Electromagnetic vibration suppression device and electromagnetic vibration suppression program

An electromagnetic vibration suppression device for suppressing vibration of a running steel plate, comprising:

• a plurality of electromagnet pairs arranged in a width direction of the steel plate, each electromagnet pair including a combination of electromagnet oppositely arranged to each other in a thickness direction of the steel plate running in predetermined direction;
• and
• a control unit configured to control electric currents fed to the respective electromagnets, the control unit suppressing vibration of the steel plate running between the electromagnets of the respective electromagnet pairs, wherein
• a plurality of sensor pairs, each sensor pair detecting presence of the steel plate between the electromagnet pair, and each sensor arranged on each of electromagnets to face the steel plate excluding the electromagnet arranged in the width direction center position or near, and each sensor pair arranged to an opposing location interpose the steel plate between two sensors in pair, and
• the control unit includes pseudo displacement amount calculation means, pseudo edge position calculation means, and current amount control means,
• the pseudo displacement calculation means calculating a pseudo displacement amount α′ of the steel plate, wherein the value α′ is calculated as a difference between a provisional meandering width and a value of ½ W, in which W is a width dimension of the steel plate, wherein the provisional meandering width is a distance from a steel plate center position, which is a width direction center position of the steel plate in a regular state in which the steel plate does not meander in the width direction, to a switched sensor reference position based on at least one of a position of a sensor closest to the width direction center portion of the electromagnet pair region among sensors switched from an ON state in which presence of the steel plate is detected between the electromagnets of the electromagnet pairs to an OFF state in which the presence of the steel plate is not detected between the electromagnets of the electromagnet pairs and a position of a sensor most distant from the width direction center portion of the electromagnet pair region among sensors switched from the OFF state to the ON state,
• the pseudo edge position calculation means calculating a pseudo edge position of the steel plate by using a formula of ½ W±α′, wherein the pseudo edge position is an approximative position of an actual edge position of the steel plate, and
• the current amount control means individually controlling amounts of electric currents fed to the electromagnets on the basis of the pseudo edge position of the steel plate calculated by the pseudo edge position calculation means,
• among said plurality of electromagnet pairs, the current amount control means detects an edge-position detecting electromagnet pair in which the pseudo edge position is disposed therebetween, the pseudo edge position obtained by the formula above in the pseudo edge position calculation means, and then, a driving condition is made on the electromagnets making up the electromagnet pairs located at a side closer to a widthwise center than the edge-position detecting electromagnet pair, while a non-driving condition is made on other electromagnets located at a side closer to the widthwise end than the edge-position detecting electromagnet pair.