Power converter apparatus applied to wind power generation system
View Patent ↗There is provided a power converter apparatus including a detector detecting a system voltage, and a controller stably outputting power generated by the wind power generator to the power system based on a power instruction value and controlling an output voltage to stabilize the system voltage based on a voltage instruction value in a case where the system voltage is within a preset range, and controlling an active current component and a reactive current component of an output current to stabilize the system voltage of the power system by use of a voltage drop due to impedance of the power system in a case where the system voltage is outside the preset range.
1. A power converter apparatus that is applied to a wind power generation system and converts power generated by a wind power generator to alternating-current power supplied for a power system, the power converter apparatus comprising:
a system voltage detector configured to detect a system voltage of the power system;
a converter controller configured to be exclusively controlled by an alternating-current detected from the wind power generator, generate a power instruction value and a gate signal only based on the alternating-current and input the generated gate signal to a converter that converts the alternating-current to a direct-current:
an inverter controller configured to receive the generated power instruction value from the converter controller; and
an inverter configured to convert the direct-current converted by the converter to the alternating-current power supplied for the power system,
wherein the inverter controller is configured to control the inverter to stably output power generated by the wind power generator to the power system based on another power instruction value from a higher level controller and to control an output voltage of the inverter to stabilize the system voltage of the power system based on an alternating-current voltage instruction value when the system voltage detected by the system voltage detector is within a preset range having an upper limit and a lower limit, and configured to control an output current of the inverter such that an active current component and a reactive current component are those corresponding to a variation rate of the system voltage to stabilize the system voltage of the power system by use of a voltage drop due to impedance of the power system when the system voltage detected by the system voltage detector is outside the preset range.
2. The power converter apparatus according to claim 1 , wherein the impedance of the power system is simulated by a resistance component and a reactance component.
3. The power converter apparatus according to claim 2 , wherein
the converter controller is configured to calculate the power instruction value and controls the converter; and
the inverter controller is configured to control the inverter based on the power instruction value calculated by the converter controller when the system voltage is within the preset range.
4. The power converter apparatus according to claim 1 , wherein
the converter controller is configured to calculate the power instruction value and controls the converter; and
the inverter controller is configured to control the inverter based on the power instruction value calculated by the converter controller when the system voltage is within the preset range.
5. A control method of controlling a power converter apparatus that is applied to a wind power generation system and converts power generated by a wind power generator to alternating-current power supplied for a power system, the control method comprising:
detecting a system voltage of the power system;
controlling a converter controller of the power converter apparatus exclusively by an alternating-current detected from the wind power generator;
generating a power instruction value and a gate signal only based on the alternating-current;
inputting the generated gate signal to a converter that converts the alternating-current to a direct-current;
receiving, by an inverter controller, the generated power instruction value from the converter controller;
converting, by an inverter, the direct-current converted by the converter to the alternating-current power supplied for the power system; and
stably outputting, by the inverter controller, power generated by the wind power generator to the power system based on another power instruction value from a higher level controller and controlling an output voltage of the inverter to stabilize the system voltage of the power system based on an alternating-current voltage instruction value when the system voltage detected is within a preset range having an upper limit and a lower limit, and controlling an output current of the inverter such that an active current component and a reactive current component are those corresponding to a variation rate of the system voltage to stabilize the system voltage of the power system by use of a voltage drop due to impedance of the power system when the system voltage detected is outside the preset range.