CFaulty arc: when welding machine and welding robot working , the faulty arc takes place in the circuit of power supply and disturb the power quality. meanwhile , arc with high heating energy often lead to fire accident.
Harmonic and three phase unbalance : harmonic and three phase unbalance are existed in processing steps of stamping , welding , coating , assembling. Automotive industry need have a excellent power supply to maintain the process of production . it often being at risk of being interfered by poor quality power such as unstable ,harmonic , resonance and reactive power, also make equipment overheat and communication interference.
1 Stamping : automotive industry require the electrical or thermal conductivity of beryllium copper in areas such as many alloys within the equipment such as DNC, arc plasma cutter , multi position stamping machine, all of them ceaselessly create harmonic and pulse load , which lead to unstable voltage and power factor getting-down, current distortion . Lead to stamping is not in place by over-voltage, over-current , over-current,and insufficient pressure, the phenomenon takes place in instability of the power supply system,which causing serious voltage flicker, instantaneous voltage drop and other malfunction movement , so that some equipment to stop running.
2 Welding : arc welding ,electric resistance welding etc welding methods are the mainly reason that create harmonic ,and three phase unbalance and unstable current or /and voltage.being result in welding quality do not concur with standard of quality control. In addition, the harmonic currents makes the device unable to operate normally, resulting in the increase of the neutral current, reducing the service life of the cable and destroying the cable in severe cases.
3 Coating : coating may be applied to change the surface properties of the substrate , such as adhesion,wet ability, corrosion resistance, or wear resistance . in other cases , e.g semiconductor device fabrication, the coating adds a completely new property such as a magnetic response or electrical conductivity and forms an essential part of the finished product. heating equipment makes harmonic and three phase unbalance there will be happen to decrease the power factor . As a result, equipment loss in coating process, voltage peak increase, transformer noise gets larger and load capacity decreases. Most of equipment appears malfunction or failure.it also appear the quality of coating in the surface as per the bubble, drain coating, grinding not in place, painting repetition and other malfunction. On the side of reactive consumption , its increasing causes the bus-voltage drops, and over-low voltage in heating equipment in order to reach for temperature of coating.
4 Assembling : process of assembling controlled by diode, triode, rectify, amplifier circuit devices meanwhile with small harmonic happened and accumulated. As a result, the current and voltage are distorted so that devices such as that PLC s and micro controllers in zero-crossing operation may malfunction by voltage fluctuation, leading to premature or delayed zero crossing, affecting the overall control system and the operation and accuracy of power electronic devices, so that the manipulator malfunction, damage capacitors, the temperature of the main control board increases, reducing the lifetime of electronic components.