Abstract: In a method for controlling bi-directional switches in power converters, with separate control signals for both current directions, preferably 3×3 matrix converters, a switching process from a base main state, into a secondary main state, and vice versa, occurs after a voltage controlled two-step process or a voltage controlled four-step process, without additional operational current-conducting components. After a first step, all uni-directional switches, apart from those at the interface of reference main state and target main state, are switched off and after a second step, all target main state switches are switched on. The switching processes can thus be carried out, at any time, by an appropriate choice of interval beginning and interval end, whereby a free-wheeling arm for both current directions permanently exists, the only requirement being the creation of a current interval for each phase in multi-phase systems. The method is applicable with practically all supply current frequencies.