling the mechanical brake device in accordance with the target pressure;
• and
• executing control for compensating for a gap between an actual braking force and the target braking force by adjusting the target pressure while the emergency braking instruction is being input, the actual braking force indicating an existing braking force generated in the railway vehicle, wherein the control for compensating for the gap is not executed when the emergency braking instruction is not input.