Motors & Drives Information

Chorus Motors plc (CHOMF) announces that a patent, titled "PWM Motor Drive Apparatus with Increase of Low Speed Capabilities" No. 6,614,202, was issued by the US Patent Office on September 2nd 2003.

The patent refers to an inverter/drive combination that provides increased overload capacity at low speeds. In particular, the inverter can be supplied with a range of harmonic waveforms to increase the output capabilities of the inverter.

The extra voltage this represents can be used in different ways. It can be used to increase the speed of the rotor shaft. By winding the motor with an additional number of series turns, the motor can translate the additional voltage into extra torque at low speeds. Alternatively, by synthesizing the inverter voltage waveform, increased current output can be obtained when the drive forms part of a generator system.

Instead of getting more power or speed or current - depending on the chosen arrangement - the extra voltage can be traded for cost savings by using a smaller inverter for the same job as would normally require a larger conventional inverter. Drive costs, and especially the cost of power electronics in the inverter, can be reduced by 60% for traction and start-stop motor applications without any loss in performance over motors of comparable size. Any application requiring high start-up torque without compromising high speed operation, such as materials handling, locomotives, and starter-alternators, benefits from this technology.

"With Chorus(R) Meshcon, electric motor technology is making the next leap forward," said Stuart Harbron, Chorus Motor plc's Chief Patent Officer. "Modern techniques allow us to configure electrical power to suit the specific needs of today's industrial, automotive, and aerospace applications. Chorus Meshcon is the ideal partner for forward-looking designers seeking to break out of the straitjacket of traditional motor design and make full use of the power that has always been available -- and to do it all with much healthier profit margins."

# posted by Medical Information : 5:05 AM