In-rush current controller with continuous cycle-by-cycle control
AssigneePI Electronics (Hong Kong) Limited
InventorMan Sing Tse
Life of this patent
Estimating the term…
Abstract
An in-rush current controller for a mains power rectification circuit including a fill wave rectifier and a capacitor. A serial resistor suppresses in-rush currents. The controller includes a sensing circuit that controls a pair of silicon controlled rectifiers to cyclically shunt or isolate the resistor during normal operation. Thus, power is not dissipated by the resistor and undesirable heat is not generated during normal operation. The sensing circuit responds to abrupt rises in voltage (typical of in-rush current conditions) to inhibit turn ON of the rectifiers so that the resistor is not shunted or isolated at such times.
Claims14
An in-rush current controller for controlling a current flowing into an AC mains power rectification circuit, the controller having:
- a serial resistor for limiting an in-rush current flowing into the rectification circuit, and
- a sensing circuit automatically monitoring the in-rush current flowing into the rectification circuit in each half cycle of the in-rush current flowing into the rectification circuit, and electrically isolating the serial resistor whenever, half cycle by half cycle, the in-rush current flowing into the rectification circuit is below a threshold current, the sensing circuit including a pair of silicon controlled rectifiers sequentially controlled to shunt and isolate the serial resistor in each respective current half cycle only when the in-rush current is below the threshold current during that half cycle.
An in-rush current controller for controlling a current flowing into an AC mains power rectification circuit, the controller having:
- a serial resistor for limiting an in-rush current flowing into the rectification circuit, and
- a sensing circuit automatically monitoring the in-rush current and electrically isolating the serial resistor whenever the current flowing into the rectification circuit is below a threshold current, the sensing circuit including a pair of silicon controlled rectifiers sequentially controlled to shunt and isolate the serial resistor in each respective current cycle when the in-rush current is below the threshold current, the sensing circuit responding to a rate-of-rise of an input voltage applied to the rectification circuit and electrically isolating the serial resistor only if the rate-of-rise is below a threshold rate-of-rise.
An in-rush current controller for controlling a current flowing in an AC mains power rectification circuit, the controller comprising:
- a serial resistor for limiting an in-rush current flowing into the rectification circuit,
- a sensing circuit automatically monitoring the in-rush current and electrically isolating the serial resistor whenever the current flowing into the rectification circuit is below a threshold current, the sensing circuit including a pair of silicon controlled rectifiers sequentially controlled to shunt and isolate the serial resistor in each respective current cycle when the in-rush current is below the threshold current, and
- circuit means for triggering each silicon controlled rectifier prior to each conduction cycle of the current flowing into the rectification circuit to inhibit electrical noise emission.
An in-rush current controller for controlling a current flowing into an AC mains power rectification circuit, the controller having:
- a serial resistor for limiting an in-rush current flowing into the rectification circuit in each half cycle of a current flowing into the rectification circuit, and
- a sensing circuit automatically monitoring rate-of-rise of instantaneous voltage applied to the rectification circuit and electrically isolating the serial resistor whenever the rate-of-rise is below a threshold rate-of-rise.
Dependencies are inferred from the claim text.