A chassis dynamometer system for a vehicle with a left-front wheel, a right-front wheel, a left-rear wheel, and a right-rear wheel, the chassis dynamometer system comprising:
- a left-front driven member, right-front driven member, left-rear driven member and right-rear driven member on which the left-front wheel, right-front wheel, left-rear wheel and right-rear wheel are respectively placed, and are driven by rotation of each;
- a left-front dynamometer, right-front dynamometer, left-rear dynamometer and right-rear dynamometer are respectively coupled to the left-front driven member, the right-front driven member, the right-rear driven member and the right-rear driven member;
- a left-front speed sensor which detects a left-front speed of the left-front dynamometer;
- a right-front speed sensor which detects a right-front speed of the right-front dynamometer;
- a left-rear speed sensor which detects a left-rear speed of the left-rear dynamometer;
- a right-rear speed sensor which detects a right-rear speed of the right-rear dynamometer;
- and
- a control device configured to generate left-front torque current command for the left-front dynamometer, right-front torque current command for the right-front dynamometer, left-rear torque current command for the left-rear dynamometer, and right-rear torque current command for the right-rear dynamometer based on the left-front, right-front, left-rear, and right-rear speed sensors, wherein the control device includes:
- a front-side uniform-speed synchronization controller configured to generate a front-side synchronization correction input for the left-front dynamometer and the right-front dynamometer so that a speed difference between the left-front speed and the right-front speed is eliminated;
- a rear-side uniform-speed synchronization controller configured to generate a rear-side synchronization correction input for the left-rear dynamometer and the right-rear dynamometer so that a speed difference between the left-rear speed and the right-rear speed is eliminated;
- a left-front drive force estimator configured to estimate a left-front drive force transferred from the left-front wheel to the left-front driven member;
- a right-front drive force estimator configured to estimate a right-front drive force transferred from the right-front wheel to the right-front driven member;
- a left-rear drive force estimator configured to estimates a left-rear drive force transferred from the left-rear wheel to the left-rear driven member;
- a right-rear drive force estimator configured to estimate a right-rear drive force transferred from the right-rear wheel to the right-rear driven member;
- a front-side load balance processor configured to generate a first left-front load balance correction input for the left-front dynamometer and a first right-front load balance correction input for the right-front dynamometer, based on the left-front drive force and the right-front drive force;
- a rear-side load balance processor configured to generate a first left-rear load balance correction input for the left-rear dynamometer and a first right-rear load balance correction input for the right-rear dynamometer, based on the left-rear drive force and the right-rear drive force;
- a left-front torque current command generator configured to generate and input to the left-front dynamometer a left-front torque current command based on the first left-front load balance correction input and the front-side synchronization correction input;
- a right-front torque current command generator configured to generate and input to the right-front dynamometer a right-front torque current command based on the first right-front load balance correction input and the front-side synchronization correction input;
- a left-rear torque current command generator configured to generate and input to the left-rear dynamometer a left-rear torque current command based on the first left-rear load balance correction input and the rear-side synchronization correction input;
- and
- a right-rear torque current command generator configured to generate and inputs to the right-rear dynamometer a right-rear torque current command based on the first right-rear load balance correction input and the rear-side synchronization correction input,
- wherein the front-side load balance processor independently varies the first left-front load balance correction input and the first right-front load balance correction input, and raises the first left-front load balance correction input as the right-front drive force increases, and raises the first right-front load balance correction input as the left-front drive force increases, and
- wherein the rear-side load balance processor independently varies the first left-rear load balance correction input and the first right-rear load balance correction input, and raises the first left-rear load balance correction input as the right-rear drive force increases, and raises the first right-rear load balance correction input as the left-rear drive force increases.