US 2017/0373609 A1 · High-Frequency Variable Load Inverter and Related Techniques

Abstract

Inverter systems, circuits and associated control techniques for providing efficient delivery of high-frequency (HF) power and radio-frequency (RF) power into variable load impedances while maintaining resistive/inductive loading of the constituent inverters for zero voltage switching (ZVS) are described. The inverter architecture and associated control techniques for providing efficient delivery of HF into variable load impedances includes a first inverter having an output coupled to an input of an immittance converter. An output of the immittance converter is coupled to a second inverter. The second inverter maybe either serially or parallel coupled between the output of the immittance converter and a load.

Claims24

Dependent claims

An inverter system having an output with the output configured to be coupled a load, the inverter system comprising:

a first inverter having an output adapted to be directly connected to the load wherein the first inverter is coupled such that its output is coupled in series or in parallel with the load.
an immittance converter having first and second ports;
and
a second inverter having an output coupled to the load through said immittance converter and wherein said immittance converter is configured such one of said first and second immittance converter ports is coupled in parallel or series with the load;
and
a controller coupled to provide control signals to said first and second inverters such that a capacitive susceptive portion of a load current is substantially provided by said second inverter via said immittance converter, and an inductive susceptive portion of load current is substantially provided by said first inverter.

3 more elements

In an inverter system having a first [Inverter A] directly coupled to a load with an output in parallel or in series with the load and a second inverter [Inverter B] coupled to the load through an immittance converter with one port of the immittance converter in parallel or series with the load, a method of operating the inverter system comprising:

(a) setting an in-phase component of a voltage command (VAI) to the first inverter [Inverter A] to achieve a desired radio frequency (RF) power level at an RF output of the second inverter [Inverter B];
(b) setting a quadrature-phase component of a voltage command (VAQ) to the first inverter [Inverter A] to a first reference value;
(c) setting a quadrature-phase component of a voltage command (VBQ) to the second inverter [Inverter B] such that the second inverter [Inverter B] drives a capacitive component of the first inverter [Inverter A] loading to substantially zero, and wherein the quadrature-phase component of a voltage command (VBQ) to the second inverter becomes zero when the load is inductive;
and
(d) setting an in-phase component of a voltage command (VBI) to the second inverter (Inverter B) such that the second inverter [Inverter B] delivers a real component of an output power which is within the voltage rating of second inverter [Inverter B] while maintaining an in-phase current sourced by first inverter [Inverter A] to be zero or positive.

2 more elements

Dependencies are inferred from the claim text.

High-Frequency Variable Load Inverter and Related Techniques

Life of this patent

High-Frequency Variable Load Inverter and Related Techniques

Life of this patent

Abstract

Claims24