The invention relates to a
direct current energizing method. The following steps are adopted: in a traditional
direct current power supply
system composed of a three-phase
alternating current synchronous generator, and / or a three-phase
transformer, and a three-phase
rectifier, a
alternating current synchronous generator of more than three phases and a
rectifier which is matched with the
alternating current synchronous generator in terms of a same
phase number are adopted to carry out replacement and combine into an energy saving type
direct current system. Through the adoption of the method of the invention, a line
voltage loss of 15.8% at most in an existing three-phase power
system can be reduced and even eliminated in theory, so that as for the apparatus adopting the method, the direct
current voltage of the apparatus is higher than the direct
current voltage of a traditional set of three-phase alternating current power generating added with the
rectifier. According to the direct current energizing method, the system output power has a
gain of a same degree, and the direct current
power output by the rectifier is at least 10% higher than the direct current
power output by the traditional rectifier. An electrical loss reduction value of the synchronous generator or the
transformer is no less than 5%; therefore, the set is advantageous by being highly efficient and energy saving. An added cost proportion of the set is less than power and efficiency growing rate, and substantial technical progress and good
economic benefits are achieved.