L&S Hydro Plant Control and Protection Systems History

  • Up to the early 1980s:
    • Most hydroelectric governor, control, protection, and excitation systems were based on proprietary controllers, low-pressure hydraulic technology and hardwired relay logic.  
  • In the mid-1980s:
    • L&S Electric began its revolutionary approach of retrofitting obsolete proprietary governors and controls with solutions based on commercial off-the-shelf (COTS) equipment, such as programmable logic controllers and industrial hydraulic equipment.  These governor and control upgrade projects often included high-pressure hydraulic systems, integrated excitation, and protective relaying systems.  
  • Through 1989:
    • L&S provided 30 COTS-based governor, control, protection, and excitation projects primarily in the Midwest USA.
  • In the 1990s:
    • L&S expanded our reach throughout the US and Canada, providing over 100 COTS-based governor, control, protection, and excitation projects.
  • From 1998 through 2002:
    • L&S greatly enhanced its engineering staff by hiring several Woodward hydro governor industry experts.  
  • From 2000 to 2005:
    • L&S developed pre-engineered mechanical and hydraulic governor equipment such as EHI (electric hydraulic interface), high-volume main distributing valve (400 to 15,000 liter/min), high flow pump unloader valve, air over oil upclosing float valve, low-pressure accumulator / HPU instrumentation, kidney loop filtration system, MOST (mechanical overspeed system) and SSG (Speed Signal Generator).  
  • In 2007:
    • The Industry-leading LS-MRT 1.0 (multiple runner type) pre-engineered, configurable hydroelectric governor controller was released.  
  • In 2008:
    • L&S Electric finished the design of our IEEE compliant, pre-engineered N-Series governor hydraulic power unit (HPU) designs to cost-effectively meet the needs of the hydroelectric industry.  
  • In the 2000s:
    • L&S Electric provided the hydroelectric industry with over 200 projects.
  • In 2012:
    • Next-generation LS-MRT 2.0 was released.
  • In 2016:
    • The L&S Electric state of the art LS-AES (advanced excitation system) was released.  See additional LS-AES details below.
  • In 2018:
    • The L&S Electric LS-AGS (advanced governor system) hydroelectric governor was released.

To date, we have supplied governor, control, protection, and excitation systems for over 1500 generating units, ranging in size from 75 kW to 600 MW.  Our equipment is installed on over 35GW of generation in 22 countries. 


Service & Quality

  • Dedicated project team and PMI methodology ensures solutions are delivered on time and on budget
  • Design, manufacturing and integrated factory testing all under one roof to allow for efficient, high-quality, controlled solutions 
  • Certified to ISO 9001 Quality Management Standards
  • Our manufacturing facility is certified to UL® 508 
  • Committed to our customers with Legendary Service 24 hours a day, 7 days a week, 365 days a year


Value & Reliability

  • Focus on the total cost of ownership
  • Designs are based on commercial-off-the-shelf open architecture hardware that provides a flexible and cost-effective alternative to the proprietary systems
  • Cost-effective spare parts that are available via multiple channels
  • Designed with proven technologies and validated IEEE models that meet or exceed industry standards
  • User-friendly interfaces include advanced monitoring and control features
  • Built-in diagnostics allows the equipment to be serviced down to the module level with in-house resources  



  • Hydro Plant Control and Protection Systems
    • Digital Hydraulic Governors
    • Digital Excitation Systems
    • Unit and Plant Control Systems
    • Protection Systems


Value-Added Services

  • System modeling, model validation
  • System configuration
  • Installation Engineering
    • Mark up of existing customer drawings (by hand or electronically)
    • Specify cabling for scope of supply
    • Installation wiring to/from list (Excel spreadsheet)
  • Customer witness testing at L&S Electric Factory
  • Customer training services at site or in factory
  • Turnkey installation/removal services – utilizing local contractors and L&S Electric supervisor
  • Recommended spare parts
  • Customizable after-sale service contracts



Hydroelectric Power Generation

  • Digital Hydraulic Governors
  • Digital Excitation Systems
  • Unit and Plant Control Systems
  • Protection Systems

Fossil Fuel Power Generation

  • Digital Excitation Systems

Municipal and Heavy Industrial 

  • AC Synchronous Motor Excitation Systems

OEM Panel Manufacturing