Motor assembly for driving a pump or rotary device with a low inductance resistor for a matrix converter

A plate assembly configured for use with an electric motor assembly for driving a pump, the plate assembly comprising:

• a hub with a central opening extending from an end wall of the plate assembly and configured to receive an output shaft of the electric motor assembly therethrough, the plate assembly coupleable about the output shaft and having a cavity that houses motor drive electronics;
• and
• a resistor within the cavity, the resistor comprising:
• an input connector,
• an output connector, and
• a pair of conductor elements extending from the input and output connectors and extending adjacent each other along a curved serpentine path so the resistor has a generally circular outer perimeter and a generally circular inner perimeter,
• wherein the curved serpentine path of the pair of conductor elements allows current to flow through the pair of conductor elements so that magnetic fields generated by the current flow through the pair of conductor elements cancel each other, thereby providing the resistor with low inductance.

An electric motor assembly for driving a pump, comprising:

• an electric motor having an output shaft that extends along a central axis of the electric motor, the electric motor being operable to rotate the output shaft;
• a motor frame that houses the electric motor so that the output shaft protrudes from an end of the motor frame;
• a first plate having a hub with a central opening configured to receive the output shaft therethrough, the first plate coupleable about the output shaft and having a cavity configured to house motor drive electronics;
• and
• a resistor assembly within the cavity, the resistor assembly comprising:
• a case having a generally annular shape and defining a recess, and
• a resistor within the case comprising an input connector, an output connector, and a pair of conductor elements extending from the input and output connectors and extending adjacent each other along a curved serpentine path so the resistor has a generally circular outer perimeter and a generally circular inner perimeter,
• wherein the curved serpentine path of the pair of conductor elements allows current to flow through the pair of conductor elements so that magnetic fields generated by the current flow through the pair of conductor elements cancel each other, thereby providing the resistor with low inductance.