Power converter, diagnostic system of power converter, and diagnostic method
AssigneeHitachi, Ltd.
InventorsJunichi SAKANO, Kimihisa FURUKAWA, Takashi OGAWA, Hisashi ENDOU
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Abstract
There is provided a diagnostic system for a power converter which includes a semiconductor device, and performs a switching operation between conduction and interruption of the principal current flowing through the main circuit. The diagnostic system includes a current change amount calculation circuit for obtaining numeric data which reflects a current change amount of the principal current per unit time, a determination circuit for determining a state of the power converter by comparing the numeric data with a reference value, and an output circuit for outputting a determination result of the determination circuit.
Claims15
A diagnostic system for a power converter which includes a semiconductor device, and performs a switching operation between conduction and interruption of a principal current flowing through a main circuit, comprising:
- a current change amount calculation circuit for obtaining numeric data which reflects a current change amount of the principal current per unit time;
- a determination circuit for determining a state of the power converter by comparing the numeric data with a reference value;
- and
- an output circuit for outputting a determination result of the determination circuit.
A power converter comprising a current change amount calculation section for calculating a current change amount within a predetermined time period in a switching operation between conduction and interruption of a principal current flowing through a main circuit constituted by a power semiconductor, or a time needed for transition of a predetermined current change amount,
- wherein a comparative determination is made whether or not the current change amount or the time needed for transition deviates from a reference value;
- and
- at least one of operations to display a determination result, output the determination result, and control an operation condition of a switching element as the power semiconductor in accordance with the determination result is conducted.
A diagnostic method of a power converter which includes a semiconductor switching element for a switching operation between conduction and interruption of a principal current, comprising:
- a first step of detecting a current change amount of the principal current per unit time;
- a second step of integrating the current change amount through a digital circuit or an analog circuit for a predetermined time period;
- and
- a third step of determining a state of the power converter based on a result of the integration.
Dependencies are inferred from the claim text.