CN202083722U - Semi-passive electronic load capable of programming and simulating characteristic of LED (light emitting diode) - Google Patents

Abstract

The utility model relates to a semi-passive electronic load capable of programming and simulating the characteristic of an LED (light emitting diode), comprising an embedded control module, a basic power circuit module and an LED characteristic simulating circuit module, and the LED characteristic simulating circuit module comprises an LED positive voltage current characteristic wave form sampling circuit, a high-frequency/low-frequency alternating current LED voltage current characteristic separating circuit, a high-frequency changeable gain amplifying circuit, a low-frequency changeable gain amplifying circuit and a high-speed linear drive circuit; and the basic power circuit module comprises a high-speed power circuit, a high-speed low-impedance power circuit and a reading and sampling circuit. Due to the additional arrangement of the LED characteristics simulating circuit module, the embedded control module and the basic power circuit, the semi-passive electronic load not only can meet the test requirement of a common load power source, but also can simulate the work characteristic of the LED load, so that the test on all LED drive power sources and the like can be met, and a test result which is more exact and reliable can be obtained.

Description

The electronic load of a kind of semi-passive emulation LED able to programme characteristic

Technical field:

The utility model belongs to the electronic load field, refers in particular to the electronic load of a kind of semi-passive emulation LED able to programme characteristic.

Background technology:

In the power supply test field, need use electronic load, by the electrical appliance consumed power in the electronic load simulation true environment, cooperate control, the demonstration of PC, corresponding power supply is tested the acquisition test result.

Existing electronic load mainly contains CR, CC, CV, CP, five kinds of mode of operations of pulse in power supply test.And in the test of LED driving power now, the electronic load that is adopted is to design according to the characteristic of ordinary electronic load, these electronic loads specially do not design according to the characteristic of LED itself, so these electronic loads do not simulate the operating characteristic of LED load in the true environment substantially in the middle operating characteristic of testing.Like this, the test result that test obtains to the LED driving power obviously is inaccurate, insecure.

In addition, existing electronic load is because the restriction in element technology and the design will accomplish that high pressure can only be a cost to sacrifice high speed test, brings very big restriction therefore for the development of high-frequency and high-voltage power circuit.

The utility model content:

The purpose of this utility model is to overcome the defective that existing electronic load can't be simulated true LED loaded work piece characteristic, and a kind of semi-passive emulation LED able to programme is provided the electronic load of characteristic.

The utility model realizes that the technical scheme that its purpose adopts is: the electronic load of a kind of semi-passive emulation LED able to programme characteristic, can be used for test to all LED driving powers, it comprises embedded type control module and prime power circuit module, described electronic load also comprises LED characteristic Simulation circuit module, and this LED characteristic Simulation circuit module comprises LED forward volt-ampere characteristic waveform sampling circuit, high and low frequency AC LED volt-ampere characteristic separation circuit, high frequency variable gain amplifying circuit, low frequency variable-gain amplification circuit, high-speed linear driving circuit; Wherein high frequency variable gain amplifying circuit, low frequency variable-gain amplification circuit are relation in parallel; Described prime power circuit module comprises high-speed power circuit and anti-power circuit of High speed and low resistance and retaking of a year or grade sample circuit; Also be provided with the high-speed power adjustable reference unit that is connected with the anti-power circuit of High speed and low resistance in the described prime power circuit module.

In the technique scheme, be provided with the mode switch element that to switch CR pattern, CC pattern, CV pattern, CP pattern, pulse mode, LED pattern respectively in the described embedded type control module.

Adopt technical scheme described in the utility model, on the basis of original electronic load, by adding LED characteristic Simulation circuit module and to embedded type control module, prime power circuit, make the utility model electronic load not only can satisfy the test request of normal load power supply, more can go out the operating characteristic of true LED load by analog simulation, thereby satisfy test to all LED driving powers etc., and obtain more accurately, more reliable test result, provide the more foundation of science to the development of LED driving power.

Description of drawings:

Fig. 1 is the composition frame chart of the utility model electronic load;

Fig. 2 is the testing process block diagram of the utility model electronic load in power supply test is used;

Embodiment:

As shown in Figure 1, the electronic load of semi-passive emulation LED characteristic described in the utility model is on the basis of original embedded type control module 1 and prime power circuit module 2, also set up LED characteristic Simulation circuit module 3, this LED characteristic Simulation circuit module 3 comprises LED forward volt-ampere characteristic waveform sampling circuit 31 (being V-I characteristic waveforms sample circuit), high and low frequency AC LED volt-ampere characteristic separation circuit 32, high frequency variable gain amplifying circuit 33, low frequency variable-gain amplification circuit 34, high-speed linear driving circuit 35; Wherein high frequency variable gain amplifying circuit 33, low frequency variable-gain amplification circuit 34 are relation in parallel; Described prime power circuit module 2 comprises high-speed power circuit 21 and the anti-power circuit 22 of the High speed and low resistance of connecting with high-speed power circuit 21 respectively and voltage, electric current retaking of a year or grade sample circuit 23; Also be provided with the high-speed power adjustable reference unit 24 that is connected with the anti-power circuit 22 of High speed and low resistance in the described prime power circuit module 2.

Comprise PC communication interface 11, primary processor 12 and the multi-path digital/analog converter DAC 13 that is connected with primary processor 12, multi-channel analog/digital converter ADC 14 and hardware such as display screen, keyboard in the described embedded type control module 1, also be provided with the mode switch element 110 that to switch CR pattern, CC pattern, CV pattern, CP pattern, pulse mode, LED pattern respectively.

In conjunction with shown in Figure 2, adopting the utility model electronic load that power supply or LED are driven when testing, can parameter will be set by panel or computer and pass on by communication interface and instruct the LED electronic load, the alternating-current resistance, the LED that singly connect working ressitance and singly meet LED that sets the tested LED forward threshold voltage of LED electronic load, LED connect altogether quantity, average current limit value, ripple current limit value, high-frequency current limit value etc.; Set earlier during at power supply test that tested power supply drawing when inserting carries that a cut-in voltage, constant voltage point, steady current point, constant power points, constant resistance point, voltage limit value require, current limit requires, the ripple current limit value requires, the high-frequency current limit value requires, the ripple voltage limit value requires, the HF voltage limit value requires, the electric current rate of rise, the electric current rate of rise etc.

1, the various patterns of LED forward volt-ampere characteristic and power supply load principle of work:

The output terminal of tested power supply or LED driving is inserted LED electronic load input end.Send into power circuit 21 two ends and LED volt-ampere forward characteristic sample circuit 31 input ends of LED electronic load respectively.When electronic load is operated in the LED pattern, LED is driven the forward VI characteristic low frequency waveform (twice of input terminal voltage frequency of operation of output and LED formation load circuit, direct current is zero) send into the low frequency LED VI low-pass filter circuit of high and low frequency LED forward AC Volt separation circuit 32, the low frequency signal of low frequency frequency is taken out, send into the next stage variable-gain amplification circuit again and go adjusting range; Wherein high frequency variable gain amplifying circuit 33 is also identical with low frequency variable-gain amplification circuit 34 control methods.Interchange with two-way before sending into next stage is superimposed, send into high-speed linear driving circuit 35 and remove to drive the high-speed power circuit, the AC signal that come out sampling this moment removes to control the high-speed power circuit, with after the current characteristics that reaches the high-speed power circuit working and the LED conducting to exchange curve identical.By voltage, electric current retaking of a year or grade sample circuit 23 low-and high-frequency alternating voltage, DC voltage, low-and high-frequency alternating current, the DC current of sampling are sent into analog-to-digital conversion circuit ADC then, then the digital signal of conversion is sent into primary processor 12, calculating wherein by primary processor at last, whether parameter meets setting value.Will be if any the deviation primary processor by D/A conversion circuit DAC 13 output corrections, by mode switch element 110 correction is sent into the amplitude that the low-and high-frequency variable-gain amplification circuit goes to adjust AC controling signal again, reach the LED forward AC characteristic purpose consistent at last with setting value.

When power supply test, directly the analog quantity that sets is sent into high-speed linear driving circuit 35 by mode switching circuit 110 with configuring the power supply test parameter by digital-to-analogue conversion DAC 13, the high-speed power circuit of this moment will go to realize various functions according to switching good mode of operation, and the high-speed power that is connected on a loop also cooperates the high-speed power circuit to switch to constant current, constant voltage, constant-resistance, permanent power, pulse, LED isotype simultaneously.

2, VF and Von principle of work:

Set the cut-in voltage Von of the VF of single-unit LED and power supply at the LED electronic load after, primary processor 12 will be sent a DC precision voltage reference consistent with its setting value by analog digital converting unit DAC, this voltage is sent into high-speed power adjustable reference unit 24 go to control the anti-adjustable DC power supply circuit 22 of High speed and low resistance, make this power circuit go work with the pattern of constant voltage.

3, LED electronic load overall power circuit working principle:

The cold end of high-speed power circuit 21 and the hot end of the anti-adjustable DC power supply circuit 22 of High speed and low resistance are linked together, form a series loop.And the positive output end of tested LED driving or power supply directly inserts the anode of high-speed power circuit 21, tested LED drives or the negative output terminal of power supply directly inserts the negative terminal that High speed and low resistance resists adjustable DC power supply circuit 22, under the situation that the voltage of the anti-adjustable DC power supply circuit 22 of High speed and low resistance is set up, go down to control the loading current of whole tested LED driving or power supply in different patterns then by high-speed power circuit 21.

The advantage of this circuit: when the output voltage of tested LED driving or power supply is lower than the voltage of the anti-adjustable DC power supply circuit 22 of High speed and low resistance, not having any drawing carries and reverse irrigated current, LED is driven or thoroughly startup reliably of power supply, be that present LED drives the most reliable a kind of structure in test electronic load the inside; And for the high-speed power circuit 21 of connecting with the anti-adjustable DC power supply circuit 22 of High speed and low resistance, it mainly is to be operated in that LED drives or power source voltage deducts operating voltage after the anti-adjustable DC power supply circuit 22 of High speed and low resistance, makes 21 sub-fractions of bearing whole test voltage of its high-speed power circuit.So under the situation of high-power device technology restriction now, can be when high-speed power circuit 21 use the low pressure same current, easier realization more speed work.

4, the LED electronic load is principle of work when match system: this equipment can use separately, also can each will cooperate the equipment of finishing test by the industrial computer centralized control, at this once effect and the job order of each equipment in system testing (Fig. 2) are described.At first need a program control power of alterating and direct current supply 41 when test, it can realize different operating voltage and different operating frequency or direct current, and have overvoltage, the under-voltage protection unit 42 in parallel with it is used to monitor the voltage condition of electrical network simultaneously.The dash current of next step access power analysing and measuring instrument 43 responsible analysis tested products, steady current, tangible power, useful power, power factor (PF), harmonic current, no-load power consumption, efficient or the like; Insert spread measurement unit 44 then and go to realize the automatic switchover of multichannel product test simultaneously, next respectively output terminal is inserted tested LED and drive or the power source voltage input end, be allowed to condition at and start work when voltage automatically switches to corresponding measurement products; Output terminal at each test product all inserts the load of a LED artificial electronic able to programme again, is used for test product is loaded according to real loaded work piece pattern; Can also insert a plug-in expansion oscillograph and voltage and current measurement table 45 this moment at the output terminal of measured LED driving or power supply, is used for making things convenient for the user directly to watch measurement result with eyes when test.After above equipment all connects, send the job order that edits in advance by computer, allow the sequencing of each instrument work when measuring by one of them communication interface deactivation, control, the measurement result of gathering each surveying instrument of GPIB, RS232, USB, LAN, test result is noted be used to inquire about test products and whether meet the requirements.

Claims (2)

1. the electronic load of a semi-passive emulation LED able to programme characteristic, can be used in the test to professional LED driving power, it comprises embedded type control module (1) and prime power circuit module (2), it is characterized in that: described electronic load also comprises LED characteristic Simulation circuit module (3), and this LED characteristic Simulation circuit module (3) comprises LED forward volt-ampere characteristic waveform sampling circuit (31), high and low frequency AC LED volt-ampere characteristic separation circuit (32), high frequency variable gain amplifying circuit (33), low frequency variable-gain amplification circuit (34), high-speed linear driving circuit (35); Wherein high frequency variable gain amplifying circuit (33), low frequency variable-gain amplification circuit (34) are relation in parallel; Described prime power circuit module (2) comprises high-speed power circuit (21) and the anti-power circuit of High speed and low resistance (22) and voltage, electric current retaking of a year or grade sample circuit (23); Also be provided with the high-speed power adjustable reference unit (24) that is connected with the anti-power circuit of High speed and low resistance (22) in the described prime power circuit module (2).

2. the electronic load of a kind of semi-passive according to claim 1 emulation LED able to programme characteristic is characterized in that: be provided with the mode switch element (110) that can switch CR pattern, CC pattern, CV pattern, CP pattern, pulse mode, LED pattern respectively in the described embedded type control module (1).

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