摘要:
A method of detecting a phase winding fault in a multi-phase electric machine is executable via a motor controller, and includes measuring feedback signals of the machine, including each phase current, and generating reference phase voltages for each phase. The method includes calculating a predetermined voltage value using the feedback signals and reference phase voltages, and comparing the voltage value to a corresponding threshold to determine the fault. A control action is executed when the voltage value exceeds the corresponding threshold. The voltage value is one or more of: a ratio of a normalized negative sequence voltage to a modulation index, an RMS voltage for each phase, and total harmonic distortion of each phase current. An apparatus detects the fault, and includes a motor controller and an algorithm as set forth above. The apparatus may include a voltage inverter for generating a multi-phase alternating current output for powering the machine.
摘要:
Systems and methods are disclosed to provide torque linearity in the field-weakening region for an electric (e.g., IPM) machine. The systems and methods implement a field weakening and a torque linearity control loop for linearizing torque generated by an electric machine. As a result, torque linearity is maintained when the electric machine operates in the field weakening region.
摘要:
A method for controlling an alternating current (AC) motor includes choosing a pulse sequence based on a ripple current in the AC motor at a sampling instant; and providing a voltage to the AC motor based on the pulse sequence.
摘要:
According to an example embodiment, a method is provided for limiting an operational temperature of a motor. The method includes generating a maximum allowable current I*S(max) for a motor based on a temperature difference between a temperature reference T* of a power inverter module and a semiconductor device temperature T of the power inverter module. The method further includes generating a maximum allowable torque T*e(max) based on the maximum allowable current I*S(max) and a maximum allowable flux Ψ*S(max), and using the maximum allowable torque T*e(max) to limit the torque command T*e in order to suppress the semiconductor device temperature T to below the temperature reference T*.
摘要:
A method of using a cycloconverter switches a first switch of the first topology type to an on state after a magnitude of a current through an output inductor becomes less than a predetermined current threshold, and switches a second switch of the first topology type to an off state a first time after switching the first switch to the on state. The cycloconverter includes nodes on a first port, nodes on a second port, a switch pair coupled between a first node of the first port and a first node of the second port, a switch pair coupled between a second node of the first port and a first node of the second port, a switch pair coupled between a first node of the first port and a second node of the second port, and a switch pair coupled between a second node of the first port and a second node of the second port. Each switch pair includes a switch of each topology type.
摘要:
A control architecture for an electrical inverter includes a synchronous frame current regulator and a stationary frame current regulator. The stationary frame current regulator receives input currents that represent filtered versions of stationary frame currents that correspond to the inverter output currents. The control architecture employs an adaptive filter module that filters the stationary frame currents to remove the fundamental motor frequency component (and its related harmonics), thus extracting any low frequency harmonic components. The stationary frame current regulator processes the low frequency components, while the synchronous frame current regulator processes the fundamental frequency component, resulting in suppression of low frequency oscillations in the inverter output.
摘要:
A method for controlling an alternating current (AC) motor includes choosing a pulse sequence based on a ripple current in the AC motor at a sampling instant; and providing a voltage to the AC motor based on the pulse sequence.
摘要:
Methods and apparatus are provided for an electric vehicle embodying an axial flux traction motor directly coupled to a wheel thereof. The traction motor comprises a stator having coils for producing a magnetic field, an annular rotor magnetically coupled to the stator and mechanically to an output shaft. Permanent magnets of alternating polarity are mounted on the annular rotor. Magnetic shunts bridge a portion of the stator slots above the coils. The magnets are arranged in groups with group-to-group spacing exceeding magnet-to-magnet spacing. Adjacent edges of the magnets diverge. The method comprises, looking up d- and q-axis currents to provide the requested torque and motor speed for the available DC voltage, combining at least one of the d- and q-axis currents with a field weakening correction term, converting the result from synchronous to stationary frame and operating an inverter therewith to provide current to the coils of the motor.
摘要:
PWM methods and apparatus are provided for loss minimized control of AC motors taking into consideration inverter non-linear limitations. The method comprises providing a voltage to the AC motor based on a switching cycle, adding a duty cycle of a zero vector to each phase leg of the switching cycle when a duty cycle of a first phase leg of the switching cycle is less than a minimum duty cycle, and subtracting the duty cycle of the zero vector from each phase leg of the switching cycle when a second duty cycle of a second phase leg is greater than a maximum duty cycle. The minimum duty cycle and maximum duty cycle indicate distortion regions.
摘要:
A method for decoupling a harmonic signal from an input signal wherein the harmonic signal is harmonic relative to a signal other than the input signal. An angular position of the other signal is multiplied by a value representing the harmonic to obtain an angular position multiple. A harmonic decoupling block uses the angular position multiple to obtain correction signals representing the harmonic signal, and subtracts the correction signals from the input current to decouple the harmonic signal from the input signal. This method is useful for decoupling unwanted harmonics from currents into which high-frequency signals have been injected for control of electric motors.