Patent GB-191415027-A (GB)
Title: An Improved Method and Apparatus for Regulating Multicylinder Steam Engines or Coupled Steam Turbines.
Inventor: SCHOU ERIK
IPC: G05D13/00
Filed: 1914-06-23
Granted: 1915-05-13
Abstract: 15,027. Schou, E. June 23. Regulating combined turbine-power and heating plant. Relates to the method of regulating multicylinder steam - engines or coupled steam turbines, from which some of the steam is taken for heating or other purposes, of the kind in which the regulation of the flow of steam through the engine is effected by means of a speed governor and a pressure regulator actuated by the pressure of the steam in the receiver from which steam for heating &c. is taken, the governor and regulator being so connected to one another that either can move wholly independently of the other. According to the invention, the governor and regulator so control the supply of steam to the engine that the admission of steam to all of the various sections of the engine is simultaneously cut off if the speed governor alone occupies the position corresponding to the maximum number of revolutions of the engine independently of the position of the pressure regulator. Such an arrangement prevents racing of the engine when steam is admitted directly from the generators to the receiver to supplement that withdrawn for heating or like purposes. As shown in Figs. 2 and 3, applied to a compound steam-engine in which the valve-gear of the low-pressure cylinder is actuated both by the centrifugal governor V and the pressure regulator T and the valve-gear of the high-pressure cylinder H is actuated solely by the speed governor, the shaft q of the supply valve of the low-pressure cylinder is operated by a rod p in connexion with the linkage system n, c, k, m, the upper end j of the link m being actuated by the speed governor, and in connexion with the links b, d, the upper-end of the link d being actuated by the pressure regulator. The point a is a fixed pivot, and the linkage system is so designed that the governor and regulator affect the position of the rod p independently of each other and the rod p has a definite position in which it cuts off the steam supply wholly independently of the position of the pressure regulator when the speed governor assumes the position corresponding to the maximum number of revolutions. In the arrangement shown, the links c, k, m are of equal length. In order to ensure that the pressure in the receiver remains constant whatever the load on the engine, it is essential that the admission of steam to the low-pressure cylinder should be comparatively high when the speed governor is admitting a maximum amount of steam to the highpressure cylinder. This is effected by interposing the linkage system e, y, g, x of which the pivots z, f are fixed, between the speed governor and the upper end j of the link m, so that the movement of the governor is ' concentrated ' in the neighbourhood of its highest positions, i.e. in this neighbourhood movement of the governor transmits only a relatively small movement to the point j, and consequently to the supply valve of the low-pressure cylinder. The speed governor alone may act on the lowpressure cylinder, and both the governor and regulator on the high-pressure cylinder. The control arrangements may be employed for twocylinder high-pressure engines as shown in Fig. 6, one of the cylinders of which works with condensation, and the other with a certain backpressure which provides the steam for heating or like purposes. In this case, both cylinders are regulated jointly by the speed governor and pressure regulator, and the connexion to the speed governor in each case is such that the admission to both cylinders is zero when the speed governor occupies its highest positions, but the linkage connexions to the pressure governor are such that the admission of steam to the cylinder working with condensation will be decreased and the admission to the other increased when the pressure regulator falls owing to decreased pressure within the receiver. Linkage systems are interposed between the pressure regulator and supply valve so that the movement of the regulator is concentrated in the neighbourhood of the lowest position of the regulator for the cylinder working with backpressure, and for the other cylinder in the neighbourhood of the highest position of the regulator. The invention is applicable to compound steam turbines from between the stages of which steam is taken, and to coupled highpressure steam turbines, one of which works with condensation and the other with backpressure used for heating &c.