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US 2022/0103110 A1Published application
Power conversion device and electric power steering device
AssigneeMitsubishi Electric Corporation
InventorsTatsuya MORI, Akira FURUKAWA, Kenta KUBO
Life of this patent
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Abstract
A power conversion device is configured to acquire, from a current detector at a timing A, a first phase current detection value in a first phase being a phase corresponding to a phase voltage command to be compared to a first carrier wave signal, calculate a first phase current calculation value corresponding to the first phase based on an acquisition result, acquire, from the current detector at a timing B, a second phase current detection value in a second phase being a phase corresponding to a phase voltage command to be compared to a second carrier wave signal, and to calculate a second phase current calculation value corresponding to the second phase based on an acquisition result.
Claims20
A power conversion device, comprising:
- an inverter which includes a high electric potential-side switching element and a low electric potential-side switching element which are provided in correspondence with each phase of three phases, and is configured to invert a DC voltage output from a DC power supply to AC voltages by switching on/off the high electric potential-side switching elements and the low electric potential-side switching elements, and to output the AC voltages;
- a current detector which is connected in series to the respective low electric potential-side switching elements of the inverter, and is configured to detect respective values of phase currents in the three phases as phase current detection values;
- and
- a controller configured to calculate phase voltage commands in the three phases, and to control the inverter in accordance with the calculated phase voltage commands in the three phases,
- wherein the controller is configured to:
- compare the phase voltage command in at least one phase of the phase voltage commands in the three phases and a first carrier wave signal to each other, and compare the phase voltage command in a remaining phase of the phase voltage commands in the three phases and a second carrier wave signal different from the first carrier wave signal in phase by ½ cycle of a carrier wave cycle of the first carrier wave signal to each other, to thereby control the high electric potential-side switching elements and the low electric potential-side switching elements of the inverter to switch on and off;
- acquire, from the current detector at a timing A, a first phase current detection value as the phase current detection value in a first phase being a phase corresponding to the phase voltage command to be compared to the first carrier wave signal, and calculate a first phase current calculation value corresponding to the first phase based on the first phase current detection value acquired at the timing A;
- and
- acquire, from the current detector at a timing B, a second phase current detection value as the phase current detection value in a second phase being a phase corresponding to the phase voltage command to be compared to the second carrier wave signal, and calculate a second phase current calculation value corresponding to the second phase based on the second phase current detection value acquired at the timing B.
6 more elements
A power conversion device, comprising:
- an inverter which includes a high electric potential-side switching element and a low electric potential-side switching element which are provided in correspondence with each phase of three phases, and is configured to invert a DC voltage output from by a DC power supply to AC voltages by switching on/off the high electric potential-side switching elements and the low electric potential-side switching elements, and to output the AC voltages;
- a current detector configured to detect, as a bus current detection value, a value of a bus current input from the DC power supply to the inverter;
- and
- a controller configured to calculate phase voltage commands in the three phases, and to control the inverter in accordance with the calculated phase voltage commands in the three phases,
- wherein the phase voltage commands in the three phases are set as a maximum phase voltage command, a medium phase voltage command, and a minimum phase voltage command in descending order of a magnitude of value,
- wherein the controller is configured to:
- apply a first voltage shift method of equally shifting the respective phase voltage commands in the three phases such that the maximum phase voltage command matches a maximum value of a first carrier wave signal or a second voltage shift method of equally shifting the respective phase voltage commands in the three phases such that the minimum phase voltage command matches a minimum value of the first carrier wave signal;
- compare the phase voltage command in at least one phase of the shifted phase voltage commands in the three phases and the first carrier wave signal to each other, and compare the phase voltage command in a remaining phase of the shifted phase voltage commands in the three phases and a second carrier wave signal different from the first carrier wave signal in phase by ½ cycle of a carrier wave cycle of the first carrier wave signal to each other, to thereby control the high electric potential-side switching elements and the low electric potential-side switching elements of the inverter to switch on and off;
- and
- acquire the bus current detection value from the current detector at each of a timing A and a timing B, and calculate, based on the bus current detection values acquired at the timing A and the timing B, a first phase current calculation value corresponding to a first phase being a phase corresponding to the phase voltage command to be compared to the first carrier wave signal and a second phase current calculation value corresponding to a second phase being a phase corresponding to the phase voltage command to be compared to the second carrier wave signal, and
- wherein the timing A and the timing B are timings different from each other, and are timings at which the bus current is flowing from the DC power supply to the inverter.
8 more elements
Dependencies are inferred from the claim text.