Impact of harmonics on electricity consumption 

in the automobile and shipbuilding industries

        Under the background of worldwide promoting "energy conservation and emission reduction”, the demand for energy conservation in manufacturing companies such as automobiles and ships is deepening. While energy-saving equipment is widely used in the distribution system, it generates a large amount of harmonic pollution, bringing challenges such as power loss and safety hazards. The harmonic control solution provided by Xixing Technology can effectively solve the power quality problems in the automobile, shipbuilding and other manufacturing industries, and create a green, healthy, safe and stable power consumption environment.

Where do harmonics come from in the automotive 

and shipbuilding industries?

        The main sources of harmonic power pollution in the automotive and shipbuilding industries are nonlinear loads such as welders, DC motors, and frequency converters.

        Spot welders are typical single-phase impact loads and harmonic sources. Since the welding machine uses the principle of two-phase short circuits, it will cause a large current imbalance, and the current harmonic distortion rate will generally reach about 10~30%, and the harmonic frequency is mainly 5~13 times.

        DC motors are typical harmonic sources and impact loads. Harmonic current accounts for about 30% of the total current of the equipment. The harmonic frequency changes according to the change of system load, and the harmonic frequency is mainly 5~7 times.

        The circuit of the frequency converter is generally composed of four parts: rectification, intermediate DC link, inversion and control. The current distortion rate generally reaches about 30~50%, and the harmonic frequency is mainly 5~7 times.

    Pain points of harmonics in automobile and shipbuilding industries

         The existence of harmonic currents will cause problems such as poor welding quality, false welding, leaking welding, and wrong welding, which will make the product quality substandard.

        Harmonics will increase equipment loss in the paint shop, causing malfunctions of equipment such as painting, coating, and transportation, resulting in uneven coating, inadequate transportation, bubbles on the coating surface, missing coating, inadequate grinding, and repeated coating.

         Harmonics will cause PLC, single-chip microcomputer and other equipment in the zero-crossing state to malfunction due to abnormal voltage, resulting in early or delayed zero crossing, thereby affecting the control of the entire instruction. At the same time, it will also affect the operation and accuracy of power electronic equipment, resulting in operational errors.

         Comprehensive management solutions for automobile and shipbuilding industries

Solutions of harmonics in automobile and shipbuilding industries

        EasyPQ-APF series active filters of Xixing Technology can manage 2-50 harmonics, and the harmonic filtering rate of low-order harmonics (harmonics within 13th order) can reach more than 95%. The harmonics generated by the automobile and shipbuilding industries are mainly 5th and 7th.

    In response to the harmonic problems in this industry, the EasyPQ-APF series active filters can effectively control harmonics and adjust the three-phase current imbalance, comprehensively improve the system power quality, and ensure the safety of users' electricity use.