Variable-speed irrigation system

An irrigation system comprising:

• a center pivot structure;
• a main section assembly coupled to the center pivot structure, the main section assembly including a plurality of interconnected spans;
• a plurality of tower structures for supporting the interconnected spans, each one of the plurality of tower structures including a variable-speed drive unit for selectively driving a tower structure at a selected speed;
• a plurality of sensors, each one of the plurality of sensors associated with a corresponding one of the plurality of interconnected spans and configured to determine an alignment of a corresponding one of the plurality of interconnected spans;
• a plurality of variable-drive control units, each variable-drive control unit of the plurality of drive control units in communication with a corresponding variable-speed drive unit and a corresponding sensor, each variable-drive control unit configured to control the selected speed of the corresponding variable-speed drive unit to maintain the plurality of interconnected spans in a substantially linear orientation with respect to adjacent ones of the plurality of interconnected spans along a generally longitudinally oriented axis,
• wherein the selected speed of the corresponding variable-drive control unit is based upon the alignment.

An irrigation system comprising:

• a center pivot structure;
• a main section assembly coupled to the center pivot structure, the main section assembly including a plurality of interconnected spans;
• a plurality of tower structures for supporting the interconnected spans, each one of the plurality of tower structures including a switched reluctance motor for selectively driving a tower structure at a selected speed;
• a plurality of sensors, each one of the plurality of sensors associated with a corresponding one of the plurality of interconnected spans and configured to determine an alignment of a corresponding one of the plurality of interconnected spans;
• a plurality of variable-drive control units, each variable-drive control unit of the plurality of drive control units in communication with a corresponding variable-speed drive unit and a corresponding sensor, each variable-drive control unit configured to control the selected speed of the corresponding switched reluctance motor to maintain the plurality of interconnected spans in a substantially linear orientation with respect to adjacent ones of the plurality of interconnected spans along a generally longitudinally oriented axis,
• wherein the selected speed of the corresponding variable-drive control unit is based upon the alignment.