Series resonant sinewave output filter and design methodology
AssigneeRockwell Technologies, LLC
InventorsGary L. Skibinski, Brian R. Buchholz
Life of this patent
Estimating the term…
Abstract
An apparatus to be used with a PWM VSI which is linked by voltage supply cables to either a passive or a dynamic load, the VSI providing voltages on the cables which have at least one primary harmonic component, the apparatus linked to the output terminals of the VSI and including a line inductor between each output terminal and the load and, for each cable, at least one resonant filter branch including an inductor and a capacitor linked to each of the supply lines and to a common node wherein the line inductors are chosen so as to limit filter current and the branch elements are chosen such that a resonant frequency thereof is essentially equal to the frequency of the primary harmonic component.
Claims35
An apparatus for reducing reflected line voltages on AC supply lines of an AC motor, the motor having first, second and third stator windings, each winding separately connected to an alternating voltage source by either a first, second or third supply line, the voltage source supplying high frequency voltage pulses on each supply line, the apparatus comprising:
- a current limiter positioned between the source and motor to limit current on the supply lines;
- N filter configurations, each filter configuration comprising:
- a first leg including a first voltage storage element and a first inductive element arranged in series between the first line and a common node;
- a second leg including a second voltage storage element and a second inductive element arranged in series between the second line and the common node;
- and
- a third leg including a third voltage storage element and a third inductive element arranged in series between the third line and the common node;
- wherein the common node is only linked to the legs;
- wherein inductive elements in the same filter configuration have essentially the same values and voltage storage elements in the same filter configuration have essentially the same values.
A system for reducing reflected line voltages on AC supply lines of an AC motor, the motor having first, second and third stator windings which are linked to first, second and third voltage supply lines, the first, second and third supply lines linked to separate first, second and third phases of a voltage source inverter (VSI), the system comprising:
- an apparatus comprising:
- N filter configurations, each filter configuration comprising:
- a first leg including a first voltage storage element and a first inductive element arranged in series between the VSI first phase and a common node;
- a second leg including a second voltage storage element and a second inductive element arranged in series between the VSI second phase and the common node;
- and
- a third leg including a third voltage storage element and a third inductive element arranged in series between the VSI third phase and the common node;
- the common node is only linked to the legs;
- wherein inductive elements in the same filter configuration have essentially the same values and voltage storage elements in the same filter configuration have essentially the same values.
A system for providing voltages on AC supply lines of an AC motor, the motor having first, second and third stator windings which are linked to first, second and third voltage supply lines, the system comprising:
- a transformer including first and second primary windings and at least one secondary winding, the transformer secondary windings linked to the first, second and third supply lines;
- a first three phase voltage source inverter linked to the first primary winding;
- a second three phase voltage source inverter linked to the second primary winding;
- and
- N filter configurations, each filter configuration comprising:
- a first leg including a first voltage storage element and a first inductive element arranged in series between the first line and a common node;
- a second leg including a second voltage storage element and a second inductive element arranged in series between the second line and the common node;
- and
- a third leg including a third voltage storage element and a third inductive element arranged in series between the third line and the common node;
- wherein the common node is only lined to the legs;
- wherein inductive elements in the same filter configuration have essentially the same values and voltage storage elements in the same filter configuration have essentially the same values.
A system for providing low harmonic voltages on AC supply lines of an AC motor, the motor having first, second and third stator windings which are linked to first, second and third voltage supply lines, the system comprising:
- a first voltage source inverter (VSI) including first VSI first, second and third phases;
- a second VSI including second VSI first, second and third phases;
- a first inductor set including first, second and third inductors which link the first VSI first, second and third phases to the first, second and third supply lines, respectively;
- a second inductor set including fourth, fifth and sixth inductors which link the second VSI first, second and third phases to the first, second and third supply lines, respectively;
- and
- an apparatus including N filter configurations, each filter configuration comprising:
- a first leg including a first voltage storage element and a first inductive element arranged in series between the first line and a common node;
- a second leg including a second voltage storage element and a second inductive element arranged in series between the second line and the common node;
- and
- a third leg including a third voltage storage element and a third inductive element arranged in series between the third line and the common node;
- wherein the common node is only linked to the legs;
- wherein inductive elements in the same filter configuration have essentially the same values and voltage storage elements in the same filter configuration have essentially the same values.
An apparatus for reducing reflected line voltages on AC supply lines of an AC motor, the motor having first, second and third stator windings which are linked to first, second and third voltage supply lines, the first, second and third supply lines connected to separate phases of a three phase voltage source inverter (VSI), the apparatus comprising:
- N filter configurations, each filter configuration comprising:
- a first leg including a first voltage storage element and a first inductive element arranged in series between the first line and a common node;
- a second leg including a second voltage storage element and a second inductive element arranged in series between the second line and the common node;
- and
- a third leg including a third voltage storage element and a third inductive element arranged in series between the third line and the common node;
- wherein the common node is only linked to the legs;
- wherein inductive elements in the same filter configuration have essentially the same values and voltage storage elements in the same filter configuration have essentially the same values.
Dependencies are inferred from the claim text.