Electrical circuit arrangement, which is supplied from a DC voltage source, for supplying a load two-pole network with a direct current which is impressed but can be interrupted or a block-form alternating current which is impressed but can be interrupted, with adjustable limiting of the voltages on the load two-pole network and on the electronic one-way switches which are used

摘要

Electrical load two-pole networks must be supplied in many applications (for example in the case of electrical welding, spark erosion or the excitation of lasers) with an impressed direct current or alternating current, which would frequently be capable of being pulsed. In order to impress a current, circuit arrangements which have been widespread until now use either a bias resistor, which results in poor efficiency, or an inductor in the output circuit, which severely constrains the pulsing capability. These disadvantages are avoided in the basic arrangement according to the invention, which is shown by way of example in Fig. 4. The current through the load two-pole network (1) is impressed with the aid of an input step-down controller (7). If it is not intended to supply any power to the load two-pole network, the short-circuiting switch (5) must be closed. When the short-circuiting switch is blocked, the voltage on the load two-pole network and on the short-circuiting switch is limited by a buffering network (12). The voltage on the buffering capacitor is regulated at a preferably constant setting by suitably influencing a feedback controller (15). If an invertor is introduced between the output terminals of the circuit arrangement according to Fig. 4 and the load two-pole network, the load two-pole network can be supplied with an impressed, block-form alternating current. In addition, it is possible to design the circuits to be isolated in terms of potential. IMAGE