Abstract: A charging and discharging device includes a transformer consisting of a primary winding and multiple secondary windings including at least a first secondary winding and a second secondary winding; multiple ports electrically connected to the primary winding and the multiple secondary windings of the transformer, respectively, wherein the multiple ports at least include a first port electrically connected to the primary winding via a first conversion circuit; a second port electrically connected to the first secondary winding via a second conversion circuit; and a third port electrically connected to the second secondary winding via a third conversion circuit; and a first controllable switch connected between the first conversion circuit and the primary winding.

Abstract: A method for transferring power between medium voltage feeders via a direct current link in a power distribution network includes setting an iteration step value for each of a set of power reference quantities of the link, setting an initial value of each reference quantity, iteratively changing values of each reference quantity, and selecting one changed value of the set by: changing a present value of each reference quantity with the set iteration step value into a new value, measuring a total active power at a substation of the power distribution network for each new value, and selecting the new value that provides the lowest measured total active power at the substation. A next iteration is performed with the selected new value as present value for the one of the set of power reference quantities and with the present value for the other of the set of power reference quantities.

Abstract: A master-slave communication system for a single-phase to multi-phase AC power supply includes a master and a plurality of slaves that are connected in parallel and configured to supply single-phase to multi-phase AC power. The master includes a main communication control board and at least one phase communication control board. The main communication control board is in communication with the phase communication control board. The slaves each include at least one phase communication control board. The master and an adjacent one of the slaves as well as every adjacent two of the slaves are in communication with each other through a network transmission cable connected between the network connection ports of the same phase, thereby improving the communication transmission speed and reliability between the master and the slaves and further improving the output quality of the AC power supply.

Abstract: A control device (101) for controlling a power converter (109) is configured to form a frequency droop value based on electric power supplied by the power converter to an alternating current system, decrease a frequency control value by the frequency droop value, form a power control value based on a target value of the electric power, increase the frequency control value by the power control value, and supply the frequency control value to the power converter to control alternating voltage frequency of the power converter. The electric power is driven to a value at which a combined effect of the frequency droop value and the power control value makes the alternating voltage frequency of the power converter to be the same as operating frequency of the alternating current system. Thus, the electric power can be controlled by changing the power control value.

Abstract: A master-slave communication system for a single-phase to multi-phase AC power supply includes a master and a plurality of slaves that are connected in parallel and configured to supply single-phase to multi-phase AC power. The master and the slaves each include a main communication control board and at least one phase communication control board. The main communication control board is in communication with the corresponding phase communication control board. The master and an adjacent one of the slaves as well as every adjacent two of the slaves are in communication with each other through a network transmission cable connected between the main communication control boards, thereby improving the communication transmission speed and reliability between the master and the slaves and further improving the output quality of the AC power supply.

Abstract: A method of measuring an AC input voltage at an input of a power converter includes measuring a DC bus voltage corresponding to the power converter. During a positive half-cycle of the AC input voltage, the method includes measuring a first voltage at the input of the power converter. During a negative half-cycle of the AC input voltage, the method includes turning on a high-side switch, measuring a second voltage at the input of the power converter, and computing a third voltage equal to the second voltage minus the DC bus voltage. The method further includes providing the AC input voltage as the first voltage during the positive AC half-cycle and the third voltage during the negative AC half-cycle.

Abstract: The invention discloses a module energy store converter system (10) comprising the following: at least one converter arm (12) comprising a plurality of standard modules (14) connected in series, and at least one extra-low voltage module (ELV module) (40), wherein the standard modules (14) and the ELV module can be connected such that inputs (48) of a transducer (46) of the ELV module can be optionally connected to the storage element (26) of an adjacent standard module (14) serially and/or anti-serially, or the transducer (46) can be decoupled from the storage element (26), and/or the inputs (48) of the transducer (46) can be optionally connected to the storage element of an adjacent standard module (14) in parallel, or the transducer (46) can be decoupled from the storage element (26).

Abstract: An energy storage MMC topology is proposed to avoid the microcirculation of battery. The topology consists of six bridge arms in three stages and can be connected to DC system and AC system. Each bridge arm is composed of one bridge arm inductance and N energy storage sub-modules with the same structure in series. The energy storage sub-modules include a half-bridge power module, a battery energy storage module and a group of anti-parallel thyristors. The group of anti-parallel thyristors is connected in series over the DC cable between the battery energy storage module and a capacitor of the half-bridge power module. The switching control is performed on the battery in the energy storage MMC according to the systematic operating mode.

Abstract: Disclosed is a reactance-injecting module and its method of use to balance the currents among the phases of polyphase electric power transmission lines or to manage power flow among alternate paths, where the reactance-injecting module has high-speed, dedicated communication links to enable the immediate removal or reduction of injected reactance from all phases of a phase balancing cluster when a fault is detected on any one of the multiple phases. The reactance-injecting module may communicate information on a detected fault to the other reactance-injecting modules of the phase balancing cluster within 10 microseconds after the fault is detected to allow the phase balancing cluster to eliminate injected reactance from all phases within a time that is short compared to a cycle of the alternating current, such as 1 millisecond after the fault is detected. This provides extremely fast neutralization of injected reactance to minimize interference with fault localization analyses.

Abstract: A switching control circuit for controlling a power supply circuit that generates an output voltage from an alternating current (AC) voltage inputted thereto. The power supply circuit includes an inductor receiving a rectified voltage corresponding to the AC voltage, and a transistor controlling an inductor current flowing through the inductor. The switching control circuit controls switching of the transistor, and includes a first arithmetic circuit that calculates a first time period, from when the transistor is turned off to when the inductor current reaches a predetermined value, based on a first voltage corresponding to the rectified voltage, a second voltage corresponding to the output voltage, and the inductor current upon turning on of the transistor; and a drive circuit that causes the transistor to be on in a second time period corresponding to the second voltage, and causes the transistor to be off in the first time period.

Abstract: A control method for a power factor correction circuit is disclosed. The power factor correction circuit includes a first bridge arm, a second bridge arm, an output capacitor and an active clamp unit. The control method includes steps of providing a first driving waveform to control a main switch, providing a second driving waveform to control an auxiliary switch, and providing a third driving signal to control a fifth switch. A first delay time is between the turning-off time point of the third driving signal and the turning-on time point of the first driving waveform, a second delay time is between the turning-on time point of the first driving waveform and the turning-off time point of the second driving waveform, and a third delay time is between the turning-off time point of the second driving waveform and the turning-on time point of the third driving signal.

Abstract: The present disclosure relates to a power management system for a motor vehicle, the motor vehicle including at least one energy storage device and at least one solar cell for generating electrical energy, the system being provided with a charging device which is designed to both charge the energy storage device with electrical energy from an external energy source and to supply an external consumer with electrical energy from the energy storage device and/or from the solar cell, the charging device including a DC-DC converter, an inverter and a rectifier.

Abstract: A pulse width modulation (PWM) interleaving system is provided. The PWM interleaving system includes active harmonic filters (AHFs). The AHFs are disposed in parallel with each other and with a load. The AHFs are electrically coupled to a common coupling point that is electrically interposed between a grid and the load. The AHFs are configured to affect, by PWM, a characteristic of current flowing between the grid and the load. The PWM interleaving system further includes a controller operably coupled to the AHFs and configured to synchronize the PWMs of the AHFs to thereby cancel ripple currents propagating towards the grid.

Abstract: A power control circuit includes a converter, a signal generation circuit, and control circuitry. The converter includes a switching circuit. The converter transforms an output voltage from a power generator. The signal generation circuit operates the switching circuit of the converter. The control circuitry changes an operation of the switching circuit.

Abstract: A controller performs a first control for controlling the power source power factor or a power source harmonic of the harmonic current such that an input power factor of at least one of a plurality of connection devices changes in a direction preceding the power source power factor in a case where the power source power factor changes in a lagging direction, and performs a second control for controlling the power source power factor or the power source harmonic such that the input power factor of at least one of the connection devices changes in a direction lagging behind the power source power factor in a case where the power source power factor changes in a leading direction.

Abstract: A power transmission system can include a transformer and compensator circuit(s), each coupled between a node of the transformer and a ground connection. The compensator circuit(s) can each be configured to counteract a DC signal component of an AC signal at the transformer. The compensator circuit(s) can include a converter circuit having an AC side and a DC side and configured to convert a DC voltage on the DC side to an AC signal at the AC side. The compensator circuit(s) can include a DC link coupled to the DC side of the converter circuit. The compensator circuit(s) can include a controller configured to measure a DC signal component between the load and the ground; to determine, based at least in part on the DC signal component, a compensating signal configured to counteract the DC signal component; and to inject, by the converter circuit, the compensating signal to counteract the DC signal component.

Abstract: Disclosed are a control method and system for a parallel converter system, including a common AC voltage controller and a separate current controller for each converter; the AC voltage controller generates an active current, a wattless current, and a system voltage phase reference value and, by means of communication, sends same to the current controller of each converter in island control mode to be a converter control signal; the active and wattless current outputted by each converter, along with the corresponding current reference value, accomplish the objective of the parallel converter system collectively controlling the amplitude and frequency of an AC bus voltage. The method and system are highly reliable and effectively ensure the synchronization of a plurality of converters.

Abstract: Transients occur on power transmission lines for unpredictable reasons including breakers opening and closing, load variations, and inputs to the grid from renewable energy sources turning on and off. A recursive technique allows a linear function to be fitted to a non-linear grid dynamic of the power line transients. The technique is adaptive and helps to stabilize an impedance injection unit while it injects correcting impedance into a transmission line for the purpose of achieving power flow control. When applied to many injection units the technique may also help to stabilize the overall grid. The stabilization system using the recursive technique provides real-time monitoring of the associated power line and stabilization with respect to power line transients.

Abstract: A method of operating a multilevel converter having multiple phase modules, each with three phase module branches. In a first switching position, a switching device of each phase module connects an alternating voltage connection of the phase module to a first connection point between a first phase module branch and a third phase module branch. In a second switching position, the switching device connects the alternating voltage connection to a second connection point between the third phase module branch and a second phase module branch. In the method, circulating currents of the multilevel converter are controlled in accordance with total energy variables and differential energy variables of the phase modules to balance the energy between the phase module branches.

Abstract: A system and method using thyristors to protect a series-connected Flexible AC Transmission Systems (FACTS) device from surge currents are disclosed. According to some embodiments, the system includes a thyristor connected in shunt with the FACTS device to be protected. The system further includes control circuitry coupled to the thyristor to drive a gate of the thyristor with a direct current (DC) signal and turn on the thyristor in a time span on order of microseconds. The system and method can be used to protect any series-connected FACTS device that is in danger of being exposed to surge current such as a reclose after a deadline.

Abstract: Systems, methods, and devices relating to operating a power generation facility to contribute to the stability of the power transmission system. A controller operates on the power generation facility to modulate real power or reactive power or both in a decoupled manner to contribute to the stability of the power transmission system. Real power produced by the power generation facility can be increased or decreased between zero and the maximum real power available from the PV solar panels, as required by the power system. Reactive power from the power generation facility can be exchanged (injected or absorbed) and both increased or decreased as required by the power transmission system. For solar farms, the solar panels can be connected or disconnected, or operated at non-optimal power production to add or subtract real or reactive power to the power transmission system.

Abstract: The present invention provides a series compensator and a control method. The series compensator includes a series transformer, a series transformer bypass device, a voltage source converter, a high-speed converter bypass device, a high-speed switch, and a reactor. The reactor and the high-speed switch are connected in parallel to form a current limiting module; one winding of the series transformer has two ends connected in series to a line, and the other winding thereof is sequentially connected to the current limiting module and the high-speed converter bypass device; the voltage source converter and the high-speed converter bypass device are connected in parallel; and at least one winding of the series transformer are connected in parallel to at least one series transformer bypass device.

Abstract: One or more embodiments are directed to a multiport power delivery architecture that reduces the cost and maximize the power utilization. According to some aspects, embodiments solve problems associated with charging a battery with multiple adapter. Some embodiments enable supplying system load and charging a battery from two or more adapters simultaneously through a single sensing resistor.

Abstract: The present invention is directed toward a switching power supply and improvements thereof. In accordance with an embodiment, a switching power supply is provided. The switching power supply comprises: a first power supply stage that forms an intermediate regulated voltage; and a second power supply stage configured to accept the intermediate regulated voltage and configured to form a regulated output voltage, wherein the intermediate voltage is set to an initial target level upon start-up of the power supply and wherein the intermediate regulated voltage is set to a second target level during steady-state operation of the power supply.

Abstract: A voltage compensation device according to an embodiment includes a controller including first and second coordinate transformation circuits, and first and second arithmetic parts. The first coordinate transformation circuit generates first and second outputs that are mutually-orthogonal by performing a rotating coordinate transformation of the normal-phase components of a three phase AC. The first arithmetic part calculates a system voltage based on a DC component of the first output and generates a first compensation amount corresponding to a compensation voltage set to compensate a shift of the system voltage from a preset target voltage. The second coordinate transformation circuit generates third and fourth outputs that are mutually-orthogonal by performing a rotating coordinate transformation of reverse-phase components of the three-phase AC.

Abstract: According to one embodiment, a battery control device includes a charge and discharge circuit and a processor. The processor determines, based on an information regarding a secondary battery electrically connected to the charge and discharge circuit, whether or not a diagnosis implementation condition is satisfied; controls the charge and discharge circuit to charge the secondary battery only after discharging or charging up to a charging-start SOC if the diagnosis implementation condition is satisfied; acquires measurement data of a voltage and a current of the secondary battery while charging; estimates an internal state parameter of the secondary battery based on the measurement data; and diagnoses a deterioration state of the secondary battery based on the internal state parameter of the secondary battery.

Abstract: Non-fault disturbance-based method and system for measuring short-circuit capacity of a power grid on site including: connecting or disconnecting a reactive compensation device to or from a power grid point of common coupling, to generate a disturbance on a power grid; obtaining total active power and total reactive power of a load of the point of common coupling before the disturbance; determining a vector difference between a voltage of the power grid point of common coupling before the disturbance and a voltage of the power grid point of common coupling after the disturbance; obtaining a voltage effective value of the power grid point of common coupling before the disturbance; obtaining a capacity of the reactive compensation device; and determining a short-circuit capacity of the point of common coupling according to total active power, total reactive power, vector difference between voltages, voltage effective value, and capacity of the reactive compensation device.

Abstract: A radio-frequency switch is disclosed, comprising a set of field-effect transistors disposed between a first node and a second node. In some embodiments, each field-effect transistor of the set of field-effect transistors has a respective source, drain, gate, and body. In some embodiments, the radio-frequency switch includes a compensation circuit coupled in parallel with the set of field-effect transistors, the compensation circuit configured to compensate a non-linearity effect generated by the set of field-effect transistors.

Abstract: Variable delay time in power converters. At least some example embodiments are methods of operating a power converter, the methods comprising: inducing, by a converter controller, a positive voltage and a positive current on a secondary winding of a transformer of a power converter, the inducing by a bridge circuit coupled to a primary winding of the transformer; creating, by the converter controller, a first ramp signal proportional to the positive current; sensing a first inductor current through a first inductor, the first inductor coupled between the secondary winding and a load, and the sensing creates a signal indicative of the first inductor current; and changing conductive state of a first freewheeling switch from conductive to non-conductive when a magnitude of the first ramp signal crosses a magnitude of the signal indicative of the first inductor current.

Abstract: In prior art grid systems, power-line control is done by substation based large systems that use high-voltage (HV) circuits to get injectable impedance waveforms that can create oscillations on the HV power lines. Intelligent impedance injection modules (IIMs) are currently being proposed for interactive power line control and line balancing. These IIMs distributed over the high-voltage lines or installed on mobile platforms and connected to the HV power lines locally generate and inject waveforms in an intelligent fashion to provide interactive response capability to commands from utility for power line control.

Abstract: A case for a pair of earbuds including a housing having first and second cavities formed within the housing, the first cavity configured to receive a first earbud in the pair of earbuds and the second cavity configured to receive a second earbud in the pair of earbuds; a lid attached to the housing; a first pair of electrodes positioned within the housing adjacent to the first cavity; a second pair of electrodes positioned within the housing adjacent to the second cavity; and charging circuitry coupled to the first and second pairs of electrodes, the charging circuitry including a high frequency inverter configured to receive a DC power signal and output a high frequency AC signal to each of the first and second pairs of electrodes.

Abstract: Provided is a power supply circuit in which a first end of a first inductor is connected to a path linking a first input terminal to a first connection point, a second end of the first inductor is connected to a first end of a bypass capacitor, a first end of a second inductor is connected to a path linking the first input terminal to a second connection point, a second end of the second inductor is connected to a first end of the bypass capacitor, a second end of the bypass capacitor is connected to a second output terminal, a first reactor and the first inductor are magnetically coupled to each other, a second reactor and the second inductor are magnetically coupled to each other, and a control circuit performs switching control over a first switching element and a second switching element, using an interleaving method.

Abstract: Circuits and methods for electronically adjusting an effective inductance of one or more primary inductors in a circuit. The circuit may include a plurality of sub-circuits connected in parallel between an input and an output of the circuit. Each sub-circuit may include a primary inductor and an auxiliary inductor inductively coupled to the primary inductor. The circuit may further include first circuitry coupled to the primary inductor, wherein the first circuitry configured to introduce an oscillating first voltage across the primary inductor; and second circuitry coupled to the auxiliary inductor, wherein the second circuitry is configured to introduce an oscillating second voltage across the auxiliary inductor. The amplitudes of the second voltages may be selected to reduce a difference between effective inductances of the primary inductors.

Abstract: An electronic apparatus and an electronic system may include a first power delivery network (PDN) and a second PDN. The first PDN may include a first inductor as a segment of a power rail of the first PDN, while the second PDN may include a second inductor as a segment of a power rail of the second PDN. The first inductor and the second inductor may form a magnetically coupled inductor. The magnetically coupled inductor may provide migrated impedance ZT to the first PDN induced by the magnetically coupled inductor. The migrated impedance ZT to the first PDN may help the first PDN to reduce its voltage noise. Other embodiments may be described and/or claimed.

Abstract: A converter station includes two line-commutated converters for energy transmission through a bipolar high voltage direct current transmission link. The two converters are electrically connected in an anti-parallel circuit to the same pole of the high-voltage direct current transmission link. One of the converters is operated as a rectifier in an AC grid and the other converter is operated as an inverter in the AC grid. A station reactive power exchanged by the converter station with the AC grid is controlled by real power stipulations for converter real powers which are exchanged between the converters and the AC grid. A method for operating the converter station is also provided.

Abstract: A method for minimizing DC capacitance of a cascade multilevel converter is provided. On the basis of balancing of capacitor voltages, the method estimates instantaneous value of the DC side capacitor voltages in a circuit through an energy conservation law, and uses a proportional resonance controller to control a grid-connected current to realize adjustment of the grid-connected current without static difference, such that the cascade multilevel converter can operate in a small capacitance mode, the system volume is greatly reduced, the system cost is reduced, the control is easy to be implemented, and the capacitor voltage is free from overshoot and the system has a better rapidity.

Abstract: A static transfer switch is provided for supplying power to a load alternately from two different power sources. Switching between the two power sources may occur within a fraction of one electrical cycle. In response to sensing degraded performance in the power source supplying the load, a gate signal is turned off to a first switch coupled between the power source and the load. A third switch coupled between an energy storage and the first switch is also closed to release a current to the input or output of the first switch The current forces a drop in current conducted through the first switch and causes the first switch to open and stop conducting current. A second switch coupled between the alternate power source and the load is then closed to supply power to the load from the alternate power source.

Abstract: Systems and methods for reducing a likelihood that an engine exceeds its torque or power limit at a specific speed are provided. Also provided are systems and methods for reducing a likelihood that DC-DC converters and AC inverters overload a generator at a specific speed.

Abstract: A system and method for preventing voltage collapse of a wind turbine power system includes receiving a power input value and a voltage input value from a point of common coupling of the wind turbine power system. The method also includes determining a limit cycle reference point of the wind turbine power system as a function of the input values. The method further includes comparing the limit cycle reference point to at least one predetermined threshold. If the limit cycle reference point is greater than the at least one predetermined threshold, the method includes determining a delta value for the real and reactive voltage commands of the wind turbine power system. Further, the method includes determining updated real and reactive voltage commands based on the delta value. As such, the method also includes operating the wind turbine power system based on the updated real and reactive voltage commands.

Abstract: An active line filter (ALF) with multiple outputs includes a first output providing a first output power form having a first output current, the first output power form being coupled to a first winding on an inductive element; and a second output providing a second output power form having a second output current, the second output power form being coupled to a second winding on the inductive element. An input receives an input power form having an input current and an input voltage. A pulse-width modulator (PWM) provides a PWM output signal controlling timing of switching of a transistor to control application of the input voltage of the input power form to the first winding of the inductive element. An error amplifier receives a signal indicative of the first output voltage and generating an error amplifier output signal.

Abstract: A control system and methods for a multilevel power converter are provided. The converter includes a rectifier coupled to a DC link having a midpoint coupled to electrical ground that divides the DC link into two halves. The control system is configured to generate a reference current command for controlling an output of the rectifier, the reference current command generated based on a difference between a desired and measured DC link voltage value. The system is also configured to determine a zero-sequence current component of input current supplied to the multilevel power converter, wherein the zero-sequence current component is associated with non-linearities in said multilevel power converter that cause ground current injection into the input current by the rectifier. The system is further configured to subtract the determined zero-sequence current component from the reference current command to reduce the ground current injected into the input current by the rectifier.

Abstract: A vehicle power system includes an electric machine, an inverter electrically connected with the electric machine, and a controller. The controller, while injecting AC voltage output by the inverter into the electric machine as a DC voltage input to the inverter changes, drives a duty ratio of the inverter toward a constant value to obtain resolver offset information associated with the electric machine from a current response of the electric machine to the AC voltage.

Abstract: A power converter apparatus includes a plurality of inverters where each inverter receives power from a separate DC voltage source. The apparatus includes a magnetic structure. The magnetic structure includes a primary winding for each inverter, where each primary winding is connected to an output a corresponding inverter and each primary winding is coupled to a magnetic core, and a single secondary winding coupled to one or more magnetic cores to which each primary winding is coupled. The apparatus includes a rectifier that receives an AC waveform from the secondary winding and that rectifies the AC waveform and is connected to a load at output terminals. The secondary winding includes a secondary bus and the one or more magnetic cores of the magnetic structure that are arranged to provide a pathway for the secondary winding that minimizes a length of the secondary winding.

Abstract: A method for controlling a power supply includes: acquiring working state information of the power supply in a current operation; determining whether a state value of the power supply in the current operation satisfies a preset condition according to the working state information; setting a first control strategy for controlling the current operation of the power supply as a second control strategy when the preset condition is satisfied; storing the state value in the current operation and the first control strategy of the power supply in the current operation when the preset condition is not satisfied, and modifying the first control strategy to obtain the second control strategy according to an adjustment strategy; and loading the second control strategy from the machine-learning control circuitry in next operation, and controlling the next operation of the power supply according to the second control strategy.

Abstract: A maximum power point tracking controller includes an input port for electrically coupling to an electric power source, an output port for electrically coupling to a load, a control switching device, and a control subsystem. The control switching device is adapted to repeatedly switch between its conductive and non-conductive states to transfer power from the input port to the output port. The control subsystem is adapted to control switching of the control switching device to regulate a voltage across the input port, based at least in part on a signal representing current flowing out of the output port, to maximize a signal representing power out of the output port.

Abstract: A containerized power flow control system is described, for attachment to a power transmission line or substation. The system includes at least one container that is transportable by road, rail, sea or air. A plurality of identical impedance injection modules is operable while mounted in the container, wherein each of the modules is configurable to inject a pre-determined power control waveform into the power line.

Abstract: A power factor correction (PFC) system includes a desired OFF period module that determines a desired OFF period for a switch of a PFC circuit based on an input voltage to the PFC circuit and an output voltage of the PFC circuit. A switching control module transitions the switch from an ON state to an OFF state when a measured current through an inductor of the PFC circuit is greater than a demanded current through the inductor and maintains the switch in the OFF state for the desired OFF period after the transition from the ON state to the OFF state.

Abstract: An AC/DC converter and conversion method are provided, in which an AC input is rectified and shaped by a waveform shaping capacitor. A current source circuit is used to provide the output current to the output load which has a parallel bulk capacitor. The current source circuit is switched on and off with timing which is dependent on the phase of the AC input signal. This enables a relatively high power factor, for example between 0.7 and 0.9, with low cost circuitry with few components.

Abstract: A method of operating a multilevel power converter includes using, through a processing device, a model of an electrical circuit that includes a plurality of switching devices, a plurality of flying capacitors, and an AC terminal. The method also includes regulating a voltage level of the AC terminal through selecting, at least partially based on the model, a possible charging state of the electrical circuit. Each possible switching state has a voltage level that at least partially corresponds to a commanded voltage level for the AC terminal. The method further includes selecting, at least partially based on the model of the electrical circuit and at least partially based on the selected possible switching state, a charging state from a plurality of possible charging states. The method also includes setting the switching state of the electrical circuit at least partially based on the selected charging state of the electrical circuit.

Abstract: A power conversion device includes three inverters configured to convert DC power of DC buses into single-phase AC power, and a controller configured to control the three inverters so as to generate three-phase AC power. The controller is configured to generate a fundamental wave command for generating one-phase AC power constituting the three-phase AC power, and to generate an adjustment wave command having triple the frequency of the fundamental wave command. Additionally, the controller is configured to output a phase voltage command, in which the adjustment wave command is superimposed on the fundamental wave command, and to determine an initial phase of the adjustment wave command to be offset from an initial phase of the fundamental wave command so as to reduce a voltage ripple occurring in the DC buses at double the frequency of the fundamental wave command.