【Networking power supply】HVDC applications and power supply design trends
NEW!

High Voltage Direct Current (HVDC) as the name suggests, refers to high voltage direct current power supply. Compared to the common, conventional voltages 12V, 19V, 48V and 54V, HVDC has a higher voltage range, usually over 110V, and even reaches hundreds of thousands of volts in long-distance transmissions. Why did HVDC rise again and gradually replaced many traditional AC power supply systems in recent years? What significant advantages do HVDC have?

As early as the emerging of the electric power industry in the 1880s, a “current war” that would influence the development of science and technology for the next one hundred years had broken out. The direct current power supply system led by Edison and the alternating current power supply system promoted by Europe and the Westinghouse camp competed fiercely. Finally, the alternating power supply system won and became mainstream. However, the advantages of direct current supply were not forgotten.

The electrical appliances that we use daily, such as lights, computers, mobile phones and motors, etc., mostly rely on direct current. The architecture of direct current is simpler, and its energy consumption during long-distance transmission is lower than alternating current, at only approximately 3% per 1000 kilometers. However, direct current has a major disadvantage: it cannot change voltage at will. In alternating power systems, voltages and be easily increased and decreased by using transformers designed on the basis of Faraday’s law of electromagnetic induction. However, under the technical conditions of a hundred years ago, the only way to achieve this was to supply electricity to motors and then have them regenerate the electricity.

In the last one hundred years, power electronics technology advanced rapidly, the development of active components such as semiconductors made DC voltage conversion no longer as difficult as it used to be. With the rise of energy-saving awareness, the popularization of solar power generation, the maturing of long-distance DC transmission technology, the forming of the decentralized power grid concept, and the breakthroughs in electric energy storage technology, the advantages of DC power supply systems are valued again, and are widely applied in fields such as data centers and the DC lighting systems in office buildings.

The HVDC power supply systems adopted in data centers have multiple advantages including lowering costs, saving energy and improving reliability. Since solar power generation, long-distance DC transmission power systems and battery energy storage equipment all operate with direct current. Direct connection to HVDC systems can reduce unnecessary AC-DC and DC-AC conversion nodes. Not only does this eliminate the construction cost of conversion nodes, it can also reduce the energy consumption in the conversion process. Meanwhile, the simplified system architecture also reduces the failure rate and improves the reliability of the overall system effectively.

When power supplies are applied on HVDC power supply systems, compared with traditional AC power supplies, there are significant differences in their designs. Because of the differences in their features, such as input voltage, overvoltage levels and transient voltages, their requirements for insulation distances have also changed. In addition, the selection of safety-critical components must use components that comply with DC voltage certifications. In terms of testing methods, according to IEC 62368-1 standards, a range of +20% and -15% must be selected for the testing of DC Mains. These factors must be planned and dealt with in the early stages of development to ensure system safety and reliability.

Asian Power Devices has been deeply involved in the field of network communication power supply for many years, and has developed many dual-purpose power supply products compatible with HVDC and AC input that have passed complete certifications. We have rich experiences and deep expertise in power supply applications and design in the HVDC field, and are equipped with a complete a solid team. Amid new technologies, design requirements and regulatory changes, Asian Power Devices, a trustworthy partner to its customers, continues to innovate and grow.