Estimating Future Harmonic Distortion Levels In Distribution Systems Due To Single-Phase Adjustable-Speed-Drive Air Conditioners: A Case Study

This paper deals with new challenges regarding power quality in ship technology resulting from the novelisation and implementation of IACS (International Association of Classification Societies) rules and requirements. These rules, known as IACS E24 2016/2018, address harmonic distortion for ship electrical distribution systems, including harmonic filters. The reasons for the legislative changes based on a short overview of power quality-related accidents are discussed, after which a brief presentation of the updated IACS rules illustrated by a related DNV GL (Det Norske Veritas Germanischer Lloyd) case study is shown. A key part of this paper includes proposals concerning harmonics and interharmonics, distortion indices and transient disturbances. The aim of these proposals is to unify power quality indices and measurement procedures to maintain effective and comparable criteria for monitoring distortion and establish requirements for ship owners, designers, shipbuilders, classifiers, and crew members of marine objects.

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A Novel Current Injection Circuit for Adjustable Speed Drives

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.f2608.118419 ◽

2019 ◽

Vol 8 (4) ◽

pp. 3933-3935

Keyword(s):

High Efficiency ◽

Harmonic Distortion ◽

Current Injection ◽

Duty Ratio ◽

Switching Frequency ◽

Current Harmonics ◽

Active Devices ◽

Adjustable Speed Drive ◽

Adjustable Speed ◽

Voltage Harmonics

An adjustable speed drive creates the harmonics. The novel current injection circuit does not need any additional active devices. With the significant reduction in current harmonics, the AC input line current is sinusoidal. The ZVS technique is used for all the switches operation. The rectifier diodes are by soft switching. The output voltage regulated by fixed duty ratio with varying switching frequency. The advantages of proposed AC-DC-AC systems are low price, compact, high efficiency, and simplicity. Nine level diode clamped inverter produces the voltage harmonics of 8.75%. The Total Harmonic Distortion (THD) of input current is as low as 7.72 % and power factor as high as 0.99. Theoretical results are verified initially through PSIM simulation and validated with an experimental prototype of 2.5Kw.

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Adjustable-speed drive with single-phase induction machine for HVAC applications

2001 IEEE 32nd Annual Power Electronics Specialists Conference (IEEE Cat. No.01CH37230) ◽

10.1109/pesc.2001.954323 ◽

2002 ◽

Cited By ~ 12

Author(s):

M. Chomat ◽

T.A. Lipo

Keyword(s):

Single Phase ◽

Induction Machine ◽

Adjustable Speed Drive ◽

Adjustable Speed

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Influence of Single-Phase Solar Photovoltaic Systems on Total Harmonic Distortion: A Case Study

Indonesian Journal of Electrical Engineering and Computer Science ◽

10.11591/ijeecs.v12.i2.pp607-611 ◽

2018 ◽

Vol 12 (2) ◽

pp. 607

Author(s):

Chin Kim Gan ◽

Sara Ragab Mahmoud ◽

Kyairul Azmi Baharin ◽

Mohd Hendra Hairi

Keyword(s):

Single Phase ◽

Harmonic Distortion ◽

Total Harmonic Distortion ◽

Photovoltaic System ◽

Design Stage ◽

Small Scale ◽

Photovoltaic Systems ◽

Solar Photovoltaic ◽

The Impact

<span>The installation of small-scale solar photovoltaic system has recently gaining popularity in Malaysia mainly driven by the Feed-in Tariff scheme. Given its relatively small generation capacity, the single-phase solar inverters are not required to comply with power quality standard. Neverthelss, the impact of small-scale solar system on the grid could become significant when the penetration is increasing over the years. In this regard, this paper presents a case study on the influence of single-phase grid-connected solar photovoltaic systems on the total harmonic distortion for current at the point of common coupling. Field measurements have been carried out for a total of 12 single-phase solar systems which were installed at three different locations at Universiti Teknikal Malaysia Melaka. Detailed analyses have been performed to characterize the aggregated current harmonic performance for the overall system. The findings from the presented case study suggest that the current quality from the inverter is highly dependent on the level of inverter output. Hence, the proper selection of the array-to-inverter ratio at the system design stage could greatly improve the overall total harmonic performance performance for current.</span><span>The installation of small-scale solar photovoltaic system has recently gaining popularity in Malaysia mainly driven by the Feed-in Tariff scheme. Given its relatively small generation capacity, the single-phase solar inverters are not required to comply with power quality standard. Neverthelss, the impact of small-scale solar system on the grid could become significant when the penetration is increasing over the years. In this regard, this paper presents a case study on the influence of single-phase grid-connected solar photovoltaic systems on the total harmonic distortion for current at the point of common coupling. Field measurements have been carried out for a total of 12 single-phase solar systems which were installed at three different locations at Universiti Teknikal Malaysia Melaka. Detailed analyses have been performed to characterize the aggregated current harmonic performance for the overall system. The findings from the presented case study suggest that the current quality from the inverter is highly dependent on the level of inverter output. Hence, the proper selection of the array-to-inverter ratio at the system design stage could greatly improve the overall total harmonic performance performance for current.</span>

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Harmonics Current Reduction of a Single-Phase Rectifier Based on Injection Power at Field Side of the DC Motor

Al-Kitab Journal for Pure Sciences ◽

10.32441/kjps.v2i1.143 ◽

2018 ◽

Vol 2 (1) ◽

Author(s):

Aasef Saleh Al-hyali ◽

Hussien Zynal ◽

Addelelah Mahmood

Keyword(s):

Distribution Systems ◽

Single Phase ◽

Second Harmonic ◽

Harmonic Distortion ◽

Dc Motor ◽

Electrical Distribution Systems ◽

Rlc Circuit ◽

In Series ◽

Injection Power ◽

Current Reduction

The AC electrical distribution systems operate at definite and limited levels of voltages and frequencies. Non-linear loads produce non-sinusoidal currents and voltages in the distribution systems. The controlled and uncontrolled single and three phase rectifiers have been utilized in many applications and different industrial fields. The purpose of these applications is to obtain controlled, systematic and smooth DC currents and voltages. These rectifiers generate harmonics in the supply current that negatively affects at the power quality and efficiency of the system. For this reason, reducing harmonics in the current waveform was under investigation by many research groups. Several methods are suggested for minimizing such harmonics, one of that is the harmonic current injection method, which is considered in this paper. In this paper two injection networks are applied at single phase bridge controlled and uncontrolled rectifier which loaded with DC motor. The first suggested injection network involves back to back thyristor in series with RLC circuit in order to adjust the value and phase of the second harmonic injection current. The second suggested injection network includes a new method to get advantages of using the injection power for supplying a field of DC shunt motor. The obtained results show that the total harmonic distortion is reduced by 79.26% with power factor closed to unity.

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