CN105474755A - Spectral shift control for dimmable AC LED lighting - Google Patents

Abstract

Apparatus and associated methods involve operation of an LED light engine in which a relative intensities of selected wavelengths shift as a function of electrical excitation. In an illustrative example, current may be selectively and automatically diverted substantially away from at least one of a number of LEDs arranged in a series circuit until the current or its associated periodic excitation voltage reaches a predetermined threshold level. The diversion current may be smoothly reduced in transition as the excitation current or voltage rises substantially above the predetermined threshold level. A color temperature of the light output may be substantially changed as a predetermined function of the excitation voltage. For example, some embodiments may substantially increase or decrease a color temperature output by a solid state light engine in response to dimming the AC voltage excitation (e.g., by phase-cutting or amplitude modulation).

Description

Spectral shift for tunable optical AC LED illumination controls

PRIORITY CLAIM

The rights and interests of the priority of the U.S. Provisional Patent Application sequence number 61/842,747 that patent application claims on July 3rd, 2013 submits to and based on this, this application is combined in this by reference with its full content.

Technical field

Each embodiment relates generally to the illuminator comprising light-emitting diode (LED).

Background

Power factor is very important for electrical power being delivered to the public utilities of consumer.For two loads requiring actual power level identical, in fact the load with better power factor needs less from utility electric current.The load with 1.0 power factors needs minimum from utility electric current.Public utilities can provide conversion rate with high power factor load to consumer.

Poor power factor can be due to the phase difference between voltage and electric current.Power factor also can be demoted due to the distortion of electric current and harmonic components.In some cases, the current waveform of distortion tends to increase harmonic energy content, and reduces the energy at fundamental frequency place.For sinusoidal voltage waveform, actual power can be sent to load by the energy only at fundamental frequency place.Distorted current waveform can be caused by the nonlinear load of such as rectifier load.Such as, rectifier load can comprise diode (such as, as LED).

LED is the widely used equipment that can carry out throwing light on when being supplied to electric current.Such as, single red LED can provide visible mode of operation to indicate (such as, opening or closing) to equipment operator.As another example, LED may be used for display information in some equipment based on electronic device (e.g., hand-held calculator).LED has also been used in such as illuminator, data communication and Electric Machine Control.

Usually, LED is formed the semiconductor diode with positive pole and negative pole.In theory, ideal diode only incites somebody to action conduction current in one direction.When applying enough forward bias voltage between positive pole and negative pole, conventional current flows through this diode.The forward current flowing through LED can cause photon and hole reconfigure thus release energy in the form of light.

From some LED utilizing emitted light visible wavelength spectrum in.By appropriately selecting semi-conducting material, independent LED can be configured to launch specific color (such as, wavelength), such as, as red, blue or green.

Usually, LED can be created on conventional semiconductor nude film.Independent LED can integrate mutually with other circuit on same nude film, or is packaged into discrete single parts.Usually, the packaging body comprising LED semiconductor element will comprise transparency window and escape out to permit light from packaging body.

The USSN12/785 of the applicant, by providing, 498 and 12/824,215 regulate from being the electric current that compatible AC inputs with light adjusting circuit and equipment that multiple circuit solve these problems, and those disclosures are combined in this completely.Although in the art this kind of circuit solve before problem time be effective, still expect improve these circuit.Specifically, the such as only shown in Figure 23 circuit provided provides the Dead Time what is considered to be in zero crossing place.Specifically, when voltage and current is from when reversed image limit enters positive quadrant (and vice versa) or even waveform is present in positive quadrant completely, when waveform is close to X-axis or zero crossing, electric current according to voltage waveform zero point place flatten and enter and leave zero crossing.In this way, the cycle of zero current or Dead Time is presented in circuit at zero crossing place.

This Dead Time is problematic when associating use with each dimmer or light adjusting circuit.In specific many dimmers, as only for example, silicon controlled dimming device does not keep electric charge and therefore in this Dead Time process, does not have electric current, makes this dimmer be difficult to start at zero crossing place when reactive load is presented.Similar problem also can occur in IGBT type dimmer.Due to the difficulty in some condition in start-up course, the negative effect as flicker and potential appreciable flicker occurs.Therefore, exist in the art and need Dead Time to be minimized in the negative effect at zero crossing place thus improves the performance of LED luminescence component.

Therefore, basic goal of the present invention is to provide light modulation regulating circuit to improve and circuit receives the performance of the Current adjustment that the input based on AC is associated.

General introduction

Multiple device and the method be associated relate to operation LED light engine, and wherein, the relative light intensity of selected wavelength offsets according to electric excitation.In illustrated examples, electric current can by optionally and be automatically substantially shifted out from least one LED in the multiple LED be arranged at series circuit, until this electric current or its periodic excitation voltage be associated reach predetermined threshold level.When this exciting current or voltage rise on this predetermined threshold levels substantially, this transfer current can be reduced smoothly in transition.Can substantially as the colour temperature of the predefined function change light output of this driving voltage.Such as, some embodiments can increase or reduce colour temperature output by solid state light engine in response to carrying out light modulation (such as, by cutting mutually or Modulation and Amplitude Modulation) to this AC voltage drive substantially.

In each example, the selectivity current transfer in LED strip can be expanded input current conduction angle and substantially improves power factor for ACLED illuminator thus and/or reduce harmonic distortion.

Each embodiment can realize one or more advantage.Such as, some embodiments can use such as very simple, low cost and lower powered circuit reduces the harmonic distortion on AC input current waveform substantially.In certain embodiments, can single transistor be comprised for the adjunct circuit realizing the harmonic distortion substantially reduced, or may further include transistor seconds and current sensing element.In some instances, current sensor can be the resistive element that the part of LED current flows through.In certain embodiments, the reduction to remarkable size and manufacturing cost can be realized by being integrated with the one or more LED phases improving control circui by harmonic wave by the harmonic wave improvement circuit on nude film.In some examples, harmonic wave can be improved circuit and integrate to the corresponding controlled LED on common nude film, and the number of process steps manufactured separately required for LED need not be increased.In various embodiments, can such as to use or halfwave rectifier or full-wave rectification improve the harmonic distortion of AC input current substantially for the LED load that AC drives.Some implementations may require few to two transistors and three resistors to provide controlled bypass path to regulate input current thus to improve the power quality in ACLED photo engine.Some implementations can provide the colour temperature of predetermined increase, minimizing or substantial constant on the selected scope of input stimulus.

The details of each embodiment is set forth in the following drawings and specification.Other feature and advantage will become obvious according to specification, drawings and the claims book.

Accompanying drawing briefly describes

Fig. 1 depicts to be had the LED that is configured to full-wave rectifier and is configured for the schematically showing of example A CLED circuit received from the LED strip of the unidirectional current of this rectifier.

Fig. 2 to Fig. 5 depicts representative performance curve and the waveform of the ACLED circuit of Fig. 1.

Fig. 6 to Fig. 9 depicts some exemplary embodiments of the full-wave rectifier illuminator of the selectivity current transfer had for the power quality improved.

Figure 10 to Figure 11 depicts the ACLED string being configured for the halfwave rectifier not having selectivity current transfer.

Figure 12 to Figure 13 depicts the exemplary circuit with the ACLED string being configured for the halfwave rectifier with selectivity current transfer.

Figure 14 to Figure 16 discloses the ACLED topology using conventional (such as, non-LED) rectifier.

Figure 17 to Figure 19 discloses the exemplary embodiment of showing the selectivity current transfer be applied in the ACLED topology of Figure 14.

Figure 20 shows the block diagram for the exemplary means improved at embodiment alignment or the measured power factor of lighting device.

Figure 21 shows the schematic diagram of the exemplary circuit of the LED light engine of harmonic factor and/or the power factor performance with improvement.

Figure 22 shows photo engine circuit for Figure 21 as the chart of the normalization input current of the function of driving voltage.

Figure 23 depicts the voltage waveform of the embodiment of the circuit for Figure 21 and the oscilloscope measurement result of current waveform.

Figure 24 depicts the power quality measurement result of voltage waveform for Figure 23 and current waveform.

Figure 25 depicts the harmonic wave profile of voltage waveform for Figure 23 and current waveform.

Figure 26 shows the schematic diagram of the exemplary circuit of the LED light engine of harmonic factor and/or the power factor performance with improvement.

Figure 27 shows photo engine circuit for Figure 26 as the chart of the normalization input current of the function of driving voltage.

Figure 28 depicts the voltage waveform of the embodiment of the circuit for Figure 26 and the oscilloscope measurement result of current waveform.

Figure 29 depicts the power quality measurement result of voltage waveform for Figure 28 and current waveform.

Figure 30 depicts the voltage waveform of another embodiment of the circuit for Figure 26 and the oscilloscope measurement result of current waveform.

Figure 31 depicts the power quality measurement result of voltage waveform for Figure 30 and current waveform.

Figure 32 shows for the voltage waveform of embodiment and the oscilloscope measurement result of current waveform such as with reference to the circuit of the Figure 26 described by Figure 27 to Figure 29.

Figure 33 depicts the power quality measurement result of voltage waveform for Figure 32 and current waveform.

Figure 34 depicts the harmonic components of the waveform of Figure 32.

Figure 35 depicts the harmonic wave profile of voltage waveform for Figure 32 and current waveform.

Figure 36 and Figure 37 shows curve chart and the data of the experimental measurements of the light output of the photo engine described by reference Figure 27.

Figure 38 shows the schematic diagram of the exemplary circuit of the LED light engine utilizing light modulation regulating circuit.

Figure 39 depicts the voltage waveform of the embodiment of the circuit for Figure 38 and the oscilloscope measurement result of current waveform.

Figure 40 shows the schematic diagram of the exemplary circuit of the LED light engine utilizing light modulation regulating circuit.

Figure 41 depicts the voltage waveform of the embodiment of the circuit for Figure 40 and the oscilloscope measurement result of current waveform.

Figure 42 shows the schematic diagram of the exemplary circuit of the LED light engine utilizing light modulation regulating circuit.

Figure 43 depicts the voltage waveform of the embodiment of the circuit for Figure 42 and the oscilloscope measurement result of current waveform.

Figure 44 shows the schematic diagram of the exemplary circuit of the LED light engine utilizing light modulation regulating circuit.

Figure 45 depicts the voltage waveform of the embodiment of the circuit for Figure 42 and the oscilloscope measurement result of current waveform.

Figure 46 to Figure 48 shows multiple schematic diagrames of light modulation regulating circuit.

Similar reference symbol in each accompanying drawing indicates similar element.

The detailed description of illustrative embodiment

In order to help to understand, on this file population, tissue is as follows.First, in order to help to introduce, each embodiment is discussed, introduce the illuminator using LED to have full-wave rectifier topology referring to figs. 1 through Fig. 5.Secondly, this is introduced to guide and is described some exemplary embodiments of the full-wave rectifier illuminator of the selectivity current transfer had for the power factor ability improved with reference to Fig. 6 to Fig. 9.3rd, with reference to Figure 10 to Figure 13, selectivity current transfer is described in the application of exemplary L ED string being configured for halfwave rectifier.4th, with reference to Figure 14 to Figure 19, the exemplary embodiment turning to and show and use routine (such as, non-LED) rectifier to be applied to the selectivity current transfer in LED strip is discussed.5th, and with reference to Figure 20, this file describes and improve useful various exemplary apparatus and method to calibration or measured power factor in the embodiment of lighting device.6th, this disclosure turns to be checked experimental data and two ACLED photo engine topologys is discussed.A topology is checked with reference to Figure 21 to Figure 25.With reference to the second topology that Figure 26 to Figure 37 checks in three different embodiments (such as, three different subassembly selection).7th, presents describes for combining selectivity current transfer to regulate multiple different topologys of the ACLED photo engine of input current waveform with reference to Figure 38 to Figure 43.

8th, originally disclose with reference to explaining multiple example in all the other accompanying drawings each embodiment as the described herein thus showing how ACLED photo engine can be configured to have selectivity current transfer and provide the expectation in colour temperature to offset to respond the change (such as, light modulation) of input stimulus.Finally, presents relates to the further embodiment of the power quality of improvement, exemplary application and aspect for the ACLED investigation that throws light on.

Fig. 1 depicts to be had the LED that is configured to full-wave rectifier and is configured for the schematically showing of example A CLED circuit received from the LED strip of the unidirectional current of this rectifier.The ACLED described is an example of self-rectifying LED circuit.As indicated by the arrows, conduction current in two quadrants of these rectifiers LED (describing on four sides) only in four AC quadrants (Q1, Q2, Q3, Q4).Load LED (describing diagonally in rectifier) is conduction current in all four quadrants.Such as, in Q1 and Q2 when voltage is just and rises respectively or decline, electric current is conducted through rectifier LED (+D1 to+Dn) and is passed through load LED (+/-D1 is to +/-Dn).In Q3 and Q4 when voltage is negative and decline respectively or rise, electric current is conducted through rectifier LED (-D1 to-Dn) and is passed through load LED (+/-D1 is to +/-Dn).In any one situation (such as, Q1-Q2 or Q3-Q4), input voltage may must reach predetermined conduction angle voltage so that LED starts to conduct effective current.

Fig. 2 depicts the sinusoidal voltage of the excitation across four quadrants with one-period.Q1 across 0 degree to 90 degree (electricity), Q2 across 90 degree to 180 degree (electricity), Q3 across 180 degree to 270 degree (electric) and Q4 across 270 degree to 360 degree (or 0 degree) (electric).

Fig. 3 depicts the illustrative properties curve of LED.In this figure, electric current is depicted as and substantially can ignores below the threshold voltage of about 2.8 volts.Although be representational, this concrete property is for a LED and can be different for other suitable LED, and therefore this certain figures is not intended to for restrictive.This characteristic can change according to temperature.

Fig. 4 depicts the illustrative current waveform of Fig. 2 sinusoidal voltage of the circuit putting on Fig. 1.As directed, for positive half period, conduction angle starts at about 30 degree of places and extends to about 150 electrical degrees.For negative half-cycle, conduction angle extends to about 330 degree (electricity) from about 210 degree (electricity).Each half period is depicted as about only 120 degree of conduction currents.

Fig. 5 depicts the representativeness change of such as current waveform in different Circnit Layout.Such as, can obtain by the quantity reducing series LED the conduction angle (as indicated by curve " a ") increased, this can cause excessive peak current.In described example, can attempt harmonic wave minimizing (as indicated by curve " b ") by introducing extra series resistance, this can increase power consumption and/or reduce light output.

At this, the method and apparatus next described comprises selectivity current transfer circuit, and it advantageously can increase the conduction angle of ACLED and/or improve power factor.Some implementations can be advantageously arranged the balance of the current loading substantially improved in load LED further.

Fig. 6 depicts the first exemplary embodiment of the full-wave rectifier illuminator of the selectivity current transfer had for the power factor ability improved.In this example, there is the additional bypass circuit added across the one group of load LED be connected in series between node A and Node B.This bypass circuit comprises interrupteur SW 1 and sensing circuit SC1.In operation, when SW1 closes, this bypass circuit is activated with at least some LED transfer current in these loads LED.Interrupteur SW 1 controls by sensing circuit SC1, and this sensing circuit selects when activate this bypass circuit.

In certain embodiments, SC1 is operated by sensing input voltage.Such as, when sensed input voltage is lower than threshold value, bypass circuit can be activated with the conduction of boost current in Q1 or Q3, and then keeps electric current conduction at Q2 or Q4.

In certain embodiments, SC1 can be operated by current sensor.Such as, when sensed LED current is lower than threshold value, bypass circuit is activated with the conduction of boost current in Q1 or Q3, and then keeps electric current conduction at Q2 or Q4.

In certain embodiments, the voltage that SC1 derives from commutating voltage by sensing operates.Such as, resitstance voltage divider can be used to perform voltage sensing.In certain embodiments, threshold voltage can be determined the LED of the photoelectrical coupler of the state driving current through control SW1 by the high resistance resistor be coupled.In certain embodiments, can based on the predetermined time delay control SW1 relative to the specified point (such as, zero crossing or voltage peak) in voltage waveform.In this kind of situation, timing can be minimized by the harmonic distortion determining to make from AC power supplies to the current waveform of lighting device supply.

In illustrated examples, by-pass switch SW1 can be arranged mainly to activate in response to the voltage signal exceeding threshold value.Voltage sensing circuit can be equipped to and carry out switching thus the shake controlled near predetermined threshold with predetermined hysteresis.In order to strengthen and/or provide Standby control signal (such as, just in case break down at voltage sensing with in controlling), some embodiments may further include the switching based on auxiliary current and/or timing.Such as, if electric current has exceeded certain predetermined threshold and/or the timing in the cycle exceeds predetermined threshold, and do not receive signal from voltage sensing circuit, so bypass circuit can be activated the harmonic distortion continuing realization minimizing.

In the exemplary embodiment, circuit SC1 can be configured for sensing input voltage VAC.When input voltage is under specific or predetermined value VSET, the output of SC1 is high (very).If SC1 is high (very), so interrupteur SW 1 closed (conduction).Similarly, when voltage is on specific or predetermined value VSET, the output of SC1 is low (vacation).If SC1 is low (vacation), so interrupteur SW 1 disconnects (non-conducting).At fixed current place, VSET is set to the value of the total forward voltage representing rectifier LED (+D1 to+Dn).

In illustrated examples, once voltage be put on ACLED in the beginning in the cycle started with Q1, the output of sensing circuit SC1 will for high and interrupteur SW 1 will be activated (closing).Electric current is conducted by means of only rectifier LED (+D1 to+Dn) and by SW1 via bypass circuit path.After input voltage is increased to VSET, the output of sensing circuit SC1 becomes low (vacation) and interrupteur SW 1 will be deexcitation (disconnection) state by transition.Now, current transition for being conducted through rectifier LED (+D1 to+Dn) and load LED (+/-D1 is to +/-Dn) until SW1 non-conducting substantially in bypass circuit.Sensing circuit SC1 works similarly on positive half period and negative half-cycle, because it can in response to the impedance state of the absolute value control SW1 of VSET.Therefore, substantially the same operation occurs in two half periods (such as, Q1-Q2 or Q3-Q4), except during Q3-Q4, load current will flow through rectifier LED (-D1 to-Dn).

Fig. 7 depicts when using and do not use in Fig. 6 circuit for performing the representative current waveform when bypass circuit path of selectivity current transfer.The illustrative properties waveform with the input current of selectivity current transfer is illustrated in curve (a) and curve (b).Curve (c) represents the illustrative properties waveform of the input current of forbidding selectivity current transfer (such as, the high impedance of bypass path).By walking around load LED (+/-D1 is to +/-Dn), conduction angle can be remarkably increased.In the drawings, conduction angle for the waveform of curve (a, b) is shown in respectively in Q1, Q2 and extends to about 165-170 degree (electricity) from about 10-15 degree (electricity) and extend to about 345-350 degree (electricity) from about 190-195 degree (electricity) among Q3, Q4.

In another illustrative embodiment, SC1 can operate in response to current sensor.In this embodiment, SC1 can sense the electric current respectively flowing through rectifier LED (+D1 to+Dn) or (-D1 to-Dn).When forward current is under that preset or predetermined value ISET, the output of SC1 is high (very).If SC1 is high (very), so interrupteur SW 1 closed (conduction).Similarly, when forward current is on specific or predetermined value ISET, the output of SC1 is low (vacation).If SC1 is low (vacation), so interrupteur SW 1 disconnects (non-conducting).ISET can be set to the value of the electric current at the nominal forward voltage place such as represented at rectifier LED (+D1 to+Dn).

The operation of exemplary means will be described now.Once voltage is put on ACLED, the output of sensing circuit SC1 will for high and interrupteur SW 1 will be activated (closing).Electric current is conducted by means of only rectifier LED (+D1 to+Dn) and by SW1 via bypass circuit path.After forward current is increased to threshold current ISET, the output of sensing circuit SC1 becomes low (vacation) and interrupteur SW 1 will be deexcitation (disconnection) state by transition.Now, along with bypass circuit is converted to high-impedance state, current transition is for being conducted through rectifier LED (+D1 to+Dn) and load LED (+/-D1 is to +/-Dn).Similarly, when input voltage is negative, electric current will flow through rectifier LED (-D1 to-Dn).By introducing selectivity current transfer optionally to walk around these loads LED (+/-D1 is to +/-Dn), conduction angle can be increased significantly.

Fig. 8 is shown the input current that provided by resistors in series R3 by driving source (VAC) in response to bypass circuit response and operates the exemplary embodiment of bypass circuit.Resistor R1 is introduced at first Nodes of connecting with load LED strip (+/-D1 is to +/-D18).Base stage and the emitter of R1 and bipolar junction transistor (BJT) T1 are connected in parallel, and the collector electrode of this BJT is connected with the grid of N slot field-effect transistor (FET) T2 and pullup resistor R2.Resistor R2 is connected to the Section Point in LED strip at its opposite end place.The drain electrode of transistor T2 and source electrode are coupled in first node and the Section Point of LED strip respectively.In this embodiment, sensing circuit is automatic biasing and does not need external power source.

In an example implementations, resistor R1 can be set to certain value, and wherein, at predetermined current threshold ISET place, the voltage drop across R1 reaches about 0.7V.Such as, if the approximation that ISET is 15mA, R1 can be estimated from following formula: R=V/I=0.7V/0.015A approximates 46.OMEGA.Once voltage is applied on ACLED, the grid of transistor T2 can become forward biased and by resistor R2 by feed, its value can be set to hundreds of kOMEGA.After input voltage reaches about 3V, switch T1 will be fully closed (activation).Now, electric current flows through rectifier LED (+D1 to+Dn), switch T2 and resistor R1 (bypass circuit).Once forward current reaches about ISET, transistor T1 will tend to the gate source voltage reducing transistor T2, and this will tend to the impedance improving bypass path.In this case, electric current will increase along with input current amplitude and be transitioned into load LED (+/-D1 is to +/-Dn) from transistor T2.Similar situation will repeat in negative half-cycle, except electric current instead will flow through rectifier LED (-D1 to-Dn).

Described by relative to each embodiment, load balance advantageously can reduce asymmetric duty ratio or the duty ratio substantially between balanced rectifier LED and load LED (such as, carry in all four quadrants unidirectional current those).In some instances, this load balance advantageously can reduce scintillation effect further substantially, and this scintillation effect is usually more weak at the LED place with more high duty ratio.

Bypass circuit embodiment can comprise more than one bypass circuit.Such as, when using two or more bypass circuits to walk around selected LED, can realize improving power factor further.

Fig. 9 shows two bypass circuits.SC1 and SC2 can have different threshold values and effectively can improve input current waveform further to realize even higher conduction angle.

The quantity of the bypass circuit of independent ACLED circuit can be such as 1,2,3,4,5,6,7,8,9,10,11,12,13,14 or more (as 15), about 18,20,22,24,26,28 or at least 30, but as far as possible available many arrangements can be comprised to improve power quality.Bypass circuit can be configured for and is shifted out from the LED that single led or any amount of series, parallel as a whole or series/parallel connect by electric current in response to circuit condition.

As shown in the example embodiment of Fig. 6, Fig. 8 and Figure 10, bypass circuit can be applied to the LED in load LED.In some implementations, one or more bypass circuit can be employed with at full-wave rectifier multi-stage selective around one or more LED transfer current.

As we can in the example of fig. 8 seen by, automatic biasing bypass circuit can be realized with several discreet component.In some implementations, bypass circuit can be manufactured with LED on a single die.In certain embodiments, bypass circuit can use discreet component integrally or partly to realize, and/or integrates with one or more LED be associated with one group of bypass LED or whole ACLED circuit.

Figure 10 depicts example A CLED lighting device, and this device comprises the two string LED being configured to half-wave rectifier, and wherein, each LED strip is conducted electricity and thrown light on the half period replaced.Particularly, just group (+D1 to+Dn) conduction current and negative group (-D1 to-Dn) conduction current in Q3 and Q4 in Q1 and Q2.In any one situation (Q1-Q2 or Q3-Q4), as with reference to Fig. 4 discuss, ac input voltage may must reach the threshold stimulus voltage corresponding to respective conductive angle to make LED start to conduct effective current.

Figure 11 depicts typical in encouraging the sinusoidal excitation voltage Vac waveform of the ACLED lighting device of Figure 10.This waveform is substantially similar to reference to that waveform described by Fig. 2.

Some in illustrative methods described herein and device can improve the conduction angle of ACLED significantly with the driving voltage of at least one polarity in periodically alter polarity (such as, sinusoidal AC, triangular wave, square wave).In some implementations, such as driving voltage can be revised by advanced and/or lagging phase modulation, pulse width modulation.Some examples can realize favourable improvement in performance, and wherein, the electric current of load LED balances substantially.

As shown in figure 12, the circuit of Figure 10 is modified to two bypass circuits comprising and adding across at least some LED in these loads LED.First bypass circuit comprises the interrupteur SW 1 controlled by sensing circuit SC1.Second bypass circuit comprises the interrupteur SW 2 controlled by sensing circuit SC2.Each bypass circuit provides bypass path, and this bypass path can be activated and deexcitation respectively by interrupteur SW 1 or SW2.

In illustrated examples, exemplary light engine can comprise the LED of 39 series connection for conducting during the positive half period and negative half-cycle of correspondence.It should be understood that any suitable combination that can use series and parallel connections LED.In various implementations, the quantity of LED selected and arrange can be the function of such as light output, electric current and voltage specification.In some region, rms (root mean square) line voltage can be about 100V, 120,200,220 or 240 volts.

In the first illustrative embodiment, activate by-pass switch in response to input voltage.SC1 can sense input voltage.When voltage is under specific or predetermined value VSET, the output of SC1 is high (very).If SC1 is high (very), so SW1 closed (conduction).Similarly, when voltage is on particular value or predetermined threshold VSET, the output of SC1 is low (vacation).If SC1 is low (vacation), so interrupteur SW 1 disconnects (non-conducting).Such as, at setting electric current place, VSET is configured to the value of total forward voltage of all LED represented outside the LED walked around by bypass circuit.

The operation of this device will be described now.Once voltage is put on ACLED, the output of sensing circuit SC1 will for high and interrupteur SW 1 will be activated (closing).Electric current is conducted by means of only (+D1 to+D9) and (+D30 is+D39 extremely) and via the first bypass circuit.After input voltage is increased to VSET, the output of sensing circuit SC1 becomes low (vacation) and interrupteur SW 1 will be deactivated (disconnection).Now, electric current is by transition for being conducted through all LED (+D1 to+D39), and the first bypass circuit is high resistant (such as, non-conducting substantially) state by transition.

Substantially as described by with reference to positive LED group, identical process will at input voltage for repeating time negative, except load will flow through negative LED group (-D1 to-D30).When input voltage reaches the negative value of VSET, therefore sensing circuit SC2 and interrupteur SW 2 can be activated or deexcitation.

Figure 13 depicts when using and do not use in the circuit of Figure 12 for performing the representative current waveform when bypass circuit path of selectivity current transfer.The illustrative properties waveform with the input current of selectivity current transfer is illustrated in curve (a) and curve (b).Curve (c) represents the illustrative properties waveform of the input current of forbidding selectivity current transfer (such as, the high impedance of bypass path).Substantially, described by reference Fig. 7, the selectivity current transfer technology of this example can increase conduction angle significantly.By walking around LED (+D10 to+D29) and (-D10 to-D29) respectively, conduction angle can be increased significantly.

In the second illustrative embodiment, by-pass switch SW1, SW2 can be activated in response to input voltage sensing signal.SC1, SC2 sense the electric current flowing through LED (+D1 to+D9) and (+D30 to+D39) respectively.When forward current is under particular value or predetermined threshold ISET, the output of SC1 is high (very).If SC1 is high (very), so interrupteur SW 1 closed (conduction).Similarly, when forward current is more than ISET, the output of SC1 is low (vacation).When SC1 is low (vacation), interrupteur SW 1 transition can be off (non-conducting) state.Such as, ISET can be set to the value of approximate representation at the electric current of the summation of nominal forward voltage place LED (+D1 to+D9) and (+D30 is+D39 extremely).

The operation of exemplary means will be described now.Once voltage is put on ACLED, the output of sensing circuit SC1 will for high and interrupteur SW 1 will be activated (closing).Electric current is conducted by means of only LED (+D1 to+D9) and (+D30 is+D39 extremely) and via bypass circuit.After forward current is increased to ISET, the output of sensing circuit SC1 becomes low (vacation) and interrupteur SW 1 will be deactivated (disconnection).Now, electric current can transition for being conducted through LED (+D1 to+D39) and SW1 non-conducting substantially in the first bypass circuit.Similarly, when input voltage declines and electric current falls substantially lower than ISET, so interrupteur SW 1 will be activated and electric current can be transferred at least partially flow through by-pass switch SW1 instead of these LED (+D10 to+D29).

Substantially similar process will occur, except load current will flow through negative group and/or second bypass circuit of LED when input voltage is negative.

In certain embodiments, load balance advantageously can reduce scintillation effect (if any).As applicable, scintillation effect can be reduced by the duty ratio of increase LED and/or conduction angle usually.

Can operate to use selectivity current transfer technology not to be restricted to the embodiment only with a bypass circuit to regulate the bypass circuit of electric current.In order to improve power factor further, some examples can comprise the bypass circuit of accelerating and are arranged in multiple subgroup by these LED.For example, referring at least Fig. 9, Figure 12, Figure 20, Figure 39 or Figure 42-43, the exemplary embodiment with more than one bypass circuit is described.

In some implementations, some bypass circuit embodiments (the exemplary bypass circuit as Fig. 8) can manufacture with the one or more LED in ACLED photo engine on a single die.

Figure 14 depicts exemplary ACLED topology, and it comprises the conventional diode rectifiers for a string LED feed.As shown in figure 14, this exemplary topology comprises full-bridge rectifier and load LED (+D1 to+D39).

Figure 15 shows by the sinusoidal voltage after full-bridge rectifier process.Across the voltage always polarity is unidirectional substantially (such as, just) of LED (+D1 to+D39).

Figure 16 illustrates current waveform, and this current waveform illustrates the operation of the ACLED circuit of Figure 14.Particularly, input voltage must reach predetermined conduction angle voltage so that LED starts to conduct larger electric current.This waveform is substantially similar to reference to that waveform described by Fig. 4.

Figure 17 to Figure 19 discloses the exemplary embodiment of showing the selectivity current transfer be applied in the ACLED topology of Figure 14.

Figure 17 shows the schematic diagram of the ACLED topology of Figure 14, and it comprises the bypass circuit in the part of these LED be applied in load further.

Method and apparatus described herein can improve the conduction angle of ACLED significantly.As shown in figure 17, there is the additional exemplary bypass circuit added across these loads LED.By switch (SW1), bypass circuit is activated and deexcitation.Interrupteur SW 1 is controlled by sensing circuit SC1.

In the first illustrative embodiment, SC1 controls by-pass switch in response to input voltage.SC1 can at node A place sensing input voltage (see Figure 17).When voltage is under specific or predetermined value VSET, the output of SC1 is high (very).If SC1 is high (very), so interrupteur SW 1 closed (conduction).Similarly, when voltage is on specific or predetermined value VSET, the output of SC1 is low (vacation).If SC1 is low (vacation), so interrupteur SW 1 disconnects (non-conducting).In one example, at fixed current place, VSET is set to the value of total forward voltage sum of approximate representation LED (+D1 to+D9) and (+D30 to+D39).

Once voltage is put on ACLED, the output of sensing circuit SC1 will for high and interrupteur SW 1 will be activated (closing).Electric current is conducted by means of only LED (+D1 to+D9) and (+D30 is+D39 extremely) and via bypass circuit.After input voltage is increased to VSET, the output of sensing circuit SC1 becomes low (vacation) and interrupteur SW 1 will be deexcitation (disconnection) state by transition.In this case, electric current can be transmitted to be conducted through LED (+D1 to+D9) and (+D9 to+D29) and (+D30 to+D39).Bypass circuit can transition be non-conducting substantially.Similarly, when input voltage drops to below VSET in Q2 or Q4, interrupteur SW 1 will be activated and electric current will walk around LED (+D10 to+D29).

Figure 18 shows the exemplary effects on input current.By walking around LED group (+D11 to+D29), conduction angle can be increased significantly.

In the second illustrative embodiment, SC1 controls by-pass switch in response to current sense.SC1 is just sensing the electric current respectively flowing through LED (+D1 to+D9) and (+D30 to+D39).When forward current is under specific or predetermined value ISET, the output of SC1 is high (very).If SC1 is high (very), so SW1 closed (conduction).When forward current is on specific or predetermined value ISET, the output of SC1 is low (vacation).If SC1 is low (vacation), so interrupteur SW 1 disconnects (non-conducting).ISET is set to the value of approximate representation at the electric current of the summation of nominal forward voltage place LED (+D1 to+D9) and (+D30 is+D39 extremely).

Once voltage is put on ACLED, the output of sensing circuit SC1 will for high and interrupteur SW 1 will be activated (closing).Electric current is conducted by means of only LED (+D1 to+D9) and (+D30 is+D39 extremely) and via bypass circuit.After forward current is increased to ISET, the output of sensing circuit SC1 becomes low (vacation) and interrupteur SW 1 will be deactivated (disconnection).Electric current is conducted through LED (+D1 to+D9) and (+D30 to+D39) and LED (+D10 to+D29) now.Bypass circuit is non-conductive.Similarly, when electric current drops to below ISET in Q2 or Q4, interrupteur SW 1 will be activated and electric current will walk around LED (+D10 to+D29).

Each embodiment advantageously can provide the minimizing of scintillation effect for full-wave rectification ACLED photo engine, this scintillation effect usually can be more weak for the LED with more high duty cycle operation.

Some embodiments can comprise the more than one bypass circuit be arranged with around one group of LED transfer current.In order to improve power factor further, such as, two or more bypass circuits can be adopted.In some instances, two or more bypass circuits can be arranged so that one group of bypass LED is divided into multiple subgroup.In some other examples, photo engine embodiment can comprise at least two bypass circuits (see such as Fig. 9, Figure 26) be arranged for around two independent LED group selection ground transfer currents.Figure 12 shows the exemplary optical engine comprising two bypass circuits.Such as, at least with reference to Figure 42 and Figure 43, the further embodiment with the photo engine circuit of more than one bypass path is described.

Figure 19 shows the example implementations of the bypass circuit of LED light engine.The transistor T2 be connected in parallel with these LED needing to be walked around is comprised for optionally walking around the bypass circuit 1900 of one group of LED.The grid of transistor T2 controls by pullup resistor R2 and bipolar junction transistor T1.Transistor T1 can be the transistor of any type as known in the art as all crystals pipe disclosed here, includes but not limited to n channel mosfet, p channel mosfet, depletion type MOS FET, includes but not limited to the bipolar junction transistor etc. of SCR (silicon controlled rectifier).Transistor T1 is in response to the voltage of across sense resistor R1, and this sense resistor carries the summation of the transient current by transistor T2 and these LED.As described in detail with further reference to such as Figure 32, because the momentary power voltage and current condition on bypass circuit of putting on changes in level and smooth and continuous print mode, thus the input current between transistor T2 and these LED shift will with respective smoothed and continuous print mode change.

Each embodiment can by the operational light engine with the impedance of integer (such as, 1,2,3) times modulation transistor T2 of line frequency (such as, about 50 or 60Hz).This impedance modulation can relate to linear (such as, continuous print or simulation) mode is by such as applying its saturation region, linear zone and cut-off region to operate the transistor T2 in bypass path on the scope of corresponding circuit condition (such as, voltage, electric current).

In some instances, the operator scheme of transistor can be the function of instantaneous input current level.Such as, at least with reference to Figure 22, Figure 27 or Figure 32, this kind of examples of functions will be described.

Figure 20 shows the block diagram for the exemplary means improved at embodiment alignment or the measured power factor of lighting device.This device is provided in independent voltage or the current threshold place harmonic components for a large amount of configuration testing electric currents of by-pass switch, the ability of measurement power factor that control.In this way, autotest program such as can determine the allocation optimum of one or more by-pass switch rapidly for any lighting device.During the allocation optimum produced can be stored in database and/or is downloaded to the data storage device that is associated with lighting device to be measured.

The device 2000 described comprise with the rectifier 2005 of load in series (its can comprise LED, diode or both), this load comprises accessory module and a string LED for throwing light on.This device comprises analog switch matrix 2010 further, and any node in diode string can be connected to the terminal of any by-pass switch in multiple by-pass switch by this analog switch matrix.In some instances, can use test pin fixture with the node contact with lighting device to be measured.This device comprises optical sensor 2020 further, and this optical sensor can be configured for the light intensity and/or colour temperature monitoring and exported by lighting device.This device comprises controller 2025 further, this controller receive from power analysis device 2030 power factor (such as, harmonic distortion) data and the information from optical sensor 2020, and be programmed to generate control command to configure these by-pass switches.

In operation, controller sends order the selected node of lighting device to be connected to the one or more by-pass switches in these by-pass switches.In test environment, by-pass switch may be implemented as relay, reed switch, IGBT or other controllable switch element.Analog switch matrix 2010 provides enabled node the flexibly connecting to multiple available by-pass switch from LED strip.Each also setting in these by-pass switches of controller can disconnect or closed threshold condition at its place.

Controller 2025 can access the program 2040 with many executable instructions, and upon being performed, these instructions cause controller to operate multiple by-pass switch with the multiple combinations providing by-pass switch to arrange.In certain embodiments, controller 2025 can perform this program with many instructions to receive the predetermined threshold voltage levvl be associated with any or all switches in these by-pass switches.

Such as, controller 2025 can carry out operating to cause a switch selected in these by-pass switches in low resistance state and dynamically transition between resistance state.In some instances, when the driving voltage applied is through predetermined threshold voltage, controller 2025 can cause transition.In some instances, when input current is through predetermined threshold electric current and/or when meeting one or more time-based condition, controller 2025 can cause transition.

By evaluation circuits performance by rule of thumb under each parameter area, some implementations can identify the configuration by meeting one group of regulatory specifications.For example but without limitation, specification can comprise power factor, total harmonic distortion, efficiency, light intensity and/or colour temperature.

For each configuration meeting specific criteria, one or more value at cost can be determined (such as, based on component costs, manufacturing cost).As illustrated examples, can comprising two bypass paths, need one group of LED and two bypass circuit walked around by each bypass circuit configuration in identify least cost or optimumly export configuration.Each path can be characterized as being has specific impedance operator in each bypass circuit.

With reference to Figure 21 to Figure 37, experimental result is described.Experimental measurements is collected to regulate multiple illustrative embodiment of the electric current of LED light engine for comprising selectivity current transfer.In each measurement, applied driving voltage is set to the 60Hz sinusoidal voltage source at 120Vrms (unless otherwise instructed) place by use Agilent 6812BAC power supply/analyzer.Use the wavy curve figure that the Tyke DP03014 digital fluorescence oscilloscope with DP03PWR module catches input stimulus voltage and current and the power quality parameter calculated.Experiment driving voltage amplitude, waveform and frequency are exemplary, and be not understood to limit.

Figure 21 shows the schematic diagram of the exemplary circuit of the LED light engine of harmonic factor and/or the power factor performance with improvement.In described example, photo engine circuit 2100 comprises full-wave rectifier 2105, and this full-wave rectifier receives the electric excitation from periodic voltage source 2110.Rectifier 2105 provides substantially unidirectional output current to load circuit.Load circuit comprises current-limiting resistor R _input, current-sense resistor R _sensing, be connected to the by-pass switch 2115 of the network with five LED groups (LED group 1-LED group 5).

LED group 1 and LED group 2 are two LED network be connected with the first parallel network.Similarly, LED group 4 and LED group 5 are two LED network be connected with the second parallel network.LED group 3 is the LED network be connected with this two series network between the first parallel network with the second parallel network.By-pass switch 2115 and LED group 3 are connected in parallel.The control circuit being used for operating by-pass switch is not shown, but such as at least with reference to Fig. 6-8, Figure 19 or Figure 26-27, suitable embodiment will be described in further detail.

In operation, when AC input stimulus electric current is lower than predetermined threshold, by-pass switch 2115 is low resistance state in the beginning in each cycle and end.When by-pass switch 2115 is in low resistance state, flow through the input current of LED group 1,2 along the path transfer being parallel to the 3rd LED group by by-pass switch 2115.Therefore, when AC input stimulus 2110 is lower than predetermined threshold, the light launched by photo engine 2100 is only provided by LED group 1,2,4,5 substantially.Use by-pass switch 2115 effectively can reduce the forward threshold voltage starting to draw needed for input current around LED group 3 transfer current at low level of drive place.Therefore, this substantially increases conduction angle relative to the same circuits when not having by-pass switch 2115.

When AC input stimulus electric current rises on predetermined threshold (such as, the forward threshold voltage of LED group 3), by-pass switch can represent the transition of the substantial linear of high-impedance state.When by-pass switch 2115 is transitioned into high-impedance state, the input current flowing through the first and second LED groups also starts to be transitioned into flow through LED group 3 from flowing through by-pass switch 2115.Correspondingly, when AC input stimulus is higher than predetermined threshold, the light launched by photo engine is the combination of the light provided by LED group 1-5 substantially.

In the illustrated examples applied for 120Vrms, LED group 1,2,4,5 can comprise the LED of about 16 series connection separately.LED group 3 can comprise the LED of about 23 series connection.LED group 1,2,4,5 can comprise the LED that transmitting first color exports, and LED group 3 can comprise the LED at least launching the second color output when being driven by basic current.In embodiments, in each LED group and between the quantity of LED, color and/or type can be different.

Lift illustrated examples and without limitation, the first color can be the warm colour (such as, blue or green) that colour temperature is about 2700-3000K substantially.Second color can be the cool colour (such as, white) that colour temperature is about 5000-6000K substantially.Some embodiments advantageously such as can smoothly be transitioned into warm (first) color by having the exemplary lighting apparatus exporting color from cold (second) color by reducing the position of user's input element on dimmer control when the AC excitation being supplied to photo engine is reduced.Such as, with reference to the U.S. Provisional Patent Application sequence number 61/234 being entitled as " color temperature shift thrown light on for tunable optical ACLED controls (ColorTemperatureShiftControlforDimmableACLEDLighting) " that on August 14th, 2009 is submitted to by Grajcar, Figure 20 A to Figure 20 C in 094 describes the example of the circuit for providing gamut, and its full content is combined in this by reference.

In one example, LED group 1,2,4,5 can comprise the LED of about eight, nine or ten series connection, and LED group 3 can comprise about 23,22,21 or 20 LED respectively.Each embodiment can be arranged the diode be connected in series of suitable resistance and proper data amount to use acceptable peak current to provide example to export illumination (such as, in excitation place of peak value AC input voltage) as desired.

These LED in LED group 1-3 may be implemented as packaging body or individual module, or are arranged to sole body and/or many group many LED bodies.In some instances, these independent LED can all export identical chromatogram.In other examples, one or more LED can export the color substantially different from all the other LED.

In certain embodiments, the arranged in parallel of LED group 1,2,4,5 advantageously can reduce imbalance about the aging of LED group 3 relative to the aging of LED group 1,2,4,5 substantially.Such as, this imbalance can be appeared at and can be substantially less than in the situation of the conduction angle of the electric current by first and second groups of LED by the conduction angle of the electric current of bypass LED.Substantially when AC encourages input current just to flow through, LED group 1,2,4,5 conduction current.On the contrary, by-pass switch 2115 be not displaced through the input current of the path in parallel with LED group 3 at least partially time, LED group 3 only conduct forward current.

Rectifier bridge 2105 is depicted as full-bridge to carry out rectification to the single-phase AC excitation provided from voltage source 2110.In this configuration, the positive half period of rectifier bridge 2105 pairs of AC input stimulus and negative half-cycle carry out rectification and have the unidirectional voltage waveform of fundamental frequency for twice input line driving frequency to produce.Therefore, some implementations can reduce appreciable flicker (if any) by increasing LED in the frequency of its place's output bright pulse.In some other embodiments, halfwave rectifier or full-wave rectification can be used.In some instances, rectification can operate from more than one single-phase source (as 3,4,5,6,9,12,15 or more phase sources).

Figure 22 to Figure 25 depicts by the experimental result of operation substantially as collected with reference to illustrated in fig. 21 and described exemplary L ED photo engine circuit.In these experiments, the model of LED is CL-L233-MC13L1, such as, can be purchased from Japanese Citizen Electronics Co., Ltd. (CitizenElectronicsCo., Ltd.).These tests LED group 1,2,4,5 comprises 8 diodes in series connection string separately, and LED group 3 comprises 23 diodes in series connection string.These test component values are designated as the R of 500 ohm _inputwith the R of 23.3 ohm _sensing.

Figure 22 shows photo engine circuit for Figure 21 as the chart of the normalization input current of the function of driving voltage.As depicted, chart 2200 comprises for having selectivity current transfer to regulate the curve chart 2205 of the input current of electric current, and for having the curve chart 2210 of the input current forbidding selectivity current transfer.Curve chart 2210 can be considered to be associated with resistance adjustment at this.

Experimental data illustrates: for similar peak current, reduces to the about 40V (selectivity current transfer) at point 2220 place in the basic effective forward threshold voltage of conducting of its place's beginning from the about 85V (resistance adjustment) at point 2215.This represents that threshold voltage decreases more than 50%.When being applied in rising quadrant and the decline quadrant in each cycle, this corresponds to the basic expansion of conduction angle.

In some instances, curve chart 2205 shows the first flex point 2220, and this first flex point can be the function of LED group 1,2,4,5.Particularly, the voltage at flex point 2220 place can be determined based on the forward threshold voltage of LED group 1,2,4,5, and can be the function of the forward threshold voltage of the operation branch of bridge rectifier 2105 further.

Curve chart 2205 comprises Second Inflexion Point 2225 further.In some instances, Second Inflexion Point 2225 can correspond to the current threshold be associated with bypass control circuit.In embodiments, current threshold can be determined based on such as input current.

The photo engine circuit 2100 that the slope 2230 of the curve chart 2205 between point 2220,2225 has selectivity current transfer with its instruction reciprocal represents substantially lower than the impedance of any impedance represented by curve chart 2210 in this scope.In some implementations, this impedance effect reduced can advantageously promote enhancement mode light output by elevated currents rapidly relative at low driving voltage place, and wherein, LED current is proportional with light output roughly.

Curve chart 2205 comprises the 3rd flex point 2240 further.In some instances, 2240 can correspond on it by the electric current of by-pass switch path substantially close to zero threshold value.Under point 2240, by-pass switch 2115 shifts input current at least partially around LED group 3.

Variable slope shown in the scope 2250 of the curve chart 2205 between point 2225,2240 represents smoothly and the impedance increased continuously in response to the driving voltage increased with its instruction by-pass switch reciprocal in this scope.In some implementations, this motional impedance effect can advantageously promote substantially to flow only through by-pass switch 2115 to (such as, the low harmonics distortion) transition that is level and smooth, substantial linear substantially flowing only through LED group 3 from electric current.

Figure 23 depicts the voltage waveform of the embodiment of the circuit for Figure 21 and the oscilloscope measurement result of current waveform.Curve chart 2300 depicts sinusoidal voltage waveform 2305 and current waveform 2310.Current waveform 2310 presents Head and Shoulders shape.

In this example, take on 2315 and correspond to the electric current flowing through by-pass switch in the scope of lower AC input stimulus level.On the second intermediate range of AC input stimulus level, the impedance of by-pass current increases.When driving voltage continue with the 3rd scope of the second overlapping ranges in substantially smoothly and when rising continuously, voltage across by-pass switch increases above effective forward threshold voltage of LED group 3, and input current to be transitioned into from flowing by-pass switch 2115 in substantially level and smooth and continuous print mode and to flow through LED group 3.At higher AC input stimulus level place, electric current substantially flows only through LED group 3 and does not flow through by-pass switch 2115.

In certain embodiments, the first scope can have a lower limit, and this lower limit is the function of effective forward threshold voltage of the network formed by LED group 1,2,4,5.In certain embodiments, the second scope can have by the lower limit of predetermined threshold limiting voltage.In some instances, the lower limit of the second scope can correspond essentially to predetermined threshold electric current.In certain embodiments, predetermined threshold electric current can be the function of junction temperature (such as, base-emitter node forward threshold voltage).In certain embodiments, the lower limit of the 3rd scope can be the function of effective forward threshold voltage of LED group 3.In certain embodiments, the upper limit of the 3rd scope can correspond to substantially main (such as, to load instantaneous input current at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or at least about 99.5%) flow through the input current of LED group 3.In some instances, the upper limit of the 3rd scope can be the function of the electric current of (such as, be less than 0.5% of the instantaneous input current of load, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9% or be less than about 10%) close to zero substantially flowing through by-pass switch 2115.

Figure 24 depicts the power quality measurement result of voltage waveform for Figure 23 and current waveform.Particularly, measurement result indicated horsepower factor is measured as about 0.987 (such as, 98.7%).

Figure 25 depicts the harmonic wave profile of voltage waveform for Figure 23 and current waveform.Particularly, measured total harmonic distortion is measured as at about 16.1% place.

Therefore, at specified driving voltage place, the embodiment with the LED light engine of selectivity carry circuit advantageously with the power factor operation substantially on 90%, 92.5%, 95%, 97.5% or such as at least about 98%, and can realize the THD substantially under 25%, 22.5%, 20% or such as about 18% simultaneously.Some embodiments of ACLED photo engine can be smoothly and continuously tunable optical substantially further under Modulation and Amplitude Modulation and/or phased modulation on the four corner (such as, 0-100%) of applied driving voltage.

Figure 26 shows the schematic diagram of the exemplary circuit of the LED light engine of harmonic factor and/or the power factor performance with improvement.Each embodiment advantageously can export for the given peak illumination from LED the harmonic distortion producing power factor and/or the minimizing improved.

Photo engine circuit 2600 comprises bridge rectifier 2605 and two LED groups be connected in parallel: LED group 1 and LED group 2, each self-contained multiple LED and being connected to separately between node A and node C.Circuit 2600 comprises the LED group 3 be connected between node C and Node B further.In operation, each in LED group 1,2,3 has substantially a fraction of effective forward voltage that it is applied peak excitation voltage.The combined forward voltage that they and current limiting element combine can control peak forward current.Current limiting element is depicted as resistor R1.In certain embodiments, current limiting element can comprise the one or more elements such as combined, and these elements are selected from fixed resistor, Current Control semiconductor and thermistor.

Photo engine circuit 2600 comprises bypass circuit 2610 further, and the operation of this bypass circuit is with the effective forward turn-on voltage reducing circuit 2600.In embodiments, bypass circuit 2610 can contribute to such as expanding conduction angle by constructing the current waveform of more sinusoidal shape at low AC input stimulus level place, this may tend to power factor and/or harmonic factor useful.

Bypass circuit 2610 comprises its raceway groove and is connected with from node C and around the pass-transistor Q1 (such as, metal-oxide semiconductor (MOS) (MOS) field-effect transistor (FET), IGBT (insulated gate bipolar transistor), bipolar junction transistor (BJT) etc.) of LED group 3 and resistors in series R1 transfer current.The conductivity of raceway groove is modulated by control terminal (such as, the grid of MOSFET).The grid of n channel mosfet Q1 is pulled up voltage by the resistor R2 to node C.In some other embodiments, resistor can be pulled to node A.Can by transistor Q2 (such as, MOSFET, IGBT, junction type FET (JFET), bipolar junction transistor (BJT) etc.) be pulled down to close to the voltage of the source electrode of transistor Q1 and reduces grid voltage.In described example, the collector electrode of transistor Q2 (NPN bipolar junction transistor (BJT)) is configured for load current in response to the base emitter voltage setting up transistor Q2 to regulate grid voltage.Sense resistor R3 connects across the base-emitter of transistor Q2.In various embodiments, the voltage on the grid of transistor Q1 can substantially in response to respective smoothed in input current amplitude and continuous print change and smoothly and change continuously.

Figure 27-29 and Figure 36-37 depicts by the experimental result of operation substantially as collected with reference to illustrated in fig. 26 and described exemplary L ED photo engine circuit.In these experiments, the model of LED group 1,2 is EHP_A21_GT46H (white light), such as, can be purchased from Taiwan hundred million Photoelectron Corp. (EverlightElectronicsCo., LTD.).LED group 3 comprises model EHP_A21_UB01H (blue light), also such as can be purchased from Taiwan hundred million Photoelectron Corp. (EverlightElectronicsCo., LTD.).The LED group 1,2 of these tests comprises 24 diodes of series connection separately, and LED group 3 comprises 21 diodes of series connection.These test component values are designated as the R3 of the R1 of 13.4 ohm, R2 and 806k ohm of 4.2 ohm.

Figure 27 shows photo engine circuit for Figure 26 as the chart of the normalization input current of the function of driving voltage.As depicted, chart 2700 comprises for having selectivity current transfer to regulate the curve chart 2705 of the input current of electric current, and for having the curve chart 2710 of the input current that selectivity current transfer lost efficacy.Curve chart 2710 can be considered to be associated with resistance adjustment at this.

Experimental data illustrates: for similar peak current, reduces to the about 45V (selectivity current transfer) at point 2720 place in the basic effective forward threshold voltage of conducting of its place's beginning from the about 85V (resistance adjustment) at point 2715.This represents that threshold voltage decreases about 45%.When being applied in rising quadrant and the decline quadrant in each rectified sinusoidal cycle, this corresponds to the basic expansion of conduction angle.

In some instances, curve chart 2705 shows the first flex point 2720, and this first flex point can be the function of LED group 1,2.Particularly, the voltage at flex point 2720 place can be determined based on the forward threshold voltage of LED group 1,2, and can be the function of the forward threshold voltage of the operation branch of bridge rectifier 2605 further.

Curve chart 2705 comprises Second Inflexion Point 2725 further.In some instances, Second Inflexion Point 2725 can correspond to the current threshold be associated with bypass circuit 2610.In various embodiments, current threshold can be determined based on the input current of such as transistor Q1, base-emitter node voltage, temperature, current gain and/or transfer characteristic.

The photo engine circuit 2600 that the slope 2730 of the curve chart 2705 between point 2720,2725 has selectivity current transfer with its instruction reciprocal represents substantially lower than the impedance of any impedance represented by curve chart 2710 in this scope.In some implementations, this impedance effect reduced can advantageously promote such as enhancement mode light output by elevated currents rapidly relative at low driving voltage place, and wherein, LED current is proportional with light output roughly.

Curve chart 2705 comprises the 3rd flex point 2740 further.In some instances, 2740 can correspond on it by the electric current of transistor Q1 substantially close to zero threshold value.Under point 2740, transistor Q1 shifts input current at least partially around LED group 3.

Variable slope shown in the scope 2750 of the curve chart 2705 between point 2725,2740 represents smoothly and the impedance increased continuously in response to the driving voltage increased with its instruction transistor Q1 reciprocal in this scope.In some implementations, this motional impedance effect can advantageously promote substantially to flow only through transistor Q1 (such as, low harmonics distortion) transition that is level and smooth, substantial linear to only flowing LED group 3 substantially from electric current.

Figure 28 depicts the voltage waveform of the embodiment of the circuit for Figure 26 and the oscilloscope measurement result of current waveform.Curve chart 2800 depicts sinusoidal voltage waveform 2805 and current waveform 2810.Current waveform 2810 presents Head and Shoulders shape.

In this example, take on 2815 and correspond to the electric current flowing through transistor Q1 in the scope of lower AC input stimulus level.On the second intermediate range of AC input stimulus level, the impedance of transistor Q1 increases.When driving voltage continue with the 3rd scope of the second overlapping ranges in substantially smoothly and when rising continuously, voltage across transistor Q1 increases above effective forward threshold voltage of LED group 3, and input current to be transitioned into from flowing among transistor Q1 in substantially level and smooth and continuous print mode and to flow through LED group 3.At higher AC input stimulus level place, electric current substantially flows only through LED group 3 and does not flow through transistor Q1.

In certain embodiments, the first scope can have a lower limit, and this lower limit is the function of effective forward threshold voltage of the network formed by LED group 1,2.In certain embodiments, the second scope can have by the lower limit of predetermined threshold limiting voltage.In some instances, the lower limit of the second scope can correspond essentially to predetermined threshold electric current.In certain embodiments, predetermined threshold electric current can be the function of junction temperature (such as, base-emitter node forward threshold voltage).In certain embodiments, the lower limit of the 3rd scope can be the function of effective forward threshold voltage of LED group 3.In certain embodiments, the upper limit of the 3rd scope can correspond to substantially main (such as, to load instantaneous input current at least about 95%, 96%, 97%, 98%, 99% or at least about 99.5%) flow through the input current of LED group 3.In some instances, the upper limit of the 3rd scope can be the function of the electric current of (such as, be less than 0.5% of the instantaneous input current of load, 1%, 2%, 3%, 4% or be less than about 5%) close to zero substantially flowing through transistor Q1.

Figure 29 depicts the power quality measurement result of voltage waveform for Figure 28 and current waveform.Particularly, measurement result indicated horsepower factor is measured as about 0.967 (such as, 96.7%).

Figure 30 to Figure 31 depicts by the experimental result of operation substantially as collected with reference to illustrated in fig. 26 and described exemplary L ED photo engine circuit.In these experiments, LED group 1,2,3 comprises model SLHNNWW629T0, such as, can be purchased from Samsung LED Co., Ltd of Korea S (SamsungLEDCo, LTD.).LED group 3 comprises model AV02-0232EN further, such as, can be purchased from the Avago Technologies company (AvagoTechnologies) in California.These tests LED group 1,2 comprises 24 diodes of series connection separately, and LED group 3 comprises 18 diodes of series connection.These test component values are designated as the R3 of the R1 of 47 ohm, R2 and 806k ohm of 3.32 ohm.

Figure 30 depicts the voltage waveform of another embodiment of the circuit for Figure 26 and the oscilloscope measurement result of current waveform.Curve chart 3000 depicts the curve chart of sinusoidal excitation voltage waveform 3005 and input current waveform 3010.Substantially, as described in reference Figure 28, current waveform 3010 presents the Head and Shoulders shape with modified quality threshold, flex point or slope.

Figure 31 depicts the power quality measurement result of voltage waveform for Figure 30 and current waveform.Particularly, measurement result indicated horsepower factor is measured as about 0.978 (such as, 97.8%).

Figure 32 to Figure 35 depicts by the experimental result of operation substantially as collected with reference to illustrated in fig. 26 and described exemplary L ED photo engine circuit.In these experiments, LED group 1,2 comprises the model SLHNNWW629T0 (white light) that such as can be purchased from Samsung LED Co., Ltd of Korea S and the model AV02-0232EN (ruddiness) that such as can be purchased from the Avago Technologies company in California.LED group 3 comprises model C L-824-U1D (white light), such as, can be purchased from Japanese Citizen Electronics Co., Ltd..The LED group 1,2 of test comprises 24 diodes of series connection separately, and LED group 3 comprises 20 diodes of series connection.These test component values are designated as the R3 of the R1 of 715 ohm, R2 and 806k ohm of 23.2 ohm.

Figure 32 shows for the voltage waveform of embodiment and the oscilloscope measurement result of current waveform such as with reference to the circuit of the Figure 26 described by Figure 27 to Figure 29.As depicted, chart 3200 comprises sinusoidal excitation voltage waveform 3205, total input current waveform 3210, the waveform 3215 by the electric current of transistor Q1 and the waveform 3220 by the electric current of LED group 3.

With reference to Figure 27, experimental data shows: for the driving voltage between the first flex point 2720 and Second Inflexion Point 2725, total input current waveform 3210 matches with waveform 3215 substantially.Input current keeps equal substantially with on the scope of the excitation of electric current on Second Inflexion Point 2725 by transistor Q1.But transition flex point 3225 place in the scope of the scope 2750 between point 2725,2740, waveform 3215 starts substantially to be declined by the corresponding speed offset that increases in waveform 3220.Along with driving voltage brings up to voltage corresponding to flex point 2740 by corresponding to the voltage of flex point 3225, waveform 3215,3220 seems to have (such as, linear) slope that is equal and contrary, approximately constant.Driving voltage place on point 2740, is substantially equal to input current waveform 3210 by the waveform 3220 of the electric current of LED group 3.

Figure 33 depicts the power quality measurement result of voltage waveform for Figure 32 and current waveform.Particularly, measurement result indicated horsepower factor is measured as about 0.979 (such as, 97.9%).

Figure 34 depicts the harmonic components of these waveforms of Figure 32.Particularly, harmonic amplitude is only measured as odd harmonic substantially, and the strongest harmonic amplitude is 7 subharmonic at 20% place being less than first-harmonic.

Figure 35 depicts the harmonic wave profile of voltage waveform for Figure 32 and current waveform.Particularly, measured total harmonic distortion is measured as at about 20.9% place.

Therefore, have the ACLED photo engine of selectivity carry circuit embodiment can advantageously be less than 30%, 29%, 28%, 27%, 26%, 25%, 24%, 23%, 22% or be less than about 21% THD operation, and the amplitude of the frequency place harmonic wave wherein, on 1kHz is such as less than about 5% of fundamental frequency amplitude substantially.

Figure 36 and Figure 37 shows curve chart and the data of the experimental measurements of the light output of the photo engine described by reference Figure 27.At applied driving voltage in the experimentation at 120Vrms place, light output is measured with the light loss representing be associated with lens and white (such as, substantially paraboloidal) reflector about 20%.At full driving voltage (120Vrms) place, measured input power is 14.41 watts.

Therefore, when be provided there is about 120Vrms sinusoidal excitation time, have the ACLED photo engine of selectivity carry circuit embodiment can advantageously with every watt at least about 42,44,46,48,50 or about 51 lumens and with at least 90%, 91%, 92%, 93%, 94%, 95% or at least 96% power factor operation.Some embodiments of ACLED photo engine can be smoothly and continuously tunable optical substantially further under Modulation and Amplitude Modulation and/or phased modulation on the four corner (such as, 0-100%) of applied driving voltage.

Figure 36 shows the chart at the calculating composition of the scope place light output of dimming level and total output result of calculation of combination.The selectivity carry circuit of this chart instruction in this implementation provides the light output of level and smooth tunable optical on fundamental voltage scope.In this example, light output surely encourages (such as from quota, 120V in this example) 100% smoothly (such as, continuous print, the dull change) at place reduce to 0% of about 37% (such as, 45V) in this example place in specified excitation.Therefore, use has selectivity current transfer to regulate the usable control range of the amplitude-modulated level and smooth light modulation of some implementations of the ACLED photo engine of electric current can be at least 60% or at least 63% of specified driving voltage.

Figure 37 shows the experimental data at the scope place of dimming level for these calculating compositions of light output and total output result of calculation of combination.LED group 1,2 output is down to the light of at least 5 lumens of less than 50 volts, and LED group 3 output is down to the light of at least 5 lumens of about 90 volts.

Other exemplary circuit are identified in father further and apply for USSN12/824, in 215.That disclosure is combined in this disclosure completely.Although some fathers application has been bonded to during this discloses, the solution presented is not specific to those circuit or the even technology that present LED.This technology can be used in other similarly and take in load-carrying circuit based on AC, and whichever load comprises LED or other light sources.

Additional exemplary circuitry for enhancement mode light modulation is illustrated in Figure 38, Figure 40 and Figure 42.Figure 38 shows the circuit 4000 with AC input 4002, and this AC input received in one embodiment from light adjusting circuit.This AC inputs based on driving voltage and in one embodiment provides electric current via to the MOV (metal oxide varistor) 4005 of rectifying installation 4010 or equivalent rheostat.Utilize bridge rectifier in a preferred embodiment.Then electric current is provided to load 4012, and this load comprises multiple light-emitting diode (LED) 4013.

As known in the art, light modulation regulating circuit 4015 is presented in each circuit to provide shunt access and to comprise the first resistor 4020 of the first transistor 4025 leading to and have drain electrode 4030, source electrode 4035 and grid 4040 at this circuit 4000.The first transistor 4025 is in a preferred embodiment depletion type MOS FET, through n channel mosfet, p channel mosfet, the bipolar junction transistor including but not limited to SCR (silicon controlled rectifier) or the similar transistor that can be utilized when not dropping on outside scope of the present invention similarly.Second resistance 4045 is connected with source electrode 4035 and is placed, and the 3rd resistance 4050 is in parallel with the grid 4040 of the first transistor 4030 places.Therefore, providing in this process of electric current to LED4013, as can be bestly in Figure 39 illustrated, the waveform according to the driving voltage close to zero regulates electric current by light modulation regulating circuit 4015.

As this light modulation regulating circuit 4015 of the use shown in Figure 39 and particularly result of this first resistor, when excitation voltage waveform 4052 is close to zero volt 4053 or zero crossing, electric current is shifted or branch to circuit 4015 from load 4012 or current waveform 4054 is overflowed to the right as shown in the part 4055 and 4060 according to Figure 39.In this way, not only existed but also to be minimized close to the Dead Time of zero crossing 4053 and initial load on light adjusting circuit is minimized.In this way, load 4012 more compatible and be easy to by no matter be silicon controlled dimming device, IGBT light modulator or etc. dimmer control.

Figure 40 illustrates another embodiment again of the circuit 4000 comprising light modulation regulating circuit being similar to Figure 38.In the embodiment of the circuit 4100 of Figure 40, the first resistor 4020 in light modulation regulating circuit is replaced by the diode 4070 in light modulation regulating circuit 4072.As shown in figure 41, there is same effect, wherein, electric current be transferred or branch to regulating circuit 4072 or when voltage waveform 4083 close to when zero volt or zero crossing 4084 as overflowed to the right shown in the part 4075 and 4080 of current waveform 4082.Again, because the Dead Time produced is minimized, provide the added compatibility with dimmer thus.

In another embodiment again of circuit 4000, in Figure 42, circuit 4200 comprises both diode 4085 and the first resistor 4090, and both is connected with the first transistor 4025 in light modulation regulating circuit 4105 and presents.Again, to this of light modulation regulating circuit 4105 be arranged in waveform 4118 in Figure 43 close to when zero volt or zero crossing 4119 as in the part 4110 and 4115 of current waveform 4117 pictorial cause electric current transfer or shunting or effusion.Therefore, at zero crossing 4119 place, Dead Time is minimized or is eliminated, and makes circuit 4000 more compatible with the light adjusting circuit in this area.

Be presented in each circuit in Figure 38, Figure 40 and Figure 42, light modulation regulating circuit 4015,4072 and 4105 is electrically connected to load 4012.Load 4012 can be at USSN12/824, in 215 or the application's foundation any before application in any one in this exemplary circuit presented.Exemplarily, more than first LED4115 can connect with more than second LED4120 and transistor seconds 4125, and this transistor seconds is the depletion type MOS FET worked explicitly with the 4th resistor 4130 in a preferred embodiment.Meanwhile, more than second LED4120 and third transistor 4135 work explicitly, and this third transistor is also preferably the depletion type MOS FET similarly worked explicitly with the 5th resistor 4140.In this way, current waveform 4117 is adjusted to and overlaps with such as the voltage waveform as shown in the chart of Figure 39, Figure 41 and Figure 43.

Therefore, in each circuit presented in Figure 38, Figure 40 and Figure 42, light modulation regulating circuit 4015,4072 and 4105 cause or zero crossing place electric current close to voltage be transferred or shunted or overflowed to the right to minimize or the deadband eliminating time.This cause circuit 4000 be no matter silicon control, IGBT or etc. lighting network control more compatible, the other problems glimmering and be associated with light modulation is minimized.

In another embodiment again as shown in Figure 44, do not utilize rectifier and instead circuit 5000 have AC input 5005, this AC input has the first diode 5010, this first diode allows electric current only to flow on the first direction being electrically connected to transistor 5015, this transistor can be as any transistor contemplated by other embodiments of the present invention or equivalent function equipment, includes but not limited to depletion type MOS FET, through n channel mosfet, p channel mosfet, includes but not limited to the bipolar junction transistor etc. of SCR (scr).Transistor 5015 source electrode 5020 place receive from the first diode 5010 electric current, there is grid 5025 and connect and the drain electrode 5030 in parallel with the second resistance 5040 with the first resistance 5035.

This arrangement can be presented in other circuit or otherwise present.In this embodiment, this arrangement is reversed to adapt to AC input 5005 when not using rectifying installation.Particularly, the second diode 5045 is presented to allow similarly electric current only to flow on first direction and the rightabout in direction that allowed by the first diode 5010.Similarly, transistor seconds 5050 is provided, this transistor seconds can be as any transistor contemplated by other embodiments of the present invention or equivalent function equipment, includes but not limited to depletion type MOS FET, through n channel mosfet, p channel mosfet, includes but not limited to the bipolar junction transistor etc. of SCR (scr).Transistor seconds 5050 source electrode 5055 place receive from the second diode 5045 electric current, there is grid 5060 and connect and the drain electrode 5065 in parallel with the 4th resistance 5075 with the 3rd resistance 5070.

As the result of use light modulation regulating circuit 5000 shown in Figure 45, when excitation voltage waveform 5080 is close to zero volt 5085 or zero crossing, electric current is transferred or is shunted, or current waveform 5090 as overflowed to the right shown in part 5095 and 5100.Then, once voltage waveform 5080 strides across zero crossing 5085 enter reversed image limit, current waveform 5090 is again transferred or is shunted or overflows as shown in by part 5105, and when voltage waveform 5080 is again close to zero crossing 5085, current waveform 5090 as by part 5110 with being transferred shown in figure or being shunted.In this way, not only existed but also to be minimized close to the Dead Time of zero crossing 5085 and initial load on light adjusting circuit is minimized.In this way, circuit 5000 can receive the performance with improvement and be easy to when not using rectifying installation by no matter be silicon controlled dimming device, IGBT light modulator or etc. dimmer control.

Figure 46 to Figure 48 shows the of the present invention multiple embodiment causing these waveforms as provided before.Figure 46 shows the circuit 6000 of reception one input (not shown), and this input is similar to the input provided in the Figure 38 comprising MOV and bridge rectifier.Input supply light modulation regulating circuit 6005 comprise connect with grid 6015 the first resistor 6010, be preferably the first transistor 6020 of MOSFET and be preferably the transistor seconds 6025 of BJT transistor.Second resistor 6030 is connected with the first transistor 6015 and circuit the 3rd resistor 6035 has come.

3rd resistor 6035 is also connected with load 6040, thus makes the 3rd resistor 6035 provide dual-functionality in the circuit.Electric current flow to the first transistor 6015 with or provide in the time course of electric current close to zero crossing place, along with voltage increase, the 3rd resistor 6035 works with the grid 6015 of closed the first transistor thus allows electric current to flow to the first order of load 6040.Then load 6040 is configured to have final stage, and this final stage comprises final transistor 6045 and final resistor 6050, and this final resistor work is with the grid 6055 of closed final transistor.3rd resistor 6035 is connected with final transistor 6050 and is placed, thus making the 3rd resistor 6035 supplement final resistor 6050, the result thus as the dual-functionality of the 3rd resistor 6035 makes the minimizes voltage drop in system and makes the maximizing efficiency of circuit 6000.

In Figure 47, similar to be functionally illustrated in circuit 7000.Again, as Figure 46, provide input for light modulation regulating circuit 7005, wherein, this kind of input can include but not limited to MOV and/or bridge rectifier.Light modulation regulating circuit 7005 has the first transistor 7010 and the first resistor 7015 again.Second and the 3rd resistor 7020 and 7025 be also the part of light modulation regulating circuit 7005.Simultaneously these second and the 3rd resistor 7020 and 7025 be load 7030 not at the same level in and respectfully work to provide input for the multiple light-emitting diodes 7045 being similar to other circuit explicitly with second and third transistor 7035 and 7040.Therefore, be similar to the circuit of Figure 46, second and the 3rd resistor 7020 and 7025 supplement that first resistor 7015 to close the first transistor 7010 when reaching initial threshold voltage.Then each resistor 7020 and 7025 works to close its independently transistor 7035 and 7040 at the places at different levels of circuit similarly in its independently level.Alternatively, can increase by the 4th resistor 7050 to raise the efficiency with comparison with standard circuit.In any case, by make second and the 3rd resistor 7020 and 7025 have functional in light modulation regulating circuit 7005 and independent level, part is minimized and efficiency is maximized thus improves prior art.

Figure 48 shows the circuit of Figure 47, wherein, presents diode 8005 to supplement the first resistor 8015 when turning off the first transistor 8020 in light modulation regulating circuit 8010.Be similar to Figure 47, in the first order of load 8025, transistor seconds 8030 is turned off by the second resistor 8035, and this second resistor also supplements the first resistor 8015 when turning off the first transistor 8020.In addition, provide the second level in load 8025, this second level has third transistor 8040 and the 3rd resistor 8045, and wherein, the 3rd resistor not only turns off third transistor 8040 but also supplement shutoff the first transistor 8020.Again, as previously discussed, optional 4th resistor also can be used with Loss reducing and strengthen efficiency.Therefore again, if the functional of improvement is provided, prior art is strengthened.

In certain embodiments, can single transistor be comprised for the adjunct circuit realizing substantially reducing harmonic distortion, or may further include transistor seconds and current sensing element.In some instances, the resistive element that the part that current sensor can comprise LED current flows through.In certain embodiments, the reduction to remarkable size and manufacturing cost can be realized by being integrated with the one or more LED phases improving control circui by harmonic wave by the harmonic wave improvement circuit on nude film.In some examples, harmonic wave can be improved circuit and integrate to the corresponding controlled LED on common nude film, and the number of process steps manufactured separately required for LED need not be increased.In various embodiments, can such as to use or halfwave rectifier or full-wave rectification improve the harmonic distortion of AC input current substantially for the LED load that AC drives.

Although screw-type socket (it can be referred to as " Edison's spiral " formula socket sometimes) may be used for making the electrical interface of LED light engine and provides mechanical support for LED lamp component, the socket of other types also can be used.Some implementations can use bayonet coupling, this bayonet coupling can represent the pin of the radial directed of one or more conduction, and these pins engage with corresponding slit when LED lamp component is rotated into and carry out electrical with connection that is mechanical support.Some LED lamp component can use such as two or more contact pins, and these contact pins can engages with corresponding socket, and such as, use twisting motion comes not only to make these pins be engaged in socket electrically but also mechanically.For example but without limitation, such as, as in commercially available GU-10 formula lamp, electrical interface can use two pin arrangements.

In some implementations, computer program can comprise many instructions, and when being executed by a processor, these instructions cause processor to adjust colour temperature and/or the light intensity of illumination (it can comprise LED illumination).Colour temperature can be manipulated by composite light device, and this composite light device is by combined for one or more LED and one or more non-LED light source with one or more colour temperature, and each non-LED light source has unique colour temperature and/or light output characteristic.For example but without limitation, multiple colour temperature LED can be combined to provide the color temperature characteristic of expectation on the scope of incentive condition with one or more fluorescent lamp, incandescent lamp, iodine-tungsten lamp and/or mercury vapor lamp source.

Although lighting apparatus is advantageously exported color when can be reduced in the AC excitation being supplied to photo engine and is transitioned into warm colour smoothly from cool colour by some embodiments, other implementations are also possible.Such as, reduce AC input stimulus and can make the colour temperature of LED illumination device such as from relatively warm color displacement to relatively cold color.

In certain embodiments, Material selec-tion and processing can be controlled to manipulate LED colour temperature and other light output parameters (such as, light intensity, direction) to provide the LED by producing the composite attribute expected.Be used to provide the suitable selection of the LED of the colour temperature of expectation and the suitable application of bypass circuit and threshold value to determine combinedly advantageously to permit customizing colour temperature on the scope of input stimulus and change.

In some implementations, the amplitude of driving voltage can such as be modulated by the controlled switching of transformer tapping.Usually, some combinations of tap can be associated from multiple different turn ratio.Such as, can use solid-state or mechanical relay from transformer elementary and/or secondary multiple available tap in carry out selecting to provide the turn ratio closest to expecting AC driving voltage.

In some instances, the AC amplitude that encourages dynamically can be adjusted by adjustable transformer (such as, autotransformer), and this adjustable transformer can provide the level and smooth continuous print adjustment to AC driving voltage on opereating specification.In certain embodiments, AC excitation can be generated by variable velocity/electric press electric generator (such as, being powered by diesel engine).Operate generator can be carried out by controlled speed and/or current parameters to encourage to provide the AC of expectation to LED-based photo engine.In some implementations, AC excitation for photo engine can use well-known solid-state and/or electromechanical means and be provided, these methods can combine AC-DC rectification, DC-DC conversion (such as, voltage raising and reducing type, booster type, voltage-dropping type, regression), DC-AC inversion (such as, half-bridge or full-bridge, transformer-coupled) and/or directly AC-AC conversion.Solid-state switch technology can individually or with suitable modulation strategy (such as, impulse density, pulse duration, pulse-skip, demand etc.) use such as that resonance is (such as in combination, quasi-resonance, resonance), zero crossing (such as, zero current, no-voltage) switching technique.

In an illustrative embodiment, rectifier can receive AC (such as, sinusoidal) voltage and by substantially unidirectional current delivery in the LED module of serial arrangement.When ac input voltage is lower than predeterminated level, by can reduce effective turn-on voltage of LED load around at least one the diode delivered current in these diodes in string.In each example, the selectivity current transfer in LED strip can be expanded input current conduction angle and substantially reduce the harmonic distortion of ACLED illuminator thus.

In various embodiments, multiple apparatus and method advantageously can improve power factor when not introducing the basic resistive dissipation be in series with LED strip.Such as, by the predetermined threshold place that encourages at the AC controlled modulation to one or more current path by selected LED, LED load can provide effective connection forward voltage level of increase for the increase level of AC excitation.For given conduction angle, the effective current-limiting resistance value for the peak value input stimulus electric current maintaining expectation can correspondingly be lowered.

Each embodiment can provide the intensity modulation substantially reduced, and this intensity modulation can by contributing to carry unidirectional current at twice AC input stimulus operating at frequencies LED glimmering (can by the degree of human and animal's perception potentially to it).Such as, full-wave rectifier can provide 100 or 120Hz load current (rectified sine wave) in response to 50 or the excitation of 60Hz input sinusoidal voltage respectively.The load frequency increased produces the corresponding increase in the flicker frequency of illumination, this tend to promote flicker energy towards or exceed it can by the level of the mankind or some animal perception.In addition, some embodiments as the described herein with the photo engine of selectivity current transfer can increase conduction angle substantially, and this can correspondingly reduce during it, do not have light to be exported by LED " Dead Time ".In various embodiments, this operation advantageously can alleviate detectable light amplitude mudulation effect (if any) further.

Exemplary means and the method be associated can relate to conductibility for modulating one or more current path to provide the bypass module of first group of LED, this first group of LED conduction close to minimum export illumination and compare the second group of LED carrying out conducting in maximum output illumination place there is larger conduction angle.In illustrated examples, when AC input stimulus is higher than predetermined threshold voltage or electric current, the conductibility of the bypass path in parallel with a part of second group of LED can be lowered.When input stimulus is lower than predetermined threshold, bypass path can be operated to provide effective turn-on voltage of reduction.For the given maximum output illumination at maximum input stimulus place, bypass module can control by the electric current of selected LED there is the input current waveform of the harmonic distortion of power factor and the minimizing substantially improved.

In each example, current-modulation can expand effective conduction angle of the input stimulus electric current drawn from power supply.

In some instances, modulation can draw constructed input stimulus electric current to be substantially similar to waveform and the phase place of the fundamental frequency of input stimulus voltage, and this can cause harmonic distortion and/or the power factor of improvement.In illustrated examples, the turn-on voltage of LED load can be lowered until encourage input current or its excitation cycle voltage be associated to reach predetermined threshold levels, and substantially declines higher than stopping this turn-on voltage during predetermined threshold levels at exciting current or voltage.

Each embodiment can realize one or more advantage.Such as, some embodiments can be easily combined electrical characteristics and/or the dimming behavior to provide improvement when not redesigning existing LED module.Such as, some embodiments can use a small amount of discreet component combined with existing LED module to be easily implemented.Some implementations can use such as very simple, low cost and the circuit of low-power consumption reduces the harmonic distortion on AC input current waveform substantially.In certain embodiments, can single transistor be comprised for the adjunct circuit realizing the harmonic distortion substantially reduced, or may further include transistor seconds and current sensing element.In some instances, current sensor can be the resistive element that the part of LED current flows through.In certain embodiments, the reduction to significant dimensions and manufacturing cost can be realized by being integrated with the one or more LED phases improving control circui by harmonic wave by the harmonic wave improvement circuit on nude film.In some examples, harmonic wave can be improved circuit and integrate to the corresponding controlled LED on common nude film, and the number of process steps manufactured separately required for LED need not be increased.In various embodiments, can such as to use or halfwave rectifier or full-wave rectification improve the harmonic distortion of AC input current substantially for the LED load that AC drives.

Some embodiments can provide many LED paths in parallel for LED group, for being similar to the root mean square being such as in the electric current carried in that path in specified excitation pro rata across balanced balanced current load among every bar path of all groups.The degradation substantially balanced to these nude films on the useful life that this balance can be implemented advantageously in ACLED photo engine.

Multiple device and the method be associated are passed through substantially to shift exciting currents until this electric current or its excitation cycle voltage be associated reach predetermined threshold levels and substantially reduces the harmonic distortion of exciting current at exciting current or voltage higher than stopping this current transfer during predetermined threshold levels away from the multiple LED be arranged in series circuit.In an illustrative embodiment, rectifier can receive AC (such as, sinusoidal) voltage or unidirectional current is passed to a string LED be connected in series.AC voltage can be worked as lower than the effective connection threshold voltage passing through to reduce around at least one the diode transfer current in these diodes in string diode string during predeterminated level.In each example, the selectivity current transfer in LED strip can be expanded input current conduction angle and substantially reduce the harmonic distortion of ACLED illuminator thus.

This file disclose with for the High Power Factor of the LED illumination System technology relevant with the framework of low harmonics distortion.Relevant example can have with this disclosure co-inventor submit disclosure in find.

In certain embodiments, implementation can with such as to encapsulate and/or other elements of temperature treatment hardware are integrated mutually.Such as, with reference to the multiple examples being described thermal element or other elements that can advantageously integrate mutually with these embodiments described herein by Z.Grajcar at Figure 15 that the U.S. that on November 19th, 2008 submits to openly applies in 2009/0185373Al, its full content is combined in this by reference.

Such as, with reference to by Z.Grajcar on August 14th, 2009 submits be entitled as the harmonic distortion (ReductionofHarmonicDistortionforLEDLoads) of LED load " minimizing ", sequence number is 61/233, Figure 20 A to Figure 20 C of the U.S. Provisional Patent Application of 829 is described in the multiple examples for the technology of the harmonic distortion for the power factor improved and minimizing of gamut LED illumination under AC excitation, and its full content is combined in this by reference.

Such as, with reference to by Z.Grajcar on August 14th, 2009 submits be entitled as " color temperature shift that the ACLED for tunable optical throws light on control (ColorTemperatureShiftControlforDimmableACLEDLighting) ", sequence number is 61/234, each accompanying drawing of the U.S. Provisional Patent Application of 094 describes multiple examples of the technology for light modulation and gamut LED with AC excitation, and its full content is combined in this by reference.

Such as, with reference to reference to by Z.Grajcar on October 22nd, 2009 submit to be entitled as " the complete assembly of LED (LEDDownrightAssembly) ", sequence number is 29/345, each accompanying drawing of the S Design Patent application of 833 describes multiple examples of LED lamp component, and its full content is combined in this by reference.

Each embodiment can in conjunction with one or more electrical interface for carrying out the electrical connection from lighting device to driving source.Such as, at least with reference to by Z.Grajcar on October 27th, 2009 submit to be entitled as " lamp assembly (LampAssembly) ", sequence number is 29/342, Fig. 1-3 or 5 of the S Design Patent application of 578 discloses the example of the electrical interface that can be fully used in certain embodiments in further detail, and its full content is combined in this by reference.

Such as, at least with reference to by Z.Grajcar in being entitled as " framework (ArchitectureforHighPowerFactorandLowHarmonicDistortionLE DLighting) for High Power Factor and low harmonics distortion LED illumination " of submitting on October 28th, 2009, sequence number is 61/255, Fig. 1 of the U.S. Provisional Patent Application of 491, 2, 5A-5B, 7A-7B and 10A-10B describes for ACLED photo engine, exemplary selection carry circuit implementation is shown, comprise the further embodiment of integration module packaging body, its full content is combined in this by reference.

The Dimmable lighting that each embodiment can relate to for animal husbandry is applied.Such as, at least with reference to by Z.Grajcar on October 29th, 2009 submit to be entitled as " LED illumination (LEDLightingforLivestockDevelopment) for animal husbandry development ", sequence number is 61/255, Fig. 3,5A-6C of the U.S. Provisional Patent Application of 855 describe the example of this kind of apparatus and method, and its full content is combined in this by reference.

Some implementations can relate to being installed to by ACLED photo engine to use and have on multiple circuit substrate complying with the LED of pin, and some in these pins can provide basic heat-sinking capability.Such as, at least with reference to by Z.Grajcar on February 12nd, 2010 submit to be entitled as " light-emitting diode component and method (LightEmittingDiodeAssemblyandMethods) ", sequence number is 12/705, Figure 11-12 of the U.S. Patent application of 408 describes the example of this kind of device and method, and its full content is combined in this by reference.

Such as, with reference to by Z.Grajcar on May 24th, 2010 submits be entitled as the harmonic distortion (ReductionofHarmonicDistortionforLEDLoads) of LED load " minimizing ", sequence number is 12/785, Figure 21-43 of the U.S. Patent application of 498 is described in the further example for the technology of the harmonic distortion for the power factor improved and minimizing of gamut LED illumination under AC excitation, and its full content is combined in this by reference.

With reference to these accompanying drawings or otherwise described multiple embodiment in all fields.

An illustrative aspects, a kind of method of the electric current regulated in photo engine comprises the step providing the pair of terminal be adapted to for receiving alter polarity driving voltage.Flow to this to the current amplitude in each terminal of terminal is equal and polarity is contrary.The method comprises the multiple light-emitting diodes (LED) providing and be arranged in first network further.First network is arranged to at least exceeding the forward threshold voltage that is associated with first network in response to driving voltage and conducting described electric current.The method comprises further provides that to be arranged at described first network be multiple LED in the second network of series relationship.This exemplary current control method comprises further to be provided in parallel with described second network and is the step of the bypass path of series relationship with described first network.Another step is in response in the scope of described current amplitude on a threshold current value and increases as the substantially level and smooth of described current amplitude and continuous print function dynamically increases the impedance of this bypass path; Further, permit described electric current and flow through described first network and when described current transfer is left described second network lower than during the forward threshold voltage be associated with second network by voltage drop across bypass path substantially substantially.

In each example, the method can comprise be increased to second network in response to the voltage drop across bypass path forward voltage in a substantially linear fashion described electric current is transitioned into second network from described bypass path.The step of selectivity bypass may further include permits described electric current at driving voltage higher than flowing through described first and second networks during Second Threshold.The step of selectivity bypass may further include substantially smoothly and the current response reduced continuously is substantially level and smooth and increase continuously on Second Threshold and left described second network by from transfer in driving voltage amplitude.The step of selectivity bypass can also comprise the control inputs signal of the amplitude receiving the described electric current of instruction.

This step can comprise the impedance changing the path in parallel with second network, and wherein, this impedance increases monotonously along with increase at least part of scope of driving voltage between first threshold and Second Threshold.This step can relate to further provides the low impedance path in parallel with second network when driving voltage amplitude is in first threshold place or at least part of scope between first threshold with Second Threshold.The step of selectivity bypass can comprise provides the substantially higher impedance path in parallel with second network when driving voltage is substantially on Second Threshold.

In certain embodiments, the method can comprise to the driving voltage received at input terminal place carry out rectification obtain substantially unipolar voltage drive to drive described electric current.The method may further include walks around described electric current in fundamental frequency place selectivity, and this fundamental frequency is the integral multiple of the frequency of driving voltage.This integral multiple can be at least three.

In another illustrative aspects, photo engine can comprise the pair of input terminals be adapted to for receiving alter polarity driving voltage.Flow to this to the current amplitude in each terminal of terminal is equal and polarity is contrary.Photo engine comprises the multiple light-emitting diodes (LED) be arranged in first network, and described first network is arranged to the first threshold for exceeding at least forward threshold voltage amplitude be associated with first network in response to driving voltage and conducts described electric current.Photo engine also comprises the multiple LED in the second network being arranged at and connecting with described first network.Second network is arranged to the Second Threshold of at least summation for exceeding the forward voltage amplitude be associated with first network and the forward voltage amplitude be associated with second network in response to driving voltage and conducts described electric current.It comprises further at driving voltage lower than flowing through first network by permitting current during Second Threshold and substantially current transfer being left second network and optionally walk around the device of second network.

For example but without limitation, this at least with reference to Figure 19,26 and 38-43 the exemplary means being used for selectivity bypass is described.

In certain embodiments, selectivity shunting device can at least part of scope of driving voltage between first threshold and Second Threshold time further permitting current flow through first network substantially current transfer is left second network.Selectivity shunting device can also flow through described first and second networks at driving voltage higher than permitting current during Second Threshold.Selectivity shunting device can operate further and be increased to higher than Second Threshold substantially smoothly and reduce the electric current flowing through shunting device continuously with and continuous print substantially level and smooth in response to driving voltage amplitude.

In some instances, selectivity shunting device can comprise the control inputs of the amplitude in response to electric current.Selectivity shunting device can be exercisable to present the variableimpedance path in parallel with second network, thus variableimpedance is increased monotonously along with increasing at least part of scope of driving voltage between first threshold and Second Threshold.Selectivity shunting device can be exercisable with at least part of scope of driving voltage amplitude between first threshold with Second Threshold time present the low impedance path in parallel with second network.Selectivity shunting device can be exercisable with at driving voltage substantially higher than presenting the substantially higher resistance path in parallel with second network during Second Threshold.

In certain embodiments, photo engine may further include rectifier module the driving voltage received at input terminal place to be converted to unipolar voltage drive thus drive described electric current substantially.

Describe multiple implementation.But, will be appreciated that and can carry out various amendment.Such as, if if with different orders perform disclosed by technology these steps or combine multiple parts of disclosed system in a different manner or supplement these parts with miscellaneous part, so can realize multiple favourable result.Therefore, in the scope of following claims, other implementations are considered.

Claims (7)

1. regulate a method for the electric current in photo engine, step comprises:

There is provided pair of input terminals, this receives one-period driving voltage to input terminal;

Receive and enter this to the electric current with equal amplitude and opposite polarity in each terminal of terminal, described current response flows in this driving voltage;

There is provided the multiple light-emitting diodes (LED) be arranged in a first network, described first network is arranged at least exceed in response to this driving voltage a forward threshold voltage being associated with this first network and conduct described electric current;

The multiple LED be arranged at described first network in the second network being series relationship are provided;

A bypass path in parallel with this second network is provided;

In response to increase in the scope of described current amplitude on a threshold current value as the substantially level and smooth of described current amplitude and continuous print function dynamically increases the impedance of this bypass path; And

Waveform light modulation regulating circuit according to this periodic excitation voltage shifts this electric current from this first network.

2. the method for claim 1, wherein when the waveform of this periodic excitation voltage is transferred close to this electric current during zero volt.

3. the method for claim 1, wherein this light modulation regulating circuit comprises a shunt access, when the waveform of this periodic excitation voltage flows through this shunt access close to electric current during zero volt.

4. method as claimed in claim 3, comprises further as the substantially level and smooth of described current amplitude and continuous print function dynamically increases the step of the impedance of this shunt access.

5. the method for claim 1, wherein this light modulation regulating circuit comprises at least one transistor with a resistor in series.

6. method as claimed in claim 5, wherein, this light modulation regulating circuit comprises at least one diode with this resistor in series further.

7. the method for claim 1, wherein, a resistor in this light modulation regulating circuit is in response to increase in the scope of described current amplitude on a threshold current as the substantially level and smooth of described current amplitude and continuous print function dynamically increases the impedance of this bypass path.