JPH0110616Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a high voltage test device that automatically determines whether a device is good or bad by applying a high voltage.

In general, when testing the withstand voltage of devices, some special devices, such as photo couplers, require several voltage sources to be used.
A high voltage of kV to several tens of kV is required.

Representative examples of conventional methods for performing such withstand voltage tests are shown in FIGS. 1 and 2. In FIG. 1, the high voltage test equipment includes a high voltage power supply 1, a voltmeter 2 for measuring the output voltage of the high voltage power supply 1, a switch 3,
One or more devices to be measured 4 ₁ , 4 ₂ . . . 4 _o ,
The above elements 4 ₁ , 4 ₂ ... 4 during discharge under high voltage
Protective resistances R ₁ , R ₂ ...R _o to prevent destruction of _o ,
and neon lamps 5 ₁ , 5 _{2 .} . . 5 _o for discharge detection. That is, when the switch 3 is closed and the output voltage of the high voltage power supply 1 is sequentially increased to the specified value while reading the indicated value of the voltmeter 2, the withstand voltage value of each of the elements to be measured 4 ₁ , 4 ₂ . . . 4 _o Due to the difference in the brightness of the neon lamps 5 ₁ , 5 ₂ . . . 5 _o , a difference occurs in the lighting brightness. An operator judges this brightness (luminance) and makes a judgment as to whether the product is good or bad. However, in this method, since the operator makes a judgment as to whether the product is good or bad based on the difference in brightness, individual differences occur among the operators. There is a method shown in FIG. 2 that compensates for this drawback. This device connects ammeters 6 ₁ , 6 ₂ ... 6 _o instead of the neon lamps 5 ₁ , 5 ₂ ... 5 _o shown in Fig. 1,
After applying a specified voltage, the operator reads the indicated values of these ammeters 6 ₁ , 6 _{2 .} . . 6 _o to determine whether the product is good or bad. This method improves accuracy by several orders of magnitude compared to the neon lamp method shown in FIG. Furthermore, as shown in FIGS. 3a and 3b, operational amplifiers (commonly called operational amplifiers) may be used in place of the ammeters 6 ₁ , 6 ₂ . . . 6 _o .
That is, in FIG. _3a , the detection _{resistance R}
...6 Connect between a and b in Figure 2 instead of _o . Then, the current i flowing through the detection resistor R _x is processed by the operational amplifier 7 and the resistor R to obtain a voltage E ₀ of the detection resistor Rx×current i. Similarly, in Figure 3b, the second
By connecting the input terminal of the operational amplifier 7 to point a in the figure, an output voltage of R×i=E ₀ is obtained. In other words, each of Figure 3 a and b is a current-voltage (I/
V) This is a component of the converter, and by inputting the output voltage _E0 of this I/V converter and the reference voltage to a comparator (not shown), it can automatically determine whether it is good or bad. It is something that can be done.

By the way, a normal withstand voltage test is carried out under conditions in which a specified voltage is applied for a specified period of time. FIG. 4 shows this. There are various prescribed times, but
Generally, the time is from several seconds to several minutes, and the specified voltage is several kV. Conventionally, the application of this specified voltage was
As shown in the figure, the voltage is increased sequentially and is applied for a specified time after reaching the specified voltage. However, with this method, it takes time to reach the specified voltage, which increases the measurement time. and,
As a method to shorten this measurement time, the first
2, a method is employed in which the output voltage of the high voltage power supply 1 is first brought to a specified voltage, and then the switch 3 is closed. However, in this method, unnecessary damage may be caused to the devices to be measured 4 ₁ , 4 ₂ . . . 4 _o due to chattering or the like at the contacts of the switch 3. In addition, Fig. 6 a to d
shows typical examples of current and voltage.

This idea was made in view of the above circumstances,
The purpose is to provide a high voltage test device that can automatically apply high voltage, shorten measurement time, and determine whether the device under test is good or bad without damaging it. be.

An embodiment of this invention will be described below with reference to the drawings. In FIG. 7, the high voltage test device includes a high voltage setting section 11, a pretest voltage setting section 12, a high voltage power supply generating section 13, a standard voltage generating section 14, and a protective resistor.
R ₁ to _{R o} , detection resistor R' ₁ to R' _o , switch 15 ₁ to 1
5 _o and 16 ₁ to 16 _o , I/V converter 17 ₁ to 17
_o , comparators (good/bad discriminator) 18 ₁ to 18 _o , etc. Further, 19 ₁ to 19 _o are elements to be measured. Specifically, the high voltage setting section 11 is connected to one input end of the high voltage power generation section 13, and the pretest voltage setting section 12 is connected to the other input end of the high voltage power generation section 13. This high voltage power generation section 13
A protective resistor is connected between one output terminal and the other output terminal of the
R ₁ , switch 15 ₁ , device under test 19 ₁ , detection resistor
R′ ₁ and switch 16 ₁ are connected in series. The input side of the detection resistor R' ₁ is connected to one input terminal of the I/V converter 17 ₁ , and the other input terminal of the I/V converter 17 ₁ is connected to the other input terminal of the high voltage power supply generating section 13. The output end is connected. In addition, I/V converter 17 ₁
Diodes 20 ₁ and 21 ₁ are connected in opposite directions between one input terminal and the other input terminal. and,
The output terminal of the I/V converter 17 ₁ is connected to one input terminal of a comparator 18 ₁ , and the output terminal of the standard voltage generation section 14 is connected to the other input terminal of the comparator 18 ₁ . Furthermore, diodes 22 ₁ and 23 ₁ are connected in opposite directions between one input terminal and the other input terminal of the comparator 18 ₁ . Although the case with reference numeral 1 has been described above, the cases with reference numerals 2 to n have the same structure, so the explanation thereof will be omitted.

FIG. 8 shows a specific configuration of the high voltage setting section 11, pretest voltage setting section 12, and high voltage power supply generating section 13 that generate the specified voltage. In the figure, a commercial power source (AC100V) is connected to an automatic voltage stabilizer (AVR) 24. This automatic voltage stabilizer 24 prevents the influence of fluctuations in the commercial power supply on high voltage. automatic voltage stabilizer 24
The output of is connected to the primary side 25a of the high voltage transformer 25. The secondary side 25b of the transformer 25 has a plurality of output taps (20, 40, 60, 80,
It is 5 taps of 100V. ), and each tap is connected to one end of non-contact type relays (commonly known as solid state relays) 26 ₁ to 26 ₅ . The other ends of these relays 26 ₁ to 26 ₅ are both connected to a high voltage transformer 27
It is connected to the primary side 27a of. This transformer 27
is a transformer with a magnification of n times, and the secondary side 27
b has a number of output taps, switches 28,
A high voltage can be generated by the potential difference between the 29 taps. In other words, if the operator first sets the switches 28 and 29 to predetermined positions, the relays 26 ₁ to 26 ₅ can obtain the specified voltage, and the work that conventionally required the operator to raise to the specified voltage can be automatically done. It is something to be carried out. Also, 3
0 is a register, and the output signals SD ₁ to _{SD 5} of this register 30 are sent to the relays 26 ₁ to 26 ₅ respectively.
It is now being sent to

Next, the operation will be explained with reference to the timing chart shown in FIG. First, when a start switch (not shown) is turned on by the operator, a clock pulse (CP) synchronized with the commercial power supply is sent to the register 30.
is input. Therefore, the signal from register 30
SD ₁ to _{SD 5} are output sequentially (here, the signal SD ₁
- Only one of SD ₅ is always output). As a result, relays 26 ₁ to 26 ₅ are sequentially closed.
By sequentially closing the relays 26 ₁ → 26 ₂ → 26 ₃ → 26 ₄ → 26 ₅ , 20V (20%), 40V (40%), 60V (60V) are applied to the primary side 27a of the transformer 27.
%), 80V (80%), and 100V (100%) are sequentially applied, and as a result, a voltage multiplied by n is output to the secondary side 27b of the transformer 27.

The output signals SD ₁ to _{SD 5} of the above register 30 are synchronized with the commercial power supply, so 20V → 40V → 60V →
The timing of switching from 80V to 100V can be increased at the timing when the output voltage crosses 0V (zero cross). The application time for the specified time is determined by counting the time from the time when the primary side 27a of the transformer 27 reaches 100% (the relay ₂₆₅ is closed, that is, the output signal of the register 30 is _SD5 ), and when the specified time elapses, the register 30 Reset. As a result, the output signal SD ₅ is reset, and the output signal SD 5 of the transformer 27 is reset.
The next voltage becomes 0V. In addition, transformer 27-2
Resistors R _c1 and R _c2 are connected in series between the next output terminals 31 and 32, and the output voltage is appropriately divided by these resistors R _c1 and R _c2 . This makes it possible to check the output voltage easily and safely.

FIG. 10 shows the configuration of the output section, and here, for example, only one circuit portion of the comparator ₁₈₁ is shown. The comparator 18 ₁ compares the standard voltage and the detection voltage (the potential difference between both terminals of the detection resistor R' ₁ and the switch 16 ₁ in FIG. 7, the potential difference between a and b in the figure), and determines that the detection voltage ≧ the standard voltage. If the detected voltage is smaller than the standard voltage, a signal of "0" level (determined as good) is output.
The output signal of the comparator 18 ₁ is input to a relay driver (DR) 34 ₁ , which turns on and off the contacts of the relay 35 ₁ (switches 15 ₁ and 16 ₁ ). Here, as the relay ₃₅₁ , a relay that does not operate with a short drive signal is used. That is, when the output of the comparator 18 ₁ is "1" level (device under test 19 ₁ is defective), the switches 15 ₁ and 16 ₁ are turned off, and when the output of the comparator 18 1 is at "0" level (device under test 19 ₁ is good), the switches 15 1 and 16 1 are turned off. Sometimes switch 15 _1,1
6 ₁ is on. Furthermore, when no high voltage is applied to the device under test 19 ₁ , the comparator 18 ₁
Since the output of is at “0” level, switch 15
₁ , 16 ₁ are on. Further, a noise filter 36 ₁ is connected in parallel to the relay 35 ₁ to remove noise from the relay 35 ₁ . Furthermore, if the comparator ₁₈₁ and the like are covered with a magnetic shield, the effects of external noise etc. can be reliably prevented.

On the other hand, the output signal of the comparator ₁₈₁ is sent to a display section (not shown), and a pass/fail display is performed. Note that FIG. 11 shows the device to be measured 19.
₁ to 19 _o and their peripheral circuit configurations.

That is, the above-mentioned high voltage test apparatus has the following various features.

Since it is possible to determine whether the device under test is good or bad while sequentially increasing the high voltage power supply up to the set specified voltage, the measurement time is shortened.

It is possible to detect that a discharge current exceeding the specified value has flowed before reaching the specified voltage, and by turning off the switch, it is possible to prevent overload on the device under test (pretest function).

Since the voltage is sequentially increased using a zero-crossing method, unnecessary noise can be prevented from occurring.

Since two high voltage transformers are used, it is easy to set the output voltage.

The input power supply (100V) is stabilized with an automatic voltage stabilizer, so there is no fluctuation in the high voltage output value due to input fluctuations.

Even discharge states (Fig. 6c, d), which could not be detected with conventional meter types, can be reliably detected.

FIG. 12 shows another embodiment, in which the relay 2
The operations of 6 ₁ to 26 ₅ are the same as in the above embodiment, but
A plurality of taps are provided on the secondary side 25b of the transformer 25, and the potential difference between the switches 37 and 38 is connected to the transformer 27.
The configuration is such that the voltage is applied to the primary side of the That is, in the transformer 27, the output condition of the secondary side 27b is determined by the input condition of the primary side 27a, and a voltage multiplied by n is output to the secondary side 27b. Therefore, the manufacturing cost of the transformer 27 is lower than in the above embodiments, and the switches 37 and 38 do not need to switch between high voltages, so they can be used for low voltages, which is advantageous in terms of longevity.

As described above, according to this invention, high voltages are automatically applied sequentially, which reduces measurement time and allows high voltage to be used to determine whether the device under test is good or bad without damaging it. We can provide pressure testing equipment.

[Brief explanation of the drawing]

Figures 1 to 3 a and b are circuit diagrams showing the configuration of conventional high voltage test equipment, and Figures 4 and 5 are circuit diagrams showing the configuration of conventional high voltage test equipment.
The figure is a waveform diagram of the specified voltage, Figures 6 a to d are voltage and current waveform diagrams for explaining the operation of the above device, and Figure 7 is a waveform diagram of the specified voltage.
The figure is a circuit diagram showing the configuration of a high-voltage testing device according to an embodiment of the invention, FIG. 8 is a diagram showing the specific configuration of the high-voltage power generation section, etc. in the device, and FIG. 9 explains the operation of the same. Voltage waveform diagram and timing chart for , Figure 10 is a diagram showing the configuration of the output section,
Figure 11 is a diagram showing the configuration around the device under test.
FIG. 2 is a diagram showing another embodiment. 11... High voltage setting section, 12... Pretest voltage generation section, 13... High voltage power generation section, 14... Standard voltage generation section, 15 ₁ to 15 _o , 16 ₁ to 16 _o ...
Switch, 17 ₁ ~ 17 _o ...I/V converter, 18
₁ to 18 _o ... Comparator, 19 ₁ to 19 _o ... Device under test, 24... Automatic voltage stabilizer (AVR), 25...
High voltage transformer, 26 ₁ ~ 26 ₅ ... Relay, 27
...High voltage transformer, 28,29...Switch,
30...Resistor, _R1 ~R _o ...Protection resistor, _R'1 ~
R′ _o ...Detection resistance.

Claims (1)

[Claims for Utility Model Registration] (1) High voltage is applied to the device under test, and the quality of the device is determined.
A high withstand voltage test device for determining defects, comprising: a voltage stabilizing means for preventing the influence of alternating current input fluctuations on high voltage; a first high voltage transformer into which the output of the voltage stabilizing means is input to the primary side; Relay means provided for each output tap that outputs the voltage of a plurality of output taps from the low voltage side to the high voltage side provided on the secondary side of this first high voltage transformer, and the same number of bits as the number of the above relay means. When the logic value "1" level is maintained, the corresponding relay means is closed, and the voltage is inputted to the first high voltage transformer sequentially from the low voltage side to the high voltage side at the same frequency as the voltage input to the first high voltage transformer. a register that is stepped to the logic "1"level; a second high-voltage transformer that inputs the voltage output from the relay means to the primary side, multiplies it by n and outputs it to the secondary side; A means for detecting a flowing current, a comparator for comparing a detected voltage value obtained by this means with a specified voltage value, and a device to be measured whose detected voltage value is determined to be greater than the specified voltage by this comparator. and means for interrupting application of the voltage output from the secondary side of the second high-voltage transformer to the device under test when the detected voltage value is determined to be larger than the specified voltage value. High voltage test equipment featuring: (2) The high voltage test device according to claim 1, wherein the comparator is provided with means for preventing the influence of external noise. (3) Claim 1 of the utility model registration claim characterized in that a relay that does not operate with a short drive signal is used as the relay that drives the contact connected to the corresponding element with the output of the comparator. High voltage test equipment.