Development of an Electro-Hydraulic Controlled Rig-Type CVT and Its Performance Test for Optimal Operation

An electronic-hydraulic controlled rig type CVT(Continuously Variable Transmission) system was developed and its performance tests were carried out for the optimal operation. As a control algorithm, torque control strategy was suggested considering the engine simulator characteristics. Also, a real time control and operation program called CVTCON consisting of (1)CVT test rig operation, (2) system test, (3)system control and (4)data management modules was developed for the electronic-hydraulic CVT system. By using the CVTCON and the CVT test rig, performance tests were carried out for the optimal operation in case of (1) constant throttle and (2) acceleration driving modes. Experimental results showed that the electronic-hydraulic CVT system and the control software developed in this study made the engine simulator run following the optimal operating line closely, which was set arbitrarily representing the best fuel economy or the maximum power mode.