摘要:
Disclosed is an electric motor system with reduced torque ripple comprising a sinusoidally magnetized permanent magnet, a sinusoidal inverter, a higher resolution position sensor, a composite iron stator yoke, a composite reinforced plastic rotor core and shaft; and a high gear ratio gear reduction box. The novel combination of magnet, inverter, sensor, plastic rotor core and shaft and high gear ratio gear box substantially reduces the torque ripple on the shaft of said motor system.
摘要:
A method and an apparatus using the method that generates an index pulse which includes firstly the generation of a first electronic signal which includes a first level and a second level based upon a multiphase sinusoidal motor control circuit. Secondly, the generation of at least a second electronic signal that includes a first level and a second level based upon a multiphase sinusoidal motor control circuit wherein the first electronic signal and the second electronic signal are levelly spaced apart based upon the phase number of the multiphase sinusoidal motor control circuit wherein a set difference in level exists for a first specified period between the first and said the signal. Thirdly, the determination of the index pulse based upon a transition from the first level to the second level of the first electronic signal.
摘要:
A method and apparatus for controlling the torque of and reducing torque ripple in a permanent magnet motor without using current sensors. By eliminating the need for current sensors, low frequency torque ripple is reduced. A voltage mode control method is implemented to control the motor. In response to the position and speed of the rotor and a torque command signal, a controller develops motor voltage command signals indicative of the voltage required to produce the desired motor torque. A rotor position encoder determines the angular positions of the rotor. From the angular positions of the rotor, a speed measuring circuit determines the speed of the rotor. The position and speed signals are applied to the controller. The controller uses this information and develops the motor voltage command signals indicative of the voltage needed to produce the desired motor torque. An inverter is coupled between a power source and the controller. The circuit applies phase voltages to the motor, in response to the motor voltage command signals, to produce the desired motor torque.
摘要:
An apparatus and method are described for adjusting the modeled resistance used in the control of an electric motor drive to match the actual resistance of the motor. The system comprises sensors for measuring motor current and motor speed, which data is inputted into a processing unit. The processor uses the measured rotational speed to calculate what the proper current should be based upon the torque desired. If the calculated current is not equal to the measured current, then the modeled resistance of the motor is altered to correct the current. The invention is particularly useful for permanent magnet brushless motors operating in voltage mode.
摘要:
A method of interfacing an electromagnetic sensor with a controller in a motor control system, the method including: applying an excitation signal to the electromagnetic sensor; receiving a first electromagnetic sensor output signal based on the excitation signal, the first electromagnetic sensor signal comprising an amplitude modulated signal corresponding to a position of a rotor of the electromagnetic sensor; and receiving a second electromagnetic sensor output signal based on the excitation signal, the second electromagnetic sensor signal comprising another amplitude modulated signal corresponding to the position of the rotor of the electromagnetic sensor. The method also includes sampling the first electromagnetic sensor signal and the second electromagnetic sensor signal at about an instance synchronous with the excitation signal to demodulate the first electromagnetic sensor signal and the second electromagnetic sensor signal and decoding a resultant of the sampling to identify the position of a rotor of the electromagnetic sensor.
摘要:
An apparatus measures relative displacement between a first end and a second end of a shaft. The first and second ends being centered on a shaft axis. The apparatus includes first and second ferromagnetic plates. The first ferromagnetic plate has a first side and a second side and is connected to the first end. The first ferromagnetic plate is centered on the shaft axis and has a plurality of ferromagnetic teeth extending from the first side and in a first direction parallel to the shaft. The second ferromagnetic plate has a first side and a second side and is connected to the second end. The second ferromagnetic plate is centered on the shaft axis. The first and second ferromagnetic plates form a gap. The apparatus further includes a plurality of magnets having a magnetic field and a sensing device. The magnets are coupled to the first side of the second ferromagnetic plate. The sensing device is disposed within the gap for sensing a magnetic flux of the magnetic field.
摘要:
A passively clamped quasi-resonant DC link ("PCQRL") converter includes an output inverter having a plurality of switches, and a DC link between a DC power source and the output inverter. The DC link is realized by a clamp transformer having a clamp factor not higher than 1.1-1.3 and a small auxiliary inductance which is switched by a pair of auxiliary switches (driven by the same gating signal) and a pair of diodes. When the auxiliary switches are turned "ON", the DC link voltage drops to zero; and the switches of the output inverter then can be switched under zero voltage condition with no switching losses. Most of the modulation schemes, including PWM, are applicable to the DC link design.
摘要:
A method of interfacing an electromagnetic sensor with a controller in a motor control system, the method including: applying an excitation signal to the electromagnetic sensor; receiving a first electromagnetic sensor output signal based on the excitation signal, the first electromagnetic sensor signal comprising an amplitude modulated signal corresponding to a position of a rotor of the electromagnetic sensor; and receiving a second electromagnetic sensor output signal based on the excitation signal, the second electromagnetic sensor signal comprising another amplitude modulated signal corresponding to the position of the rotor of the electromagnetic sensor. The method also includes sampling the first electromagnetic sensor signal and the second electromagnetic sensor signal at about an instance synchronous with the excitation signal to demodulate the first electromagnetic sensor signal and the second electromagnetic sensor signal and decoding a resultant of the sampling to identify the position of a rotor of the electromagnetic sensor.
摘要:
A dual stage drive for a switched reluctance motor (SRM) is disclosed, the SRM having a plurality of phase coils associated therewith. In an exemplary embodiment, the dual stage drive includes at least one of the plurality of phase coils coupled to a first power bus, and at least another one of the plurality of phase coils coupled to a second power bus. Energy within the at least one phase coil coupled to said first power bus is dissipated through said second power bus.
摘要:
A dual voltage motor drive is disclosed. In an exemplary embodiment, the motor includes a rotor assembly, rotatingly disposed within a stator assembly, and a plurality of motor phase windings configured to be energized in a determined sequence to cause a rotation of the rotor assembly. The plurality of motor phase windings are divided into a first group of windings selectively energized by a first voltage source, and a second group of windings selectively energized by a second voltage source, wherein the motor remains operational in the event of a failure of one of the first and second voltage sources.