Power system analysis studies are a vital component of a secure and safe electrical supply. The analysis of the network/facility design defines a comprehensive base for the design and the pre-selection of equipment in order to operate safely, cost-effectively, reliably and with a high level of availability. The analysis provides suitable modelling to ensure the Energy Regulator requirements are met, provides a base for future network/facility changes and provides a thorough and legislated verification of the proposed design.
The Power System Study will review the integrity, protection and performance of the overall power generation facility or substation. The system components are fundamentally made up of: grid supply or generation units, switchgear, transformers, cabling, CTs / VTs, protection relays and protection devices.
Power system study software is used to complete the power system assessment. The software tool must be industry recognised and very well respected technically by industry experts to provide confidence in the results. A tool is only as good as the operator and must be completed by a well-qualified power systems engineer to provide correct outcomes.
The study breakdown will generally consist of the following key functions:
- - Data Gathering Process
- - Data Review and Client Communication
- - Compiling Cable and Equipment Data
- - Building Project SLD Model
- - Load Flow and Short Circuit Analysis
- - Protection Coordination Study
- - Arc Flash Study Review
- - Power Study Report with Overview
- - Risk Assessment and Mitigation Analysis
- - Project Management
This is the process of acquiring all the data for the power system model. Where data cannot be provided, the client will need to provide credible data assumptions. Powertech assists in this process and has a good library of information. The following is an example of the type of data that will be required for a typical power system study:
|Switchboards||kV, type, gap, working distance, glove class, isolation model.|
|MCCs||kV, type, gap, working distance, glove class, isolation, model|
|Motors||kW, kV, X/R, Xsc, %LRC, model.|
|Loads||MVA, kV, %motor load, %LRC, X/R, X', Td', model.|
|VSDs||Pulses, pf, model.|
|Generators||MW, kV, pf, Xd'', Xd', X/R, type, grounding method, model.|
|Cables||Z, R, X, Y, temp C, length, kV rating, model.|
|As Built Load Lists||Detailed load list that includes all LV and HV loads (kW, pf, eff, Z)|
|Cable Schedule||Details providing: length, type, installation method|
|Cable Layout Drawing||Routing details, installation details|
|Equipment Lists||Equipment information to provide model numbers|
|Detailed Single Line Diagrams / Schematics||As Built|
|Switchboard and MCC General Arrangements||Showing details of relays and other equipment|
Protection Settings Report
|1. Detailed information on relays used and settings used for each relay type|
|2. Current / voltage transformer: types, and class.|
Electrical Engineering Services
Powertech benefits in providing an overall solution. For example, a harmonic study is required to meet the requirements of the energy provider’s harmonic guidelines and connection agreement. A study is completed and the results verified with Powertech’s field monitoring equipment. The practical results can then be optimised back into the model providing a realistic model with appropriate checks and balances. It is not enough to do a desktop study without providing sufficient testing of the model. Powertech can offer this service.
Powertech Electrical Engineering Services provides a collaborative, cohesive and sustainable overall engineering team capability. Professional consulting electrical engineers with over 30 years’ experience who work actively with Powertech’s senior field technicians/electricians and HV auditors.