Fault Tolerant, Sensorless Linear Switched Reluctance Motor
Researchers at U.T. Dallas have developed a low cost, fault tolerant, sensorless Linear Switched Reluctance Motor. Linear motors convert electrical energy directly into piston-like linear motion. Oil, Gas, and geothermal applications could greatly benefit from this type of machine. The motor designed in the REVT laboratory of the University of Texas at Dallas has the potential to be a very low cost motor, operate without vulnerable sensors, and continue to operate with damage that would be catastrophic to conventional motor designs.
In applications such as oil wells, natural gas wells, and geothermal, linear motion and down-hole pumping can be advantageous. Rotational motors are not well suited for down-hole pumping due to their bulkiness and rotational motion. Linear motors are becoming an attractive technology to meet this demand. Linear motors are built with narrow diameters compared to rotational motors and can be cascaded to provide additional power.
Technology This motor has three key advantages over traditional linear motors. The first is the absence of permanent magnets. Permanent magnets are expensive and can become demagnetized (rendering the motor useless) in high temperatures. This allows this new motor to be put in more harsh conditions that traditional motors can not withstand. The second advantage is the motor's ability to run without sensors. Conventional motors have vulnerable and expensive sensors or encoders. The new motor design does not need sensors or encoders. This directly increases reliability and lifetime of the machine. The third advantage of our motor is it's ability to run at reduced performance when faults do occur. If a motor winding becomes damaged for any reason, we can continue to accurately control the motor with the remaining windings.
Patent Pending with the University of Texas at Dallas.