| 摘要 |
<p>The present invention relates to method of controlling the flow of working medium through an expansion device (1) for use in a closed heating system. In addition to the expansion device (1), the system also includes a condenser (13), a pump (16) and a boiler (10), wherein the expansion device consists in a helical screw rotor expander (1) that has an inlet port (2) an inlet line (11) connected thereto, and an outlet port (3). The expansion device drives an energy producing device (G), for instance a generator. The method is characterized by providing the helical screw rotor expander (1) with an intermediate pressure port (4) between the inlet port (2) ad the outlet port (3), by connecting the intermediate pressure port (4) with the inlet line (11) via a branch line (18) between the intermediate pressure port (4)and a branching point (21) in the inlet line, by including a valve (19) in the branch line (18), and by controlling the flow of working medium through the valve (19) to the intermediate pressure port (4) as a function of a state parameter. The invention also relates to an arrangement which is characterized in that includes an intermediate pressure port (4) in the expander (1) between the inlet port (2) and the outlet port (3), in that it further includes a branch line (18) which connects the intermediate pressure port (4) with the inlet line (11) at a branching point (21) and includes a valve (19) in the branch line (18).</p> |
