Power conversion device
AssigneeToshiba Mitsubishi-Electric Industrial Systems Corporation
InventorsRyota OKUYAMA, Taichiro TSUCHIYA
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Abstract
In the present power conversion device, when a fault occurs in a power system (1) and DC voltage (VDC) of a capacitor (15) included in a unit converter (5) exceeds a protection level (VH), the operation of an inverter (10) is stopped. When the DC voltage (VDC) decreases to a recovery level (V1) or lower, DC voltage control of the inverter (10) is resumed to quickly decrease the DC voltage (VDC). When the DC voltage (VDC) decreases to a recovery level (V2) or lower, reactive power control of the inverter (10) is resumed. Thus, even when a fault occurs in the power system (1), the operation of the inverter (10) can be quickly resumed.
Claims8
A power conversion device comprising:
- a capacitor;
- an inverter configured to transfer electric power between the capacitor and a power system;
- a first controller configured to perform DC voltage control of the inverter such that DC voltage of the capacitor attains a first command value;
- and
- a second controller configured to perform reactive power control of the inverter such that reactive power transferred between the capacitor and the power system attains a second command value, wherein
- the first and second controllers are configured to stop the DC voltage control and the reactive power control, respectively, in response to the DC voltage exceeding a protection level higher than the first command value,
- the first controller is configured to resume the DC voltage control in response to the DC voltage decreasing to a first recovery level or lower, the first recovery level being equal to or lower than the protection level, and
- the second controller is configured to resume the reactive power control in response to the DC voltage decreasing to a second recovery level or lower, the second recovery level being lower than the first recovery level.
Dependencies are inferred from the claim text.