Patent application number | Description | Published |
20100157639 | Inverter Comprising Normally Conductive Gate-Controlled Semiconductor Switches - An inverter comprises two input lines; an inverter bridge connected between the input lines and including at least one half-bridge comprising two normally conductive gate-controlled semiconductor switches; a controller which supplies control voltages to the gates of the semiconductor switches in an operative state of the inverter; and a DC voltage source for supplying an auxiliary control voltage to the gates of the semiconductor switches in an inoperative state of the inverter so as to hold the inverter bridge in a non-conductive state between the input lines. The DC voltage source has a charging unit connected between the input lines in series with a further normally conductive gate-controlled semiconductor switch, o and charging a storage unit for electric charge, which is connected to the gate of the further semiconductor switch such that this switch becomes non-conductive, when the storage unit has been sufficiently charged for providing the auxiliary control voltage. | 06-24-2010 |
20100226160 | Power Generation System and Inverter for Feeding Power Into a Three-Phase Grid - A power generation system for feeding electrical power from a generation unit into a three-phase grid via three AC terminals is disclosed. The system includes a relay arrangement for disconnecting the system from the grid having at least three relays. Each of the three relays includes a control coil and two switching contacts operated by the corresponding control coil. Each of the AC terminals is connectable to the grid via a first and a second switching contact, each of which is assigned to a different one of the relays. Further disclosed are a relay arrangement and an inverter with a relay arrangement. | 09-09-2010 |
20110199792 | Converter Comprising at least one Normally on Semiconductor Switch - A converter for converting a DC input voltage includes two input lines receiving the DC input voltage; at least one normally off semiconductor switch which is not conductive without application of a control voltage to its gate and which is provided in one of the input lines. The converter also includes electric circuitry connected between the input lines and including at least one normally on semiconductor switch which is conductive without application of a control voltage to its gate; and a controller. In operation of the converter, the controller operates the at least one normally on semiconductor switch of the electric circuitry by temporarily applying a first control voltage to its gate; and permanently applies a second control voltage to the gate of the at least one normally off semiconductor switch in the one input line. Any normally on semiconductor switch of the electric circuitry is spatially separated and thus thermally isolated from any normally off semiconductor switch. | 08-18-2011 |
20120112800 | Method of and Driver Circuit for Operating a Semiconductor Power Switch - To operate a semiconductor power switch having a control electrode and a reference electrode in response to first and second switching commands, a control voltage between a first electric pole and a second electric pole is provided. Upon each first switching command, the control electrode is coupled to the first electric pole, and the reference electrode is coupled to the second electric pole; and upon each second switching command, the control electrode is coupled to the second electric pole, and the reference electrode is coupled to the first electric pole. Upon each switching command, continuously transitioning an electric potential of the one of the control and reference electrodes during a first transition period, and continuously transitioning an electric potential of the respective other of the control and reference electrodes during a second transition period occurs, wherein the first transition period beginning before and ending after the second transition period. | 05-10-2012 |
20130088252 | METHOD FOR DIAGNOSIS OF CONTACTS OF A PHOTOVOLTAIC SYSTEM AND APPARATUS - A method for monitoring of contacts of a photovoltaic system includes injection of a test signal having a plurality of frequencies, into the photovoltaic system, and determining a generator impedance of the photovoltaic system by evaluating a response signal associated with the test signal. The method further includes monitoring of contacts of the photovoltaic system independently of operating states of the photovoltaic system by modelling of an alternating-current response of the photovoltaic system based on the determined generator impedance, wherein the modelling is specific to at least two different operating states of the photovoltaic system. | 04-11-2013 |
20130121029 | Connecting an Inverter in a Solar Power Plant with Shifted Potential Center Point - The invention relates to a process of connecting an AC output of a transformerless inverter of a solar power plant to an internal AC power grid at an input side of a galvanic isolation, while an offset voltage for shifting a potential center point of a photovoltaic generator connected to the inverter is applied. The process includes: (i) synchronizing the inverter with the power grid; (ii) essentially matching a potential center point of the current-carrying lines of the AC output and a potential center point of the power grid, while only one of the potential center points of the current-carrying lines and the power grid is yet shifted by the offset voltage; and (iii) galvanically connecting all current-carrying lines of the AC output with the power grid only after the steps of synchronizing and essentially matching. | 05-16-2013 |
20140035711 | Magnetically Biased AC Inductor with Commutator - An AC inductor includes a core, at least one permanent magnet for magnetically biasing the core, an inductor winding on the core, and a circuitry which guides an alternating current which flows through the AC inductor in such a way through the inductor winding that, during each half-wave of the alternating current, the alternating current generates a magnetization of the core which is opposite to the magnetization by the permanent magnet. This circuitry includes a commutator which guides the alternating current flowing between two contacts of the AC inductor through the same part of the inductor winding with a same flow direction during each of the half-wave of the alternating current. | 02-06-2014 |
20140119072 | Method and System for Detecting an Arc Fault in a Photovoltaic Power System - A method for detecting an arc fault in a photovoltaic power circuit includes operating a photovoltaic generator at a first working point. A first signal related to a DC-current and/or a DC-voltage in the power circuit is determined. The first signal is analyzed and it is determined whether the signal indicates the presence of an electric arc in the power circuit. If so, the photovoltaic generator is operated at a second working point and a second signal related to the DC-current and/or the DC-voltage is determined. The first and second signals are then compared; and the occurrence of an arc fault in the power circuit is selectively signaled based on the comparison. | 05-01-2014 |
20140321166 | CONNECTING AN INVERTER IN A SOLAR POWER PLANT WITH SHIFTED POTENTIAL CENTER POINT - The invention relates to a process of connecting an AC output of a transformerless inverter of a solar power plant to an internal AC power grid at an input side of a galvanic isolation, while an offset voltage for shifting a potential center point of a photovoltaic generator connected to the inverter is applied. The process includes: (i) synchronizing the inverter with the power grid; (ii) essentially matching a potential center point of the current-carrying lines of the AC output and a potential center point of the power grid, while only one of the potential center points of the current-carrying lines and the power grid is yet shifted by the offset voltage; and (iii) galvanically connecting all current-carrying lines of the AC output with the power grid only after the steps of synchronizing and essentially matching. | 10-30-2014 |