JPS5880569A - Load device - Google Patents

Abstract

PURPOSE:To obtain a load other than real resistance by detecting voltage applied to an input terminal to supply it to a control part, programming values calculted through a real time clocking part and a value calculating part in a digital power source part and connecting the power source part to the input terminal through a resistor. CONSTITUTION:A voltage detecting part 10 detects voltage VIN applied to an input terminal 1 and applies the voltage to a control part 11. Values successively calculated through a real time clocking part 12 and a value calculating part 13 are programmed in a digital program power source 14 from the control part 11. The output voltage of the power source 14 is applied to one side of a resistor 9 of which resistance is fixed and the input terminal 1 is connected to the other side of the resistor 9. The value calculating part 13 finds VP from a prescribed formula in every DELTAt in accordance with real time clocks by using external voltage VIN and the known internal resistance RO for loads RO, LO, CO to control the program power source 14, so that a load other than the real resistance RO is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a load device used when inspecting a DC stabilized power supply.

The current waveform that flows when a load is continuously applied to the 1lIIc source is categorized into a 3-point slope. Depending on whether the load is pure resistance, inductance, or capacitance, the equivalent circuit can be written as (C) in Figure 1, and the current waveform after connecting the power supply and each load will change over time. It becomes like yoshi (a)'(b)' (c bi).

Conventionally, when using a transistor as a semiconductor load, it was possible to operate it only as a constant current load or a constant resistance load. Figure 3 shows a type load circuit. In Figure 2, the input terminal l is
iLfl, and transistor 2. Flow to ground through resistor 3. The current at this time is converted into a stain voltage by the resistor 3, and the error with the voltage 15, which is the giant standard setting current, is amplified by the differential amplifier 4, and the transistor 20 pace is controlled.
9- Input the running current vIk-.

In Fig. 3, [Fig. 2] The sucked current is converted into a voltage by the resistor 3, and the value and the voltage at the input terminal l are added to the divider 6 to calculate the ratio. Take.

That is, the resistance value at that time is calculated, and the base of the transistor 20 is controlled using the differential amplifier 4III so as to maintain the resistance value set by the table voltage source 8. As described above, the conventional system has the disadvantage that it can only be used as a load whose current value is constant over time like a pure resistor.

The present invention provides a load device that can be used as a load such as inductance and capacitance in addition to the conventional pure resistance. In other words, it provides a load that operates like a coil load or a capacitor load, as shown in (b) 7' (C) in Figure 1. Lo is the resistance R in the coil, which is the same as that of the first WJ (b).
The response waveform when a DC voltage v1M is expressed as a series circuit of @ and Tori is (bY).

The load is wi1 (resistance inside the capacitor as shown in d) and C
If expressed as a series circuit with 0, the response waveform when DC voltage VIN is applied is (W of ct'< current, current ■ at that time.

If we lengthen the equation, we can achieve a load in which the current changes with time t like this.

According to the present invention, the input terminal, the resistor, the voltage detection section, the real-time lock section, and the number 1.1! At, the input terminal is connected to the input terminal of the calculation section, the programmable voltage i1 section, and the control section; This output terminal is connected to the input terminals of the #7I! section, and the input/output terminals of the real-time clock section and the VI calculation section are connected to the respective input/output terminals of the control section. -1#
A load device is obtained, characterized in that the output terminal of J6 and the input terminal of the programmable power supply section are connected, and the output terminal of the programmable power supply section J6 is connected to the other terminal of the resistor.

Next is a book +1! One embodiment of the present invention will be explained using Figure 4. Voltage detection [1
0 digitally and added to the control section 11.

9. Connect the control 1g1l to the real-time click unit 12 and the numerical calculation s13, and send the values calculated by the numerical calculation 13 for each instant of time to the digital program power source 14 from the control Mh511. Apply the output of the program voltage 14 to one side of the low resistor 9, which has a determined low value, and the other side of the resistor 90 to the input terminal 1! i
! Continue. By doing *a like Jin, the externally applied '4 voltage ■, N and the output voltage V of the program voltage fi7A14.
The relationship between prOg and the value RC(2) of resistor 9 is expressed as shown in FIG. The following relational expression can be found.

Therefore, −t RC′IJ ,°, Vprog−V, , (1−V(1−e ))
In addition, when the capacitance is +C, (the internal resistance is internal resistance), the current I has a value of I--e-1, so from (1), the coefficient of 0, C, and 4 can be found.

In this way, load vision that requires Z, Lo, Cn tQ
Using the external voltage ■1N and known internal resistance Hd2) measured with the voltage needle at t and the value of the known internal resistance Hd2), use the numerical calculation method 13 according to any of the above (1), (2), and (3) according to the real-time clock. Plug in the power of Vprog and Progr
If ami44m 14 is 1311, Figure 1(a)'
(b)'(cl') can be produced as a load.

Also, for non-linear loads, etc., the required current can be determined in advance by FIkl.
l! This can be achieved by controlling the program power supply Vprog so as to do so.

Above, we have described the case where the input voltage V□ is constant over time, but when the input voltage VsN changes, the voltage to be programmed Vpro
If g is changed as ΔVprog for every Δt, the change Δ■ for every Δt in the current ■ absorbed by the load can be changed by equation (1), and how can we control ′■・8ΔI? I can do it.

As described above, by using the present invention, it becomes possible to realize a load other than pure resistance, which was previously impossible.

[Brief explanation of the drawing]

Figure 1 is a diagram showing the relationship between the load circuit and current waveform. Figure 2 shows a conventional constant current load circuit. Figure 3 shows a constant resistance load circuit. Fourth
The figure shows an embodiment of the load device of the present invention. FIG. 5 shows a principle diagram of the present invention. In the figure, (B) and (C) are the equal current response waveforms of pure resistance, inductance, and capacitance loads, respectively. In addition, l is the load terminal, 2 is the transistor, and 3 is the current detection resistor. , 4, 7 are differential amplifiers, 5, 8
1 is a reference setting voltage source, 6 is a divider circuit, 9 is a resistor, 10 is a voltage detection section, 11 is a control product, 12 is a real-time clock section, 13 is a numerical calculation section, and 14 is a programmable voltage section. Also,#! Figure 2 Hola #! In Figure 5, the thick lines indicate the areas where the load and overflow flow. . Dice 1

Claims (1)

[Claims] The input terminal is composed of a resistor on the input terminal, a voltage detection section, a real-time detection section, a numerical calculation section, a blemogram pull power supply section, and a control section, and the input terminal is connected to one terminal of the resistor and the input terminal of the voltage detection section. and connecting the output terminal of the voltage detection section to the input terminal of the control section, and connecting the input/output terminals of the real-time click section and the numerical calculation section to the respective input/output terminals of the control a1 section, Said side aiI
f! 6 and the input terminal of the programmable power supply section are connected to each other, and the output terminal of the programmable power supply section is connected to the other terminal of the resistor.