A study on measurement method for transient current from lighting equipment with considering the dependence on test sites

Abstract

Recently, lighting equipment using inverter control and light emitting diode (LED) has been used in machine rooms in telecommunication centers and data centers to save energy. However, LED lighting equipment is known to generate harmful levels of electromagnetic transient disturbances (in particular, transient currents in power lines) to ICT equipment [1]. CISPR 15 [2], the international standard for electromagnetic disturbances from lighting equipment, defines a measurement method and limit level for continuous electromagnetic disturbance, but does not specify a measurement method or limit level for transient currents. We propose a measurement method to evaluate the peak level of transient currents from LED lighting equipment in a representative actual-use environment. This method, using a phase control switch, a power network impedance (PNI) compensation circuit, a PNI artificial circuit, a current probe and an oscilloscope, can avoid dependence on test sites, and enable highly reproducible measurements. We optimized the parameters of the PNI compensation circuit by circuit simulation, and the PNI artificial circuit by measurement. It was found that the proposed method enables highly reproducible measurement of transient currents from LED lighting equipment, thus avoiding dependence on test sites.