Abstract:
A method and an apparatus for setting up synchronization, with a power grid, of an inverter having a photovoltaic generator as a primary energy source is disclosed. The inverter is supplied with the energy from an additional energy source connected in parallel with input terminals of the inverter, wherein the additional energy source is a DC energy source operated independent from the primary energy source. The frequency, phase relationship and output voltage of the inverter supplied from the additional DC energy source are matched to the frequency, phase relationship and output voltage of the power grid, whereafter the primary energy source is connected to the inverter. With this method, an inverter dimensioned for a permissible open-circuit voltage can also be used under operating conditions, without requiring modifications of the circuitry of the primary energy source.
Abstract:
In a method for forecasting shadowing of a photovoltaic (PV) system due to cloud formation or movement, part of the firmament is imaged with fisheye optics onto the input optics of a digital camera. Pixel groups associated with luminous intensity ranges are formed. The spatial arrangement of the groups is analyzed to forecast shadowing of a photovoltaic system. A line extending from the PV system to the sun is formed and is continuously tracked. A reference line located inside a region around the line is formed. Passage of clouds across a reference line is analyzed. The result of the analysis is used to increase the electric power from the PV system to a minimum value through supply of additional backup energy or to reduce the electric power consumption by disconnecting users to ensure that key users do not experience a drop in supplied power below a minimum value.
Abstract:
A photovoltaic system includes a plurality of photovoltaic modules and a DC motor connected to a three-phase generator driven by a shaft. The three-phase generator is connected to a power mains. The electric power supplied to the DC motor by the plurality of photovoltaic modules is repeatedly measured and adjusted, by changing an external excitation current of the DC motor, to the peak power attainable at the current ambient temperature and the current incident solar radiation intensity. The peak power is preferably determined by incrementally changing the excitation current in predetermined time intervals, until the supplied electric power produces a power level which can be regarded as the peak power.
Abstract:
The invention relates to a valve device, preferably for a line device or connecting device. Said valve device comprises a valve body that can be transferred from an open position to a closed position. Said valve body comprises movable sectored devices having sealing edges or sealing surfaces via which, in a closed position, a sealing contact of the sectored device to adjoining sealing edges or sealing surfaces can be established. The sectored devices can at least be in sections moved away in the radial direction from the centre axis when the valve body is transferred to the open position and release a flow area.
Abstract:
The invention relates to an interchangeable fitting with a fitting housing (12), a removable measurement probe (14) which is movably guided axially in the housing (12) for insertion into a container, a shut-off element (16) which closes the fitting (10) relative to the interior of the container, and a guide means (22) which can be guided to move axially in the housing (12) for holding and guiding the measurement probe (14) in the fitting housing (12) between a measurement position in which the measurement probe (14) has been inserted into the container, and a stand-by position in which the measurement probe (14) is located within the fitting housing (10), the measurement probe (14) comprising a measurement probe body (15) and a sensor (26), the measurement probe (14) being fixed with its measurement probe body (15) on the end face (23) of the guide means (22), and the sensor (26) being mounted on the free side of the measurement probe body (15) which points in the direction to the container and the cross section of the guide means (22) being smaller than the cross section of the measurement probe (14).
Abstract:
A system for feeding direct current into an alternating current network includes a plurality of active inverters with each of the active inverters having an optimum input power and being connected at a respective input side to at least one direct current generator of fluctuating output power. A switching device is included for the one or more direct current generators from a first active inverter to a second active inverter, or vice-versa, for effecting a switchover operation, with a control device initiating the switchover operation upon fulfillment of a condition; the control device including a device for determining when the condictionis fulfilled.
Abstract:
A liquid-proof plug connector, for example for two cables to be connected, is described, which is provided with a plug and a coupling to which the two cables can be connected. The plug connector is furthermore provided with a plug housing and a coupling housing in which the plug and the coupling are housed, and with a locking ring by means of which the plug housing and the coupling housing can be screwed together. The plug housing and the coupling housing have an overlapping area in the screwed-together state, in which a seal between the two housings is arranged.
Abstract:
There is disclosed a catalytic waste gas converter for internal combustion engines of various types in which there is used as carrier for the catalyst a carrier matrix made of a steel screen arranged in a housing holder. There are employed special flow guides made of spirally wound steel matrices for the various flow through possibilities favorable to conversion of the waste gas to be purified.
Abstract:
There is disclosed a catalytic waste gas converter for internal combustion engines of various types in which there is used as carrier for the catalyst a carrier matrix made of a steel screen arranged in a housing holder. There are employed special flow guides made of spirally wound steel matrices for the various flow through possibilities favorable to conversion of the waste gas to be purified.
Abstract:
The invention relates to a holding system (1) for mounting a photovoltaic module (6) to a base (8) by means of ground supports (2, 2a, 44, 44a) which comprise a bearing head (4, 4a, 50, 50a), a ground support body (22) and a bearing surface (28, 48) on the bottom side which counteracts a penetration of the ground supports into the base (8), wherein the ground supports (2, 2a, 46, 46a) comprise on their head side a bearing plate (14, 14′, 14a, 14a′, 54, 54′, 54a, 54a′) that is disposed at a slanted angle (α) in relation to the base (8), and wherein the ground supports (2, 2a, 46, 46a) are provided and prepared such that, in the mounted state, the bearing plates (14, 14′, 14a, 14a′, 54, 54′, 54a, 54a′) of a ground support pair (2, 2a, 46, 46a) are spaced apart from each other vertically in relation to the base (8) and from each other horizontally in adjustment to the photovoltaic module (6) and that they are aligned with each other at least in essence.