It is possible to establish an estimation method capable of logically and optimally deciding a forgetting coefficient and develop an estimation algorithm and a high-speed algorithm which are numerically stable. With known methods, electromagnetic valves are triggered with a pulse-width-modulated signal having a constant clock frequency. The method also includes storing the encrypted data at the distributor and generating a message by further encrypting the encrypted data using an encryption transmission key. The power transmission unit receives and tracks a power request signal from the power receiver system to track the power receiver system location during energy transmission. This processing, which can be realized by activation of software, improves audio quality when compressed audio data is replayed. The spherical valve closing body is secured on the closing body carrier in a non-positive manner due to the shape of the corresponding connecting surfaces.