JP2012019640A5

JP2012019640A5 -

Info

Publication number: JP2012019640A5
Application number: JP2010156182A
Authority: JP
Filing date: 2010-07-08
Publication date: 2013-08-22
Anticipated expiration: 2030-07-08

Description

本発明の電源回路は、
電源から負荷へ電力を供給する経路に配置され、前記経路を導通／遮断するためにオン状態とオフ状態との間で切り替わるスイッチ手段と、
前記スイッチ手段がオフ状態からオン状態へまたはオン状態からオフ状態へ切り替わるよう駆動する制御手段と
を備え、
前記制御手段は、前記スイッチ手段をオフ状態からオン状態に移行させた直後の第１期間において、前記負荷に対する突入電流のピーク値を抑制するように予め定められたパルス状の駆動信号を前記スイッチ手段に供給し、前記第１期間に続く第２期間において、前記スイッチ手段をオン状態に維持するための駆動信号を前記スイッチ手段に供給することを特徴とする。 The power supply circuit of the present invention is
Switch means disposed in a path for supplying power from a power source to a load and switching between an on state and an off state to conduct / cut off the path;
Control means for driving the switch means to switch from an off state to an on state or from an on state to an off state;
With
In the first period immediately after the switch means is shifted from the off state to the on state, the control means outputs a pulse-shaped drive signal that is predetermined to suppress a peak value of the inrush current to the load. And a drive signal for maintaining the switch means in an ON state is supplied to the switch means in a second period following the first period .

Claims

A power circuit,
Switch means disposed in a path for supplying power from a power source to a load and switching between an on state and an off state to conduct / cut off the path;
Control means for driving the switch means to switch from an off state to an on state or from an on state to an off state, and
In the first period immediately after the switch means is shifted from the off state to the on state, the control means outputs a pulse-shaped drive signal that is predetermined to suppress a peak value of the inrush current to the load. And a driving signal for maintaining the switch means in an ON state in a second period following the first period.

2. The power supply circuit according to claim 1, wherein the drive signal for maintaining the switch means in the second period is a drive signal having a constant voltage value.

The pulse-shaped drive signal supplied from the control means in the first period is a PWM signal whose on-duty ratio can be changed. The on-duty ratio of the PWM signal depends on the capacitance value of the capacitance component included in the load. The power supply circuit according to claim 1, wherein the power supply circuit is determined.

The said control means reduces the on-duty ratio of the said PWM signal, and extends the length of the said 1st period, if the capacity | capacitance value of the capacitance component with which the said load is increased, The length of the said 1st period is extended. Power supply circuit.

The pulse-shaped drive signal supplied from the control means in the first period is a PWM signal whose on-duty ratio can be changed, and the control means determines the on-duty ratio as time elapses in the first period. The power supply circuit according to claim 1, wherein the power supply circuit is increased step by step.

The control unit divides the first period into n (n is a natural number of 2 or more) periods, and an on-duty ratio of an i-th (i = 2 to n natural number) period is an (i−1) th period. 6. The power supply circuit according to claim 5, wherein the on-duty ratio of each period is determined so as to be larger than the on-duty ratio of the period.

The switch means includes
An input electrode to which a DC voltage from a power source is input;
An output electrode that outputs a DC voltage input from the input electrode;
A control electrode to which the drive signal output from the control means is input,
The power supply circuit is
A capacitor connected between the input electrode and the control electrode;
The pulse-shaped drive signal supplied from the control means in the first period is a PWM signal whose on-duty ratio can be changed,
2. The power supply circuit according to claim 1, wherein the capacity of the capacitor is set to the smallest capacity among combinations of the capacity of the capacitor capable of suppressing the inrush current and the on-duty ratio.

The pulse-shaped drive signal supplied from the control means in the first period is a PWM signal whose on-duty ratio can be changed,
The control means includes
Measuring means for measuring a capacitance value of a capacitive component included in the load;
If the capacity measured by the measuring means is relatively large, the on-duty ratio is set relatively small. If the capacity measured by the measuring means is relatively small, the on-duty ratio is set relatively large. The power supply circuit according to claim 1, further comprising setting means for performing

The setting means determines the on-duty ratio of the drive signal by multiplying the on-duty ratio corresponding to the maximum load capacity assumed in advance by the reciprocal of the capacity measured by the measuring means. The power supply circuit according to claim 8 .