Abstract: Semiconductor switch modules have positive and negative electrical input connections which must be spaced adequately to prevent a short circuit flashover between the polarities. This terminal spacing is defined by the strike distance through air or creepage distance through air along an insulating surface between the two input connections given the operating voltage per regulatory agency requirements. The inductance of the switch connections is ultimately limited by this terminal spacing. A novel conformal solid insulation scheme between the bus structure and switch module eliminates the strike or creepage paths through air and allows for reduced terminal spacing and lower inductance while meeting regulatory agency requirements.

Abstract: With respect to the construction and manufacture of well known prior art metallized polymer film capacitors, a technique is described to mitigate the effects of cracks that may develop in the arc sprayed metal connections to the capacitor electrodes when the capacitor diameter becomes large.

Abstract: A technique is described for increasing the capacitance of a metallized polymer film capacitor where the capacitor electrodes have been fabricated with so-called patterned film. The pattern as typically embodied by prior art allows the capacitor to better survive dielectric failures, or exhibit improved tolerance to extreme pulse current. The pattern is created by areas on the capacitor electrodes which have no metal, so there will be a capacitance reduction penalty for using said patterned electrodes. Each section of the pattern is connected by a local fuse, which is disconnected from the rest of the capacitor when the current flowing through a defect vaporizes the surrounding metal. An extremely light metallization underlayer is described which allows the better survival characteristic provided by pattern film should a dielectric failure occur, yet mitigates the capacitance loss previously seen for capacitors made with conventional patterned metallized electrodes on the capacitor film.

Abstract: Parallel plate bus structures are commonly used for high-current applications where low inductance is a requirement. Such bus structures are very well suited for inverter topologies used to convert from DC to AC power and a capacitor is needed to minimize ripple on the DC bus. However, such arrangements are not able to provide sufficiently low inductance to easily eliminate bypass capacitors which typically requires a system inductance below 10 nH nor do they provide any natural EMI suppression. The present invention utilizes that natural circular symmetry of a circular film capacitor winding by implementing a coaxial shaped bus connection from the capacitor to the switching semiconductors in the DC bus application of DC to AC inverter. The result is an achievement of lower ESL and geometry based EMI suppression without the use of external-lumped filtering components.

Abstract: Parallel plate bus structures are commonly used for high-current applications where low inductance is a requirement. Such bus structures are very well suited for inverter topologies used to convert from DC to AC power and a capacitor is needed to minimize ripple on the DC bus. The present invention provides a method of integrating an annular form factor wound film capacitor into a parallel bus structure to provide a compact geometry with minimal inductance. Furthermore, the capacitor acts as the dielectric spacer between the bus plates, which eliminates the need for separate capacitor terminals and provides the lowest possible profile.

Abstract: The formation of an assembled unit consisting of an annular capacitor [a wound, metallized dielectric capacitor in the shape of a closed path ring] with other power conversion components arranged and attached in manners uniquely allowed by the ring design will allow higher density converter designs [power/unit volume]. The resulting short connection paths between the capacitor element and the switching semiconductors also provide a very low inductance path that minimizes voltage spikes on the switching semiconductors as a result of turn-off di/dt. The capacitor serves as a short time current source and sink for the switching semiconductors. With the described configuration the RMS current seen by the capacitor can be made more volumetrically uniform enabling more uniform capacitor rise. The single capacitor configured as described also mitigates bus resonance problems often observed in prior art when multiple discrete capacitors are connected in parallel.

Abstract: An exemplary embodiment providing one or more improvements includes a capacitor with a segmented end electrode and methods for segmenting an end electrode of a capacitor for reducing or eliminating instances of thermally induced damage of the capacitor.

Abstract: An exemplary embodiment providing one or more improvements includes a capacitor with a segmented end electrode and methods for segmenting an end electrode of a capacitor for reducing or eliminating instances of thermally induced damage of the capacitor.

Abstract: An exemplary embodiment providing one or more improvements includes a capacitor with a segmented end electrode and methods for segmenting an end electrode of a capacitor for reducing or eliminating instances of thermally induced damage of the capacitor.

Abstract: An improved electrical terminal attachment process for a wound polymer film/foil or metallized film capacitor is described that minimizes thermal damage to the capacitor structure and improves the current carrying capability of the capacitor. The process employs an electrically conductive adhesive that can be cured at low temperatures. The disclosed process improves the reliability of the capacitor when used at high RMS or pulsed currents. It also enables capacitor application structures with reduced equivalent series inductance that would be otherwise difficult or impossible to fabricate.

Abstract: An exemplary embodiment providing one or more improvements includes a capacitor with a segmented end electrode and methods for segmenting an end electrode of a capacitor for reducing or eliminating instances of thermally induced damage of the capacitor.

Abstract: A modified capacitor for replacing an unmodified capacitor includes two unmodified metallized strips, each supported by an unmodified dielectric film arrangement that is made up of two dielectric films. Each unmodified metallized strip has an elongated length and includes an unmodified active region and a lengthwise unmodified, heavy-edge region. The two dielectric films are wound together to form a roll having opposing ends such that the lengthwise unmodified, heavy-edge region of each unmodified metallized strip cooperate in forming the opposing ends for external electrical connection thereto. The unmodified capacitor exhibits a given value of pulse current tolerance.

Abstract: A wound, metallized dielectric film capacitor for pulsed power applications is disclosed. The capacitor consists of a wound metallized polymer film in the shape of a closed path ring. The electrical load is placed within the inner opening of the capacitor. The capacitor has low inductance and resistance, scales to high energy levels, and can be formed around the electrical load.

Abstract: A means of increasing the corona inception voltage (CIV), and thereby increasing the operating voltage, of film/foil capacitors is described. Intentional venting of the capacitor encapsulation improves the corona inception voltage by allowing internal voids to equilibrate with the ambient environment.