Electrical Technical Services Group Power Systems Analysis and Special Consulting Services

Transcription

1 Electrical Technical Services Group Power Systems Analysis and Special Consulting Services Electrical Engineering

2

3 reliable POWER Today s complex industrial electrical power systems require special analysis to establish performance acceptability. KBR has been a recognized leader in the field of power system analysis for over twenty-five years, contributing to actually developing many of the standards and practices currently in use by the industry. In addition, the Electrical Engineering organization at KBR is unique among E&C firms, differentiated by a staff of power system engineering experts, the Electrical Technical Services Group (ETSG). The ETSG can provide the full range of analytical engineering services essential for the effective planning, design, and reliable operation of even the most complex electrical power system. Engineering services that can be provided as either a stand-alone effort or in support of a multi-discipline project include: Power Distribution System Studies Plant Power System / Equipment Surveys System / Equipment Grounding Evaluations Tie Line (Watt & Var) Control / Load Shedding Systems On-site Power Systems Seminars The Power Distribution System Studies mentioned are used to predict the performance of a power distribution system. These studies determine the behavior of and the operating duties imposed on the electrical equipment and components applied within the system during normal and abnormal events. Such studies include: Fault Analysis / Breaker Application (Short-Circuit) Studies Load Flow & Motor Starting Voltage Drop Studies Load Analysis Studies Protective Device Coordination Studies Motor Starting Torque / Acceleration Time Studies Arc Flash Hazard Assessment / Personal Protective Equipment (PPE) Studies Grounding, Bonding, and Ground Mat Design Studies Transient Stability Studies Cable Ampacity Studies Lightning and Surge Protection Studies Harmonic Analysis Reliability / Availability Studies State-of-the-art computer-based technology is employed in performing all these analytical investigations. Several types of power system studies are illustrated and a brief description of the studies available appears on the following pages.

4 Protective Device Coordination Time-Current Curve Time-current plots of protective device characteristics and equipment ratings provide graphical evidence that equipment is properly protected and protective devices are selective with one another. These curves are created using commercially available software. Device Setting Summary sheets provide a complete listing of the recommended settings and calibrating data for plotted protective devices along with the settings or ratings for all other protective devices in the system. These sheets greatly simplify and streamline the work performed by the field technicians setting the devices. Additionally, relay configuration files generated by ETSG are downloaded directly into microprocessor-based relays. This approach virtually eliminates relay setting errors and further reduces commissioning time. Short-Circuit Calculations The total short-circuit current and contribution from each circuit element complete with corresponding X/R ratios are calculated at each bus in the system. These values can be compared with the rating of the switching / interrupting devices to confirm that proper devices have been selected. Line-to-ground faults as well as three-phase faults can be evaluated.

5 Ground Mat Potentials For a given ground grid design and soil condition, the mesh and perimeter touch voltages at the earth s surface are calculated and compared with tolerable (safe) touch potentials. The locations of dangerous voltage levels, where present, are precisely identified so that appropriate corrective measures can be incorporated into the ground grid design. Transient Stability Studies The dynamic response of prime movers / generators and induction / synchronous motors can be modeled and system performance studied for user-defined upset conditions such as faults, line or machine outages, step-load changes or motor starting. These studies will guide system design, protective device settings, or load shedding requirements to ensure that the power system will regain operating equilibrium following the upset. Results can be graphically represented by a plot of machine / system parameters with time.

6 Electrical Power System y Studies Fault Analysis / Breaker Application Study Calculates per ANSI or IEC standards momentary and interrupting fault duties at every system bus. Compares circuit breaker, fuses and non-fusible equipment ratings with imposed duties to verify that device start-up circuit capabilities are adequate. Protective Device Coordination Study Plots the time-current curve at specified values for each protective device applied on the power system and identifies device calibration points. Arc Flash Hazard Assessment Using information determined from the protective device coordination study and short-circuit study, this analysis calculates arc flash energy exposure levels for defined operations or switching conditions at each plant bus location. These exposure levels are then used to identify Personal Protective Equipment (PPE) and working distances as prescribed by NFPA 70E and IEEE Load Flow Study Calculates the system steady-state bus voltages, kilowatt and kilovar branch loads for motor and static loads. Accepts capacitors, off-nominal transformer taps and generator loading levels, and allows investigation of various operating modes. Reports provided on buses with abnormal voltages, branch loading / losses and total system loading / demand conditions. Motor Starting Voltage Drop Study Calculates the system voltage levels before and just after the impact of a motor being started, referred to as a snapshot voltage drop calculation. Motor Starting Torque / Acceleration Time Study Using motor / load inertia and torque values, calculates the motor voltage and output torque during the accelerating period, and determines the overall starting time. Ground Mat Potential Study Determines step and touch potentials to evaluate shock hazards in substations or other ground mat environments. Performs a detailed mesh-by-mesh analysis of the mat to precisely identify hazard locations and optimal design remedies. Transient Stability Study Using the dynamic characteristics of prime movers and synchronous machinery, calculates the response of these machines to various system disturbances and plots the machine variables with respect to time in order to reveal any unstable operating conditions requiring load shedding or other corrective measures. Cable Ampacity Study Using the Neher-McGrath calculation method, calculates the ampacity or operating temperature of multiple cable circuits direct buried or in underground duct banks. Harmonic Analysis With harmonic producing loads on a system having power factor correction capacitors: (a) calculates the system bus voltages, kilowatt and kilovar branch loads at various multiples of fundamental frequency; (b) calculates the total voltage and current values at each bus so that unacceptable voltage distortion and the frequency where harmonic amplification exists are easily identified; and (c) can be used to evaluate the effectiveness of harmonic filters and tuning reactors. Reliability / Availability Studies Using standard failure rates and outage duration times for electrical components: (a) calculates the statistical availability (expected percentage of up-time) of a power system; and (b) can be used for comparison of alternative system designs from an overall availability standpoint and to evaluate the worth of redundant circuit designs within a specific system. Note: All Electrical Power System Studies conform to procedures and practices described in the latest version of IEEE Standard 399 Recommended Practice for Industrial and Commercial Power Systems Analysis, (The Brown Book) as well as all other related standards on the subject. KBR uses commercially available software programs to perform the calculation for all these studies. For further information, contact the KBR Electrical Chief Technology Engineer.

7 Representativep Listing g of Power System y Studies Esso Exploration & Production Chad, Inc. Chad Development & Export System Facility Project Power system: Four in-plant 42 MW, 13.8 kv gas turbine generators (GTG); 33 kv Gas Insulated Switchgear (GIS) main substation; 66 kv and 33 kv transmission lines to remote substations; and several 33 kv, 6.6 kv, and 400 V substations. Short-circuit, load flow, motor starting, transient stability, protective device coordination, insulation coordination, harmonic load flow, and ground mat potential studies. Shell Philippines Malampaya Project, Offshore Philippines Power system: Three 8 MVA, 4.16 kv GTGs; two 1.3 MW, 480 V emergency generators; 4.16 kv and 480 V distribution systems. Short-circuit, load flow, motor starting, transient stability, and protective device coordination studies. ExxonMobil Kizomba FPSO FEED Project, Offshore Angola Power system: Three 35 MVA, 13.8 kv GTGs; one 5 MVA, 4.16 kv essential generator; and 1.5 MW emergency generator; and 15 kv subsea cable distribution system to remote platforms. Electrical system optimization studies for distribution voltage selection, load flow, short-circuit, and motor starting analysis. Exxon Singapore Olefins Project, Jurong Island, Singapore Power system: kv and kv substations, two 135 MVA base-rated utility-tie transformers, two 104 MVA GTGs, two 100 MVA base-rated generator transformers, two 75 MVA distribution transformers. Short-circuit, load flow, motor starting, motor re-acceleration, and protective device coordination studies. Farmland Mississippi Chemical Ammonia Project, Point Lisas, Trinidad Power system: 13.8 kv substation with 16 MW STG and utility tie. Short-circuit, load flow, motor starting, transient stability, and protective device coordination studies. Maraven Refinery Expansion Project, Cardon, Venezuela Power system: New kv substation with two 140 MVA transformers and current limiting reactors that tie an Independent Power Producer (IPP) and this expansion project into the existing facility, which contains three GTGs and four STGs. Short-circuit, load flow, motor starting, transient stability, load shedding, motor re-acceleration, and protective device coordination studies.

8 Electrical Engineering 601 Jefferson Avenue Houston, Texas Tel: Attn: Electrical Chief Technology Engineer Worldwide Headquarters 4100 Clinton Drive Houston, Texas Tel: K /03 Printed in the U.S.A Kellogg Brown & Root a Halliburton company Printed by KBR Communications