Welding-type power source with integrated open-circuit voltage controller
AssigneeIllinois Tool Works Inc.
InventorsQuinn W. Schartner, Thomas A. Bunker
Life of this patent
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Abstract
A welding-type system and method for operating a welding-type system is disclosed. The system includes a switched power delivery circuit connected to deliver power to output terminals and an open-circuit voltage (OCV) control circuit configured to adjust an operational state of the switched power delivery circuit. A controller is included that is configured to monitor the output terminals to identify an open circuit condition and selectively engage the OCV control circuit to adjust the operational state of the switched power delivery circuit to reduce a voltage of the output power delivered to the output terminals during the open circuit condition.
Claims19
A welding-type power source comprising:
- an inverter configured to deliver welding-type power to output terminals of the welding-type power source;
- a controller configured to:
- determine a connection of a voltage sensing wire feeder connected to the output terminals;
- monitor conditions of the welding-type power at the output terminals to determine an open-circuit condition;
- and
- control the inverter to deliver a reduced open-circuit voltage to the output terminals in response to determining that the voltage sensing wire feeder is connected to the output terminals and determining the open-circuit condition, wherein the controller is configured to adjust a duty cycle of the inverter to deliver the reduced open-circuit voltage.
A method of operating a welding-type power source, comprising:
- controlling an inverter to deliver a welding-type power to output terminals of the welding-type power source;
- determining connection of a voltage sensing wire feeder connected to the output terminals;
- monitoring conditions of the welding-type power at the output terminals to determine an open-circuit condition;
- comparing a voltage at the output terminals to a predetermined voltage window;
- engaging a failsafe lockout if the voltage is outside the predetermined voltage window for a predetermined time interval;
- and
- controlling the inverter to deliver a reduced open-circuit voltage to the output terminals in response to determining that the voltage sensing wire feeder is connected to the output terminals and determining the open-circuit condition.
A welding-type power source comprising:
- an inverter configured to deliver welding-type power to output terminals of the welding-type power source;
- a controller configured to:
- determine a connection of a voltage sensing wire feeder connected to the output terminals;
- monitor conditions of the welding-type power at the output terminals to determine an open-circuit condition;
- and
- control the inverter to deliver a reduced open-circuit voltage to the output terminals in response to determining that the voltage sensing wire feeder is connected to the output terminals and determining the open-circuit condition;
- and
- a resistor-capacitor (RC) filter between the output terminals having a capacitance of at least:
- C
- ≥
- (
- π
- ·
- f
- S
- )
-
- (
- Tp
- m
-
-
- i
-
-
- n
- )
- 2
-
- (
- V
- S
- -
- 10
- )
- 2
- 11
-
- ,
-
- 250
- ;
- where fs is a switching frequency of the inverter, Tpmin is a minimum achievable pulse width on time, and Vs is a non-reduced voltage of a transformer secondary of a transformer connected to the inverter.
Dependencies are inferred from the claim text.