An electric device (1) comprises a portion generating heat and a portion for dissipating said generated heat by heat exchange with a fluid, wherein said heat dissipating portion comprises means for generating a turbulent flow in the fluid.

An electric device (1) comprises a portion generating heat and a portion for dissipating said generated heat by heat exchange with a fluid, wherein said heat dissipating portion comprises means for generating a turbulent flow in the fluid.

The invention relates to a heavy-current transformer (12), in particular for a power source (10) in order to provide a welding current of a resistance welding device (1), with at least one primary winding (13) and at least one secondary winding (14) with center tapping, and to a transformer element, a contact plate (29) and a secondary winding (14) for such a heavy-current transformer (12) as well as a method for the manufacturing thereof. For reduction of losses and improvement of efficiency, at least four contacts (20, 21, 22, 23) are provided to form a multi-point contacting, said contacts (20, 21, 22, 23) being formed by four contact faces within which the at least one primary winding (13) and the at least one secondary winding (14) are arranged in a series/parallel connection.

The invention relates to a heavy-current transformer (12), in particular for a power source (10) in order to provide a welding current of a resistance welding device (1), with at least one primary winding (13) and at least one secondary winding (14) with center tapping, and to a transformer element, a contact plate (29) and a secondary winding (14) for such a heavy-current transformer (12) as well as a method for the manufacturing thereof. For reduction of losses and improvement of efficiency, at least four contacts (20, 21, 22, 23) are provided to form a multi-point contacting, said contacts (20, 21, 22, 23) being formed by four contact faces within which the at least one primary winding (13) and the at least one secondary winding (14) are arranged in a series/parallel connection.

Methods and apparatuses for cooling an electronic device assembly having a heat producing are described. An electronic device assembly includes a heat dissipation member and a dielectric two-phase heat transfer device. The dielectric heat transfer device has an evaporator region thermally attached to a hot region of the heat producing component and a condenser region thermally attached to the heat dissipation member. The dielectric two-phase heat transfer device is fabricated from a dielectric material.

Methods and apparatuses for cooling an electronic device assembly having a heat producing are described. An electronic device assembly includes a heat dissipation member and a dielectric two-phase heat transfer device. The dielectric heat transfer device has an evaporator region thermally attached to a hot region of the heat producing component and a condenser region thermally attached to the heat dissipation member. The dielectric two-phase heat transfer device is fabricated from a dielectric material.

A controllable primary switch for isolating a transformer from a power grid or network, wherein the controllable primary switch is mountable within and integral to the transformer and is electrically connected to high voltage feeder cables to allow the transformer to be disconnected from the power grid or network. The controllable primary switch includes one or more vacuum interrupters having first and second electrical switch contacts mounted inside the casing, actuator means for moving the second switch contact relative to the first switch contact in each of the one or more vacuum interrupters; and a handle connected to the actuator means, wherein said handle is capable of engaging the actuator means to move the second switch contact relative to the first switch contact.

A controllable primary switch for isolating a transformer from a power grid or network, wherein the controllable primary switch is mountable within and integral to the transformer and is electrically connected to high voltage feeder cables to allow the transformer to be disconnected from the power grid or network. The controllable primary switch includes one or more vacuum interrupters having first and second electrical switch contacts mounted inside the casing, actuator means for moving the second switch contact relative to the first switch contact in each of the one or more vacuum interrupters; and a handle connected to the actuator means, wherein said handle is capable of engaging the actuator means to move the second switch contact relative to the first switch contact.

A choke coil module of a high power density DC-AC power inverter includes a retainer. The retainer includes a lower plate and an upper plate. The upper and lower plates are spaced from each other and have two slots, respectively. An accommodation space of the retainer is provided with two choke coils which are disposed obliquely in a stagger manner. Top portions and bottom portions of the choke coils protrude out of and lean against the slots of the upper plate and the lower plate, respectively. The outside air is guided by a fan unit to enter a casing through air inlets, and the heat generated by the choke coils is expelled to the outside through air outlets. The choke coil module can be mounted in a smaller casing, such as a casing with a height of 2 U, to achieve excellent heat dissipation.

A choke coil module of a high power density DC-AC power inverter includes a retainer. The retainer includes a lower plate and an upper plate. The upper and lower plates are spaced from each other and have two slots, respectively. An accommodation space of the retainer is provided with two choke coils which are disposed obliquely in a stagger manner. Top portions and bottom portions of the choke coils protrude out of and lean against the slots of the upper plate and the lower plate, respectively. The outside air is guided by a fan unit to enter a casing through air inlets, and the heat generated by the choke coils is expelled to the outside through air outlets. The choke coil module can be mounted in a smaller casing, such as a casing with a height of 2 U, to achieve excellent heat dissipation.