PULSE FORM OF MAGNETRON ANODE CURRENT BASED DETERMINATION OF MICROWAVE POWER TRANSFERRED TO REACTOR

Abstract

An important task in designing  microwave industrial plants  is to determine actual power  going into a process  reactor.  A part  of magnetron power  reflects  from  the  microwave reactor  into  generator due  to  the  processed  material property changes. It results  from  dielectric  property changes,  due  to changes  of temperature, humidity,  variation  of boundary conditions in the reactor  when  moving  the product. Moreover,  the reflected  wave significantly  changes the  magnetron regime  of  operation. The article  shows  that  the  power  transferred to  the  processed  product can be determined based  on changes in the  current  pulse  form  when  using  a classic power  supply (high-voltage  transformer and  a voltage  doubling circuit) and  power  supply  with invertor.  Also it is possible  to estimate the mutual influence magnetrons on each other  in microwave installations with multi  generator scheme. The difference in the  operation of the  classic power  supply  and  inverted power  supply  leads  to necessity  for different power  determining algorithms. Microwave  power  in the  load  determined experimentally coincides  with  the  microwave power  calculated by the developed method, which confirms the reasoning of the algorithm used.