An AC-rotating-electric-machine control apparatus includes two or more electric-power conversion circuits that control respective voltages to be applied to the two or more groups of multi-phase armature windings, for each of the two or more groups of multi-phase armature windings; each of the two or more electric-power conversion circuits has two or more switching devices for opening or closing the corresponding group of multi-phase armature windings, for each of the phases; the two or more switching devices are switching-controlled in such a way that opening operation or duty control can be applied to the corresponding group of multi-phase armature windings.

Examples include a method for controlling a variable speed drive driving an electric motor. The variable speed drive is connected to an electric power source and comprises a passive DC-link and an inverter stage controlled by a first controller of the variable speed drive. The passive DC-link is connected to the inverter stage. The method comprises running the electric motor to reach a steady-state operating point, measuring a plurality of values of current or voltage of the passive DC-link, and computing, by a second controller, a frequency spectrum of the DC-link based on the plurality of values of current or voltage measured. The method further comprises detecting a specific resonance frequency by comparing amplitudes of the frequency spectrum to a predetermined pattern, and modifying filter parameters of a digital filter of the DC-link or control parameters of a control law of the electric motor based on the specific resonance frequency.

A motor drive system includes a direct current (DC) bus that provides a DC link voltage across a DC link capacitor, and a split DC link mid-point circuit connected in parallel with the DC link capacitor. The split DC link mid-point circuit establishes a mid-point reference based on the DC link voltage. A power inverter is in signal communication with the DC bus. The power inverter includes one or more gate driver units configured to drive one or more corresponding switches. Each gate driver unit includes a mid-point ground connection that is connected to the mid-point reference. The split DC link mid-point circuit can define a voltage divide that establishes the mid-point reference and can be used to monitor the DC link voltage.

A device for driving a plurality of motors, including an inverter connected to a DC terminal; a multi-phase motor connected to the inverter; and a single-phase motor serially connected to the multi-phase motor, wherein a number of frequency of current input to the multi-phase motor when driving the single-phase motor and the multi-phase motor at the same speed is smaller than the number of frequency of current input to the multi-phase motor when driving the single-phase motor and the multi-phase motor at different speeds. Accordingly, a plurality of motors can be simultaneously driven at different speeds, by using a single inverter.

Provided is a method for controlling a wind turbine, in particular an electric generator of said wind turbine. The method includes an optimization during which a suitable operating parameter for controlling said wind turbine or generator thereof is determined, in particular in an iterative manner. The optimization includes providing a multidimensional space comprising a plurality of parameters; providing an objective function for said multidimensional space, e.g., a simplex has a shape of a triangle or a tetrahedron; and determining one parameter of said multidimensional space as a suitable operating parameter by applying said objective function to said multidimensional space, in particular in an iterative manner. The method includes selecting a suitable operating parameter as an operating parameter for said wind turbine or generator thereof; and operating said wind turbine or generator based on said operating parameter, in particular by controlling a converter connected to said generator.

Methods and systems for operating a driveline disconnect clutch actuator are provided. In one example, the driveline disconnect clutch actuator may be supplied with electric power to activate and deactivate a driveline disconnect clutch when electric power is available via a first power source. The driveline disconnect clutch actuator may be supplied with electric power to open the driveline disconnect clutch when output from the first driveline disconnect clutch is unavailable.

A method for stabilizing a DC link voltage of an electrical converter, the method including: determining a DC link voltage signal for the DC link voltage of the electrical converter; determining a fluctuation signal of the DC link voltage by applying a high pass filter to the DC link voltage signal; determining a torque offset by multiplying the fluctuation signal with a gain value; and modifying a reference torque with the torque offset for controlling the electrical converter. The gain value is adjusted by: determining a DC link voltage ripple from the DC link voltage signal; and comparing the DC link voltage ripple with a threshold and, when the DC link voltage ripple is higher than the threshold, increasing the gain value.

A power management system comprises an AC-power-source controller configured to control power supply between the AC power source and a common DC bus, the AC-power-source controller further configured to limit AC power supplied from the AC power source to the common DC bus to a first AC-power-source power limit; a power inverter configured to invert the DC power on the common DC bus into AC output power for driving the electric motor; a DC power source configured to supply DC power to the common DC bus; and a DC-power-source controller configured to control power supply between the DC power source and the common DC bus, the DC-power-source controller further configured to start supplying DC power from the DC power source to the common DC bus in response to a detection of a voltage drop on the common DC bus from a AC-power-source reference voltage to a DC-power-source reference voltage.

A power converter includes a first substrate on which a module including a switching element is mounted, a second substrate on which a smoothing capacitor is mounted, and a terminal block connecting the first substrate and the second substrate, with the first and second substrates located to face each other. The terminal block includes a current path over which at least one of current flowing from the module to the smoothing capacitor and current flowing from the smoothing capacitor to the module flows.

A three-phase regenerative drive configured for operation from a single phase alternating current (AC) power source, the three-phase regenerative drive including a three-phase converter having inputs for connection to a single-phase AC source, the three-phase converter having three phase legs, a three-phase inverter for connection to a motor, the three phase inverter configured to provide three phase command signals to the motor, and a DC bus connected between the three-phase converter and the three-phase inverter. A first phase leg of the three-phase converter and a second phase leg of the three-phase converter are employed to direct current from the single-phase AC source to the DC Bus and a third phase leg of the three phase legs of the three-phase converter returns current to a return of the AC source.