Category: Woodward

Common Problems with Hydraulic Actuators in Heavy Duty Gas Turbines

›Hydraulic fluid viscosity dependent on ambient temperatures

– leads to slower response times in cold temperatures

– resulting in failed starts

›Fluid varnishing can lead to clogged servovalve passages resulting in failed starts or stops

›Potential of high pressure hydraulic leaks pose safety risks

›Premature seal failure – noise on hydraulic control circuits can lead to premature

wear on hydraulic and gas seals

›No actuator/valve data to predict failure in advance of outages

Benefits of Electric

›Elimination of hydraulic fluid and associated problems with contamination,

cold weather and leakage

›Higher reliability design inherent to electric actuation significantly increase maintenance intervals

› Improved control response and precision

›OEM Qualified and included with the majority of new Gas Turbines

›Compliant with NERC standards for cold weather preparedness

›Service Tool provides enhanced diagnostics for plant personnel and early indication

of performance issues at the DCS operator terminal

Heavy Duty Gas Turbines have increasingly been dispatched to support

the grid during renewable energy transition. These market conditions

drive fleet owners to operate their assets as peakers, creating the need

for frequent starts. Start-up reliability has become a key success factor

for these units.

Common Problems with Hydraulic Actuators in Heavy Duty Gas Turbines

›Hydraulic fluid viscosity dependent on ambient temperatures

– leads to slower response times in cold temperatures

– resulting in failed starts

›Fluid varnishing can lead to clogged servovalve passages resulting in failed starts or stops

›Potential of high pressure hydraulic leaks pose safety risks

›Premature seal failure – noise on hydraulic control circuits can lead to premature

wear on hydraulic and gas seals

›No actuator/valve data to predict failure in advance of outages

Benefits of Electric

›Elimination of hydraulic fluid and associated problems with contamination,

cold weather and leakage

›Higher reliability design inherent to electric actuation significantly increase maintenance intervals

› Improved control response and precision

›OEM Qualified and included with the majority of new Gas Turbines

›Compliant with NERC standards for cold weather preparedness

›Service Tool provides enhanced diagnostics for plant personnel and early indication

of performance issues at the DCS operator terminal

Rugged and precise fuel control and shutoff valves for large, heavy-duty gas

turbines with single or multiple combustion manifold systems.

Available in electric or hydraulic models.

Features & Benefits

• Ultra-low pressure drop valve body design reduces gas compression operating costs

• Electric actuator options eliminate the need for high-pressure hydraulic fluid,

which improves safety and eliminates downtime caused by hydraulic fluid varnishing clogging servo

valves

• Onboard diagnostics to provide advance notification of potential operating problems

Product Variants

• LESV – Large Electric SonicFlo Valve

• Electric Rotary Pressure and Flow Control Valve

• Hydraulic Gas Control Valve

• Hydraulic Stop/Ratio Valve

The 3103 gas valve is a rotary sleeve-and-shoe type-throttling valve.

Valve position feedback to the actuator driver is accomplished using a high accuracy resolver.

The EM35MR actuator is designed for use with the DVP (Digital Valve Positioner).

Features and Benefits

• Design of the valve is to be corrosion resistant and self-cleaning, allowing it to

operate in sour gas environments (high sulfur content gas) that can cause problems for other valves

• The EM35MR actuator is all electric, reducing hydraulic contamination and maintenance problems

• The DVP uses the latest in Woodward control architecture, robust controller to provide high-speed

precise valve control

Product Variants

3103 EM35MR

• Conduit Entry

• 2.0 Inch RF ANSI Flange

• 24 VDC Input Voltage

• Standard Inlet Pressure and Enhanced Inlet Pressure Options

Product Specifications 3103 EM35MR

Maximum Gas Supply Pressure

• 720 psia (4964 kPa) – Standard Inlet Pressure (CSA and CE)

• 900 psia (6205 kPa) – Standard Inlet Pressure (CSA)

• 900 psia (6205 kPa) – Enhanced Inlet Pressure (CSA and CE)

Fuel Temperature

• -40 to +300 degrees Fahrenheit (-40 to +149 degrees Celsius)

Ambient Temperature

• -40 to +200 degrees Fahrenheit (-40 to +93 degrees Celsius)

The 2301E has four modes of operation:

Speed Control

Provides a wide range of dynamic flexibility. Can be used for pumps or compressors.

Remote 4-20 mA speed reference via configurable analogue input.

Asynchronous Load Sharing

Compatible with most existing analogue load sharing speed control systems.

Now with soft loading and unloading capabilities.

Dropped Base Load

Adjustable load control using discrete lift contacts.

Constant Speed Base Load

Provides constant load level operation against the mains bus. 

Load settings can be fixed or changed using discrete raise and lower inputs or a remote 4-20 mA input.

The Woodward 2301E provides load sharing and speed control for generators driven by diesel or gas

engines.

With the flexible configuration software in the 2301E hardware,

Application variations can now be selected using an external computer (PC).

Applications can be changed to accommodate engine speed ranges, gear tooth counts,

and forward and reverse selections with a simple software setup.

The 2301E is capable of communicating using the Modbus® * RTU protocol,

operating as a Modbus slave device via an RS-422 driver.

The 2301E includes

 1 load cell circuit

 1 actuator driver, 4-20 mA, 0-20 mA, 0-200 mA or PWM

 1 MPU speed sensor

 1 configurable analogue output

 2 configurable analogue inputs

 8 discrete (switching) inputs

 4 discrete (relay driver) outputs

The 2301E has an operating temperature range of -40 to +70 °C (-40 to +158 °F).

The Woodward 2301E provides load sharing and speed control for generators driven by diesel or gas

engines.

With the flexible configuration software in the 2301E hardware,

Application variations can now be selected using an external computer (PC).

Applications can be changed to accommodate engine speed ranges, gear tooth counts,

and forward and reverse selections with a simple software setup.

The 2301E is capable of communicating using the Modbus® * RTU protocol,

operating as a Modbus slave device via an RS-422 driver.

Control specifications

Inputs

– Power Supply Low voltage models 18-32 VDC High voltage models 88-264 VAC and 90-150 VDC

– Speed: 2 passive MPUS or active proximity probes (0.5 – 32000 Hz)

– Discrete Inputs 19 configurable contact inputs (16 additional contact inputs can be added using LinkNet

HT)

– Analogue Inputs 8 configurable 4-20 mA (16 inputs or 8 RTD inputs can be added using LinkNet HT)

Outputs

– Valve/actuator driver: 2 actuator outputs, 4-20 mA or 20-200 mA

– Discrete Outputs:

– 7 configurable relay outputs (16 discrete outputs can be added using the LinkNet HT module)

– Analogue Outputs 6 programmable 4-20 mA outputs (4 inputs can be added using the LinkNet HT

module)

Communications

– Ethernet 3 ports (Modbus TCP or OPC)

– Serial 1 port (ASCII or RTU, RS-232 or RS-485)

– CAN: 4 ports, supports LinkNet HT, VariStroke, and power management devices

Operating Conditions

– Ambient air temperature: -25 to +65C

– Humidity Lloyd’s ENV2 Test #1

– Dry heat Lloyd’s ENV3

– Salt Spray: US MIL-STD-810. Method 509.2 proc. 1

– Shock: US MIL-STD-810C, Method 516.2-1 proc. 1B

– Vibration Lloyd’s ENV2 Test #1

– Resistance to particulate contamination IEC 60664-1 Class 2

– IEC 60068-2-60 part 2.60 methods 1 and 4

– Resistance to gaseous contamination: coating is resistant to NO2. CO2. SO2 and H2S.

– Battelle Laboratories Class III (IEC 60721-3-3 Categories 3C1 and 3C2)

Control specifications

Inputs

– Power Supply Low voltage models 18-32 VDC High voltage models 88-264 VAC and 90-150 VDC

– Speed: 2 passive MPUS or active proximity probes (0.5 – 32000 Hz)

– Discrete Inputs 19 configurable contact inputs (16 additional contact inputs can be added using LinkNet

HT)

– Analogue Inputs 8 configurable 4-20 mA (16 inputs or 8 RTD inputs can be added using LinkNet HT)

Outputs

– Valve/actuator driver: 2 actuator outputs, 4-20 mA or 20-200 mA

– Discrete Outputs:

– 7 configurable relay outputs (16 discrete outputs can be added using the LinkNet HT module)

– Analogue Outputs 6 programmable 4-20 mA outputs (4 inputs can be added using the LinkNet HT

module)

Communications

– Ethernet 3 ports (Modbus TCP or OPC)

– Serial 1 port (ASCII or RTU, RS-232 or RS-485)

– CAN: 4 ports, supports LinkNet HT, VariStroke, and power management devices

Operating Conditions

– Ambient air temperature: -25 to +65C

– Humidity Lloyd’s ENV2 Test #1

– Dry heat Lloyd’s ENV3

– Salt Spray: US MIL-STD-810. Method 509.2 proc. 1

– Shock: US MIL-STD-810C, Method 516.2-1 proc. 1B

– Vibration Lloyd’s ENV2 Test #1

– Resistance to particulate contamination IEC 60664-1 Class 2

– IEC 60068-2-60 part 2.60 methods 1 and 4

– Resistance to gaseous contamination: coating is resistant to NO2. CO2. SO2 and H2S.

– Battelle Laboratories Class III (IEC 60721-3-3 Categories 3C1 and 3C2)

Communication

The 505DR can communicate directly with the plant DCS and/or operator control panel using Modbus

TCP or OPC communications.

Serial communication is also supported using RS-232 or RS-485 and ASCII or RTU Modbus.

Control PIDs can perform process control or be used as limiters for speed/load dynamics,

pumping/discharge pressures, cascade, auxiliary, intake plenum, exhaust plenum, and rotor acceleration.

System Protection

– Integrated overspeed protection logic and test functions

– First open indication on 15 shutdown inputs

– External alarm indication on 15 inputs

– Stuck at critical speed band logic

– Bufferless transfer between control modes and during Syscon switchover

– Operation and configuration password security

Operating Conditions

– Ambient air temperature: -25 to +65C

– Humidity Lloyd’s ENV2 Test #1

– Dry heat Lloyd’s ENV3

– Salt Spray: US MIL-STD-810. Method 509.2 proc. 1

– Shock: US MIL-STD-810C, Method 516.2-1 proc. 1B

– Vibration Lloyd’s ENV2 Test #1

– Resistance to particulate contamination IEC 60664-1 Class 2

– IEC 60068-2-60 part 2.60 methods 1 and 4

– Resistance to gaseous contamination: coating is resistant to NO2. CO2. SO2 and H2S.

– Battelle Laboratories Class III (IEC 60721-3-3 Categories 3C1 and 3C2)

Cost-effective design

The 505DR is a G-efficient redundant turbine controller.

It consists of a turbine controller, system sequencer, operator control panel and first-out indicator.

The design minimises external equipment and wiring for easy troubleshooting.

Like the 505XT, the 505DR can be fully configured in the field

(under password control by knowledgeable personnel) and minor functional

changes can be made while the turbine is running online.

Minor functional changes can be made online while the turbine is running.

Like the MicroNet Plus, the 505XT system designates one controller

as the System Controller (Syscon), actively controlling the fan.

The second device is configured as a backup.

The system automatically evaluates the health of the Syscon and initiates a fast switchover in the event of

a failure.

Switchover can also be initiated manually. The system closely synchronises

the Syscon’s software status and memory with the backup,

ensuring that the control output remains stable and does not affect turbine operation (a true ‘bufferless’

switchover).