The corona-generated audible noise (AN) factor is an important consideration in the design and operation of ultrahigh voltage direct current (DC) alternate (AC) transmission lines. Due to differences discharge process space charges between DC AC corona discharge, from has different characteristics. This paper conducts a series experiments by measuring time-domain waveforms single source under voltage. Sound pressure pulses are extracted correlation analysis, then detailed comparison basic...

The corona-generated audible noise (AN) has become one of decisive factors in the design high voltage direct current (HVDC) transmission lines. AN from lines can be attributed to sound pressure pulses which are generated by multiple corona sources formed on conductor, i.e., In this paper, a detailed time-domain characteristics pulses, DC discharges over surfaces stranded conductors, investigated systematically laboratory settings using cage structure. amplitude pulse and its time intervals...

Although transverse wind exerts an important influence on the distribution of ion current density under HVDC transmission lines, very few experiments involving stable have been used to verify numerical model. To overcome variability natural wind, a low-speed tunnel was produce in this research. An experimental platform set up tunnel, measure dc wires. Based experiment, exerted significant over current. The model discussed and results showed reasonable agreement with measured values for...

The sound pressure level (SPL) has been generally accepted in the measurement and evaluation of degree nuisance to corona-generated audible noise from transmission lines. Quite many scholars have studied spectrum statistical characteristics SPL lines through long-term frequency measurement. In fact, corona sources on usually act as emitting pulses with random amplitudes time intervals, yet their correlation barely investigated. this paper, a series experiments single positive source coaxial...

In this paper, the time-domain measurement method for audible noise is employed to study time and frequency domains characteristics of generated by single corona discharge under DC AC voltage in a coaxial geometry. The results show that from positive negative both consist series random sound pressure pulses amplitudes are larger than those discharge. As test, it has periodic component with 50Hz fundamental accompanied pulse trains mainly near peaks voltage. When applied further increased,...

With the rapid development of HVDC transmission projects in China, situation greenhouses existing under lines is becoming increasingly common. When are corona, ionic space charges produced by corona discharge vicinity conductors basically driven electric field to ground. The presence with insulating film will accumulate charges, which makes nearby distorted. However, accurate modeling hasn't been achieved because difficulty getting charge distribution at surface film. In this paper, a set...

The previous research work has dealt with corona characteristics of conductors coated different types contaminations, while the thickness is rarely considered. To fully study effects conductor surface condition on photon count and streamer pulses, thicknesses contamination are investigated compared a clean one. An experimental system based an indoor cage was established to exclude interference from environmental factors. In experiment, kaolin used as coating conductors. Experimental results...

Corona-generated space charge density is an important quantity that helps describe the electrical environment in vicinity of High Voltage Direct Current (HVDC) transmission lines. This paper develops a device based on ion counter method to measure under DC test wire, which used simulate HVDC line. An experiment carried out analyze various factors affecting measurement. Another experiment, comparing with indirect rotating field-mill often at ground level, conducted verify feasibility and...

HVDC transmission lines operating in polluted areas may absorb a large amount of contamination, which seriously affects the corona discharge and its associated audible noise, electric field, ion current density from lines. To fully study effects conductor surface condition on photon count dc conductors coated with different kinds contamination were investigated compared clean one. Scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) analysis SPIP employed to characterize...

Abstract A simplified dynamic model of the rotor-bearing-support system is established considering influence pedestal flexibility. The vibration characteristics with a flexible are analyzed. There two resonance peaks during run-up process for this kind system. It generally thought that stiffness difference in vertical and horizontal direction main cause double peak phenomenon. results paper show support also causes shaft relative cannot reflect rotor unbalances well near zone. In case,...

The rapid growth of photovoltaic (PV) installations has resulted in an imbalance between generation and demand, leading to difficulties accommodating utilizing the generated electricity effectively. To address this issue, paper proposes energy storage sharing-based coordinating operation framework for multiple PV stations fully utilization enhance overall efficiency PV. In study, we consider operating costs PV, propose a strategy coordinated based on sharing. Furthermore, solve model using...

In the context of electricity market reform and increasing integration renewable energy, service provider (ESP) has assumed role intermediaries in transactions. However, unpredictability energy uncertainty load demand expose ESPs to risks during spot To address these issues, this study first develops an operation model for ESP under Subsequently, leveraging credibility theory, price are treated as fuzzy variables, a chance constraint is formulated multiple uncertainties. The aims maximize...

Accurately estimating the core power losses under trapezoidal induction waveform, and analyzing its variation with duty cycle, are essential for elaborate design of high-frequency transformers used in dual-active-bridge (DAB) dc-dc converters. In this paper, waveform theoretically predicted by considering specific role hysteresis, classical excess loss components. The fixed coefficients a wide frequency spectrum up to 10kHz validity prediction components calculated using polynomial...

Noncontact measurement of electrostatic voltage is required to study the charges in HVDC transmission system.The calibration platform noncontact voltmeter studied.The electric field near probe calculated by FEM.Based on calculation, edge effect and applied calibrating plate electrode are analyzed.

Corona discharge may occurs when the lighting conductors are close to HVDC transmission lines.In this paper, ion flow electric field on surface of is calculated by flux tracing method.According results, influences height, radius and distance lines discussed, approaches reduce strength given.