JPH06133454A - Protecting method for insertion and removal of load - Google Patents

Abstract

PURPOSE:To shorten the time of voltage drop by making the total capacitance on the side of a load constant without increasing the capacity of a power supply package regardless of the number of mounted packages in an apparatus wherein there is a power supply system in which multiple load packages are connected to power supply lines and load packages are inserted and removed during the operation. CONSTITUTION:A plurality of branched power supply lines (a) branched from a power supply package 3 having a fixed capacitor 13 at the output part in parallel are connected to a plurality of load packages 11-1n. The packages are inserted and removed under the state wherein branched power sources are supplied in the protecting method for insertion and removal of a load. For this method, a detecting means 1 for detecting the inserting and removing state of the packages, a variable capacitor 4, which is connected to the power supply package in parallel, and a control means 2, which varies the capacitance of the variable capacitor, are provided. When the detecting means 1 detects the removal of the load package, the control means 2 is operated, and the capacitance of the variable capacitor 4 is increased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a load insertion / removal protection system for holding a capacity of a power supply line constant when a plurality of load packages connected in parallel to a power supply line are inserted / removed.

[0002]

2. Description of the Related Art Conventionally, a load insertion / removal protection system of this type will be described with reference to the configuration diagram of FIG. 3 and the explanatory diagram showing the changing state of the capacitance of the power supply line of FIG.

Now, n load packages 11, 12 to 1n which can be inserted into and removed from the power supply line of the power supply package 3 are connected. A fixed capacitor 13 is connected to the power supply package 3 between the power supply voltages VB and G. In the load packages 11 to 1n, the capacitors 21 to 2n are connected to the power supply terminal portions of the circuit bodies 31 to 3n. Now there are 10 load packages, and the total capacitance is about 21μ as shown in Fig. 4.
If it is F, the total capacitance will decrease as the number of connected packages is reduced, and if there are only two load packages,
The capacitor 13 occupies the most part and becomes about 13 μF.

Next, the operation of inserting and removing the load package when the power supply line is active will be described. As described above, in a configuration in which a plurality of load packages can be connected to the power supply line from the power supply package 3 in general, when a certain package is inserted (connected), each package is generally provided for noise removal of the power supply line. Capacitors 21, 22, 2n
The power supply voltage drops for a moment due to the inrush current into the capacitor, and the voltage returns as the capacitor is charged. When the number of connected packages is small, the number of capacitors connected to the power supply line is small, so that the charging time becomes long and the voltage recovery time becomes long. For this reason, the circuit of another package may malfunction. In order to reduce the voltage recovery time, the capacity of the output capacitor 31 in the common power supply is increased and the charging time of the capacitor of the insertion package is reduced.

[0005]

In this conventional load insertion / extraction protection system, as the number of connected packages increases, the number of capacitors connected to the power supply line also increases, the total capacitance of the power supply line increases, and the output voltage decreases. Therefore, there is a drawback that a common power supply with a large current capacity is required for the power supply package as a countermeasure.

[0006]

According to the load insertion / extraction protection system of the present invention, a plurality of branch power supply lines branched in parallel from a power supply package having a fixed capacitance in an output section are connected to a plurality of load packages to connect a branch power supply. In a load insertion / removal protection system in which the load package is inserted / removed in a supplied state, a detection unit for detecting the insertion / extraction state of the load package, a variable capacitance type capacitor connected in parallel to the power supply package, and the variable capacitance type capacitor Control means for varying the capacitance of the variable capacitance type capacitor, and when the detection means detects pulling out of the load package, the control means is operated to increase the capacitance of the variable capacitance type capacitor.

[0007]

The present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of an embodiment of the present invention, and FIG. 2 is an explanatory diagram of the total capacitance of a power supply line of this embodiment. Figure 1
In the figure, 11, 12 to 1n are load packages connected to the power supply line, and 21, 22 to 2n are capacitors C1, C2, C for removing noise of each package power supply input section.
n, 3 are common power supply packages, 13 is an output capacitor of the power supply package 3, 4 is a variable capacitor, 1 is a detection unit for detecting insertion / extraction of the load packages 11, 12 to 1n, 2
Inputs the detection data of the detection unit 1 and
Is a control unit that outputs the control voltage.

Next, the operation of this embodiment will be described. Detector 1
Detects the insertion / removal (connection) status of each package. For example, in FIG. 2, when the pull-out of the load package 11 is detected, the capacitance decreases by about 1 μF. Therefore, the controller 2 increases the capacitance of the variable capacitor 4 by the amount of the capacitor C1. Therefore, the shaded area in FIG. 2 represents the amount compensated by the variable capacitor 4, and the total total capacitance is kept constant. In order to explain FIG. 2 more specifically, the capacitance of the filter capacitor of each package is 1 μF,
The output capacitor capacity of the power supply package is 2 μF, and the total capacity of the power supply line required to prevent malfunction is 12 μF, and the number of connected packages is 10. In the present invention, the variable capacitor capacitance is set as indicated by the shaded area by the number of connected packages so that the total capacitance becomes 12 μF. In the case of the prior art, if the same effect is to be obtained even if the number of connected packages is 0, the total capacitance when the number of connected packages is 10 is 22 μF as shown in FIG. , A power supply package suitable for charging with a capacity of 22 μF is required.

[0009]

As described above, according to the present invention, the detection unit for detecting the connection state of the package connected to the power supply line, the variable capacitor connected in parallel to the power supply line, and the control unit for the variable capacitor are provided. This has the effect of preventing malfunctions when the load package is inserted without increasing the load capacity of the power package. It is particularly effective when the noise standard of the package is strict and the capacitor capacity of the filter is large, or when the number of packages to be connected is large.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention.

FIG. 2 is a characteristic explanatory diagram of the present embodiment.

FIG. 3 is a block diagram of a conventional load insertion / extraction protection system.

FIG. 4 is a characteristic explanatory diagram of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 detection part 2 control part 3 power supply package 4 variable capacitor 11,12-1n load package 21,22-2n, 13 capacitor 31-3n circuit body

Claims (2)

[Claims] 1. A load for inserting / removing the load package in a state in which a plurality of branch power supply lines branched in parallel from a power supply package having a fixed capacitance in an output portion are connected to a plurality of load packages and branch power is supplied. In the insertion / extraction protection system, the load package is provided with a detection means for detecting the insertion / removal state, a variable capacitance type capacitor connected in parallel to the power supply package, and a control means for varying the capacitance of the variable capacitance type capacitor. A load insertion / removal protection system, wherein when the means detects pulling out of the load package, the control means is operated to increase the capacitance of the variable capacitance type capacitor. 2. The sum of the fixed capacitance of the power supply package, the capacitance of the variable capacitance type capacitor, and the capacitance of the load package is kept substantially constant regardless of the insertion and removal of the load package. The load insertion and removal protection method described in 1.