CONTROL CONCEPT FOR CLOSED LOOP BRAYTON CYCLE

• US 20160319749A1
• Filed: 04/26/2016
• Published: 11/03/2016
• Est. Priority Date: 04/29/2015
• Status: Active Grant

• Current Assignee: General Electric Technology GmbH (GE Aerospace)
• Original Assignee: Alstom Technology Ltd. (Alstom SA)
• Inventors: LAFFONT, Patrick
• Granted Patent: US 10,001,065 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: F01D 17/145 by means of valves, e.g. for steam turbines valves in general F16K
• CPC Class Codes: F01D 17/148 by means of rotatable members, e.g. butterfly valves
• CPC Class Codes: F01D 5/02 Blade-carrying members, e.g. rotors rotors of non-bladed type F01D1/34; stators F01D9/00 ; selecting particular materials F01D5/28
• CPC Class Codes: F01K 5/00 Plants characterised by use of means for storing steam in an alkali to increase steam pressure, e.g. of Honigmann or Koenemann type
• CPC Class Codes: F02C 1/105 construction; details
• CPC Class Codes: F02C 9/16 Control of working fluid flow F02C9/48 takes precedence; control of air-intake flow F02C7/057
• CPC Class Codes: F02C 9/20 by throttling; by adjusting vanes
• CPC Class Codes: F02G 2250/03 Brayton cycles
• CPC Class Codes: F04D 29/321 for axial flow compressors
• CPC Class Codes: F05D 2260/20 Heat transfer, e.g. cooling
• CPC Class Codes: F05D 2260/606 Bypassing the fluid
• CPC Class Codes: F05D 2270/021 to prevent overspeed
• CPC Class Codes: F05D 2270/091 in particular sudden load loss
• CPC Class Codes: F05D 2270/304 Spool rotational speed
• CPC Class Codes: F05D 2270/3061 of the working fluid

Abstract

An improved closed loop Brayton cycle for a power plant is provided that includes a heater, at least one turbine, a recuperator, at least one cooler, at least one compressor, a bypass line and a flap valve arrangement in a closed circuit in which working fluid is circulated to produce electricity via a generator. Depending upon the requirement, such as, in case of gird load disconnection, speed of a shaft-line to which the turbine, the compressor and the generator are configured is also required to be reduced without any impact on the pressure drop in the cycle. For that the non-tight flap valve arrangement is configured on each conduit between the heater and the at least one turbine in a closest possible proximity to each turbine inlet.

Claims

1. An improved closed loop Brayton cycle for a power plant, the cycle having a working fluid flowing therein for operation, the cycle, comprising:

a heater having an inlet and an outlet, the heater adapted to supply heat to the working fluid flowing in the cycle;

at least one turbine operable on the expansion of the compressed heated working fluid, and drivingly connected to a variable load via a shaft-line, each of the at least one turbine having an inlet and an outlet, wherein each inlet of the at least one turbine is connected to the outlet of the heater via a conduit;

a recuperator connected to the turbine via the outlet to receive expanded working fluid to cool thereto, and connected to the heater via the inlet of the heater;

at least one cooler connected to recuperator to further cool the working fluid;

at least one compressor on the shaft-line and driven by the at least one turbine, the compressor connected to the at least one cooler to receive and compress the working fluid to transfer to the recuperator to be heated by the expanded working fluid from the turbine and supply to the heater; and

a non-tight flap valve arrangement configured on each conduit between the heater and the at least one turbine in a closest possible proximity to each turbine inlet to manage the mass flow of working fluid through the non-tight flap valve arrangement to control the shaft-line speed when the variable load is disconnected from the grid.

2. The cycle as claimed in claim 1, wherein the conduit comprises a recess where the non-tight flap valve arrangement is housed in the recess to substantially minimize pressure drop in the cycle upon normal operation.

3. The cycle as claimed in claim 2, wherein the non-tight flap valve arrangement comprises:

a flap member; and

an attaching segment having a flap axle to pivotally attach the flap member, the attaching segment enables the attachment of the non-tight flap valve arrangement on the conduit to be housed at the recess,

wherein the flap member at an open position completely covers the recess and allows the working fluid to fully flow from the conduit to the at least one turbine, and

wherein the flap member at closed position is non-tight, which allows the conduit to be partially closed to enable the adjustment of the mass flow of working fluid to admit from the conduit to the at least one turbine.

4. The cycle as claimed in claim 3, wherein the flap member is shaped to correspond the shape of the conduit to substantially minimize pressure drop in the cycle upon normal operation.

5. The cycle as claimed in claim 3, wherein the non-tight flap valve arrangement is self-closing non-tight flap valve arrangement that are adapted to be partially closed in responsive to disconnection of the variable load from the grid.

6. The cycle as claimed in claim 5, wherein the self-closing non-tight flap valve arrangement is controlled via an electronic module.

7. The cycle as claimed in claim 3, further comprising a covering arrangement adapted to cover the recess and the non-tight flap valve arrangement and block exiting of the working fluid from the cycle.

8. The cycle as claimed in claim 3, wherein the non-tight flap valve arrangement in closed position is non-tight, in which the flap member is configured to pivotally swing along the flap axel that enables the flap member to be partially opened to allow the working fluid with adjusted mass flow to pass from the conduit.