Power conversion system and control device for same
AssigneeMitsubishi Electric Corporation
InventorsTakeshi Kikuchi, Fuminori Nakamura, Ryosuke Uda
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Abstract
A power conversion system includes: a self-commutated converter connected between an AC power system, and a first DC main line and a DC return line; a line-commutated converter connected between the AC power system, and the DC return line and a second DC main line; and a control device. When activating the self-commutated converter and the line-commutated converter, the control device activates the self-commutated converter, and after completion of activation of the self-commutated converter, activates the self-commutated converter. The self-commutated converter can be activated first to take advantage of a function of the self-commutated converter that is not included in the separately-commutated converter.
Claims14
A power conversion system comprising:
- a first self-commutated converter connected between
- a first AC power system, and
- a first DC main line and a DC return line for first high voltage DC transmission;
- a first line-commutated converter connected between
- the first AC power system, and
- the DC return line and a second DC main line for second high voltage DC transmission;
- a second self-commutated converter connected between
- a second AC power system, and
- the first DC main line and the DC return line;
- a second line-commutated converter connected between
- the second AC power system, and
- the DC return line and the second DC main line;
- and
- a control device, wherein
- when activating the first self-commutated converter and the first line-commutated converter in a case where the first AC power system is in a power failure state and the second AC power system is in a non-power failure state, the control device activates the first self-commutated converter based on a DC voltage supplied from the second self-commutated converter through the first DC main line and the DC return line, and after completion of activation of the first self-commutated converter, activates the first line-commutated converter.
A power conversion system comprising:
- a first self-commutated converter connected between
- a first AC power system, and
- a first DC main line and a DC return line for first high voltage DC transmission;
- a first line-commutated converter connected between
- the first AC power system, and
- the DC return line and a second DC main line for second high voltage DC transmission;
- and
- a control device, wherein
- when activating the first self-commutated converter and the first line-commutated converter, the control device activates the first self-commutated converter, and after completion of activation of the first self-commutated converter, activates the first line-commutated converter, and
- when detecting a single or double line to ground fault inside the first line-commutated converter and detecting an occurrence of a missed zero crossing in a non-faulted phase of the first AC power system, the control device causes the first self-commutated converter to output a DC component for eliminating the missed zero crossing to the first AC power system, and then opens an AC circuit breaker in order to separate the first line-commutated converter from the first AC power system.
A control device of a power conversion system, the power conversion system including:
- a first self-commutated converter connected between
- a first AC power system, and
- a first DC main line and a DC return line for first high voltage DC transmission;
- a first line-commutated converter connected between
- the first AC power system, and
- the DC return line and a second DC main line for second high voltage DC transmission;
- a second self-commutated converter connected between
- a second AC power system, and
- the first DC main line and the DC return line;
- and
- a second line-commutated converter connected between
- the second AC power system, and
- the DC return line and the second DC main line,
- the control device comprising:
- a first control device to control the first self-commutated converter;
- a second control device to control the first line-commutated converter;
- and
- a common control device, wherein
- when detecting that voltage at the first AC power system is a zero voltage and that the voltage at the second AC power system is within a rated range, and activating the first self-commutated converter and the first line-commutated converter, the common control device issues an activation command of the first self-commutated converter to the first control device, and after completion of activation of the first self-commutated converter and after detecting that the voltage at the first AC power system is within the rated range, issues an activation command of the first line-commutated converter to the second control device.
Dependencies are inferred from the claim text.