Bidirectional ICPT Harmonic Elimination System Based on Harmonic Extraction and Inverse Injection Method

The purpose of the review - presentation of clinical scientific data based on current evidence of information on the management of patients with stress urinary incontinence, the effectiveness and safety of periurethral injections of various bulking substances. Material and methods. А review of Russian and foreign sources on the prevalence, etiopathogenesis, diagnosis and treatment of stress urinary incontinence in women, in particular the injection method. Results. The review presents data of the etiopathogenesis, diagnosis and treatment of stress urinary incontinence in women, depending on the severity of the pathology. Analyzed the data of periurethral injection of various bulking materials, their effectiveness and safety.

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Research of Bitumen-Mineral Mixture Applied for Patching Repair of Road Pavements Using Jet-Injection Method

Stroitel nye Materialy ◽

10.31659/0585-430x-2017-749-6-19-23 ◽

2017 ◽

Vol 749 (6) ◽

pp. 19-23

Author(s):

M.E. PILECKIJ ◽

◽

I.V. DIDRIKH ◽

A.F. ZUBKOV ◽

К.A. АNDRIANOV ◽

...

Keyword(s):

Jet Injection ◽

Injection Method ◽

Mineral Mixture

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Rigid polyurethane (PUR) foam produced by the press injection method

10.3403/bs6586 ◽

2015 ◽

Keyword(s):

Injection Method ◽

The Press

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MSHE-PWM Control of Modular Multilevel Direct Current Transmission System

The Open Electrical & Electronic Engineering Journal ◽

10.2174/1874129001509010553 ◽

2015 ◽

Vol 9 (1) ◽

pp. 553-559

Author(s):

HU Xin-xin ◽

Chen Chun-lan

Keyword(s):

Pulse Width Modulation ◽

Reactive Power ◽

Balance Control ◽

Electric Energy ◽

Access Point ◽

Experimental Result ◽

Switching Frequency ◽

Pwm Control ◽

Harmonic Elimination

In order to optimize the electric energy quality of HVDC access point, a modular multilevel selective harmonic elimination pulse-width modulation (MSHE-PWM) method is proposed. On the basis of keeping the minimum action frequency of the power device, MSHE-PWM method can meet the requirement for accurately eliminating low-order harmonics in the output PWM waveform. Firstly, establish the basic mathematical model of MMC topology and point out the voltage balance control principle of single modules; then, analyze offline gaining principle and realization way of MSHEPWM switching angle; finally, verify MSHE-PWM control performance on the basis of MMC reactive power compensation experimental prototype. The experimental result shows that the proposed MSHE-PWM method can meet such performance indexes as low switching frequency and no lower-order harmonics, and has verified the feasibility and effectiveness thereof for optimizing the electric energy quality of HVDC access point.

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Study on Selective Leakage Protection System of Mine High Voltage Grid Based on Harmonic Phase Comparison

The Open Electrical & Electronic Engineering Journal ◽

10.2174/1874129001509010253 ◽

2015 ◽

Vol 9 (1) ◽

pp. 253-262

Author(s):

Liu Zhongfu ◽

Zhang Junxing ◽

Shi Lixin ◽

Yang Yaning

Keyword(s):

High Voltage ◽

Power Supply ◽

Power Supply System ◽

Supply System ◽

Neutral Point ◽

Arc Suppression Coil ◽

Zero Sequence ◽

Harmonic Extraction ◽

Power Direction ◽

The Stability

As for the wide application of arc suppression coil to the grounding in neutral point of mine high voltage grid, grid leakage fault rules and harmonic characteristics of the neutral point grounding system through arc suppression coil are analyzed, the selective leakage protection program “zero-sequence voltage starts, fifth harmonics of grid zerosequence voltage and zero-sequence current are extracted for phase comparison” is proposed, and corresponding fifth harmonic extraction circuit and power direction discrimination circuit are designed. The experimental results show that the protective principle applies not only to the neutral point insulated power supply system, but also to the power supply system in which neutral point passes arc suppression coil, which can solve selective leakage protection problems under different neutral grounding ways, improving the reliability of selective leakage and guaranteeing the stability of the action value.

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Study of Injection Method for Maximizing Oil-Cooling Performance of Electric Vehicle Motor with Hairpin Winding

Energies ◽

10.3390/en14030747 ◽

2021 ◽

Vol 14 (3) ◽

pp. 747

Author(s):

Taewook Ha ◽

Dong Kyu Kim

Keyword(s):

Electric Vehicle ◽

Flow Rate ◽

Film Formation ◽

Formation Rate ◽

Cooling Performance ◽

Oil Film ◽

Injection Method ◽

Cooling Method ◽

Oil Flow ◽

Oil Injection

The oil injection method was studied to maximize the cooling performance of an electric vehicle motor with a hairpin winding. The cooling performance of the motor using the oil cooling method is proportional to the contact area of the oil and the coil. A numerical analysis was conducted to examine the effect of the spray nozzle type on the oil flow. The dripping nozzle forms the thickest oil film on the coil, making it the most effective for cooling of hairpin-type motors. Subsequently, an experimental study was conducted to optimize the nozzle diameter and number of nozzles. When the inlet diameter and number was 6.35 mm and 6, the oil film formation rate was 53%, yielding the most uniform oil film. Next, an experiment was performed to investigate the effects of the oil temperature and flow rate on the oil flow. The oil film formation rate was the highest (83%) when the oil temperature was 40 °C and the flow rate was 6 LPM.

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