Electric power supply of heater elements of electric propulsion thruster by regulated alternating current

Using of electric propulsion thrusters for space-craft’s orbit correction allow decreasing mass of electric propulsion system due to reduced propellant mass. At the moment using direct current in electric power supply of electric propulsion thruster’s heater elements is due to simple measuring and stabilization. On the transformer output has the low-voltage power rectifier because galvanic isolation power supply is required. Using the low-voltage power rectifier is significantly increasing power loss. In addition, diode’s slow response increases the noise level of transformer. Electric power supply by regulated alternating current improving dimensions, mass and electric power characteristics of power processing unit is used. Cardinal problem in work with regulated alternating current is changing current waveform which depends on load resistance, supply voltage and length of cables. These changes will make measuring root-mean-square value of current difficult as well as current stabilization. We have several ways of solution of these problems: sensing unit of root-mean-square value of current, output L-filter, input regulator of DC current and unregulated output inverter. Most long-term way of solution is using sensing unit of root-mean-square value of current. But at the moment effective using is input regulator of DC current with unregulated output inverter and L-filter. That design of power supply ensuring fixed waveform of output current independent of input voltage and load resistance. L-filter circuit removes influence of cables. In this paper SPICE-model of electric power supply (operating on alternating current) of cathode heater is presented. Also time diagrams of operating SPICE-model limit values of voltage supply, load resistance and inductance of cables are presented. Submitted data allow achieving practical realization of this power supply. Using of electric power supply of heater elements of electric propulsion thruster by regulated alternating current is long-term aim, which improving mass and electric power characteristics of electric propulsion system.