Summary
Read more on ELECTRAPart B – Black-box models
The reliable and safe operation of the transformer requires that the dielectric stresses imposed by transient overvoltages are kept within acceptable limits. Black-box models are terminal equivalents of the transformer. Such models can be used in general transient studies where the objective is to calculate overvoltages that occur in the system, external to the transformer. CIGRE JWG A2/C4.52 has reviewed the various black-box models with consideration to parameter determination, accuracy and to the possible inclusion of such models in electromagnetic transient simulation programs for use in general transient studies. The model parameters can in principle be calculated via a white-box model, and the accuracy of the model is then limited by the accuracy of the white-box model. The highest accuracy is usually obtained by performing measurements of small-signal frequency sweeps on the transformer's terminals, e.g., of terminal admittance and voltage transfer between terminals. A model suitable for electromagnetic transient simulations can thereafter be calculated by fitting a rational model to the data. The TB reviews alternative measurement setups and methods for model extraction from the measurement data. Often, highly accurate models can be obtained. It is to be observed that such black-box modeling from measurements can be a challenge, even with the use of a dedicated measurement setup and trained personnel. This TB is one of five TBs from the JWG.
Table of content
1. Introduction
1.1. Background, JWG activities, Results
1.2. Black-box models
1.3. Applications of black-box models
1.4. Transformer and reactor characteristics
1.5. TB Organization
2. Behavioral descriptions
2.1. Definitions
2.2. Interacting descriptions (frequency domain)
2.3. Non-interacting and hybrid descriptions (frequency domain)
2.4. Behavioral descriptions in the time domain
3. Data generation using white-box models
3.1. "Frequency Scan"
3.2. Admittance matrix elements
3.3. Impedance matrix elements
3.4. Voltage transfer matrix elements
4. Data generation using vector network analyzer (VNA)
4.1. The VNA instrument
4.2. Admittance measurements
4.3. Voltage transfer measurements
4.4. Hybrid measurements
4.5. Modal measurements
4.6. Procedures for enhancing the measurement accuracy
4.7. Removing systematic errors caused by imperfect measurement setup
4.8. Verification of data consistency
4.9. Simplified measurements
5. Data generation using SFRA setups
5.1. SFRA instruments
5.2. Admittance measurements
5.3. Influence of measurement cables
6. Model extraction
6.1. Introduction
6.2. Model formulations
6.3. Physical requirements
6.4. Model parameter estimation
6.5. Passivity enforcement
6.6. Mode-Revealing Transformation (MRT)
6.7. Validation of model accuracy
6.8. Single-terminal modeling using lumped circuit elements
6.9. Passivity correction of measurement data
7. Transformer core non-linear effects
8. Shunt reactor behavior
8.1. Reactor behavior compared to transformer behavior [60], [61], [62]
8.2. Black-box modeling
9. Examples
9.1. Model interfacing with EMT programs
9.2. Single-phase transformer: modeling from measurements
9.3. Single-phase transformer: modeling from white-box model
9.4. Three-phase transformer: modeling from measurements
9.5. Three-phase shunt reactor: modeling from measurements
9.6. Single-phase shunt reactor: simplified modeling from white box model
10. Recommendations
10.1. Scope of black-box models
10.2. Application purposes and model requirements
10.3. Data generation
10.4. Model extraction
10.5. Compatibility with EMT programs
Additional informations
| Publication type | Technical Brochures |
|---|---|
| Reference | 901 |
| Publication year | |
| Publisher | CIGRE |
| ISBN | 978-2-85873-606-5 |
| Study committees |
|
| Working groups | JWG A2/C4.52 |
| File size | 7 MB |
| Pages number | 88 |
| Price for non member | 170 € |
| Price for member | Free |
Authors
Bjørn Gustavsen, Convenor (NO), Angelica Rocha, Secretary (BR),
Alvaro Portillo (UY), Andrzej Holdyk (NO), Anniyappan Palani (DE), Baudilio Valecillos (CH), Behzad Kordi (CA), Bogdan Andriienko (UA), Carlos González-García (ES), Casimiro Álvarez-Mariño (ES), Daniil Matveev (RU), Davor Vujatovic (UK), Ebrahim Rahimpour (DE), Enrique Mombello (AR), Esteban Portales (CA), Federico Portillo (UY), Guillermo Andrés Díaz Flórez (CO), Gustavo H. C. Oliveira (BR), Hans De Herdt (BE), Hans Kristian Høidalen (NO), Ji-Hong Kim (KR), Jos Veens (NL), Jose Carlos Mendes (BR), José Francisco Lofrano (BR), Juliano Montanha (BR), Luiz Fernando de Oliveira (BR), Marc-Olivier Roux (CA), Maxym Ostrenko (UA), Michel Rioual (FR), Mikhail Frolov (RU), Oliver Sterz (DE), Ricardo Castro Lopes (PT), Robert Degeneff (US), Rodrigo Ronchi (MX), Rogerio Azevedo (BR), Shikin Jamil (UK), Tobias Röhrl (DE), Triomphant Ngnegueu (FR), Xosé López-Fernández (ES)
Keywords
power transformers, reactors, power systems, technical performance
Other parts
- High-Frequency Transformer and Reactor Models for Network Studies - Part A: White-Box Models
- High-Frequency Transformer and Reactor Models for Network Studies - Part D: Model interfacing and specifications
- High-Frequency Transformer and Reactor Models for Network Studies - Part C: Grey Box Models
- High-Frequency Transformer and Reactor Models for Network Studies - Part E: Measurements and transformer design details
