The load test is performed to establish the performance of a synchronous generator under load conditions as part of commissioning tests at a site. The test involves operating the generator at rated speed and voltage, synchronizing it to the power system, and gradually increasing the load up to full load or maximum possible load while measuring electrical data. The data is compared to contract and design values to check if performance is satisfactory. Any deviations require a nonconformity report according to PNG Power standards.

1. LOAD TEST
Table of Content:
1 Objective.........................................................................................................
2 Scope..............................................................................................................
3 Referenced Documents .................................................................................
4 Definitions and Abbreviations.........................................................................
5 Preparation......................................................................................................
6 Conduction of test: .........................................................................................
7 Proceeding in case of deviations ...................................................................
8 Copyright .......................................................................................................
1 Objective
The load test is performed to establish the performance of the synchronous generator
under load conditions. The load test is part of the commissioning tests at site. From the
load test data the following machine characteristics are determined:
- performance characteristic (Vee-curves)
2 Scope
Synchronous machines of all types at site, excitation brushless or static
3 Referenced Documents
IEC 34-1
EN 60034-1
4 Definitions and Abbreviations
None
5 Preparation
- For measurements the installed plant instrumentation is used
- Check that all protection relays are in operation
- Set the generator in automatic condition (speed governor and excitation system)
6 Conduction of test:
- Operate the unit at rated speed and rated voltage
- Synchronise the unit to the power system
- Supply small power to the system, then check, whether all instruments, excitation
system and generator are in the proper condition
- Increase load stepwise (preferably approx. 25 % steps) up to full load (or maximum,
possible load if lower). Measure armature currents, voltages, power and power factor,
and field current of generator or exciter as appropriate
- Continue operation of the unit at full load (resp. maximum attainable stable load
condition) for several hours, measure required electrical data and read all temperatures
of the generator bearings, RTD’s and thermometers of the cooling system, check
bearing vibration at both ends.
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2. Compare measured data to contract and design values, and to measured values from
test reports of work shop tests on the tested machine, or type test reports of a similar
machine and exciter. If satisfactory, the reliability test can be started.
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3. 7 Proceeding in case of deviations
Any nominal value, minimum value, maximum value, tolerance etc given in an instruction
is intended to serve for quality control purposes only. In the case of deviations, a
nonconformity report has to be written according to PNG Power Standard
8 Copyright
This Document is properly of PNG Power internal use only and must neither be copied.
Neither is it to be handed over nor in other way communicated to a third party.
Infringement will lead to prosecution.
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