Woodward 5464-033模块备件

Woodward 5464-033

控制通信
两个Modbus端口，用作控制接口。协议可以是
ASCII或RTU，通信可以是RS-232、RS-422或RS-485。
一个计算机（PC）端口，用于程序配置存储。
505E功能的概述如图1-1所示。使用此框图
以将控制功能与所需的现场特定应用程序相匹配。
图1-1a。505E功能概述（注释）
505E数字调速器手册85018V1
6伍德沃德
图1-1b。505E功能概述
手动85018V1 505E数字调速器
伍德沃德7
图1-1c。505E功能概述
505E数字调速器手册85018V1
8伍德沃德
控制概述
505E数字调速器设计用于控制提取、提取和过滤/
或进入蒸汽涡轮机。这些涡轮机之间的差异
是涡轮机允许低压蒸汽的能力
以进入和/或退出涡轮机。抽汽涡轮机
允许低压（抽汽）蒸汽仅从汽轮机中排出，并具有：
抽汽集管/管线中的止回阀，防止蒸汽进入
涡轮机。进气涡轮机（也称为进气）将允许过量的集管
蒸汽通过低压入口进入汽轮机。一
抽汽/进气涡轮机将允许低压集管蒸汽进入或排出
涡轮机的运行取决于系统压力。具有进气能力的涡轮机
将在低压管路中配备截止阀或跳闸和节流阀，以防止
当机组跳闸时，防止蒸汽进入汽轮机。所用涡轮机的类型
将取决于系统要求，必须由涡轮机设计
制造商执行所需的功能。
505E有两个独立的控制通道，即spe

Woodward 5464-033

Woodward 5464-033

auxiliary controllers. The outputs of these two controllers are low-signal-selected (LSS) to provide to speed/load demand signal to the ratio/limiter. In addition to these channels, the speed/ load controller can be manipulated by another controller, the cascade controller. The cascade controller is ‘cascaded’ into the speed controller, whereby the speed controller setpoint is changed directly by the cascade controller output. The auxiliary controller can act as either a control channel or as a limiting channel. All three of these PID controllers have the option of utilizing an analog input signal to remotely position their setpoints. Additional features of the 505E include frequency control, isochronous loadsharing, critical speed avoidance, idle/rated control, and an automatic start sequence. There are two serial communications ports which can be used to monitor and control the turbine using Modbus protocol. Extraction Turbines The 505E control can be configured to operate single automatic extraction turbines by controlling the interaction of the governor (HP or high pressure) valve and the extraction (LP or low pressure) valve. (The 505E can also operate the governor valve and the first extraction valve of multiple extraction turbines). Single automatic extraction turbines have a high pressure stage and a low pressure stage, each controlled by a valve. Steam enters the turbine through the HP valve (see Figure 1-2). At the downstream end of the HP turbine stage and before the LP valve, steam can be extracted. The LP valve controls the entry of steam into the LP turbine stage, and the diverting of steam through the extraction line. As the LP valve is opened, more steam enters the LP stage and less is extracted. In most cases, the operator of an extraction turbine needs to maintain both turbine speed/ load and extraction pressure/flow at constant levels. Changing the position of either the HP valve or the LP valve affects both turbine speed/load and extraction. If either the load on the turbine or the extraction demand changes, both the HP valve position and the LP valve position must be changed to maintain speed/load and extraction. The movement of both valves is automatically calculated by the 505E’s ratioing logic based on the turbine performance parameters to minimize valve/process interaction. Manual 85018V1 505E Digital Governor Woodward 9 Figure 1-2. Typical Extraction and/or Admission Steam Turbine Admission Turbines The 505E control can be configured to operate single automatic admission turbines by controlling the interaction of the governor (HP or high pressure) valve and the extraction (LP or low pressure) valve. Single automatic admission turbines have a high pressure stage and a low pressure stage, each controlled by a valve. Steam enters the turbine through the HP valve (see Figure 1-3) and at the downstream end of the HP turbine stage, before the LP valve. The LP valve controls the entry of steam into the LP turbine stage and through the admission line. As the LP valve is opened, more steam enters the LP stage.