Abstract:
A photovoltaic system having a plurality of photovoltaic modules producing electric energy and method for operating such photovoltaic system are disclosed. With the method, the photovoltaic modules are connected to a first DC motor having a motor shaft, and a generator shaft of a three-phase generator is coupled to the motor shaft. The three-phase generator can be connected to a power grid. The motor shaft of a second DC motor can be connected to the generator shaft, with only one of the two DC motors being initially driven with the electric energy produced by the photovoltaic modules. The electric energy is subsequently divided among both the first and the second DC motor. This process significantly shortens the startup process of the photovoltaic system compared to conventional systems.
Abstract:
An apparatus and a method for preparing connection of a photovoltaic system (Q1) as a first energy source to a power grid (13) by way of a motor generator set (5, 6, 7) is presented. The DC motor (5) is coupled to a three-phase generator (7) by way of a shaft (6), wherein the three-phase generator (7) can be connected to the power grid (13). It has been observed that connecting this type of apparatus to the small or varying power output of the photovoltaic system (Q1) can be difficult and time-consuming. To enable a clean and quick connection, the DC motor (5) is powered with electric DC current from a second DC current source (Q2), wherein the operation of the three-phase generator (7) is matched to the conditions in the power grid (13) with the help of the second DC current source (Q2), and wherein the photovoltaic system (Q1) is connected to the DC motor (5) and the second DC current source (Q2) is disconnected from the DC motor (5) only after a complete match has been attained. This enables a quick and precise connection of the photovoltaic system (Q1) to the power grid (13) with defined parameters using the three-phase generator (7).
Abstract:
An automatable measuring, cleaning and calibrating device for pH-electrodes or electrodes for measuring redox potentials, specifically in process engineering, having an electrode armature which keeps the measuring electrode in an operating position or in a maintenance position, whereby the electrode is retained in the maintenance position in a rinsing chamber in which a cleaning and calibration procedure can be performed. The device has a pump device to supply cleaning fluid and calibration solutions to the rinsing chamber over a delivery line connecting the pump device and the rinsing chamber. In order to configure the device more compactly, the pump device includes several feeds on its intake side, and a device is furnished to selectively activate a particular feed, and the media (cleaning fluid, calibration solution, etc.) brought selectively over the particular feeds to the pump device reach the rinsing chamber over the common delivery line.
Abstract:
An improved carrier matrix for catalysts is described wherein layers are disposed one on top of the other consisting of highly temperature resistant and non-scaling steel formed into a smooth screen into which closed hollow or open supporting profiles of a larger cross section than the screen are woven in or on at parallel distances. Layers of screens provided with profiles may be combined with layers of flat screens or smooth or corrugated sheet metal. The carrier matrix may be coated with a catalytically active carrier such as gamma-aluminum oxide and then receive a coating of a catalytically active metal whereby the resulting product may be used to treat auto exhaust gases for purification.
Abstract:
A 3D printer and method for increasing the speed of 3D printing, wherein said 3D printer comprises a heating block, a nozzle (1) attached to the heating block, and a hole through the heating block and the centre of the nozzle (1). In said hole there is a heat conductive material (7) attached in at least one place on the inner side wall of the hole for transferring heat (5) from the side wall towards the centre of the hole.
Abstract:
A meter for recording or determining the electrical energy withdrawn from an electrical supply network or supplied to it is provided. The meter including a component for measuring the current supply voltage, and a component for determining the operating mode based on the currently withdrawn or supplied electrical energy, wherein the operating mode can be changed, depending on the measured supply voltage, in such a way that a relatively high supply voltage causes a slower metering process than a comparatively low supply voltage.
Abstract:
A measuring method for determining an output drop of a PV unit is provided. The PV unit is arranged within a photovoltaic system comprising a plurality of electrically parallel-connected PV units. Each PV unit can be removed from the parallel circuit by a switching device. Further, a total current measuring device for measuring the total current through all PV units of the parallel circuit is provided. The defective PV unit is determined in an evaluation unit by the connection and disconnection of a disconnect switch.
Abstract:
An arrangement with a photovoltaic generator is provided that can be connected to the input of a power inverter, the output of which is connected to a supply network. The arrangement further comprises an asynchronous machine parallel to the output of the power inverter, which asynchronous machine is driven by an internal combustion engine.
Abstract:
A measuring method for determining an output drop of a PV unit is provided. The PV unit is arranged within a photovoltaic system comprising a plurality of electrically parallel-connected PV units. Each PV unit can be removed from the parallel circuit by a switching device. Further, a total current measuring device for measuring the total current through all PV units of the parallel circuit is provided. The defective PV unit is determined in an evaluation unit by the connection and disconnection of a disconnect switch.
Abstract:
A photovoltaic system includes an inverter, a photovoltaic generator with a plurality of serially connected photovoltaic modules, said photovoltaic generator connected to the inverter by an electrical supply line, a controllable fuse interconnected in the electrical supply line between the inverter and the photovoltaic generator and having a signal input, and a voltage-dependent resistor connected between the signal input of the controllable fuse and the electrical supply line and generating a control signal which triggers the controllable fuse responsive to the control signal and interrupts the electrical supply line. The controllable fuse can be used to disconnect the electrical connection of the photovoltaic system to the inverter when a switch short-circuiting one or more modules of the photovoltaic generator malfunctions. The arrangement permits operation of photovoltaic system at an operating voltage of close to 1000 V, thereby allowing use of thinner cables.