Translation of "Compressor surge" in German

This leads to neutralizing the problem of compressor surge at high specific braking powers.

In particular the invention seeks to make it possible to avoid compressor surge when a grid fault occurs, in particular a dynamic grid voltage drop, with regard to prevailing grid and system rules.

Actuation of the at least one bypass valve and deactivation of the ignition in the internal combustion engine makes it possible to achieve a prolonged period of time with deactivated ignition without compressor surge occurring.

The critical operating state is reached when the compressor accelerates, in the case of which compressor the surge limit margin is provisionally lowered.

This correction allows precise determination of the operating state and an optimally efficient operation of the compressor below the surge limit.

If the surge limit is exceeded, that results in a stall at the compressor vanes of the turbocharger and so-called compressor surge occurs, which, as a further consequence, can lead to an unstable operating condition with respect to the internal combustion engine.

In order to prevent the undesired operating state of the “pumping” of the compressor, the anti-surge valve should be opened rapidly, so that the output of the compressor can be reduced at the outlet.

In addition, the VIGVs cannot be opened indefinitely because of the compressor surge limit and the required safety margin from the surge limit, or limits of other components.

Here, a turbine operating parameter can characterize abnormal operating conditions, such as the starting of the turbine, the re-ignition of the turbine, water ingestion, a compressor surge and/or an extinction of the combustion.

Based on this, various—sometimes abnormal—operating conditions may be detected, including startup of the aircraft engine, rapid re-ignition of the aircraft engine, water ingestion, a compressor surge in the fuel feeding system, or an extinction of the burner flame.

If stall occurs, i.e. in the unstable operating range of the compressor beyond the surge limit with correspondingly increased blade loading, the blades encounter uncontrolled vibration and may be damaged or destroyed.

The increased air quantity which can pass through the internal combustion engine during two-stroke braking operation also leads to neutralizing the problem of compressor surge at high specific braking powers.

As compared with the characteristic line 41, the characteristic line 40 for two-stroke braking is at a markedly greater distance from the surge limit 30, so that, in two-stroke braking, the risk of compressor surge is considerably reduced.

The fictitious surge limit line can be reproduced within the surge limit control, and a control line according to the “fictitious” surge limit line can be preset for the protection system of the compressor (surge limit control).

To make it possible to ensure this, a control line is positioned to the right of the surge limit with a sufficient safety margin such that the surge limiter can always operate the compressor outside the surge limit range even under extreme operating conditions.

Such compressor surging has a disadvantageous effect on the efficiency of the turbomachine.

This compressor surging should be avoided because the pressure fluctuations that arise lead to intense mechanical loading.

The resulting rapid and still moderate response on the part of the blow-off valve makes the method appropriate for even high-demand regulating procedures intended to protect the compressor from surging.

The functional values of this curve are the values at which it is still just possible to prevent the compressor from surging in accordance with the actual position and actual speed of the operating point in the performance field.

As the operating point arrives at the curve representing this function, it will still be just possible to prevent compressor 1 from surging.

Although this method has been proven in practice, especially in relation to protecting the compressor from surging, it does have drawbacks.

These two variables can be looked on as actual and set-point values to a conventional surge limit control which protects the compressor against surging.

It is additionally known from experiments on the test floor which inflow angle leads to stall and thus to compressor surging, in such a way that the surge limit is securely recorded in the map.

This is also done when the gas turbine is retarded from a higher power level to prevent the high-pressure compressor from surging upon reaching the surge limit.

In the case of compressors in turbomachines, when operating the compressor outside a design point of the rotor blades, a so-called compressor surging may occur on a regular basis, in which the pressure in the compressor drops from the rear to the front due to a flow separation on the rotor blades and a backflow is formed.

On these turboprop engines, bleed air 41 is in certain operating ranges, in particular during ground idle operation, discharged from the engine nacelle 3 through the bleed air line 25 and the bleed air valve 26 to prevent the high-pressure compressor 5 from surging upon reaching the surge limit.

As a result, the surge limit regulator intervenes markedly more strongly in the case of a process disturbance and it protects the compressor from surging considerably better.