System and method for energizing a solenoid coil for fast solenoid actuation
AssigneeCapstan Ag Systems, Inc.
InventorsKale Schrader, Duane Needham
Life of this patent
Estimating the term…
Abstract
A drive circuit for operating a solenoid includes a main switch and a charge pump circuit. The main switch is coupled in series with a coil of the solenoid. The main switch is configured to selectively enable current flow from a voltage source according to a main switching signal to translate a poppet of the solenoid between an opened position and a closed position. The charge pump circuit is coupled to the voltage source. The charge pump circuit is configured to discharge through the coil to translate the poppet from the closed position to the opened position, and to charge when the poppet is held in the opened position.
Claims27
A drive circuit for operating a solenoid, comprising:
- a main switch coupled in series with a coil of the solenoid, the main switch configured to selectively enable current flow from a voltage source according to a main switching signal to translate a poppet of the solenoid between an opened position and a closed position;
- a charge pump circuit coupled to the voltage source, the charge pump circuit configured to discharge through the coil to translate the poppet from the closed position to the opened position, and to charge when the poppet is held in at least one of the opened position and the closed position;
- and
- a flyback circuit coupled in parallel to the coil, the flyback circuit configured to be enabled when the poppet is held in the opened position, wherein the flyback circuit comprises a diode and a flyback switch coupled in series, the flyback switch configured to enable and disable the flyback circuit according to a flyback switching signal.
A method of operating a drive circuit for a solenoid, the method comprising:
- enabling discharge of a charge pump circuit coupled to a voltage source;
- enabling a first current to flow from the voltage source and the charge pump circuit through a coil of the solenoid to translate a poppet of the solenoid from a closed position to an opened position;
- modulating a second current to flow from the voltage source through the coil to hold the poppet in the opened position, wherein modulating the second current comprises pulse-width modulating the second current to a high-frequency pulse-width modulated (PWM) current signal to hold the poppet in the opened position;
- charging the charge pump circuit after the poppet translates to the opened position;
- and
- coupling a flyback circuit in parallel with the coil during the modulating of the second current, wherein coupling the flyback circuit in parallel with the coil comprises commutating a flyback switch to couple a low-forward voltage diode in parallel with the coil when the high-frequency PWM current signal is supplied to the coil to hold the poppet in the opened position.
A method of operating a drive circuit for a solenoid, the method comprising:
- enabling discharge of a charge pump circuit coupled to a voltage source;
- enabling a first current to flow from the voltage source and the charge pump circuit through a coil of the solenoid to translate a poppet of the solenoid from a closed position to an opened position, wherein enabling the first current to flow comprises:
- applying a coil voltage from the voltage source at a first time;
- and
- applying a capacitor voltage from the charge pump circuit at a second time after the first time;
- modulating a second current to flow from the voltage source through the coil to hold the poppet in the opened position;
- and
- charging the charge pump circuit after the poppet translates to the opened position.
A drive circuit for operating a solenoid, the drive circuit comprising:
- a charge pump circuit coupled to a voltage source;
- and
- a main switch coupled in series with a coil of the solenoid;
- wherein the charge pump circuit and the main switch are configured to enable a first current to flow from the voltage source and the charge pump circuit through the coil to translate a poppet of the solenoid from a closed position to an opened position;
- wherein, to enable the first current to flow, the charge pump circuit and the main switch are configured to:
- apply a coil voltage from the voltage source at a first time;
- and
- apply a capacitor voltage from the charge pump circuit at a second time after the first time;
- wherein the main switch is configured to modulate a second current to flow from the voltage source through the coil to hold the poppet in the opened position;
- and
- wherein the charge pump circuit is configured to charge after the poppet translates to the opened position.
Dependencies are inferred from the claim text.