US 5,351,181 A · Low cost active power line conditioner

Abstract

A novel active power line conditioner is disclosed. The apparatus includes a parallel inverter, with a dc-link, coupled to an output line. The parallel inverter is controlled by a parallel inverter controller which forces the parallel inverter to act as a variable capacitor or inductor. The parallel inverter controller identifies and feeds-forward a desired phase shift value between an active power line conditioner voltage output signal and an active power line conditioner voltage input signal. Utilization of the desired phase shift value results in voltage control of the dc-link of the parallel inverter. The parallel inverter controller also produces a tuning capacitance current reference signal which reduces voltage magnitude errors of the output voltage.

Claims18

Dependent claims

An active power line conditioner comprising:

an input node connected to an input line including a series inductor;
an output node connected to an output line;
a parallel inverter coupled to said output node, said parallel inverter including a dc-link;
and
a parallel inverter controller coupled to said input node, said output node, and said parallel inverter, said parallel inverter controller forcing said parallel inverter to act as a variable capacitor, said parallel inverter controller including
means for generating a desired phase shift value between an active power line conditioner voltage output signal and an active power line conditioner voltage input signal, said desired phase shift resulting in voltage control of said dc-link, and
means for producing a tuning capacitance current reference signal to reduce voltage magnitude errors of said output voltage.

4 more elements

A method of operating an active power line conditioner of the type including an input node coupled to an input line including a series inductor, a parallel inverter coupled to an output node connected to an output line, said parallel inverter including a dc-link, said active power line conditioner further including a parallel inverter controller coupled to said input node and said parallel inverter, said parallel inverter of said active power line conditioner performing the following steps:

generating a desired phase shift value between an active power line conditioner voltage output signal and an active power line conditioner voltage input signal, said desired phase shift resulting in voltage control of said dc-link, and
producing a tuning capacitance current reference signal to reduce voltage magnitude errors of said output voltage.

Dependencies are inferred from the claim text.

Low cost active power line conditioner

Life of this patent

Low cost active power line conditioner

Life of this patent

Abstract

Claims18