Abstract: An electronic appliance such as a low harmonic drive, an active rectifier, a grid converter or any active front end or grid converter with an LCL filter. The converter is a two-level, a three-level or a multilevel inverter. The electronic appliance includes an LCL filter on a grid side of the electronic appliance and an active front end rectifier provided on a load side of the electronic appliance. The LCL filter includes grid side inductors and an active front end rectifier is connected to the LCL filter. A method for damping a corresponding electronic appliance is also disclosed.

Abstract: A method for cooling a device such as an electric motor drive or a general power converter, said device comprising a heatsink, electronic components connected to the heatsink, a heat pipe connected to the heatsink, an inlet air temperature measuring device and a cooling fan. According to the method, the drive establishes whether the inlet air temperature is below a first temperature threshold value and operates the cooling fan at a low inlet air temperature speed regime if the inlet air temperature is below the first temperature threshold value. The invention is also directed at a device such as an electric motor drive or a general power converter for performing the cooling method.

Abstract: A controller (203) comprises a processing system (205) for controlling a power electronic converter during a short circuit taking place in a direct voltage side of the power electronic converter. The processing system recognizes a direction of current in a phase (126-128) of an alternating voltage side of the power electronic converter, sets a high-leg controllable switch (108-110) of the phase to a conductive state while keeping a low-leg controllable switch (111-113) of the phase in a non-conductive state when the recognized direction of the current is outwards from the power electronic converter, and otherwise sets the low-leg controllable switch to the conductive state while keeping the high-leg controllable switch in the non-conductive state. Thermal loadings of freewheeling diodes (114-119) of the power electronic converter are reduced since currents needed to burn input fuses (122) of the power electronic converter are shared between the controllable switches and the freewheeling diodes.

Abstract: A filter arrangement in connection with a power converter for transferring power between a multiphase AC voltage network and a DC voltage network. The filter arrangement comprises a differential mode coil coupled between each AC terminal of an inverter bridge and corresponding AC network phase terminal, and a common mode coil coupled between each inverter bridge DC terminal and corresponding DC network terminal. Both inductors are located in the same magnetic core structure such that each of the differential mode winding is wound around its own phase-specific core leg and all common mode windings are wound around their own single core leg. The winding direction of both AC- and DC-side inductor windings is such that a common-mode current which flows along both inductors in the same direction, induces in each magnetic core leg a flux which reinforces the total flux circulating in the magnetic core.

Abstract: The present invention relates to an electronic appliance, in particular a low harmonic drive, an active rectifier, a grid converter and/or any active front end or grid converter with an LCL filter. The converter may be a two-level, a three-level or a multilevel inverter. The electronic appliance includes an LCL filter on its grid side and an active front end rectifier provided on its load side. The LCL filter includes grid side inductors and the active front end rectifier is connected to the LCL filter. The present invention also relates to a method for damping a corresponding electronic appliance.

Abstract: An inductor assembly for use in a power converter for transferring power between a DC voltage network and a multiphase AC voltage network. The inductor assembly comprises a core for guiding magnetic flux and coils for generating magnetic flux wherein the core has first legs with differential mode coil wires wound around the first legs and at least one second leg with at least two common mode coil wires wound around said second leg. The winding direction of both AC- and DC-side coils is such that a common-mode electrical current which flows in both coils in the same direction induces in each core leg a magnetic flux which reinforces the total flux circulating in the core.

Abstract: A filter arrangement in connection with a power converter for transferring power between a multiphase AC voltage network and a DC voltage network. The filter arrangement comprises a differential mode coil coupled between each AC terminal of an inverter bridge and corresponding AC network phase terminal, and a common mode coil coupled between each inverter bridge DC terminal and corresponding DC network terminal. Both inductors are located in the same magnetic core structure such that each of the differential mode winding is wound around its own phase-specific core leg and all common mode windings are wound around their own single core leg. The winding direction of both AC- and DC-side inductor windings is such that a common-mode current which flows along both inductors in the same direction, induces in each magnetic core leg a flux which reinforces the total flux circulating in the magnetic core.

Abstract: A controller (203) comprises a processing system (205) for controlling a power electronic converter during a short circuit taking place in a direct voltage side of the power electronic converter. The processing system recognizes a direction of current in a phase (126-128) of an alternating voltage side of the power electronic converter, sets a high-leg controllable switch (108-110) of the phase to a conductive state while keeping a low-leg controllable switch (111-113) of the phase in a non-conductive state when the recognized direction of the current is outwards from the power electronic converter, and otherwise sets the low-leg controllable switch to the conductive state while keeping the high-leg controllable switch in the non-conductive state. Thermal loadings of freewheeling diodes (114-119) of the power electronic converter are reduced since currents needed to burn input fuses (122) of the power electronic converter are shared between the controllable switches and the freewheeling diodes.

Abstract: Non-linear inductor(s) are used to reduce the percent total harmonic distortion of the harmonics in the line currents in the input side rectifier system of an ac drive system. Several constructions for the non-linear inductor(s) are described. The non-linear inductor(s) may be constructed from E and I laminations. The gap depends on the construction of the middle leg of the E laminations and may have a step with a constant spacing or a variable spacing which depends on the stacking of the laminations. Alternatively the non-linear inductor(s) may be constructed from a toriodal core that either has a step gap or a variable type gap.

Abstract: Non-linear inductor(s) are used to reduce the percent total harmonic distortion of the harmonics in the line currents in the input side rectifier system of an ac drive system. Several constructions for the non-linear inductor(s) are described. The non-linear inductor(s) may be constructed from E and I laminations. The gap depends on the construction of the middle leg of the E laminations and may have a step with a constant spacing or a variable spacing which depends on the stacking of the laminations. Alternatively the non-linear inductor(s) may be constructed from a toriodal core that either has a step gap or a variable type gap.

Abstract: Non-linear inductor(s) are used to reduce the percent total harmonic distortion of the harmonics in the line currents in the input side rectifier system of an ac drive system. Several constructions for the non-linear inductor(s) are described. The non-linear inductor(s) may be constructed from E and I laminations. The gap depends on the construction of the middle leg of the E laminations and may have a step with a constant spacing or a variable spacing which depends on the stacking of the laminations. Alternatively the non-linear inductor(s) may be constructed from a toriodal core that either has a step gap or a variable type gap.

Abstract: Non-linear inductor(s) are used to reduce the percent total harmonic distortion of the harmonics in the line currents in the input side rectifier system of an ac drive system. Several constructions for the non-linear inductor(s) are described. The non-linear inductor(s) may be constructed from E and I laminations. The gap depends on the construction of the middle leg of the E laminations and may have a step with a constant spacing or a variable spacing which depends on the stacking of the laminations. Alternatively the non-linear inductor(s) may be constructed from a toriodal core that either has a step gap or a variable type gap.

Abstract: Non-linear inductor(s) are used to reduce the percent total harmonic distortion of the harmonics in the line currents in the input side rectifier system of an ac drive system. Several constructions for the non-linear inductor(s) are described. The non-linear inductor(s) may be constructed from E and I laminations. The gap depends on the construction of the middle leg of the E laminations and may have a step with a constant spacing or a variable spacing which depends on the stacking of the laminations. Alternatively the non-linear inductor(s) may be constructed from a toriodal core that either has a step gap or a variable type gap.

Abstract: Non-linear inductor(s) are used to reduce the percent total harmonic distortion of the harmonics in the line currents in the input side rectifier system of an ac drive system. Several constructions for the non-linear inductor(s) are described. The non-linear inductor(s) may be constructed from E and I laminations. The gap depends on the construction of the middle leg of the E laminations and may have a step with a constant spacing or a variable spacing which depends on the stacking of the laminations. Alternatively the non-linear inductor(s) may be constructed from a toriodal core that either has a step gap or a variable type gap.