The multi-stage crop termination system includes a main frame assembly connected to first and second roller frames. Accordingly, the vehicle dynamic controller may be activated very quickly after ignition, while a less costly relative steering wheel angle sensor may be employed. The hairpin-line resonator includes a first hairpin-line low pass filter, and a second hairpin-line LPF connected in parallel to the first hairpin-line LPF reversely. The submerged arc furnace reactive compensation device includes a control cabinet and a capacitance automatic compensation cabinet.