For a low end inverter you could use Fujitsu's Microcontroller which has 8 channel 10 Bit ADC, PWM outputs and 16K flash. the part number for this is MB89F202 and the software i.e Softune comes free downloadable with in built C- compiler.
For implementing space vector methodology you need to look into other controller of Fujitsu which has inbuilt deadtime adjustment and also which could generate the required 6 PWMs output.
You could look at
www.fmal.fujitsu.com for more information or write to me.