Abstract:
A method and an apparatus for damping voltage oscillation of a voltage intermediate circuit of a frequency converter, the frequency converter comprising a half controlled rectifier bridge coupled to a supply network. The method comprises determining magnitude (Uc) of voltage of the voltage intermediate circuit, determining magnitude (Uin) of rectified voltage of the supply network, forming a derivative of a difference (Uin−Uc) between the rectified voltage of the supply network and the voltage of the voltage intermediate circuit, delaying firing of controllable components of the rectifier bridge on the basis of the formed derivative.
Abstract:
A mechanical construction of an electrical module includes two or more electrical components (102-105). Each of the electrical components has a contact surface (106-109) that is capable of forming a galvanic contact with an external electrical conductor. The electrical module includes a holder element (101) that includes flexible material arranged to flexibly support the electrical components with respect to each other in such a way that the contact surfaces of the electrical components are capable of aligning with external surfaces independently of each other.