A motor control system includes a DC-to-DC converter including a semiconductor switch and a reactor that cooperates with the switch to convert input-side DC bus voltage across first and second input-side DC buses into predetermined output-side DC bus voltage across first and second output-side DC buses and to output the output-side voltage, control circuitry that controls duty factor of the switch and determine, based on input-side detection value of the input-side voltage and output-side detection value of the output-side voltage, whether there is failure in the system when the factor is 100 percent and reactor-current detection value of reactor current through the reactor is approximately zero, a smoothing capacitor connected to the output-side buses and disposed between the output-side buses, and an inverter that is connected to the capacitor through the output-side buses, converts DC power from the output-side buses into AC power and supplies the power to a motor.

A drive system for a BLDC motor having poles implemented by separate coils that are activated in corresponding phases, which comprises a controller for controlling the level and phase of input voltages supplied to the separate coils; a controlled inverter with outputs, for applying phase-separated input voltages to each of the separate coils at desired timing for each input voltage, determined by the controller; a power source for feeding power to the controlled inverter; an up/down DC-DC converter for converting the feeding power to the input voltages according to a command signal provided by the controller. The controller is adapted to sample the instantaneous angle of the rotor of the BLDC motor; sample the input voltage input voltage and the current of each phase to obtain the input power P; and for each input voltage, calculate the phase difference value that corresponds to the input power and feeds the phase difference value to the up/down DC-DC converter, thereby causing the up/down DC-DC converter to apply each input voltage to its corresponding coil at a specific timing for obtaining an optimal match between each input voltage and the current that is being built up in the corresponding coil.

A vehicle electrical system includes an electrical storage, a first multiphase electrical machine having a plurality of stator windings connected to common neutral point, a first inverter operatively connected to the electrical storage and to the first multiphase electrical machine, wherein the first inverter has a plurality of switch legs with switches, a second multiphase electrical machine having a plurality of stator windings connected to a common neutral point, a second inverter operatively connected to the electrical storage and to the second multiphase electrical machine, wherein the second inverter has a plurality of switch legs with switches, a bidirectional buck-boost DC/DC converter operatively connected to the common neutral point of the first multiphase electrical machine and to the common neutral point of the second multiphase electrical machine and configured for using at least one stator winding of each of the first and second multiphase electrical machines as buck-boost inductance.

According to the integrated power conversion apparatus and method according to the exemplary embodiment of the present disclosure, the on-board battery charger (OBC), the lower voltage battery charger (LDC), and the traction converter (TC) are integrated to convert the power so that all the functions which need to be performed by the power conversion system of the related art can be performed. Further, the number of switches is reduced to increase a power density and not only the number of switches, but also the number of controllers is reduced to improve feasibility.

The power conversion apparatus includes a converter circuit that converts an alternating-current voltage output from an alternating-current power supply into a direct-current voltage. The converter circuit includes unit converters. The power conversion apparatus includes current detectors that detect respective currents flowing through respective reactors. In first and second unit converters adjacent to each other among the unit converters, a phase difference between a first phase and a second phase is changed from a reference phase difference when a total current of currents detected by the respective current detectors is greater than a threshold. The first phase is a phase at a time when the switching element of the first unit converter is turned on. The second phase is a phase at a time when the switching element of the second unit converter is turned on.

A power converter for converting a voltage of direct-current power output from a direct-current power supply, the power converter including: a printed circuit board; a reactor being configured with a conductor pattern of the printed circuit board; a semiconductor element that is connected to another end of the reactor and performs switching for storing electrical energy in the reactor so as to boost the voltage of the direct-current power from a first voltage to a second voltage; a capacitor that smooths the direct-current power boosted to the second voltage; a diode that is connected to the another end of the reactor and supplies the direct-current power boosted to the second voltage to the capacitor; and a cooler, wherein the reactor, the semiconductor element, and the diode are included in a module in a single package, and the module is cooled by the cooler.

A motor system of the present disclosure includes a permanent magnet motor including a stator having N-phase windings and a rotor having a permanent magnet, N being a natural number greater than or equal to three, an inverter that supplies N-phase drive currents for generating a rotating magnetic field to the stator, and a zero-phase current supply unit that supplies a zero-phase current to the N-phase windings of the stator. The motor system applies the zero-phase current to the N-phase windings in response to an inter-terminal voltage of the permanent magnet motor reaching a predetermined value of the inter-terminal voltage.

A motor driving apparatus includes: a power storage device; a motor; a first inverter; a second inverter; an external AC terminal; a third inverter including a DC terminal and an AC terminal; a transformer connected to the AC terminal of the third inverter; a first switch capable of switching the AC terminal of the first inverter to a state of being connected to either the first winding connection portion or the external AC terminal; a second switch capable of switching the AC terminal of the second inverter to a state of being connected to either the second winding connection portion or the transformer; and a third switch capable of switching the power storage device to a state of being connected to either the DC terminal of the first inverter and the DC terminal of the second inverter or the DC terminal of the third inverter.

Provided is a work machine capable of improving workability. The work machine is provided with: a motor 14; a first power supply unit 180 connected to a battery pack 5 and supplying a boosted power to the motor 14; and a second power supply unit 130 connected to an external AC power supply and supplying a boosted power to the motor 14. The voltage and current of the first power supply unit 180 and the voltage and current of the second power supply unit 130 can be variably controlled by a control circuit 182 and a control circuit 136, respectively. The control circuits 136, 182 perform control so that the power output from the respective first power supply unit 180 and the second power supply unit 130 is combined and supplied to the motor 14.

A control device of a multi-phase converter having N converter circuits connected in parallel includes: a determination unit configured to determine each share ratio of the N converter circuits to unevenly share input current to the multi-phase converter among the N converter circuits such that a conversion efficiency indicating a ratio of output power from the multi-phase converter with respect to input power to the multi-phase converter is higher in the case where the input current is unevenly shared by the N converter circuits compared to the case where the input current is evenly shared by the N converter circuits when the number of driven converter circuits is one or more and N−1 or less and the start condition is satisfied; and a diagnosis unit configured to diagnose an abnormality of the N converter circuits when the N converter circuits are driven in accordance with the determined share ratios.