Abstract: The maximum electrical power drawn from an electrical power source by a mining excavator comprising electric motors is reduced by supplying supplementary electrical power from an electrical energy storage unit. The input electrical power drawn by the mining excavator is cyclic. An upper limit is set for the electrical power drawn from the electrical power source. When the input electrical power drawn by the mining excavator exceeds the upper limit, electrical power is supplied by the electrical energy storage unit, such as an ultracapacitor bank. The ultracapacitor bank may be charged by the electrical power source during off-peak intervals. Electrical power generated by electrical motors operating in a regeneration interval may also be recaptured and stored in the electrical energy storage unit.

Abstract: A diesel-electric drive system includes a generator having two multi-phase winding systems, a diesel engine, and a DC-link converter. Two self-commuted pulse power converters on the generator side are linked to the windings systems and to each other by a brake resistor on the alternating voltage side. The brake resistor is split into two series-connected resistors, each having half the resistance value of the brake resistor. An input of a bipolar switching device is connected to a connecting point of two series-connected resistors. The capacity of the diesel motor can then be checked in a self-load test with a controllable load torque of the diesel-electric drive system, while eliminating overloads of the power semiconductors of the self-commuted pulse power converters on the generator side.

Abstract: The maximum electrical power drawn from an electrical power source by a mining excavator comprising electric motors is reduced by supplying supplementary electrical power from an electrical energy storage unit. The input electrical power drawn by the mining excavator is cyclic. An upper limit is set for the electrical power drawn from the electrical power source. When the input electrical power drawn by the mining excavator exceeds the upper limit, electrical power is supplied by the electrical energy storage unit, such as an ultracapacitor bank. The ultracapacitor bank may be charged by the electrical power source during off-peak intervals. Electrical power generated by electrical motors operating in a regeneration interval may also be recaptured and stored in the electrical energy storage unit.

Abstract: The invention relates to an attenuation element. According to the invention, this attenuation element has two rail pieces (46, 48) and two conducting pieces (50, 52), wherein a rail piece (46, 48) and a conducting piece (50, 52) each are electrically connected in parallel, wherein these rail pieces (46, 48) are spatially disposed in parallel at a distance from each other, and wherein the conducting pieces (50, 52) each are made of electrically highly conductive material, and the rail pieces (46, 48) each are made of an electrically poorly conductive material. In this manner, the high-frequency currents can be substantially attenuated in a rectifier having distributed intermediate voltage circuits without the power loss in the intermediate voltage circuit markedly increasing such that the capacitors (10, 12, 24, 28) of the rectifier having distributed intermediate voltage circuits no longer need to be oversized with regard to an RMS current of the intermediate voltage circuit of this rectifier.

Abstract: The maximum electrical power drawn from an electrical power source by a mining excavator comprising electric motors is reduced by supplying supplementary electrical power from an electrical energy storage unit. The input electrical power drawn by the mining excavator is cyclic. An upper limit is set for the electrical power drawn from the electrical power source. When the input electrical power drawn by the mining excavator exceeds the upper limit, electrical power is supplied by the electrical energy storage unit, such as an ultracapacitor bank. The ultracapacitor bank may be charged by the electrical power source during off-peak intervals. Electrical power generated by electrical motors operating in a regeneration interval may also be recaptured and stored in the electrical energy storage unit.

Abstract: The invention relates to a diesel-electric drive system, comprising a generator (4) having two multi-phase winding systems (22, 24), a diesel engine (2), and a DC-link converter (6), the two self-commuted pulse power converters (10, 12) on the generator side of which are linked to said windings systems (22, 24) of the generator (4) and to each other by means of a brake resistor (30) on the alternating voltage side. According to the invention, two electrically series-connected resistors (48, 50) are provided as the brake resistor (30), the resistance values thereof corresponding to half of the resistance value of the brake resistor (30), and a bipolar switching device (54) is provided, which is connected on the input side to a connecting point (52) of two electrically series-connected resistors (48, 50).

Abstract: The maximum electrical power drawn from an electrical power source by a mining excavator comprising electric motors is reduced by supplying supplementary electrical power from an electrical energy storage unit. The input electrical power drawn by the mining excavator is cyclic. An upper limit is set for the electrical power drawn from the electrical power source. When the input electrical power drawn by the mining excavator exceeds the upper limit, electrical power is supplied by the electrical energy storage unit, such as an ultracapacitor bank. The ultracapacitor bank may be charged by the electrical power source during off-peak intervals. Electrical power generated by electrical motors operating in a regeneration interval may also be recaptured and stored in the electrical energy storage unit.

Abstract: The invention relates to an attenuation element. According to the invention, this attenuation element has two rail pieces (46, 48) and two conducting pieces (50, 52), wherein a rail piece (46, 48) and a conducting piece (50, 52) each are electrically connected in parallel, wherein these rail pieces (46, 48) are spatially disposed in parallel at a distance from each other, and wherein the conducting pieces (50, 52) each are made of electrically highly conductive material, and the rail pieces (46, 48) each are made of an electrically poorly conductive material. In this manner, the high-frequency currents can be substantially attenuated in a rectifier having distributed intermediate voltage circuits without the power loss in the intermediate voltage circuit markedly increasing such that the capacitors (10, 12, 24, 28) of the rectifier having distributed intermediate voltage circuits no longer need to be oversized with regard to an RMS current of the intermediate voltage circuit of this rectifier.