| 摘要 |
The invention relates to a device and a method for detecting a foreign object in a spatial area. The method comprises the following steps: setting (S01) a capacitive element (12) which is electrically connected to a coil (10; 110) to a first capacitance value (C); applying (S02) an alternating voltage to the coil (10) by means of the capacitive element (12) which has the set first capacitance value (C) to generate a magnetic field (M) in a spatial area (V); varying (S03) a frequency (f) of the applied alternating voltage (S02) in a first predetermined frequency range; recording (S04) a first measurement curve (30-i, 31-i) for the first set capacitance value (C), said curve describing a first frequency-dependent parameter (32, 34) of the coil (10; 110) as a function of the varied frequency (f); and comparing (S05) at least the recorded first measurement curve (30-i, 31-i) with at least one reference profile, in order to determine whether at least one foreign object (F) is present in the spatial area (V). |
