1994 Chrysler Concorde LOOSE POWER

I Have 1994 chrysler concorde and I was driving @ about 50 mph and with no warning the car just shut off, so I glided over to the side of the road and waited about 15 minutes and the car started right up this happened 4x's the last time I pulled in the driveway and it shut off by itself to never start again! I have a factory alarm in it do you think its the alarm there is no pwer goin to the ignition or when you try to start it there is no gas smell we tested everything checked fuses someone said it was the crank shaft sensor what is you opinion?