A compressor control apparatus includes a rectifier configured to rectify AC power to DC power; an inverter including a plurality of switching elements, configured to convert the DC power into a three-phase voltage according to a pulse width modulation (PWM) signal applied to the plurality of switching elements; a motor configured to receive a three-phase current based on the three-phase voltage; a current detector configured to detect a sum of a first phase current, a second phase current, and a third phase current supplied to the motor; and a controller configured to differently determine a duty ratio of the PWM signal applied to each of the plurality of switching elements, and to determine the first phase current, the second phase current, and the third phase current, respectively, based on the determined duty ratio and the sum of the currents detected from the current detector.

A compressor control apparatus includes a rectifier configured to rectify AC power to DC power; an inverter including a plurality of switching elements, configured to convert the DC power into a three-phase voltage according to a pulse width modulation (PWM) signal applied to the plurality of switching elements; a motor configured to receive a three-phase current based on the three-phase voltage; a current detector configured to detect a sum of a first phase current, a second phase current, and a third phase current supplied to the motor; and a controller configured to differently determine a duty ratio of the PWM signal applied to each of the plurality of switching elements, and to determine the first phase current, the second phase current, and the third phase current, respectively, based on the determined duty ratio and the sum of the currents detected from the current detector.

A power conversion system includes a power conversion apparatus and a programming support apparatus connected to the power conversion apparatus. The power conversion apparatus includes power conversion circuitry, program storage that stores a control program configured to control the power conversion circuitry, and a control unit that controls the power conversion circuitry according to a control program. The programming support apparatus includes a display data generation unit that generates display data of a block diagram illustrating a content of the control program using a plurality of functional blocks, and a link indicating input and output of information between the functional blocks based on the control program stored in the program storage.

A power conversion system includes a power conversion apparatus and a programming support apparatus connected to the power conversion apparatus. The power conversion apparatus includes power conversion circuitry, program storage that stores a control program configured to control the power conversion circuitry, and a control unit that controls the power conversion circuitry according to a control program. The programming support apparatus includes a display data generation unit that generates display data of a block diagram illustrating a content of the control program using a plurality of functional blocks, and a link indicating input and output of information between the functional blocks based on the control program stored in the program storage.

A device includes an input converter, an output converter, and a controller. The input converter is electrically coupled to an electrical meter and an energy production array. The output converter is electrically coupled to the energy production array and a load. The controller is communicatively coupled to the input converter, the output converter, the energy production array, and the load. The input converter and the output converter are positioned between the electrical meter and the load.

A system includes an electronic power converter and a controller. The electronic power converter supplies power to one or more motor drives of an HVAC system. The controller obtains a plurality of pulse width modulation (PWM) algorithms. Each PWM algorithm has an associated spectrum of frequencies. The controller further determines one or more resonance frequencies associated with the HVAC system. The controller also selects a first PWM algorithm from the plurality of PWM algorithms wherein the spectrum of frequencies of the first PWM algorithm lacks frequency peaks that overlap with the one or more resonance frequencies associated with the HVAC system. The controller further operates the electronic power converter according to the first PWM algorithm.

A direct power conversion device includes a control unit. tb=1/|fdc−n×fL|. fdc is a frequency twice as high as a frequency of an AC power supply, fL is a frequency of periodic load fluctuations, and n is a positive integer that maximizes tb. In a half period of power supply during a period of tb, the half period including a timing at which peaks of a fundamental wave of load torque and an absolute value of a power supply voltage substantially coincide with each other, the control unit being configured to control the switching elements so that two or more local maximum points appear in the half period of power supply, in a waveform obtained by combining a second harmonic, a fourth harmonic, and a sixth harmonic of a power supply frequency contained in a waveform of an absolute value of a motor current vector.

An Uninterruptible Power Supply (UPS) including an input configured to receive input AC power, a backup power input configured to receive backup DC power having a first voltage level from a backup power source, a converter configured to convert the input AC power from the input and the backup DC power from the backup power input into DC power having a second voltage level, the converter including an input selection circuit configured to selectively couple the converter to the input and the backup power input, an inductor, a first converter switch configured to couple a first end of the inductor to a neutral connection, and a second converter switch configured to couple a second end of the inductor to the backup power input via the input selection circuit.

The invention comprises an apparatus, comprising an inductor, the inductor comprising: an inductor core; a first winding section comprising a first cast shape and a second winding section comprising the first cast shape, the first winding section mechanically joined to the second winding section to form a winding, the winding forming a wound shape about the inductor core. Optionally and preferably, a third winding section, comprising a second cast shape, mechanically joins the first winding section to the second winding section and a mechanical connector and/or an aluminum weld join the first winding section to the third winding section.

A method for operating a multi-level bridge power converter includes providing a plurality of switching devices of the power converter in one of a neutral point clamped topology or an active neutral point clamped topology. The method also includes providing a plurality of deadtimes for the switching devices. Further, the method includes selecting one of the deadtimes for each of the switching devices such that at least two of the switching devices operate according to different deadtimes. Moreover, the method includes operating the switching devices at the selected deadtimes to allow a first group of the switching devices to switch slower than a second group of the switching devices such that the first group of the switching devices satisfy safe operating requirements while the second group of the switching devices switch faster than the first group.