Power converter and control method of power converter

A power converter comprising:

• a power converting unit configured to convert an input power and output a converted power;
• and
• a control unit configured to control a power conversion characteristic of the power converting unit based on a reference function having a droop characteristic that is defined according to an input value in any one of voltage control, power control, and current control corresponding to the droop characteristic, wherein
• the reference function is comprised of a plurality of droop functions having droop characteristics different from one another and connected,
• a control area is acquired for each of the plurality of droop functions to define a range of voltage, power, and current in which corresponding voltage control, power control, or current control is performed, for each of the droop functions,
• when an operating point determined by the input value is positioned on a droop function to perform voltage control, a control area is defined for each droop function of the plurality of droop functions, the control area being a neighborhood of the droop function for each droop function other than the droop function having the operating point, and the control area for the droop function having the operating point being all area not set as a control area for another droop function of the plurality of droop functions,
• when the operating point is positioned on a droop function to perform power control or current control, and the droop function is a droop characteristic of a constant power or a constant current, the control area is set such that a control corresponding to a connected droop function is performed when a voltage of the operating point exceeds a connection point of the droop function,
• when the operating point is positioned on a droop function to perform power control or current control, and the droop function is not a droop characteristic of a constant power or a constant current, the control area is set such that a control corresponding to a connected droop function is performed when a power of the operating point exceeds a connection point of the droop function,
• a control mechanism of the power conversion characteristic is set for any one of the voltage control, power control, and current control based on the control area and the operating point, and
• when the operating point moves from a first control area corresponding to a first droop function to a second control area corresponding to a second droop function the control areas for each of the plurality of droop functions are changed according to the second droop function.

A control method of a power converter, comprising:

• a control step of controlling a power conversion characteristic of the power converter based on a reference function having a droop characteristic that is defined according to an input value, in any one of voltage control, power control, and current control corresponding to the droop characteristic, wherein
• the reference function is constituted of a plurality of droop functions having droop characteristics different from one another and connected at a connection point, and comprising:
• a step of acquiring a control area to define a range of voltage and power in which corresponding voltage control, power control, or current control is performed for each of a plurality of droop functions;
• a step of changing, when an operating point determined by the input value moves from a first control area corresponding to a first droop function to a second control area corresponding to a second droop function the control areas for each of the plurality of droop functions according to the second droop function;
• a step of setting a control method of the power conversion characteristic based on the control area and the operating point for any one of voltage control, power control, and current control, wherein
• the control area is set, when an operating point determined by the input value fluctuates to deviate from the plurality of droop functions, such that the operating point is not converged at a position outside a range defined at the connection point in the droop function, and any one of fluctuation amount and fluctuation frequency of voltage, power, or current are minimized until the operating point is converged on the droop function.

A control method of a power converter, comprising:

• a control step of controlling a power conversion characteristic of the power converter based on a reference function having a droop characteristic that is defined according to an input value, in any one of voltage control, power control, and current control corresponding to the droop characteristic, wherein
• the reference function is comprised of a plurality of droop functions having droop characteristics different from one another and connected,
• a step of setting a control mechanism of the power conversion characteristic based on a control area of a droop function of the plurality of droop functions and an operating point for any one of voltage control, power control, and current control;
• a step of changing, when an operating point determined by the input value moves from a first control area corresponding to a first droop function to a second control area corresponding to a second droop function the control areas for each of the plurality of droop functions according to the second droop function;
• and
• a step of setting a control method of the power conversion characteristic based on the control area and the operating point for any one of voltage control, power control, and current control,
• when the operating point is positioned on a droop function to perform voltage control, a control area is defined for each function of the plurality of droop functions, the control area being a neighborhood of the droop function for each droop function of the plurality of droop functions other than the droop function having the operating point, and the control area for the droop function having the operating point being all area not set as a control area for another droop function of the plurality of droop functions,
• when the operating point is positioned on a droop function to perform power control or current control, and the droop function is a droop characteristic of a constant power or a constant current, the control area is set such that a control corresponding to a connected droop function is performed when a voltage of the operating point exceeds a connection point of the droop function,
• when the operating point is positioned on a droop function to perform power control or current control, and the droop function is not a droop characteristic of a constant power or a constant current, the control area is set such that a control corresponding to a connected droop function is performed when a power of the operating point exceeds a connection point of the droop function.