JPH0467728A - Online maintenance circuit for redundant power supply - Google Patents

Abstract

PURPOSE:To eliminate butting diodes without causing an excessive charging current flow through an internal smoothing diode by providing a switch circuit(SW) for producing the voltage at a voltage detecting terminal as a reference voltage prior to connection of a connection designating terminal and producing a predetermined reference voltage (Vref) after connection of the connection designating terminal. CONSTITUTION:Under a state where a power supply CV is partially inserted into a system power supply line, a transistor Q is turned OFF and an error amplifier A has the voltage at a voltage detecting terminal P3 as a reference voltage. When the inserting work is proceeded furthermore, the power supply CV is connected completely with the system power supply line. Since a connection designating terminal P4 is connected with system side voltage, the transistor Q is turned ON. Consequently, the error amplifier A has a reference voltage Vref and the voltage at an output terminal P5 is stabilized based on the reference voltage Vref.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a redundant power supply capable of online maintenance, suitable for use in an electronic device in which a plurality of power supply devices are connected in parallel.

<Prior Art> FIG. 4 is a configuration diagram illustrating a conventional redundant power supply device. In the figure, a power supply card 10 is connected to a system power line 30 via a butt diode 20.

In such a device, there are applications in which it is necessary to insert and remove the power supply card 10 while the line is live (while the system is operating). In this case, when inserting the power card 10 into the system power line 30, a butt diode is installed to prevent excessive charging current from flowing into the output smoothing capacitor of the power card 10 from the system power line 30 side and burning out the connector. 20 was placed in series with the output of the power supply card 10.

<Problems to be Solved by the Invention> However, there is a problem in that the output voltage of the power supply card 10 drops due to the butt diode 20, increasing loss, making it impossible to obtain high efficiency, and increasing heat generation.

The present invention has solved these problems, and an object of the present invention is to provide an online maintenance circuit for a redundant power supply that achieves high output efficiency and generates little heat.

<Means for solving the problem> The first invention to achieve such an object is an input terminal (P
$R (CV
), and is connected to the relevant output terminal and the relevant common terminal, and is connected to the relevant output terminal, the voltage detection terminal (P3), and the connection instruction terminal (P4) in common to the load side circuit. A redundant power supply in which a plurality of power supplies are commonly connected to the output terminal and the common terminal to supply an output voltage has the following configuration.

That is, it connects the power supply and the load side circuit,
a connector to which the connection instruction terminal and output terminal are connected after the input terminal, voltage detection terminal, and common terminal are connected; an error amplifier (A) that stabilizes the voltage of the output terminal to a reference voltage; and the error amplifier (A) that stabilizes the voltage of the output terminal to a reference voltage. Switching times N for setting the reference voltage of the amplifier to the voltage of the voltage detection terminal when the voltage detection terminal is connected and before the connection instruction terminal is connected, and to a predetermined reference voltage (Vref) after the connection instruction terminal is connected.
(SW).

The second invention that achieves such an object is related to a case with a remote sense, and connects a power supply (CV) and a load side circuit, and the input terminal and the remote terminal (P7, P8) are connected to each other. A connector to which the output terminal and common terminal are connected after being connected, and a t of the output terminal.
[The voltage of the remote voltage detection terminal and the predetermined reference voltage (
a remote error amplifier (A0) that stabilizes the voltage at the output terminal to be equal to the voltage at the remote voltage detection terminal (A0); and a temporary error amplifier (A0) that stabilizes the voltage at the output terminal to the voltage at the remote voltage detection terminal.
1), and a switch that makes the error amplifier for controlling the power supply unit a temporary error amplifier when the remote voltage detection terminal is connected and before the connection of the direct output terminal, and a remote error amplifier after the output terminal is connected. It is characterized by comprising a circuit (SW).

For Kusaku Each component of the first invention operates as follows.

The connector has a structure in which the voltage detection terminal etc. are connected before the voltage detection terminal/output terminal. The switch circuit detects the connection state of the connector and switches the reference voltage of the error amplifier. The error amplifier increases the output voltage of the power supply to the system r8 voltage when only the voltage detection terminal etc. are connected, and prevents the generation of rush current when the output terminal is connected. After the output terminal is connected, the output voltage is stabilized by the error amplifier circuit.

The constituent elements of the second invention have the following functions.

The connector has a structure in which the remote terminal etc. are connected before the output terminal etc. The switch circuit detects the connection state of the connector and switches the error amplifier. The temporary error amplifier increases the output voltage of the power supply to the system voltage (IllI voltage) when only the remote voltage detection terminal etc. is connected, and prevents an inrush current from occurring when the output terminal is connected.

After the output terminal is connected, the output voltage is stabilized by a remote error amplifier.

<Example> The present invention will be explained below using the drawings.

FIG. 1 is a configuration block diagram showing an embodiment of the first invention, and shows a case without remote sensing. In the figure, a power source C2 is, for example, an AC-DC converter, which converts commercial AC power AC supplied from input terminals pi and P2 into a predetermined DC voltage and supplies it to an output terminal P5 and a common terminal P6. Note that the power supply CV may be a DC-DC converter by supplying a DC voltage such as 24 V from the input terminals Pi and P2, and the power supply CV may be connected in parallel with other power supply CVs via a system power line (not shown). There is.

In the load side circuit, it is connected to the output terminal P5 and the common terminal P6. In addition, voltage detection terminal P3 and connection instruction terminal P
4 is connected to the output terminal P5, and the system outputs the other power source C (which is at lII'S pressure).

FIG. 2 is an explanatory diagram of the pins of the connector. The connector connects the electric terminals 'Jji, Cv and the load side circuit on the system side. Input terminal P1. P2, voltage detection terminal P
3 and common terminal P6 pin length is connection instruction terminal 24
The output terminal P5 is longer than the pin length of the output terminal P5, and the latter terminal is connected after the former terminal is connected, realizing a so-called signal connection.

Returning to FIG. 1 again, the error amplifier A has a negative terminal connected to an output terminal P5, and a positive terminal connected to a voltage detection terminal P3 via a resistor R1. The output signal of error amplifier A is used to control the output voltage of power supply CV. The transistor Q constituting the switch circuit SW has its collector terminal connected to the positive terminal of the error amplifier A via the reference voltage source V ref, and its emitter terminal grounded.

The voltage of the connection instruction terminal P4 is applied to the base terminal of the transistor Q via the voltage dividing resistors R2 and R3.

The operation of the device configured in this manner will be described next. When power supply C■ is partially inserted into the system power supply line, input terminal P1. P2, voltage detection terminal P3 and common terminal P
6 is connected to the load side circuit, and the connection instruction terminal P4 and output terminal P5 are open. Therefore, the transistor Q is turned off and the reference voltage of the error amplifier A becomes the voltage detection terminal P3. Therefore, the voltage at the output terminal P5 is equal to that at the voltage detection terminal 23.

If the insertion operation is continued further, the power supply c■ will be connected to all system power lines. Since the connection instruction terminal P4 is connected to the system l1lIS pressure, the transistor Q is turned on. Therefore, the reference voltage of error amplifier A is the standard; voltage V
ref, and the voltage of the output terminal P5 is the reference voltage V r
It is stabilized based on ef.

FIG. 3 is a configuration block diagram showing an embodiment of the second invention, and shows a case where remote sensing is provided. Power supply C■
The configuration is the same as in FIG. The load side circuit is connected to the output terminal 25 and the common terminal 26, and has a remote voltage detection terminal 27 and a remote common terminal 28,
A voltage from the system side is applied to these remote terminals.

Use a connector with at least six terminals similar to the one in Figure 2, with the pin lengths of input terminals Pi, P2, remote voltage detection terminal P7, and remote common terminal P8 being the same as those of output terminal P5 and common terminal P6. The latter terminal is connected after the former terminal is connected.

Note that the remote common terminal P8 is directly grounded, but the common terminal P6 is grounded via a resistor R4.

The remote error amplifier AO is connected to the negative terminal or the remote voltage detection terminal P7, and is connected to the voltage dividing resistors R5 and R6.
is connected to. The positive terminal is connected to the reference voltage source V ref via a resistor R7, and the output terminal is connected to the voltage control terminal of the power supply CV via a resistor R8, and this output terminal voltage is referred to as a remote stabilized voltage 0. In the temporary error amplifier A1, the output terminal P5 is connected to the negative terminal, and the voltage v2 of the voltage dividing resistor R6 is applied to the positive terminal. This pressure v2 is selected so as to satisfy the following relationship.

Vref-Vi → -0 (1) "Rated current of connector" / [Wiring resistance] > Vref-V
i(2) Let the output voltage of the temporary error amplifier A1 be Vr. The collector terminal of the transistor Q of the switch circuit SW is connected to the positive terminal of the remote error amplifier AO, and the emitter terminal is grounded. A voltage Vr is applied to the base terminal via voltage dividing resistors R9 and R10. The base-emitter voltage BE of the transistor Q satisfies the following relationship with respect to the control voltage P14H of the power supply C during normal operation.

■PWH''Vi (3) The output voltage Vr of the provisional error amplifier A1 is matched with the output voltage ■0 of the remote error amplifier AO via the guide D1, and becomes the control voltage ■□1.

The operation of the device configured in this manner will be described next. When the power supply CV is partially inserted, the input terminals Pi, P2 and the remote terminal P7. P8 is in the connected state, and the output terminal P5
and common terminal P6 are in an oven state. Temporary error amplifier A1 has a voltage between output terminal P5 and remote common terminal P8 (-common terminal P6) or remote terminal P7.
The output voltage vr is outputted so as to be approximately equal to the voltage between P8.

Since Vr>VBE, the transistor Q is turned on and the output voltage 0 of the remote error amplifier AO becomes a low voltage.

= When the aCV is fully inserted, the remote voltage test terminal P7 voltage and the output terminal R5 voltage are almost equal,
Since the voltage Vr becomes a low voltage, the voltage Vr and the control voltages V, 1 and 1 are separated. Also, since Vr is V8F, transistor Q is turned off and remote error amplifier AO is connected to remote terminal P7. Increase the voltage between P8 # and voltage source V
It is controlled to be equal to ref.

In addition, for redundancy Toa, when sharing the load current at a predetermined ratio between the operated power supplies, which is called sharing, a parallel operation control circuit can also be installed on the control voltage VPWH line. .

In the above embodiment, a transistor Q is used as the switch circuit SW, but the present invention is not limited to this, and an equivalent device may be used when connecting the power supply card to the system power line. Since the output voltage is controlled to be the same as the system voltage, excessive charging current does not flow to the smoothing diode inside the power supply, eliminating the need for a butt diode, resulting in high output efficiency and low heat generation. A redundant power supply device can be realized.

Furthermore, according to the second invention, since the remote terminals P7P8 are used, reverse charging current of the smoothing capacitor can be prevented without increasing the number of pins of the connector.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the first invention;
FIG. 2 is an explanatory diagram of the pins of the connector, and FIG. 3 is a block diagram of the structure of the second invention, without showing an embodiment thereof. FIG. 4 is an explanatory diagram of a conventional device. C■...Power supply, A, AO, AI...Error amplifier, S
W...Switch circuit, Pl, R2...Input terminal, R3
... Voltage detection terminal, R4 ... Connection instruction terminal, R5.
...Output end As explained above, the first and second inventions provide a second output terminal. Hi-no diagram that is different from plan

Claims (2)

[Claims] (1) It has multiple power sources (CV) that convert the power sent from the input terminals (P1, P2) to a predetermined voltage and supply them to the output terminal (P5) and the common terminal (P6). The plurality of power supplies are commonly connected to the output terminal and the common terminal to the load side circuit where the output terminal, voltage detection terminal (P3), and connection instruction terminal (P4) are connected in common. A redundant power supply that connects the power supply and a load-side circuit, wherein the connection instruction terminal and the output terminal are connected after the input terminal, voltage detection terminal, and common terminal are connected. a connector to be connected; an error amplifier (A) that stabilizes the voltage of the output terminal to a reference voltage; and a reference voltage of the error amplifier that is connected to the voltage detection terminal and before the connection instruction terminal is connected. An online maintenance circuit for a redundant power supply, comprising: a switch circuit (SW) that sets the voltage at a voltage detection terminal to a predetermined reference voltage (Vref) after connection of the connection instruction terminal. (2) It has multiple power sources (CV) that convert the power sent from the input terminals (P1, P2) to a predetermined voltage and supply them to the output terminal (P5) and the common terminal (P6). At the same time, the plurality of power supplies are commonly connected to the output terminal and common terminal to supply output voltage to a load side circuit having a remote voltage detection terminal (P7) and a remote common terminal (P8). A redundant power supply comprising: a connector for connecting the power supply and a load-side circuit, to which the output terminal and common terminal are connected after the input terminal and remote terminals (P7, P8) are connected; a remote error amplifier (A0) that stabilizes the voltage at the output terminal so that the voltage at the remote voltage detection terminal is equal to a predetermined reference voltage (Vref); A provisional error amplifier (A1) stabilized at An online maintenance circuit for a redundant power supply, comprising: a switch circuit (SW) serving as a remote error amplifier;