Dynamometer system

A dynamometer system that includes:

• a test piece which has an input shaft and an output shaft, a dynamometer which is connected to any one of the input shaft or the output shaft through a coupling shaft, an inverter which supplies electric power to the dynamometer according to a torque current command signal, an angular speed sensor which generates an angular speed detection signal corresponding to an angular speed of the dynamometer, a shaft torque sensor which generates a shaft torque detection signal corresponding to a shaft torque occurring in the coupling shaft, and an electric inertia control device that simulates a behavior of an inertial body having predetermined set inertia by the dynamometer, the electric inertia control device comprising:
• an inertia compensator which generates an inertia compensation torque signal that simulates the inertial body based on a higher-level command torque signal, the shaft torque detection signal, and a ratio of an inertia of the dynamometer to the set inertia;
• a resonance suppression control circuit which generates the torque current command signal so as to suppress resonance inherent in the coupling shaft among resonances of a mechanical system that includes the test piece and the dynamometer by using the inertia compensation torque signal and the shaft torque detection signal;
• and
• a disturbance observer which generates a disturbance compensation torque signal that compensates for a deviation caused by a disturbance based on an estimation signal obtained by using the inertia compensator and the angular speed detection signal,
• wherein the inertia compensator generates a pre-conversion torque signal by summing the disturbance compensation torque signal and a difference between the shaft torque detection signal and the higher-level command torque signal, and generates the inertia compensation torque signal by summing the shaft torque detection signal and a product of the pre-conversion torque signal and the ratio, and
• the disturbance observer generates the disturbance compensation torque signal by subtracting, from the pre-conversion torque signal, a product of the derivative of the angular speed detection signal and the set inertia.

A dynamometer system that includes:

• a test piece which has an input shaft and an output shaft, a dynamometer which is connected to any one of the input shaft or the output shaft through a coupling shaft, an inverter which supplies electric power to the dynamometer according to a torque current command signal, an angular speed sensor which generates an angular speed detection signal corresponding to an angular speed of the dynamometer, a shaft torque sensor which generates a shaft torque detection signal corresponding to a shaft torque occurring in the coupling shaft, and an electric inertia control device that simulates a behavior of an inertial body having predetermined set inertia by the dynamometer, the electric inertia control device comprising:
• an inertia compensator which generates an inertia compensation torque signal that simulates the inertial body based on a higher-level command torque signal, the shaft torque detection signal, and a ratio of an inertia of the dynamometer to the set inertia;
• a resonance suppression control circuit which generates the torque current command signal so as to suppress resonance inherent in the coupling shaft among resonances of a mechanical system that includes the test piece and the dynamometer by using the inertia compensation torque signal and the shaft torque detection signal;
• and
• a disturbance observer which generates a disturbance compensation torque signal that compensates for a deviation caused by a disturbance based on an estimation signal obtained by using the inertia compensator and the angular speed detection signal,
• wherein the inertia compensator generates a post-conversion torque signal by multiplying a difference between the higher-level command torque and the shaft torque detection signal by the ratio, and generates the inertia compensation torque signal by summing the post-conversion torque signal, the disturbance compensation torque signal and the shaft torque detection signal, and
• the disturbance observer generates an angular speed signal by subtracting the angular speed detection signal from a product of the integral of the post-conversion torque signal and a reciprocal of the inertia of the dynamometer, and generates the disturbance compensation torque signal by multiplying the angular speed signal by a product of the inertia of the dynamometer and a predetermined gain.

A dynamometer system that includes:

• a test piece which has an input shaft and an output shaft, a dynamometer which is connected to any one of the input shaft or the output shaft through a coupling shaft, an inverter which supplies electric power to the dynamometer according to a torque current command signal, an angular speed sensor which generates an angular speed detection signal corresponding to an angular speed of the dynamometer, a shaft torque sensor which generates a shaft torque detection signal corresponding to a shaft torque occurring in the coupling shaft, and an electric inertia control device that simulates a behavior of an inertial body having predetermined set inertia by the dynamometer, the electric inertia control device comprising:
• an inertia compensator which generates an inertia compensation torque signal that simulates the inertial body based on a higher-level command torque signal, the shaft torque detection signal, and a ratio of an inertia of the dynamometer to the set inertia;
• a resonance suppression control circuit which generates the torque current command signal so as to suppress resonance inherent in the coupling shaft among resonances of a mechanical system that includes the test piece and the dynamometer by using the inertia compensation torque signal and the shaft torque detection signal;
• and
• a disturbance observer which generates a disturbance compensation torque signal that compensates for a deviation caused by a disturbance based on an estimation signal obtained by using the inertia compensator and the angular speed detection signal,
• wherein the inertia compensator generates a pre-conversion torque signal by summing the disturbance compensation torque signal and a difference between the shaft torque detection signal and the higher-level command torque signal, and generates the inertia compensation torque signal by summing the shaft torque detection signal and a product of the pre-conversion torque signal and the ratio, and
• the disturbance observer generates an angular speed signal by subtracting the angular speed detection signal from a product of a reciprocal of the set inertia and an integral of a difference between the shaft torque detection signal and the higher-level command torque signal, and generates the disturbance compensation torque signal by multiplying the angular speed signal by a product of the set inertia and a predetermined gain.