Various embodiments of the teachings herein include an apparatus for voltage equalization in square-wave voltages of electric motors. The apparatus may include: a terminal board circuit wherein phases U, V, and W each comprises input and output cabled conductors summing to at least 6 cables; and a bridge between two of the at least six cables connecting two or more of the at least 6 cable inputs and outputs. The bridge is partially conductive such that its electrical resistance markedly reduces above a threshold value. The partial conductivity results from filler particles in an embedding matrix determining a reduction of the resistance in the bridge above the threshold value.

A transient voltage protection device includes: an element body; a cavity portion provided in the element body; a pair of internal electrodes disposed in the element body; and a pair of external electrodes connected to the pair of internal electrodes. The pair of internal electrodes extend along a first direction and face each other in a second direction intersecting the first direction. The cavity portion includes a gap region located between the pair of internal electrodes in the second direction. A tip portion of at least one of the pair of internal electrodes is in contact with only the element body.

A multilayer varistor has a stack structure including a plurality of layers stacked in a third direction. The multilayer varistor includes a first internal electrode electrically connected to a first external electrode, a second internal electrode electrically connected to the second external electrode, and a third internal electrode electrically connected to the third external electrode. The first internal electrode is disposed between the second internal electrode and the third internal electrode in the third direction.

A multilayer varistor has a stack structure including a plurality of layers stacked in a third direction. The multilayer varistor includes a first internal electrode electrically connected to a first external electrode, a second internal electrode electrically connected to the second external electrode, and a third internal electrode electrically connected to the third external electrode. The first internal electrode is disposed between the second internal electrode and the third internal electrode in the third direction.

The present invention relates to a polymer voltage-dependent resistor (PVDR) in various physical forms and methods for manufacturing the varistor. The body of the PVDR is composed of a polymer matrix having a filler composed of doped zinc oxide particles, other semi conductive particles or metal particles uniformly distributed therein. Conductive electrodes may be affixed to the polymer matrix and electrical leads attached to the electrodes.

A multilayer varistor includes a sintered body, an internal electrode disposed in the sintered body, a high-resistance layer covering at least part of the sintered body, and an external electrode covering part of the high-resistance layer, the external electrode being electrically connected to the internal electrode. An arithmetic mean roughness of a surface of the high-resistance layer is greater than or equal to 0.06 μm.

A multilayer varistor includes a sintered body, an internal electrode disposed in the sintered body, a high-resistance layer covering at least part of the sintered body, and an external electrode covering part of the high-resistance layer, the external electrode being electrically connected to the internal electrode. An arithmetic mean roughness of a surface of the high-resistance layer is greater than or equal to 0.06 μm.

A low-voltage varistor includes a cured body of a resin composition for forming the low-voltage varistor. The resin composition includes: (A) at least one selected from carbon nanotubes and carbon aerogels; and (B) at least one selected from epoxy resin and acrylic resin.

Provided according to embodiments of the invention are varistor ceramic formulations that include zinc oxide (ZnO). In particular, varistor ceramic formulations of the invention may include dopants including an alkali metal compound, an alkaline earth compound, an oxide of boron, an oxide of aluminum, or a combination thereof. Varistor ceramic formulations may also include other metal oxides. Also provided according to embodiments of the invention are varistor ceramic materials formed by sintering a varistor ceramic formulation according to an embodiment of the invention. Further provided are varistors formed from such ceramic materials and methods of making such materials.

For a carrier plate, it is proposed to brace a first ceramic functional layer over a connecting layer (VS) with a ceramic stressing layer (SPS) in order to reduce the lateral sintering shrinkage. The functional layer (FS) and the stressing layer (SPS) are glass-free or have only a small glass content of less than 5 wt %, whereas the connecting layer (VS) comprises a glass component or is a glass layer.