Standstill Frequency Response Tests Research Articles

The effects of noise on frequency-domain parameter estimation of synchronous machine models

The authors present results of a study conducted to evaluate the effects of measurement noise on the estimation of machine parameters from standstill frequency response test data. Results obtained indicate that, because the test data are inherently noise-corrupted, multiple solution sets can be obtained. Moreover, some of the estimated machine parameters could be unrealistic. It is shown that the results are very sensitive to the value of armature resistance used in the data analysis. Even a 0.5% error in the value of armature resistance could result in unrealistic estimation of the machine parameters.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Determination of synchronous machine stator and field leakage inductances from standstill frequency response tests

It is shown that the identification of d-axis stator and field winding leakage inductance appears to be possible using standstill frequency-response rests with field open (applying voltage to the stator), and with the stator open (applying voltage to the field). Measurements of applied and induced voltages and currents to the excited winding form a sufficient set of data to identify the leakage inductances of both the stator and field windings. This method is illustrated and applied to limited published standstill frequency response test data. The results indicate a variation in leakage inductance, depending on the frequency of the test. The reasons for such variations are explored and hypothesized.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

A Study of the Frequency Response of Turbogenerators with Special Reference to Nanticoke G. S.

The results from the standstill frequency response tests on three selected turbogenerators are critically examined. Particular attention is paid to the Nanticoke machine. A reason for the large difference between this machine's performance as predicted using data derived from standstill tests as compared to that predicted using data from on-line tests is proposed. Use is made of the finite element method linked to simple external circuits.

Synchronous Machine Modeling by Standstill Frequency Response Tests

Synchronous Machine Modeling by Standstill Frequency Response Tests

Synchronous Machine Modelling by Standstill Frequency Response Tests

The synchronous machine is modelled in terms of operational impedances derived from standstill frequency response measurements. A curve-fitting procedure in the complex plane yields all the parameters including the armature resistance without having to pre-process the data or make other measurements. The validity of the model is demonstrated for a micro-alternator by comparing the sudden short-circuit current predicted by the model with that obtained experimentally. Frequency response data obtained at different current levels are used to show that a useful model can be derived from tests at low per-unit current.

Synchronous Machine Models by Standstill Frequency Response Tests

An approach to determining synchronous machine parameters by low-voltage frequency response tests with the machine stationary will be described. The tests are simple and safe. In addition, they provide a more detailed and complete model of the machine than the accepted standard methods/1/. The standard tests rely heavily on the measurement of large transients. As such, they are susceptible to any changes in saturation during the course of the measured transient. Furthermore, the accuracy and resolution with which a single transient can be measured are frequently insufficient to provide the detail required to model the solid iron rotor of a turbogenerator. The test method described herein avoids both of these problems as well as providing complete q-axis data which is not done by the standard tests.

Synchronous Machine Models by Standstill Frequency Response Tests

Synchronous Machine Models by Standstill Frequency Response Tests

Standstill Frequency Response Modeling and Evaluation by Field Tests on a 645 MVA Turbine Generator

This paper describes the testing and analysis performed under EPRI sponsorship on a 645 MVA synchronous generator to determine the suitability for dynamic simulations of a generator model derived from standstill frequency response tests. Transmission line switching tests were performed as a basis for model evaluation. Models based on standstill frequency response tests and standard design data were used in simulations of these switching events. Although the standstill frequency response model resulted in suitable simulation results, no improvement was achieved over that using the standard design data.