A control gate for a channel or pond adapted to be installed across a channel for liquids. The control gate includes: at least two panels hingedly connected together, the panels having opposing sides in sealing engagement with side walls of the channel, a lowermost panel being in sealing engagement with the floor of the channel. The panels are substantially vertically aligned in a fully closed position of the control gate. At least one first lifting element is connected to the top of an uppermost panel and is adapted to lower and raise the uppermost panel relative to its hinged connection in a concertina manner to provide an overshot position for the control gate. At least one second lifting element is connected to the bottom of the lowermost panel to raise and lower the lowermost panel from the floor of the channel to provide an undershot position for the control gate.

A control gate for a channel or pond adapted to be installed across a channel for liquids. The control gate includes: at least two panels hingedly connected together, the panels having opposing sides in sealing engagement with side walls of the channel, a lowermost panel being in sealing engagement with the floor of the channel. The panels are substantially vertically aligned in a fully closed position of the control gate. At least one first lifting element is connected to the top of an uppermost panel and is adapted to lower and raise the uppermost panel relative to its hinged connection in a concertina manner to provide an overshot position for the control gate. At least one second lifting element is connected to the bottom of the lowermost panel to raise and lower the lowermost panel from the floor of the channel to provide an undershot position for the control gate.

An inflatable flood barrier includes a board having a side plate and a peripheral plate attached to the side plate. The board being provided with a charging port, the peripheral plate has rounded corners, and the side plate has corner portions. The rounded corners and the corner portions are positionally corresponding. The corner portion has guiding grooves. A flexible seal embraces at least a part of the peripheral plate and has an internal channel, a gas inlet and a gas discharging port. When the flexible seal is inflated at the internal channel, a watertight combination between the inflatable flood barrier and a contacting surface of a gate it protects is achieved. The inflatable flood barrier is structurally simple, watertight, convenient to use and store, apparently pleasing, and functionally versatile.

The invention relates to a method for controlling a water sluice gate drive for a water sluice gate, in particular for a roller sluice gate, preferably in a hydroelectric power plant, wherein the drive has an electric machine, in particular has an asynchronous machine, in particular an asynchronous motor/generator. According to the invention, it is provided that the electric machine, in particular an asynchronous machine, has a fan brake, wherein the method comprises the steps of: disengagement of the fan brake in the case that an insufficient power supply is indicated, self-actuated operation of the electric machine, in particular an asynchronous machine, wherein the electric machine, in particular an asynchronous machine, is operated in generative island operation, in which a rotating field is generated in a self-actuating manner.

The invention relates to a method for controlling a water sluice gate drive for a water sluice gate, in particular for a roller sluice gate, preferably in a hydroelectric power plant, wherein the drive has an electric machine, in particular has an asynchronous machine, in particular an asynchronous motor/generator. According to the invention, it is provided that the electric machine, in particular an asynchronous machine, has a fan brake, wherein the method comprises the steps of: disengagement of the fan brake in the case that an insufficient power supply is indicated, self-actuated operation of the electric machine, in particular an asynchronous machine, wherein the electric machine, in particular an asynchronous machine, is operated in generative island operation, in which a rotating field is generated in a self-actuating manner.

A control gate for a channel or pond adapted to be installed across a channel for liquids. The control gate includes: at least two panels hingedly connected together, the panels having opposing sides in sealing engagement with side walls of the channel, a lowermost panel being in sealing engagement with the floor of the channel. The panels are substantially vertically aligned in a fully closed position of the control gate. At least one first lifting element is connected to the top of an uppermost panel and is adapted to lower and raise the uppermost panel relative to its hinged connection in a concertina manner to provide an overshot position for the control gate. At least one second lifting element is connected to the bottom of the lowermost panel to raise and lower the lowermost panel from the floor of the channel to provide an undershot position for the control gate.

A control gate for a channel or pond adapted to be installed across a channel for liquids. The control gate includes: at least two panels hingedly connected together, the panels having opposing sides in sealing engagement with side walls of the channel, a lowermost panel being in sealing engagement with the floor of the channel. The panels are substantially vertically aligned in a fully closed position of the control gate. At least one first lifting element is connected to the top of an uppermost panel and is adapted to lower and raise the uppermost panel relative to its hinged connection in a concertina manner to provide an overshot position for the control gate. At least one second lifting element is connected to the bottom of the lowermost panel to raise and lower the lowermost panel from the floor of the channel to provide an undershot position for the control gate.