This standard specifies the test method for rectifier three-phase bridge modules composed of semiconductor diode chips. This standard is applicable to power semiconductor rectifier three-phase bridge modules with current of 5A and above. Three-phase bridge components composed of rectifier diodes should also be used as a reference. JB/T 6307.3-1992 Power semiconductor module test method rectifier three-phase bridge JB/T6307.3-1992 Standard download decompression password: www.bzxz.net

JB/T6307.
.Subject content and scope of application
Standard of the Machinery Industry of the People's Republic of China
Test method for power semiconductor module
Three-phase bridge of rectifier tube
JB6307.3-92
This standard specifies the test method for three-phase bridge module of rectifier tube composed of semiconductor diode chips. This standard is applicable to three-phase bridge module of power semiconductor rectifier tube with current of 5A and above. Three-phase bridge components composed of rectifier diodes should also be used as a reference.
2 Terminology
The scope of this terminology is only the terminology applicable to three-phase bridge rectifier module not provided in GB2900.32 "Electrical Terminology Power Semiconductor Devices".
2.1 Reverse repetitive peak current (IxRm)
The maximum reverse peak current when the reverse repetitive peak voltage is added to the three terminals of the module AC terminal. 2.2 Reverse repetitive peak voltage (VRRM)
The maximum instantaneous value of the reverse voltage that appears at the three terminals of the module's AC connection terminal. Including all repetitive transient voltages, but excluding all non-repetitive decompression voltages.
2.3 Forward peak voltage (Vym)
The maximum decompression peak voltage when the two chips in the module's inner arm are subjected to multiple times the rated DC output current. 2.4 Forward peak current (Im)
The forward peak current that flows into the chip from the module's AC connection terminal, including all repetitive transient currents. 2.5 Reverse non-repetitive peak voltage (VRsM) The transient reverse voltage of any non-repetitive maximum instantaneous value that appears at the three terminals of the module's AC connection terminal. 2.6 Equivalent junction temperature
Thermoelectric calibration relationship based on the two chips in the module's inner arm. The junction temperature obtained by electrical measurement. 2.7 Thermal resistance (R+)
The ratio of the temperature difference between the module's equivalent junction temperature and the reference point under thermal equilibrium conditions to the power dissipation that produces the temperature difference. 3
Circuit symbols and general test requirements
Circuit symbols
Adjustable AC voltage source;
Adjustable pulse power supply;
-Adjustable constant current source;
Approved by the Ministry of Machinery and Electronics Industry on June 26, 1992, No. 56
Implementation on January 1, 1993
Constant current source,
Transformer;
Diode;
Crystal tube;
Resistor
Adjustable resistor:
Capacitor;
Inductor:
Switch;
Voltmeter:
PA-Ammeter:
Wattmeter;
Oscilloscope:
Recording instrument
Test module.
3.2 General requirements for testing
JB6307.3-92
3.2.1 Test power supply
3.2.1.1 All power supplies in the test circuit should have clamping measures to protect the tested module from damage due to transient phenomena such as surges during switching, adjustment and measurement.
3.2.1.2 Power supply fluctuations should not affect the measurement accuracy. The frequency of the AC power supply is 50±1Hz, the waveform is a sine wave, and the waveform distortion factor is not greater than 10%; the ripple factor of the DC power supply should not be greater than 1% for reverse characteristic measurement and should not be greater than 10% for forward characteristic measurement. 3.2.2 Measuring instruments and circuit conditions
3.2.2.1 The instrument should have protection measures to prevent overload caused by faults or wiring errors in the tested module. In order to prevent unwanted half-cycle pulses from entering the amplifier of the oscilloscope, diode protection can be connected in the circuit. 3.2.2.2 When measuring high current devices, the voltage measurement node should be separated from the current conduction node. When the voltage drop in the circuit when measuring current and the current in the circuit when measuring voltage cause considerable errors, the measurement results must be corrected. When measuring low currents, appropriate precautions should be taken. Ensure that stray capacitance and inductance do not affect the measurement accuracy, and make the parasitic circuit current and external leakage current much smaller than the measured current, or correct their influence in the measurement results. 57
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3.2.2.3 The accuracy of DC and AC voltmeters, ammeters and shunts for measurement should generally be 0.5 or higher. And the influence of their impedance on the measurement system should be negligible. Instruments with an accuracy lower than 0.5 can be used in the following cases: a.
has no significant impact on the measurement results;
has no significant impact on the determination of qualification or failure: b.
There is no 0.5 standard instrument according to national standards. 3.2.3 Environmental conditions
3.2.3.1 Room temperature test atmospheric conditions:
Benchmark atmospheric conditions: temperature 25℃. Relative humidity 65%. Air pressure 101.3×10°Pa; Arbitration test atmospheric conditions: temperature 25±1℃, relative humidity 63%～67%, air pressure 86×10~106×10°Pa; Conventional test atmospheric conditions: temperature 5～35℃. Relative humidity 45%～85%, air pressure 86×10°~106×10°Pa. When relative humidity and atmospheric pressure have no significant effect on the measured parameters, the atmospheric conditions can be based only on temperature. When the room temperature deviates far from 25C, and the temperature has a significant effect on the measured parameters, the measurement results should be corrected according to 25℃. 3.2.3.2 When the test module is tested in a high or low temperature box or on a temperature control fixture for high temperature or low temperature test, the temperature fluctuation is within the range of 1 to 1℃. When the temperature has no obvious effect on the measured parameters, the temperature difference fluctuates within the range of 12 to 102°C, otherwise the measurement results should be corrected. Unless otherwise specified, high temperature test refers to the test at T-\°C. T is the rated maximum junction temperature; low temperature test refers to the rated minimum junction temperature. 4 Electrical Characteristics Test
4.1 Reverse Repetitive Peak Current (IRkM)
4.1.1 Purpose
Measure the reverse repetitive peak current of the module under specified conditions. 4.1.2 Principle circuit and requirements
Figure 1 Reverse repetitive peak current test circuit
VD1.VD2-diodes that provide negative half-cycle voltage, so that only the reverse resistance of the module is measured; when E breaks down, the current flowing through E can be limited to prevent damage to E and the instrument; 3
R1-current limiting protection resistor, its value should be
R2 non-inductive resistor for calibrating current;
Peak reading meter can be used instead of oscilloscope, and the peak current meter should be able to display the current value when the reverse voltage reaches the peak value. 4.1.3 Specified conditions
Junction temperature: 25℃, Tm
Reverse voltage: reverse repetitive peak voltage (VxRM); AC voltage source frequency: 50Hz.
Test procedure
Place switches S1 and S2 at A and B respectively;
Adjust the AC voltage source G so that its arms 3-4 are subjected to the specified reverse repetitive peak voltage. The current value displayed on the oscilloscope or peak reading ammeter is the measured reverse repetitive peak current IRRM(34)C.
Place switches S1 and S2 at B and A respectively. According to procedure b, the reverse repetitive peak current IkRM(16) can be measured. Direct the switches S1 and S2 to A and C respectively, and according to procedure b, the reverse repetitive peak current IRRM (4s>d) can be measured.
Direct the switches S1 and S2 to C and A respectively, and according to procedure b, the reverse repetitive peak current IRRM (12) Direct the switches S1 and S2 to B and C respectively, and according to procedure b, the reverse repetitive peak current IRRM (54) Direct the switches S1 and S2 to C and B respectively, and according to procedure b, the reverse repetitive peak current IgRM (2n)g.
Take bcdef and g in procedure The larger value is defined as the module's reverse repetitive beep current IsRMh.
4.2 Forward peak voltage (Vm)
4.2.1··Purpose
Measure the module's forward peak voltage using the pulse method under specified conditions. 4.2.2 Principle circuit and requirements
Protection resistor:
Figure 2 Forward peak voltage test circuit
Non-inductive resistor for calibrating current readings:
Thyristor for controlling current pulses,
: Generates pulse current when on. Pulse The pulse width and repetition rate of G should be such that the internal heating during the measurement can be ignored. A peak reading meter can be used instead of an oscilloscope; the peak voltmeter should be able to display the voltage value when the forward current reaches its peak value. 4.2.3 Specified conditions.
a.: Junction temperature: 25°C for factory inspection, 25°C and Tb for type inspection, forward peak current: module rated DC output current I. Yuan/3 times (yuan can be taken as 3); the wire used to connect the DC terminal of the tested module should be as short as possible. 4.2.4.Test procedure
The module under test is fastened to the fixture or heat sink, and its DC terminals are connected with wires. The test point for measuring the peak voltage (VM) should be as close to the module housing as possible:
Note: Pay attention to eliminating contact voltage drop, and the current and voltage sampling should be a four-point connection method. b. Turn switches S1 and S2 to A and B respectively. C.
The voltage of the pulse power supply gradually increases from zero, so that the forward current flowing through arms 3-4 of the module under test is adjusted to the specified value. At this time, the value displayed by the oscilloscope or peak reading voltmeter is the measured forward peak voltage VFMh, switch S1 and S2 to C and B respectively, and according to procedure b, the forward peak voltage VFM (2>; i. Take the larger value in procedure bcdefg and h, and set it as the forward peak voltage VM of the module. 4.3 Forward volt-ampere characteristics (VFM-Irm curve) 4.3.1 Purpose
Under specified conditions, use the pulse method to test the relationship between the forward peak voltage and the forward peak current, and draw a curve. 4.3.2 Principle circuit and requirements
Meet 4.2.2.
4.3.3 Specified conditions
a. Junction temperature: 25℃ and Tm;
b. Forward current range: zero to more than 1.5 times of the rated DC output current I of the module. 4.3.4 Test procedure
Confirmed by 4.2.4i The arm with the largest forward peak voltage is used to test the forward volt-ampere characteristics of the module; a.
The different forward peak currents and corresponding forward peak voltages of the arm are measured at 25°C and T respectively; b.
On the same arithmetic coordinates, two forward volt-ampere characteristic curves of 25°C and T are broadcast. If the test current range is relatively large, the curve can be drawn with a single c.
logarithmic coordinates.
5 Thermal characteristics test
5.1 Basic requirements
5.1.1 If the time from power application to measurement is doubled, and the change in the measurement result is no greater than the specified error, it can be considered that thermal equilibrium has been achieved.
5.1.2 All electrical tests shall not be conducted unless otherwise specified or the measurement is completed under pulse conditions. All measurements should be carried out under thermal equilibrium conditions. 5.1.3 Reference point location: The geometric center point of the long side of the module housing bottom plate, with a point depth of 1mm; or as given by the manufacturer. 5.1.4. Method for measuring reference point temperature (Tt) The reference point temperature is measured using a thermistor with negligible heat capacity. To ensure that the thermal resistance between the thermistor and the module housing bottom plate is negligible, flux, fixtures or clamps are used to securely fit the thermistor to the housing bottom plate. For the case where the reference point is 1mm deep into the surface, a thermocouple with a cut diameter of no more than 0.25mm is inserted into the hole for measurement. The hot end of the thermocouple should be welded to form a small ball (the diameter of the solder ball should be less than 0.8mm), and it should not be formed by twisting or soldering. Insert the hot end of the thermocouple into the reference point hole, and tap the metal at the edge of the hole to cover the thermocouple ball, so that the thermocouple is tightly attached to the housing bottom plate. Ground contact. Short circuit is not allowed at the hot end. The cold end of the thermocouple should be reliably maintained at 0℃ or a certain temperature value. 5.2 Thermal Resistance (R)
The measurement of thermal resistance (or transient thermal impedance) is based on the reading of equivalent junction temperature using thermistor parameters. Usually, the forward voltage of the chip at a small percentage of the rated current is used as thermistor parameter. The accuracy of this method is not specified, but 5.2.4 should be followed. 5.2.1 Purpose
Measure the thermal resistance between the junction of the chip in the module and the reference point. 5.2.2 Principle of the method
Apply different dissipated powers P1c1n), P2un) and P1ca), P2(4) and P1(s), P2(s6) to the three arms of the test module respectively, and adjust the cooling conditions to make arms 1-2 (or 3-4 or arms 5-6). When the junction temperature at the two power dissipations of P1 and P2 is the same, measure the temperature of the module reference point T1can), T2a2) and T1ca0), T2(ao and T1(5), T2(6) respectively, and use the thermistor voltage to check whether the same junction temperature is reached. Calculate the thermal resistance of the arm according to formulas (1), (2) and (3) respectively. S0
Tran)-Ta(1n)
P2(12)-Pr(12)
Reh(34)
T(34)—T2(84)
P2(34)P1(84)
The module thermal resistance is calculated according to formula (4).
5.2.3·Principle circuit and requirements
JB6307.3-92
T1(58)—T2(56)
P2C58)P1(58)
Rh12) · Reh(34) · Ra(s
Rhc12)·Re(2a)+Ro<12)·Rb(5e)+Rb(34)·Rb5a)S2
Figure 3 Thermal resistance test circuit
G1——Adjustable constant current source, this power supply should be able to output a load current I that makes the junction temperature of the chip in the test module reach or approach the rated junction temperature, and generate dissipated power in the junction of the chip in the module; DC reference current (thermal current) that monitors its junction temperature; PV—zero position method (balance elimination method) voltmeter, an electronic switch that periodically interrupts the load current I during the short period of time when the load current is periodically interrupted: a wattmeter that indicates I, and generates power consumption in the junction. PW-
5.2.4 Notes
When switching from load current I, to reference current I, transient voltages are generated due to excess charge carriers. If the module under test contains ferromagnetic materials, transient voltages will also be generated. Therefore, switch S2 should not be closed before these transient effects disappear. b. Usually the reference current I, should be selected to be large enough to keep the entire junction area conductive. The load current I, in 5.2.3 can be zero, that is, the dissipated power P, is also zero. Then the reference e.
point temperature T, in formulas (1), (2) and (3) is equal to the equivalent junction temperature when the power P, is applied. 5.2.5 Specified conditions
Load current: The power generated should make the equivalent junction temperature reach close to T, which is usually the rated DC output current I of the module. a.
is equal to the rated average forward current of a single chip in the module); reference current I2: its value should be large enough; use the recommended value of A3.1; b.
location of temperature reference point and installation of thermocouple: according to 5.1.3 and 5.1.4; time for measuring the voltage of reference current (thermal voltage): should be during 0.5~1ms after the load current is interrupted; the wire used to connect the DC terminal of the test module should be as short as possible: the cross-sectional area is determined by the current value. 5.2.6 Test Procedure
Connect the DC terminals of the test module with wires; a.
The test module is fastened to a temperature-adjustable heating fixture, and the thermocouple is fixed at the reference point; (that is,
Throw switches S3 and S4 to A and B respectively, first measure the thermal resistance Ra(a) of the inner arm 3-4 of the test module: the heating fixture is kept at a higher temperature, a smaller load current I is applied, and a dissipated power P13) is generated in the junction. After reaching thermal equilibrium; adjust the zero-position voltmeter PV to zero balance; record the reference point temperature T1c4), then keep the heating fixture at a lower temperature, increase the load current I, to power P2012) and heat the junction to the same junction temperature as P1(34 under power. This temperature is indicated by the zero balance of the zero-position voltmeter, record the reference point temperature T2(34, and calculate the thermal resistance Ra(34) according to formula (2);
JB 6307.3-92
d. Switch S3 and S4 to C and A and B and C respectively, and measure the thermal resistance Rbcan and Rb5 of the arms 12 and 5-6 of the tested module according to procedure C);
The thermal resistance of the module is calculated according to formula (4).
5.3 Transient thermal impedance Zht
5.3.1 Purpose
Test the transient thermal impedance between the junction and the reference point of the inner arm of the module. 5.3.2 Principle of method
Apply load current After the current is turned on and thermal equilibrium is reached, the power dissipation of the arms 1-2, 3-4 and 5-6 in the module is recorded respectively. The load current is cut off and the forward voltage of the reference circuit and the reference point temperature are recorded as a function of time. The calibration curve obtained with the same reference current is used to determine the equivalent junction temperature as a function of time. 5.3.3 Principle circuit and requirements
Figure 4 Transient thermal impedance test circuit
A constant current source G1 provides a negative current that generates power dissipation in the junction of the chip in the arm of the module under test; I-constant The DC reference current (thermal current) provided by the current source G2; S1-
Cut off the load
Indicates the current in the chip junction of the internal arm of the test module by the load current I;
Generate a wattmeter for power consumption;
5.3.4 Specified conditions
Same as 5.2.5
5.3.5 Test procedure
PS-Recording instrument for recording the relationship between thermistor voltage and time. PS
a. Use a wire Connect the DC terminals of the module under test; b. Use external heating to change the temperature of the module. Measure the forward voltage of the reference current I as a function of the equivalent junction temperature and draw a calibration curve;
The module under test is fastened to a fixture that maintains a fixed temperature, the thermocouple is fixed at the reference point, and switches S3 and S4 are respectively placed at A and c.
B, close S1, apply a load current I1 to the arms 3-4 of the module under test, generate a dissipated power P in its junction, and establish thermal equilibrium; d.Disconnect switch S1; cut off I1, and record the forward voltage (generated by I.) as a function of the cooling process time using the recording instrument PS. During the cooling period, record the corresponding reference point temperature at the same time; e.
Use the calibration curve to transform the recorded forward voltage curve into an equivalent junction temperature curve. Calculate the transient thermal impedance Zh(t)Zhn
[Tvs(0) Trd(o, ]-[T- -Trt( ]P
JB6307.3—92
Temperature when switch S1 is disconnected (t=0), ℃; where Tce)Tf(o)—
T(t), Ter(t)—temperature at time t, ℃. f. Switch S3 and S4 to C and A and B and C respectively. Same as cd and e. Test Za(t) of arms 1-2 and arms 5-6; g. Use the results of e and f. Calculate the thermal impedance of the module at different t values ​​according to formula (4) and draw a curve. 6 Rated value (limit value) inspection
6.1 Reverse non-repetitive bee value Voltage (VRsM) 6.1.1 Purpose
Under specified conditions, verify the reverse non-repetitive peak voltage rating of the module. 6.1.2 Principle circuit and requirements
Specified conditions
Figure 5 Reverse non-repetitive peak voltage test circuit A diode that provides a negative half-cycle voltage is used to test only the reverse characteristics of the module under test: an electromechanical switch or electronic switch that applies a reverse half-cycle power supply voltage to E (the conduction angle is approximately 180);
Junction temperature: 25°C, Tm;
A protective resistor;
A peak reading voltmeter. ||t t||Duration of half-cycle pulse: approximately 10ms, or 8.3, 1 or 0.1ms if otherwise specified; number of pulses or repetition frequency: not more than 5Hz; test voltage: reverse non-repetitive peak voltage (VrsM). Test procedure
Set the AC power supply voltage to zero;Www.bzxZ.net
Throw switches S1 and S2 to A and B respectively;
Disconnect switch S3 to increase the AC power supply voltage to the reverse non-repetitive peak voltage value; Close switch S3 during the reverse half cycle to apply the specified reverse non-repetitive peak voltage to arms 1 to 6 in the module; After the test, press 4 .1 Measure the reverse repetitive peak current; switch S1 and S2 to B and A respectively, and test the reverse non-repetitive peak current of arms 3-4 in the module according to procedures c, d, and e. Switch S1 and S2 to A and C respectively, and test the reverse non-repetitive peak current of arms 1-2 in the module according to procedures c, d, and e. Switch S1 and S2 to C and A respectively, and test the reverse non-repetitive peak current of arms 4-5 in the module according to procedures c, d, and e. Switch S1 and S2 to B and C respectively, and test the reverse non-repetitive peak current of arms 2-3 in the module according to procedures c, d, and e. 6307.392
Put switches S1 and S2 to C and B respectively, and test the reverse non-repetitive peak voltage of arms 5--6 in the module according to procedures c, d, and e,
k. If the measured reverse repetitive peak currents all meet the specified values ​​of the product standard, the reverse non-repetitive peak voltage rating of the module is confirmed.
6.2 Forward (non-repetitive) surge current (IpsM) 6.2.1 Purpose
Under specified conditions, verify the forward (non-repetitive) surge current rating of the chip in the module. 6.2.2 Principle circuit and requirements
Figure 6 Forward (non-repetitive) surge current test circuit PA - peak reading ammeter;
A diode blocking the forward voltage provided by transformer T2; - resistor for setting surge current, the resistance of this resistor should be greater than the forward resistance of diode VD1, R1 -
its resistance value should be as small as possible;
electromechanical switch or electronic switch with conduction angle; T1 -
protective resistor,
S1 - a high current low voltage transformer with approximately 180° during the forward (surge) half cycle through S1 to supply power for the forward (surge) half cycle. Its current waveform should basically be a sinusoidal half wave with a duration of approximately 10ms (or 8.3ms) and a repetition rate of approximately 50 (or 60) Hz; T2 - a low current high voltage transformer for supplying power for the reverse half cycle through diode VD1. If this transformer is fed by a separate power supply, its phase sequence must be the same as the phase sequence feeding T1. Its voltage waveform should be basically a half-sine wave; PV
peak reading voltmeter.
If necessary, a diode VD2 and its series switch S2 or a resistor R3 and its series switch S2 can be connected between points X and Y. VD2 is a balanced diode. Its forward resistance is approximately equal to the forward resistance of a single chip of the module under test. If resistor R3 is used, its resistance should be the same as the forward resistance of a single chip of the module under test. S2 is an electromechanical switch or an electronic switch. During the reverse half cycle of transformer T1, its conduction angle is approximately 180°.
6.2.3 Specified conditions
Junction temperature before surge; Tm;
Reverse peak voltage: 0.5VRRM, 0.8VRRM or VARM when otherwise specified; Forward (non-repetitive) surge current: as per product standard; Maximum impedance of reverse voltage source: should be as small as possible to meet the requirements of item b; Frequency of each surge: one cycle unless otherwise specified; Number of surges: as per product standard;
Measurement limit after test: as per product standard. Test procedure
Set the voltage and current sources to zero.
Mark them by their polarity. Install the module under test into the test bench. And meet its temperature conditions. Adjust the reverse peak voltage displayed on the peak reading meter PV to the specified value.
Adjust the resistor R1 so that the forward surge current displayed on the bee reading meter PA reaches the specified value. c.
JB6307.392
d. Test the chips in the module according to the specified number of times of applying forward surge current. e. After the test, measure the chips in the module one by one according to the inspection items specified in the product standard. If the specified values ​​are met, the tested module is considered to have passed this test.
6.3.1 Purpose
Under specified conditions, test the t value of the chip in the module, or test the t-t curve. 6.3.2 Method Principle
It test is essentially a non-repetitive surge current test with a duration less than the rated sinusoidal flat wave (range of 1 to 10ms). The It value can be obtained by integrating the surge current i with its duration t idt. By changing the duration, the It value at each time point in the half wave can be obtained. Thus, the t curve is obtained (as shown in Figure 7).
'Irsm
(X10°A)
Wherein: IsM—
Surge current peak value, A;
(X10'A·S)
tw(ms)
Figure 7t curve
-P't curve; 2—Issm curve
Figure 8I't test current waveform
Base width of the sine half wave defined in Figure 8; ms
For the 50Hz half cycle (bottom width 10ms) of the working problem, the above formula becomes: (6)
Principle circuit and requirements
JB6307.3-92
t=0.005sm(A*.s)
Figure 93t test circuit
R3--non-inductive resistor for observing forward current; capacitor, inductor, resistor for waveform; surge current waveform according to the following formula. Determined by C, L, and R2. For the decay oscillation waveform, it is determined by formulas (8), (9), and (10): C=0.53
IpsM t
For the sinusoidal waveform, it is determined by formulas (11), (12), and (13): C=0.32
Where: V. The charging voltage of capacitor C, V; IsM·t
to-the bottom width of the sine half wave defined as shown in Figure 8, msIpsM-the peak value of the surge current, A.
C, L, R2-
produces a forward current
peak reading voltmeter.
+*（12）
In order to make the voltage applied to the chip in the test module as low as possible, as an improvement to the circuit, the discharge current of C can be used to pass through the low-voltage transformer first and then through the chip of the test module, so that the voltage of capacitor ℃ can be charged to a higher level, which is conducive to the generation of large current pulses. 6.3.4 Specified conditions
Junction temperature before surge: T or 25℃;
Surge current: The waveform is a half-sine wave, the peak value IrsM is in accordance with the product standard, the bottom width, when a single value of I\ is given, it is 10ms, and when a curve is given, 4 to 5 points (such as 1, 3, 5, 7, 9ms) should be taken between 1 and 10ms; c
Number of surges: should be specified, and the interval between each two times. Determined by thermal equilibrium conditions; no reverse voltage is applied immediately after the surge.
Test procedure
Heat the test module to the specified junction temperature;
Adjust C, L, and R2 so that the chip of the test module passes the surge current IssM with the specified peak value and bottom width (corresponding to the verified Tt value); after the specified number of surges, measure the reverse repetitive peak current and forward peak voltage according to 4.1 and 4.2. If the product standard is met
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