Analys och utveckling av LED-belysning

Sammanfattning: Modern Street Lights (MSL) has a LED-lighting that suddenly fails during use. The first part in the project is to find the cause to the failure. In addition, MSL has a new idea for a lamp post. The second part in the project is to develop an electric structure for the lamp post. An EMC test is conducted to see if the EMC Directive can be met. The process of a CE marking of the prototype is summarized in a CE guide. The analysis consists of collecting electrical data of the broken LED-lighting. The same analysis is performed on a functioning LED-lighting. The functioning LED-lighting acts as a reference in the analysis. A comparison between these shall provide a basis for detecting the cause of the accident at the broken LED-lighting.The development of a new LED-lighting is based on a preliminary study as well as the demands of MSL on the prototype. The EMC test is carried out in the electronics center at Halmstad University. The result of the analysis shows a deviation in the design and in the voltage drop of the LED-component. Burns on the LED-components indicates that the circuit has been stressed with too much current. A normal distribution shows that the LED-components of the broken LED-lighting do not have the same stability as in the functioning LED-lighting. The conclusion is that too much current has floated in the circuit.  The cause is probably made of external voltage increases. The result over developed LED-lighting proves to achieve the client's prototype requirements. The prototype does also achieve a part of the EMC requirements. A future work is to optimize the electrical design. The heat release from the resistor has to reduce. A solution is to find a CE-marked drive that matches the electrical data of the LED-luminaire. This increases the total efficiency.