Single phase to three phase dynamoelectric converter

A single phase to three-phase dynamoelectric converter for starting and running a plurality of three-phase motors or like three-phase operating loads from a single-phase power supply, said converter comprising:

• (a) a three-phase electric motor/generator comprising first, second and third Y-wound stator windings adapted to have said first and second windings connected to a suitable source of single-phase power;
• (b) run capacitor means connected between said first powered stator winding and said third unpowered stator winding to develop a voltage in said third winding at a phase angle different from the phase angles in said first and second powered windings;
• (c) a potential-type relay comprising a set of normally closed contacts and a winding to open them, said winding connected between said second and third stator windings;
• (d) a slave relay comprising a set of normally open contacts and a winding to close them, said slave relay winding connected between said first stator winding and said potential relay winding through said set of normally closed potential relay contacts;
• and,
• (e) start capacitor means, connected between said third, unpowered stator winding and one of said slave relay open contacts, adapted to provide immediate capacitor-phase shifted starting power to said third stator winding when said slave relay contacts close upon said slave relay winding becoming energized by the initial voltage increase developed between said second and third stator windings when external single-phase power is applied thereto, and wherein said slave relay contacts are adapted to open and disconnect said starting capacitor means when the voltage developed between said second and third stator windings reach a level sufficient to energize said potential relay windings to open said relay contacts, to allow said motor/generator to run under balanced power and produce balanced three-phase power to be drawn from all three stator windings for use in driving external three-phase motors.