Michihiro Yamashita

Basic study of anti-slip control without speed sensor for multiple motor drive of electric railway vehicles

Vector control methods without speed sensor for electric vehicles are under discussion. We propose a new method of slip detection without a speed sensor by focusing on the current of each motor. The proposed method makes it easier to detect small slips. Furthermore, the adhesion force is presumed in order to determine the current recovery value based on the behavior of motor current when a slip occurs. Thus the detection of small slip can be compatible with the hold of high motor current. We performed simulation to verify the effectiveness of the proposed readhesion control method that uses the presumed adhesion force.

A novel anti-slip control without speed sensor for electric railway vehicles

Recently, vector control methods without a speed sensor for electric vehicles are under discussion. The authors propose a new method of slip detection without a speed sensor by focusing on the current of each motor. The proposed method makes it easier to detect small slips. Furthermore, the adhesion force is presumed in order to determine the current recovery value based on the behavior of motor current when a slip occurs. Thus the detection of small slip can be compatible with the hold of high motor current. We performed simulation to verify the effectiveness of the proposed readhesion control method that uses the presumed adhesion force.

A novel slip control method considering axle-weight transfer for electric locomotive

When a wheel slip occurs on a certain axle or when re-adhesion control is executed, the tractive force of the wheel-slip axle changes, which causes pitching of the bogie and the carbody. As a result, a change occurs in the weight acting on other axles in adhesion status, and wheel slips are likely to be induced. We developed a control system designed to reduce the induction of wheel slips considering axle-weight changes caused by other wheel slips. To verify the effectiveness of the control method, we conducted a water spring wheel-slip test using an EH200-type DC electric locomotive.

Development of a new traction control method to suppress wheel-slip of electric locomotives

When a wheel slip occurs on a certain axle or when re-adhesion control is executed, the tractive effort of the wheel-slip axle changes, which causes pitching of the bogie and the carbody. As a result, weight on other axles changes, which may induce wheel slip. This paper explains the development of a control system designed to reduce wheel slip induced by axle-weight changes caused by other wheel slips. To verify the effectiveness of the control method, a water spray wheel-slip test was conducted using an EH200-type DC electric locomotive.

A traction control method for slip suppression of electric locomotives driven by parallel-connected dual induction motors controlled by one inverter

The multiple main motor drive system for railway vehicles is more excellent than another circuit system of one inverter and one induction motor, from the viewpoint of cost and space-saving of electric equipment. On the other hand, the motors fed by one inverter are controlled collectively. As a result, when re-adhesion control is executed, the traction force and vehicle acceleration of the former system may be low in comparison with those of the latter system, the individual main motor drive system. This paper explains the development of a traction control method designed so as to increase the tractive effort of a multiple traction motor drive locomotive (main circuit systems consisting of parallel-connected induction motors). To verify the effectiveness of the control method, simulation tests and experiments were performed.

Anti-slip re-adhesion control method for increasing the tractive force of locomotives through the early detection of wheel slip convergence

We have developed a re-adhesion control method for increasing tractive force through early detection of wheel slip convergence, using less delayed rotational acceleration signal than the conventional one for slip detection. We focus on the effect of the restraint of tangential force change by the early slip convergence detection. Accordingly, the slip induction of other axes is restrained and increase of tractive force of locomotives is expected. Its effectiveness has been verified by simulation tests and running tests using a HD300-Type diesel hybrid shunting locomotive.