Abstract: A wheel bearing includes a rotary element mounted on the wheel and configured to rotate together with the wheel; a non-rotary element fixedly mounted on the vehicle body; one or more rolling bodies provided between the rotary element and the non-rotary element; a sensor target mounted on the rotary element and configured to rotate together with the rotary element; and a wheel speed sensor disposed adjacent to the sensor target to sense a rotational speed of the rotary element. The wheel speed sensor may include a first sensing part and a second sensing part configured to sense a change in magnetic field caused by the rotation of the sensor target, and the second sensing part may be disposed to be spaced apart from the first sensing part in longitudinal and widthwise directions of the wheel speed sensor.

Abstract: A power control method for controlling power of a plurality of power conversion modules that are respectively connected in parallel to a plurality of photovoltaic, includes: sensing a string current value flowing between outermost opposite ends of the plurality of photovoltaic modules, and voltage and current values of each of the photovoltaic modules; changing the string current value and respectively calculating conversion power values of the plurality of power conversion modules per the changed string current value by using the voltage and current values; searching a string current value for a minimum power point tracking control among the changed string current values by using the conversion power values; and controlling the plurality of power conversion modules to track the searched string current value.

Abstract: A power control method for controlling power of a plurality of power conversion modules that are respectively connected in parallel to a plurality of photovoltaic, includes: sensing a string current value flowing between outermost opposite ends of the plurality of photovoltaic modules, and voltage and current values of each of the photovoltaic modules; changing the string current value and respectively calculating conversion power values of the plurality of power conversion modules per the changed string current value by using the voltage and current values; searching a string current value for a minimum power point tracking control among the changed string current values by using the conversion power values; and controlling the plurality of power conversion modules to track the searched string current value.