Limitující faktory časové odezvy magnetoreologického tlumiče

Limiting factors of the response time of the magnetorheological damper

journal article in Web of Science

en

Magnetorheological dampers seem to be suitable for the adaptive car suspension systems. For proper operation of the semi-active algorithms (skyhook, groundhook), the force response of the damper must be fast enough. In this paper, the response time of the Delphi vehicle MR damper is examined and the sources of the overall force time response on the control voltage are discussed. One of the main sources of the response time seems to be electro-magnetic circuit of the MR damper. A principle of an optimal controller for reducing response of the coil’s current on the control voltage is designed. However, the measured overall force time response with fast current controller was not reduced as expected. Therefore, a FEM simulation of the magnetic circuit was made. It shows that after an optimization of the current controller, eddy currents in the coil’s core cause long time response and therefore they are the limiting factor of the response time of the MR damper. These simulations were verified by the measurements and some recommendations about improving the pistons construction are given at the end.

Magnetoretoreologické tlumiče se zdají být vhodné pro adaptivní odpružení automobilů. Pro správnou funkci semiaktivních algoritmů (Skyhook, Groundhook) musí být časová odezva síly tlumiče dostatečně rychlá. V tomto článku je zjišťována časová odezva MR tlumiče a jsou nastíněny pravděpodobné příčiny. Jednou z hlavních příčin se zdá být elektromagnetický obvod MR tlumiče. Je navržen optimální způsob řízení proudu cívkou tlumiče. I po aplikaci tohoto řízení ale nebylo dosaženo očekávané celkové doby odezvy MR tlumiče. Proto byla provedena FEM simulace magnetického obvodu, ze které vyplývá, že hlavním zdrojem dlouhé časové odezvy (pokud je použit rychlý proudový regulátor) jsou vířivé proudy.

Magnetorheological dampers seem to be suitable for the adaptive car suspension systems. For proper operation of the semi-active algorithms (skyhook, groundhook), the force response of the damper must be fast enough. In this paper, the response time of the Delphi vehicle MR damper is examined and the sources of the overall force time response on the control voltage are discussed. One of the main sources of the response time seems to be electro-magnetic circuit of the MR damper. A principle of an optimal controller for reducing response of the coil’s current on the control voltage is designed. However, the measured overall force time response with fast current controller was not reduced as expected. Therefore, a FEM simulation of the magnetic circuit was made. It shows that after an optimization of the current controller, eddy currents in the coil’s core cause long time response and therefore they are the limiting factor of the response time of the MR damper. These simulations were verified by the measurements and some recommendations about improving the pistons construction are given at the end.

Magnetorheological damper; MR; time response; pulse-width modulation; eddy current

2015

08.06.2015

IOS Press

1383-5416

47

2

541–550

9