Impact of voltage sags and continuous unbalance on variable-speed drives

Variable speed drives (VSDs) are widely used in various applications mainly in process industry need constant rotational speed. It is developed from power electronic components thus saving energy in its operation. Unfortunately it is susceptible against power quality problem for example voltage sags. The VSD may be disruption or drop out when it is supplied by voltage sags and it is determined by sag characteristics. This study is to investigate effect of voltage sags Types I, II and III on VSD through laboratory testing. The voltage sags characteristics are generated from voltage sag generator (Shaffner 2100 EMC). The effects are presented in susceptibility curves in disruption and drop out conditions. The curves resulted are evaluated by standard curve recommended. Test results show that voltage sag Type I cause the VSD disruption only, whereas two types sag other result in the VSD disruption and also drop out. Evaluation results explain a few test points are in operation area for disruption condition whereas test points for dropping out far below the threshold recommended. Hence the VSD has good quality to voltage sags.

Download Full-text

Power electronics and variable speed drives

Power Engineering Journal ◽

10.1049/pe:20000408 ◽

2000 ◽

Vol 14 (4) ◽

pp. 190-191

Keyword(s):

Power Electronics ◽

Variable Speed ◽

Variable Speed Drives

Download Full-text

Опыт использования частотных преобразователей на объектах ООО «Водоканал»

Vodosnabzhenie i sanitarnaia tehnika ◽

10.35776/mnp.2020.04.08 ◽

2020 ◽

Author(s):

Sergei, Rybel’ ◽

V. Kuninin ◽

S. Gerasimov ◽

A. Bakushin

Keyword(s):

Inrush Current ◽

Electric Motors ◽

Variable Speed ◽

Variable Speed Drives ◽

Technical Device ◽

Advantages And Disadvantages ◽

Subsequent Period ◽

Pumping Stations ◽

Current Water ◽

Pumping Equipment

Приведен опыт применения частотно-регулируемых электроприводов на насосных станциях ООО Водоканал г. Новокузнецка. Приводятся преимущества и недостатки данного технического устройства. Показано, что в настоящее время использование частотно-регулируемых приводов позволило снизить потребление электроэнергии более чем на 20, уменьшить затраты на ремонт и обслуживание, повысить срок службы электродвигателей, уменьшить величину пускового тока, снизить утечки воды и нагрузку на насосное оборудование и трубопроводную арматуру. Применение частотно-регулируемых электроприводов оправдало себя и в тех случаях, когда требуется регулирование параметров для обеспечения технологии (регулирование скорости, производительности и т. д.), приведение параметров оборудования к требуемым значениям без его замены (в расчете на увеличение загрузки оборудования до номинала в последующий период), компенсация суточной неравномерности потребления воды.The experience of using variable speed drives at the pumping stations operated by Vodokanal LLC in Novokuznetsk is presented. The advantages and disadvantages of this technical device are specified. It is demonstrated that currently, the use of variable speed drives provides for reducing the energy consumption by more than 20, reducing the repair and maintenance costs for improving the service life of electric motors for reducing inrush current, water leaks and the load on the pumping equipment and pipeline valving. The use of variable speed drives has paid off even in case where adjusting the parameters to ensure the technology (velocity, performance, etc.) bringing the equipment parameters to the required values without replacing it (in order to increase the equipment load to the nominal value for the subsequent period) compensating for daily irregularities in water consumption are required.

Download Full-text

Adjustable frequency invertors and their application to variable-speed drives

Electronics and Power ◽

10.1049/ep.1964.0369 ◽

1964 ◽

Vol 10 (11) ◽

pp. 389 ◽

Cited By ~ 2

Author(s):

D.A. Bradley ◽

C.D. Clarke ◽

R.M. Davis ◽

D.A. Jones

Keyword(s):

Variable Speed ◽

Variable Speed Drives

Download Full-text

Common-Mode Voltage Harmonic Reduction in Variable Speed Drives Applying a Variable-Angle Carrier Phase-Displacement PWM Method

Energies ◽

10.3390/en14102929 ◽

2021 ◽

Vol 14 (10) ◽

pp. 2929

Author(s):

Abraham Marquez Alcaide ◽

Vito Giuseppe Monopoli ◽

Xuchen Wang ◽

Jose I. Leon ◽

Giampaolo Buticchi ◽

...

Keyword(s):

Carrier Phase ◽

Harmonic Distortion ◽

Harmonic Spectrum ◽

Hydraulic Systems ◽

Variable Speed ◽

Common Mode ◽

Variable Speed Drives ◽

Phase Displacement ◽

Common Mode Voltage ◽

External Component

Electric variable speed drives (VSD) have been replacing mechanic and hydraulic systems in many sectors of industry and transportation because of their better performance and reduced cost. However, the electric systems still face the issue of being considered less reliable than the mechanical ones. For this reason, researchers have been actively investigating effective ways to increase the reliability of such systems. This paper is focused on the analysis of the common-mode voltage (CMV) generated by the operation of the VSDs which directly affects to the lifetime and reliability of the complete system. The method is based on the mathematical description of the harmonic spectrum of the CMV depending on the PWM method implementation. A generalized PWM method where the carriers present a variable phase-displacement is developed. As a result of the presented analysis, the CMV reduction is achieved by applying the PWM method with optimal carrier phase-displacement angles without any external component and/or passive filtering technique. The optimal values of the carrier phase-displacement angles are obtained considering the minimization of the CMV total harmonic distortion. The resulting method is easily implementable on mostly off-the-shelf mid-range micro-controller control platforms. The strategy has been evaluated in a scaled-down experimental setup proving its good performance.

Download Full-text