کاهش هزینه‏‌های مرتبط با موجودی از مهم‌ترین استراتژی‌‏های هر بنگاه اقتصادی برای بقا و سوددهی در شرایط رقابتی امروزی است. این راستا مدل‏‌های کلاسیک هزینه‏‌ها مطرح شده‌اند؛ اما کنار مزایای فراوان دارای فرضیه‌های محدودکننده‌ای هستند. پژوهش، یک زنجیره سه­‌سطحی لجستیکی شامل تولیدکننده، توزیع‌‏کننده خرده‏‌فروش نظر گرفته می‏‌شود مسئله بهینه‌سازی مدل توزیع‌کننده موردبررسی قرار می‏‌گیرد. موردنظر، توزیع‏...

Conventional Voltage Source Converters (VSC) cannot interrupt DC fault currents and DC circuit breakers are not yet commercially available for HVDC power ratings. Thus, the protection of VSC-HVDC systems is still an obstacle for the development of this technology. The features of VSC-HVDC systems make them suitable for implementing HVDC grids. Nevertheless, HVDC grids are more complex than poin...

VSC HVDC will be the most important approach for transmitting the power of large-scale offshore wind power plant in the near future. In recent literature, the feasibility of using hybrid type HVDC for offshore wind transmission has been discussed. A hybrid HVDC system has at one line commutated converter (LCC) at mainland and one voltage source converter (VSC) at offshore platform, which may in...

Existing mechanical HVDC breakers are capable of interrupting HVDC currents within several tens of milliseconds, but this is too slow to fulfill the requirements of a reliable HVDC grid. HVDC breakers based on semiconductors can easily overcome the limitations of operating speed, but generate large transfer losses, typically in the range of 30 percent of the losses of a voltage source converter...

HVDC Light is the most recent HVDC technology based on Voltage Source Converters (VSC) and extruded DC cables with power units up to 200 MW. HVDC Light converters include Insulated Gate Bipolar Transistors (IGBT’s) and operate with high frequency Pulse Width Modulation (PWM) in order to get high speed control of both active and reactive power. HVDC Light cable is a cable with insulation of extr...

HVDC transmission systems are becoming increasingly popular when compared to conventional AC transmission methods. HVDC voltage source converters (VSC) can offer advantages over traditional HVDC current source converter topologies; as such, it is expected that HVDC-VSCs will be further exploited with the growth of HVDC transmission. This paper presents the DC fault ride through capability and n...

The traditional HVDC plays an important role in the development of power grid. But the traditional HVDC cannot supply power either to entirely passive AC network or to weak AC system. In fact, an entirely passive AC network can be effectively powered through VSC-HVDC. However, the cost of investment in VSC-HVDC is amazingly high due to the limitation of power electronics technology. Based on CS...