Hybrid Power Quality Compensator Design for Co phase Power Supply System in Electrified Railway
| dc.contributor.advisor | Getu, Gabisa (Mr.) | |
| dc.contributor.author | Abrha, Gebremichael | |
| dc.date.accessioned | 2019-01-01T08:18:39Z | |
| dc.date.accessioned | 2023-11-04T15:17:06Z | |
| dc.date.available | 2019-01-01T08:18:39Z | |
| dc.date.available | 2023-11-04T15:17:06Z | |
| dc.date.issued | 2015-04 | |
| dc.description.abstract | Poor power quality and phase splitting are the main issues in electric railway system. Co phase traction power supply system provides continuous power to traction loads without neutral sections. In this thesis hybrid power quality compensator design for minimum DC operation voltage under comprehensive fundamental and harmonic compensation is being proposed and introduced. The hybrid power quality compensator (HPQC), in which a capacitive coupled LC structure is added, is thus proposed for lower operation voltage. The proposed HPQC is composed of a single phase back to back converter with a common DC link. It is connected to the secondary side of a 132kV/27.5kV V/V transformer. Since locomotive loadings are mostly inductive, a capacitive coupled impedance design is adopted in proposed HPQC to reduce the compensator operation voltage. Reduction in operation voltage can effectively reduce the device ratings and the initial cost of the compensator. The operation voltage of proposed HQPC can be minimized when the parameters are properly designed. The design procedures of HPQC parameters are explored using vector diagrams and mathematical derivations. The parameter design for minimum HPQC operation voltage is derived based on constant rated load power factor and capacity. The HPQC operation voltage rating is around 0.4824 under comprehensive compensation. This corresponds to a DC link voltage of around 17.06KV. This shows that under comprehensive compensation, with a proper LC parameter design, a lower dc voltage operation can be achieved. Co phase traction power supply system with HPQC is modeled and simulated using Matlab/Simulink. The simulation result shows that the three phase source harmonics and unbalance are eliminated. This can be verified by its harmonic distortions of current 0.54%, 0.51% and 0.08% at phase A, phase B and phase C respectively, and unbalance of 2.43%. Since the negative sequence current 12.69 is smaller than the threshold value 34.99 then the system unbalance satisfies the standard. Simulation results show the HPQC could compensate unbalance current and current harmonics simultaneously. | en_US |
| dc.identifier.uri | http://etd.aau.edu.et/handle/123456789/15420 | |
| dc.language.iso | en_US | en_US |
| dc.publisher | AAU | en_US |
| dc.subject | Co phase traction power supply system | en_US |
| dc.subject | hybrid power quality compensator | en_US |
| dc.subject | V/V transformer | en_US |
| dc.subject | minimum dc operation voltage | en_US |
| dc.subject | unbalance current | en_US |
| dc.subject | current harmonics | en_US |
| dc.title | Hybrid Power Quality Compensator Design for Co phase Power Supply System in Electrified Railway | en_US |
| dc.type | Thesis | en_US |