Project Experience

ELECTRICAL DISCHARGE MACHINING OF GENERATOR BEARINGS

Led the effort to get to the root cause and solve the EDM problem caused by non-insulated sensors connected to generator bearings, and inefficient bearing insulation.

WIND TURBINE PITCH SLIP-RING FAILURE

Investigated the premature failure of newly designed wind pitch system slip-rings. New, improved, brush material was introduced and changes to accelerated lab test and field test were implemented based on the findings.

GENERATOR FAILURE ANALYSIS

Participated in multiple generator failure analysis. Failures were related to internal design issues, brushes, and slip-ring premature wear.

GROUNDING ISSUES

Led a number of investigations of grounding issues in wind farms or power plants. Investigated quality meter malfunction at a power distribution substation caused by improper grounding at the power plant. Led a root cause analysis of UPS failures caused by grounding loop issues.

ELECTRICAL NOISE AND SWITCHING TRANSIENTS

Investigated electrical noise caused by converters and switching transients. The cause of failure was identified by oscilloscopic fault data.

LIGHTNING PROTECTION FOR CARBON FIBER BLADES

Led the root cause investigation of carbon fiber blade damage and worked with the engineering to develop repair solution and design change.

FIRE INVESTIGATIONS

Participated in wind turbine fire inspections for fires caused by cables, generators, electrical systems, and mechanical components.

NEW PRODUCT INTRODUCTION

MONITORING AND DIAGNOSTICS FOR WIND TURBINES

Led a program to develop condition monitoring system and wind drive train asset management.

Initiated a process to detect and report turbine and sensor outliers to detect potential anomalies across entire fleet.

LARGE GENERATOR UPRATE

Led a new product introduction program to uprate and upgrade large liquid cooled generators by revisiting old design limits and offering innovative technical solutions and product development to increase generator ratings. Solutions included revisiting Electromagnetic core-end stepping design and offering core-end cooling baffle.

OUTAGE INTERVAL EXTENSION

Participated in a program to develop a financial risk management tool to drive generator maintenance decisions based on machine condition, repair history, and repair cost.

Led a multi-functional team to develop a new and comprehensive monitoring systems for generators. Advanced partial discharge analyzer, fiber optics wedge tightness sensor, and multifunction sensor were developed, tested and validated as part of the program. Diagnostics were used to create rules for future prediction and analysis.

CODES AND STANDARDS

Dr. Salem is a Co-Chair of the IEEE PES SPDC Working Group 3.6.11 on Wind Power Facilities Electrical Protection Guide and a member of the International Council on Large Electrical Systems (CIGRE) working group C4.36 on “Winter Lightning Parameters and Engineering Consequences for Wind Turbines”.

Led the CIGRE working group to write a guide on “Economic Evaluation of Refurbishment/Replacement Decisions on Generators”. A report was issued in 2015.

Participated in rewriting IEEE Std. 67-2005 Guide for Operation and Maintenance of Turbine Generators.