Abstract: A matrix converter apparatus for wind-power generation according to an embodiment includes a matrix converter and a controller. The controller adds information about a voltage phase of the power grid or information about a voltage phase of the generator to a power-grid-side power factor to generate information about a current phase, and generates a control signal for controlling the matrix converter based on the information about the current phase.

Abstract: There is provided a user interface with which a greater number of processes are executable in response to user operations made to a directional input device. When the directional input device receives a first direction followed by a second direction within a predetermined time period, the amount of change from the first direction to the second direction is calculated. If the calculated change amount exceeds a predetermined range, a first processes associated with each of the first and second directions is performed. If the calculated change amount falls within the predetermined range, a second process associated with the change amount is performed.