WO2015107498A1 - Commande de puissance par coupure de phase - Google Patents

Commande de puissance par coupure de phase Download PDF

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Publication number
WO2015107498A1
WO2015107498A1 PCT/IB2015/050357 IB2015050357W WO2015107498A1 WO 2015107498 A1 WO2015107498 A1 WO 2015107498A1 IB 2015050357 W IB2015050357 W IB 2015050357W WO 2015107498 A1 WO2015107498 A1 WO 2015107498A1
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Prior art keywords
converter
power
output
current
load
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King Kuen HAU
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Individual
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Priority to CN201580004865.8A priority Critical patent/CN106489303B/zh
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    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
    • H05B45/10—Controlling the intensity of the light
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
    • H05B45/30—Driver circuits
    • H05B45/37—Converter circuits
    • H05B45/3725—Switched mode power supply [SMPS]
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
    • H05B45/30—Driver circuits
    • H05B45/37—Converter circuits
    • H05B45/3725—Switched mode power supply [SMPS]
    • H05B45/382—Switched mode power supply [SMPS] with galvanic isolation between input and output
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
    • Y02B20/30—Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]

Definitions

  • the present invention relates generally to apparatus and methods for AC power control, and more particularly to AC power control by phase cutting.
  • the voltage or current level from the power supply should be appropriate for the load, as a load is usually designed to work properly only within a certain range of voltage or current level.
  • a load is usually designed to work properly only within a certain range of voltage or current level.
  • an incandescent lamp may work properly from a line voltage of a specified magnitude, say 230V or 110V, while an LED lamp requires a driving current of say 300 mA. Deviation from the specified range of voltage or current may give rise to compromised operation efficiency or even destructive damage to the power supply or the load.
  • the load may have been specified to accept DC or AC power, at certain frequency, and with certain waveforms.
  • the incandescent lamp may have been designed for 50/60 Hz sinusoidal voltage supplies, while the LED lamp may have been designed for DC current supplies. Deviation from such specifications may also give rise to compromised operation efficiency or even destructive damage to the power supply or the load.
  • the power supply may need to be loaded properly in order to function normally as intended.
  • An example is the TRIAC (TRIode for Alternating Current) dimmed power supply for electrical lighting, whereby there is a requirement for the TRIAC to be loaded sufficiently to maintain a load current of no less than a holding current threshold in order that the TRIAC remains conducting after being triggered by a pulse at the gate electrode.
  • the minimum holding current is a electrical characteristic of the particular TRIAC used.
  • TRIAC dimmer is a good subject for study in view of the new technological challenges as this old technology is applied to modern electronic devices such as LED lights driven by the Switched-mode Power Supply SMPS, as will be explained below.
  • phase-cut power controllers or simply called phase cutters, which control power by phase cutting, i.e. removing a portion of the sinusoidal waveform of the AC voltage, thus reducing the RMS (Root Mean Square) voltage, hence the power, delivered to the load.
  • Phase cutting may actually be considered as a PWM (Pulse Width Modulation) technique applied specifically to AC power control and is normally required to be synchronized to the AC voltage supply frequency for proper operation.
  • PWM Pulse Width Modulation
  • TRIAC dimmers have originally been designed for resistive loads, the incandescent lamps, and have been very popular for their simple circuitry and low cost. Further, by passing control signal and delivering power to the load through the same electrical path, TRIAC dimmers offer the easiest and cheapest way of installation in the two-wire mode, as illustrated in the circuit diagram of FIG. 1. Naturally, majority of existing residential wiring infrastructure has been installed accordingly for two-wire-mode.
  • the TRIAC dimmer consists of a CR (capacitor-resistor) timing circuit consisting of capacitor CI and resistors R1+R2, and a power switching circuit consisting the diac Dl and TRIAC TR1.
  • a typical example is LED light driven by a switching AC-to-DC converter, which presented a reactive and non-linear load to the phase-cut dimmer. This is a problem for the traditional dimmers as LED light, being promoted for high energy efficiency, might not be drawing sufficient current directly or through the power converter to hold the TRIAC dimmer on conduction when it should.
  • the electronic load may not provide a good circuit path for the timing circuit of the TRIAC dimmer to work properly in the two-wire connection mode, leading to erratic behaviour of the lamp such as flickering, flashing, pop-on, drop-out, etc.
  • three-wire connection mode offers a better solution than the two-wire mode in this regard, this is not feasible in many of the existing residential sites. How to design an LED driver that work properly with the two-wire dimming systems has therefore become of practical and commercial significance nowadays.
  • TRIAC dimmers are classified as “leading edge”, or “forward” phase-cut dimmers, in differentiation from “trailing edge”, or “backward” or “reverse” phase-cut dimmers. These two classes are named according to whether the cut portion is the leading or the trailing part of a single half-cycle of the AC voltage, as shown in FIG. 2 for example. From top to bottom, the first waveform is the line voltage before phase cutting, the second is being leading edge cut by around 90 degrees, while the bottom one is trailing edge cut by around 45 degrees.
  • phase-cut dimmers Apart from the above two classes of phase-cut dimmers, there is yet another class which in each half-cycle cuts the AC power many times, or even at high frequencies. These dimmers are called sinewave dimmers which, due to the complexity in circuit structure and the high cost, are only deployed for high end applications in, for example, TV stations and theatres. These dimmers will however also be compatible to the power controllers disclosed by the present invention.
  • Phase cutting is indeed a simple and straight forward way for AC power control.
  • the "cutting" of phase gives rise to a phenomenon that may lead to problems in the design, namely the very abrupt change of voltage and hence the similarly abrupt change of current that lead to undesirable EMI (Electromagnetic Interference).
  • EMI Electromagnetic Interference
  • an LC filter consisting of inductor LI and capacitor C2 is deployed as shown in FIG. 1 for EMI suppression.
  • a TRIAC dimmer simple LC filter works well with resistive loads such as incandescent lamps.
  • an inductive or capacitive load such as a SMPS (Switched-Mode Power Supply) driving a lighting device.
  • SMPS Switchched-Mode Power Supply
  • the abrupt change of voltage, i.e. high dV/dt in symbolic form, impressed on a capacitive load can create very high current pulses, while abrupt change of current, or high dVdt in symbolic form, impressed on an inductor can create very high voltage pulses.
  • Such high levels of EMI if not suppressed could render the power controller and /or the load device inoperative or even destroyed.
  • a minimum loading current is required generally for powering the phase-cut power controller in two-wire mode, by either leading or trailing edge triggering.
  • a resistive dummy load may need to be connected in parallel to draw sufficient amount of current for proper operation of the phase-cut power controller, as shown in FIG. 3A.
  • the dummy load has three functions: helping to provide the necessary
  • the dummy load may be drawing current from the phase cutter, either directly from the output of the cutter, or through the filter & damper, or through the rectifier, as shown in FIG. 3 A. Neglecting the usually small current bypassed by the Filter and Damper Unit, the total current through the Phase Cutter, identified by Ipcut in the block diagram, is equal to sum of Ismpc, the input current to the Switched-mode Power Converter, and Idummy, the current drawn by the Dummy Load.
  • patent US6452343 is an early patent that deploys dummy load/bleeder for the TRIAC dimmers.
  • the block diagram of FIG. 3B is to illustrate a phase-cut power controlling system with a variable dummy load.
  • the Dummy Load is controlled by a Dummy Load Controller DLC to draw current from the rectifier output.
  • Irect representative of the dimmer output current, is detected and compared to a predetermined current reference represented by Iref by a comparator of finite gain (not shown) inside the Dummy Load Controller DLC.
  • Iref can be a constant or a time-varying voltage, representing say a current value no less than the holding current threshold of the phase cutter (such as TRIAC).
  • any shortfall of the dimmer current represented by Irect from that represented by Iref is amplified by the comparator which will drive the Dummy Load to draw more current from the rectifier output, in parallel with the switch-mode power converter, so as to maintain the current from the phase cutter no less than the predetermined value represented by Iref. At the moments the switch-mode power converter is drawing more current, the Dummy Load will be drawing less, hence less power is wasted.
  • FIG.3B there are other alternative sensing points as represented by dotted lines, for such as dimmer output voltage, switched-mode power converter voltage or current, as are deployed by various control schemes of the prior arts exemplified by the following patents.
  • FIG. 4A to 4C shows the operation principle of various schemes of phase-cut power control in the prior art, for loads powered by switched-mode power converters, just like the case for many LED lights nowadays.
  • Quoting LED light as a typical example of load under phase-cut power control, there are two different approaches in the prior art to power the load through a switched-mode power converter.
  • the first approach is for the switched-mode power converter to generate a current of the magnitude proportional to that (such as the RMS or the average or other measures) of the phase-cut voltage. By altering the magnitude of the phase-cut voltage output, the current through the LED light is altered in proportion, and the light output thereby is controlled accordingly.
  • Vrectdc is a DC voltage representative the magnitude of Vrect, either in RMS or average or any other measures.
  • Vrectdc can also be made representative of the duty cycle (percentage uncut portion) of Vrect.
  • Vrectdc is presented as an instantaneous reference to the positive input of the comparator Comp of finite gain, as Ispcref.
  • Ispc Output current from the Switched-mode Power Converter to the Load is detected as and represented by Ispc.
  • Ispc is compared to Ispcref to generate an error signal Ispcerr which is a feedback signal to drive the switched-mode power converter in a direction so as to reduce this error signal.
  • the second approach is for the switched-mode power converter to generate a constant current (or less desirable, voltage) which is delivered to the LED light in chopped mode at a duty cycle proportional to the magnitude (such as the RMS or the average) of the phase-cut voltage.
  • a duty cycle proportional to the magnitude (such as the RMS or the average) of the phase-cut voltage.
  • the control circuit can be much simplified if duty cycle of the output voltage of the phase-cut dimmer can be accepted as representative of the desired magnitude of power to the LED light.
  • FIG. 4B is a block diagram showing how this approach works.
  • the voltage output from the rectifier represented by Vrect is detected and compared to a low voltage reference represented by Vrectlow by the comparator Comp, the output of which is a square wave Vchop.
  • Vchop is of high voltage level when Vrect is higher than Vrectlow
  • Vchop is of low voltage level when Vrect is lower than Vrectlow, meaning that the duty cycle of Vchop is essentially following that of the voltage output from the phase cutter. Consequently the output from the power switched-mode power converter, either current or voltage, is chopped and delivered to the load in accordance with the phase-cut power controller.
  • the LED lights may flicker at 100/120 Hz to a level discernible to human eyes. This is due to the fact that, compared to an incandescent light, an LED responds to the pulsating driving current with a much lower electro-optical response time.
  • FIG. 4C is a circuit illustrating how this is accomplished. As shown, the rectifier output voltage Vrect is detected and transformed to a DC signal Vrectdc by the DC Sig Gen module such that Vrectdc is
  • Vrectdc can also be made representative of the duty cycle of Vrect.
  • Vrectdc drives the pulse width modulation controller PWM Sig Gen which generates a chopping signal Vchop of a frequency 800 Hz or higher, with a duty cycle proportional to Vrectdc. Consequently the output from the power switched-mode power converter and delivered to the load, either current or voltage, is chopped in accordance with the phase-cut power controller at a frequency high enough to remove the flicker effect.
  • a byproduct benefit is that large inrush current due to the presence of large capacitors is much reduced, so is the need for input current dampers.
  • a further benefit is that, without the large capacitors, the input line current tends to follow more closely with the input line voltage, meaning that high power factor is preserved.
  • the TRIAC dimmer is frequently quoted as an example of a typical phase-cut power controller, because it sets a good example for which all the innovations of the present invention apply.
  • LED light with switched-mode power converter is frequently quoted as an example of a typical reactive load to the phase-cut power controller. It should therefore be understood that despite of limited examples the description of the present invention and the corresponding claims apply where appropriate to any phase-cut power controllers and to any sorts of loads.
  • the objectives of the present invention are to develop a power controlling apparatus and method with the following features: a) The amount of holding/loading current as required by the phase cutter be met with by the switching converter without any extra dummy load/bleeder.
  • the TRIAC dimmer in particular, it is recognized that an independent dummy load/bleeder is not desirable from either cost reduction or energy efficiency point of view. It is proposed that the role of dummy load/bleeder be instead taken up by the switched-mode power converter and the load.
  • the current through the phase cutting power controller (or simply, phase cutter) is continuously monitored to see if the requirement of the minimum bleeding/loading current is met. If it falls short, the converter is driven harder (say through increasing duty cycle of PWM) to increase the input current to the converter, hence the
  • the power delivered to the load is monitored and controlled continuously to a specified power level by driving the converter in the same way as that demanded for the minimum bleeding/loading current. It is fine if the minimum bleeding/loading requirement is met while the specified power of the load is reached. However if the minimum bleeding/loading requirement is not met while the specified power of the load is already reached, driving the converter harder will force a higher power into the load than what is specified by design of the load. To solve this dilemma, the converter is driven harder to increase the bleeding/loading current to meet the requirement of the phase cutter, but at the same time the power delivered to the load will need to be stopped from increasing.
  • phase-cut dimmer As for the way power is controlled by the phase cutter, it is recognized that sometimes it might be necessary to deploy a more sophisticated control scheme for the desired function.
  • a typical example is the control of light by phase-cut dimmer. It is well known that perceived light is affected by iris dilation, a natural reflexive action for adaptation. Therefore low light levels do not appear to human eyes as low as measured by the lighting power. For most light dimmers now in the market, the range of dimming control range is too narrow that light level goes down too quickly as dimmer is turned down towards the low end and light level remains high to dilated pupils at the low end of the dimmer control. To improve, a "square law" function is proposed to be built into one of the embodiments of the present invention so that power delivered to the load is roughly proportional to the square of the average of the output voltage of the phase cutter.
  • an energy feedback scheme is developed to bootstrap up the input voltage to the switch-mode power converter so that converter output power is maintained throughout the valleys of the line voltage without the use of large capacitors for charge storage.
  • Small capacitors in the order of a fraction of microfarads are still needed though for the purpose of EMI filtering.
  • FIG. 1 is a schematic diagram of a TRIAC Dimmer as a typical phase cutter.
  • FIG. 2 is a timing diagram showing the leading and trailing edge dimming waveforms.
  • FIG. 3A is a block diagram of a phase-cut power controlling system with a fixed dummy load.
  • FIG. 3B is a block diagram of a phase-cut power controlling system with a variable dummy load.
  • FIG. 4A is a block diagram of a phase-cut power controlling system with output current control.
  • FIG. 4B is a block diagram of a phase-cut power controlling system with output chopping at 100/120 Hz.
  • FIG. 4C is a block diagram of a phase-cut power controlling system with output chopping at 800
  • FIG. 5A is a block diagram showing the relationship between the phase cutter current and the power conversion efficiency of the switch-mode power converter.
  • FIG. 5B is a block diagram of a dimming system with output chopping at 100 Hz as an embodiment of the present invention
  • FIG. 6 is a circuit diagram of analog-OR as an embodiment of the present invention.
  • FIG. 7A is a schematic diagram showing how efficiency of the switched-mode power converter is reduced by weakening the drive signal to the MOSFET as the power switch
  • FIG. 7B is a schematic diagram showing how the efficiency of the switched-mode power converter is reduced by negative feedback from the source electrode of the MOSFET as the power switch
  • FIG. 7C is a schematic diagram showing how efficiency of the switched-mode power converter is reduced by loading the drain electrode of the MOSFET as the power switch.
  • FIG. 7D is a schematic diagram showing how efficiency of the switched-mode power converter is reduced by negative feedback from the collect electrode of the transistor as the power switch.
  • FIG. 7E is a schematic diagram showing how input current to the switched-mode power converter is increased by transformer coupled regenerative snubbing
  • FIG. 7F is a schematic diagram showing how input current to the switched-mode power converter is increased by capacitor coupled regenerative snubbing.
  • FIG. 8 is a block diagram showing the operation flow for system in FIG. 5
  • FIG. 9 is a block diagram showing the dimming system with output chopping at 800 Hz as an embodiment of the present invention.
  • FIG. 10A is a schematic diagram of a Wide-input-range Efficiency-controlled Switched-mode Power Converter, with regenerative snubbing as an embodiment of the present invention
  • FIG. 10B is a schematic diagram of a Wide-input-range Efficiency-controlled Switched-mode Power Converter, with regenerative snubbing as an embodiment of the present invention
  • FIG. 11A is a timing diagram showing the input and output waveforms of the Wide-input-range Efficiency-controlled Switched-mode Power Converter
  • FIG. 11B is the timing diagram of FIG 11A with time scale expanded to show the details of the charging current pulses for regenerative energy transfer.
  • FIG. 12 is a block diagram showing a dimming system by current (/voltage/power) control as an embodiment of the present invention
  • FIG. 13 is a block diagram showing a dimming system with square law characteristic as an embodiment of the present invention.
  • FIG. 14 is a graph showing the LED dimming curves as achieved by an embodiment of the present invention
  • FIG. 5A is a block diagram illustrating how the phase cutter current is related to the power conversion efficiency of the switch-mode power converter, essential for explanation of the principles of the present invention.
  • circuit (A) Shown by circuit (A) is a Switched-mode Power Converter SMPC connected to the rectifier output at voltage Vrect and drawing current Irect from the rectifier and hence the phase cutter (both not shown).
  • the Switched-mode Power Converter SMPC is represented symbolically by a switch SW, with the output delivering a load current Iload to the load LOAD. Assuming that the power efficiency of the converter is Effpc, the power delivered to the LOAD is Vrect x Irect x Effpc.
  • the input current to the converter i.e.
  • Vrect x Irect Vrect x Iloss + Vrect x Iload
  • Iload Effpc x Irect
  • Circuit (C) of FIG. 5A where STOR is the storage element which may be implemented by capacitor or inductors, or even storage batteries. Under the control of the signal Bleed, power switches (not shown)may also be deployed inside the storage element STOR to process the form of the energy (such as raising the voltage) or to control the flow of energy in appropriate direction and at appropriate time. Shown in Circuit (C) as an example, energy may be passed to a buffer capacitor Cbuf when Vrect falls below a
  • a phase-cut power control system with output chopping as an embodiment of the present invention is shown by the block diagram of FIG. 5B.
  • Bleeding current is actively controlled to satisfy the requirement of the phase cutter for the loading current, the holding current of a TRIAC dimmer as a typical example.
  • Dimming control is through 100/120 Hz chopping as explained with respect to FIG. 4B.
  • a Bleed Controller is introduced to control the input current to the switch-mode power converter in meeting simultaneously the minimum current requirement of the phase cutter and the power requirement of the load.
  • the chopping signal Vchop is applied to the Output Chopper switch, or directly to the Switched-mode Power Converter as indicated by dotted line, as the way shown in FIG. 4B.
  • a capacitor Cf is connected at the input of the power converter for filtering high frequency leakage from the converter, but NOT for filtering the low frequency ripples from the rectifier.
  • the voltage waveform from the rectifier output should not be distorted by the presence of the capacitor Cf in view of the need of generating the chopper signal Vchop therefrom.
  • Irect Current output from the rectifier is detected as signal Irect.
  • Irect is representative of the phase-cut current as the preceding filter & damper and rectifier modules should not by design change the current to any significant extent except the very high frequency components which are of no interest as far as bleeding current is concerned. Irect and the point of measurement as shown are chosen as a matter of design convenience. Any other circuit points that would yield the measure of the phase cutter current may be deployed instead for the purpose.
  • Irect is coupled to a comparator Compl of finite gain and compared to a predetermined reference voltage represented by Irectref.
  • This reference voltage can be a constant or a time-varying voltage, and can be chosen to be representative of the minimum bleeding/loading current required for normal operation of the phase cutter, the threshold holding current in case of a TRIAC dimmer for example.
  • the output of the comparator Compl is Irecterr, an error signal indicative how far Irect falls short of Irectref.
  • the error signal is coupled to the Switch Control Pulse Gen module which generates switching control pulses to drive the Switched-mode Power Converter.
  • the switch control pulses may have a duty cycle proportional to the error signal Irecterr, such that an increase in the error signal raises the duty cycle of the switch control pulses to the power converter, and thus increasing both the input and output current of the converter.
  • Uspc is representative of any one of the output current, voltage or power. Uspc may also be taken after the Ouput Chopper switch as indicated by the dotted line, filtered before coupled to a comparator Comp3 of finite gain. At comparator Comp3, Uspc is compared to Uspcref, a predetermined reference signal representative the required output current, voltage or power. The result of comparison, Uspcerr, is an error signal indicative as how far the converter output Uspc departs from the reference Uspcref, i.e. how much the converter output falls short of the desired output level.
  • the error signal is also coupled to the Switch Control Pulse Gen module which generates switching control pulses to drive the Switched-mode Power Converter.
  • the Switch Control Pulse Gen module which generates switching control pulses to drive the Switched-mode Power Converter.
  • analog-OR gate By the operation nature of analog-OR gate, any one of the two inputs with a higher positive signal level dominates the output of the analog-OR gate.
  • a two-input analog-OR gate can be implemented simply by two diodes with the two cathodes of the diodes connected together as the output of the gate, or by one diode and one resistor with the cathode of the diode connected to the resistor as the output.
  • analog-OR gates so formed have non-linearity error due to the non-linear characteristic of the diodes.
  • FIG. 6 a new circuit topology of analog-OR gate is developed as shown in FIG. 6 as an embodiment of the present invention.
  • the design offers the benefit of zero non-linearity error, and each of the inputs can be independently scaled by proper selection of the resistor values.
  • the voltage gain for signal Irecterr is equal to (Rl+R2)/R2
  • voltage gain for signal Uspcerr is (R3+R4)/R4.
  • Uspcerr is larger than Irecterr, meaning that the demand on the power converter for converter output power is stronger than the demand for the minimum bleeding/loading current. Uspcerr will dominate the analog-OR gate, resulting that the target converter output power to the load being reached at an input current exceeding the minimum bleeding/loading current requirement of the phase cutter. This is an acceptable result any way.
  • error signal Uspcerr is inverted and coupled to the converter as a signal Bleed.
  • Signal Bleed is a command for the converter to bleed more, i.e. to raise the converter input current but WITHOUT increasing the power output to the load.
  • the switching elements to dissipate the extra current, and the reactive elements, capacitors and inductors, to store up the energy.
  • FIG. 7A which is a schematic diagram displaying part of a Switched-mode Power Converter, with at least one power switching element, preferably the main switching element.
  • Transistor Ql is such a switching element.
  • signal Bleed is applied to the base of transistor Q2 via resistor R3, turning on Q2. This effectively grounds the common node of resistor R2 and capacitor CI, thus lowering the driving to Ql. Consequently the switch Ql is not completely turned on and off, causing higher volt-drop across the source-drain electrodes of transistor Ql, and longer switching times, resulting in an increased switching loss as heat, right on Ql.
  • FIG. 7B to 7D schematic diagrams of part of Switched-mode Power Converters are displayed in FIG. 7B to 7D, showing how efficiency of the Switched-mode Power Converter is reduced in different ways.
  • efficiency of the Switched-mode Power Converter is reduced by negative feedback from the source electrode of the MOSFET Ql as the main switch, rendering Ql more dissipative in switching
  • FIG. 7C the efficiency of the Switched-mode Power Converter is reduced by loading the drain electrode of the MOSFET Ql with a capacitor CI thus increasing the dissipation on Ql
  • FIG. 7D the efficiency of the Switched-mode Power Converter is reduced by negative feedback from the collect electrode of the bipolar transistor Ql, again rendering Ql more dissipative.
  • the energy transferred from the power source associated with the extra bleeding/loading current can also be stored up as static energy through regenerative snubbing.
  • Ql is the main switch switching the power transformer Tl.
  • Inductor L3 is coupled to the transformer Tl.
  • transistor Q2 is turned on by negative current from comparator IC1, completing the path of L3 and diode Dl for induced current on L3 to flow to the capacitor Cstor .
  • the input current to the Switched-mode Power Converter is increased by transformer coupled regenerative snubbing.
  • the stored energy in Cstor might be consumed at a later time say when supply from the line is at a low level.
  • FIG. 7F shows how input current to the Switched-mode Power Converter is increased by capacitor-coupled regenerative snubbing. Energy is coupled from the drain electrode of the MOSFET Ql as the main switch.
  • FIG. 8 An operation flow chart is provided in FIG. 8. Starting from the state that the phase-cut AC voltage is filtered, damped and rectified, it is queried as whether the rectifier output current, i.e. the phase cutter current, represented by Irect is higher than the reference current represented by Irectref or not. If no, duty cycle of the switch control signal is increased to drive the output Uspc of the switched-mode power converter up.
  • the DC power supply for house-keeping, DCS is powered up, followed by the power up of the Switched-mode Power Converter.
  • Chopping signal Vchop is generated from the phase-cut voltage, and power output from the converter is chopped and delivered to the load.
  • FIG. 9 is a block diagram showing the dimming system with output chopping at 800 Hz or higher as an embodiment of the present invention.
  • the chopping operation is similar to what has been described with regard to FIG. 4C.
  • the chopper signal Vchop is generated from a DC signal Vrectdc proportional to the magnitude of the voltage output of the rectifier, represented by Vrect.
  • WESPCO Wide-input-range Efficiency-controlled Switched-mode Power Converter
  • this is a wide-input-range converter developed to cater for the low level input voltage which is often the case in large phase-cut (high dimming) situations.
  • This is also developed with an intention to eliminate the need of large capacitors.
  • An energy feedback scheme is deployed to bootstrap up the input voltage to the switch-mode power converter so that converter output power is maintained throughout the valleys of the line voltage without the use of large capacitors for charge storage. Small capacitors in the order of a fraction of microfarads are still needed though for the purpose of EMI filtering.
  • FIG. 10A is a schematic diagram of part of a Wide-input-range Efficiency-controlled Switched-mode Power Converter, for illustration of the key portion of the circuit in connection with both regenerative and dissipative snubbing, but omitting the voltage level translation part for clarity.
  • the transistor Q4 is turned on via U2, so that high voltage pulses at the drain electrode of the main switch MOSFET Ql is coupled continuously by capacitor CI to the diode pump formed by rectifying diodes Dl and D2, with charge stored up in capacitor C2.
  • Switch formed by MOSFET Q2 is normally open until switched on by the comparator Ul .
  • Vrectf which is at the output of the filter & damper module which is now positioned after the rectifier module, is coupled to the negative input of the comparator Ul and compared to a predetermined voltage Vrectmin.
  • Vrectmin is chosen to be the minimum voltage to be maintained as Vrectf. Whenever Vrectf falls below Vrectmin, Ul output goes up and turns on Q2, allowing the charge on C2 to be discharged through the diode D4 to the storage capacitor Cstor. As Cstor is charged up, Vrectf goes up and Q2 is switched off as soon as Vrectf is higher than Vrectmin. Charging of Cstor by C2 is stopped and Vrectf goes down as Cstor discharges through the primary coil LI of transformer Tl. The cycle repeats as an oscillation until the line voltage is up and Vrectf rises to a level higher than Vrectmin. Consequently Vrectf is maintained always at a level no lower than the predetermined value of Vrectmin.
  • Vb at the non-inverting input of U2 determines the action level of signal Bleed on regenerative snubbing, while the resistors Rl and R2 determines that on dissipative snubbing on the MOSFET switch Ql. Therefore by adjusting Vb, Rl and R2 the relative priority of regenerative and dissipative actions on MOSFET Ql can be altered by design.
  • FIG. 10B is a schematic diagram of a Wide-input-range Efficiency-controlled Switched-mode Power Converter, with regenerative energy transferred to the power input by magnetic coupling as an embodiment of the present invention.
  • inductor L3 is magnetically coupled to the high frequency switching transformer Tl by the action of signal Bleed.
  • C2 is charged up by L3 through diode D2. The operation then follows the same as that described for FIG. 10A.
  • FIG. 11A is a timing diagram showing the input and output waveforms of the Wide-input-range Efficiency-controlled Switched-mode Power Converter as an embodiment of the present invention.
  • the waveform is generated from a circuit operated according to FIG. 10B with only small capacitors. From top to bottom, the first waveform is the rectified line voltage without filtering, the second is the switched charge current from capacitor C2 to capacitor Cstor. The third one is the voltage Vrectf at the input of the power converter. Note that a minimum voltage of around 100 V is maintained. The bottom waveform is the output voltage of the converter at around 31 V for a load current of around 300 mA.
  • FIG. 11B is the timing diagram of FIG. 11A with time scale expanded at around 30 ms to show clearly the charging current pulses for regenerative energy transfer.
  • FIG. 12 is a block diagram showing a dimming system by current (/voltage/power) control as an embodiment of the present invention. Deploying Wide-input-range Efficiency-controlled
  • the operation of circuit is similar to what has been described in FIG. 4A.
  • the output of the converter can be controlled in terms of voltage, current or power by sensing the output Uspc in the respective parameters.
  • FIG. 13 is a block diagram showing a dimming system with square law characteristic as an embodiment of the present invention.
  • the rectifier output voltage Vrectf filtered and damped, is detected and transformed to a DC signal Vrectdc by the DC Sig Gen module such that Vrectdc is representative the magnitude of Vrect, either in RMS or average or any other measures.
  • Vrectdc can also be made representative of the duty cycle of Vrect.
  • Vrectdc is presented as an instantaneous reference to the positive input of the comparator Comp3 of finite gain, as Ispcref.
  • Signal Uspcerr output of Comp3 is responsible for controlling the output of the Wide-input-range Efficiency-controlled Switched-mode Power Converter WESPCO via the analog-OR gate and the Switch Control Pulse Gen module. Signal Uspcerr is also inverted to become signal Bleed for ensuring that the converter output is still in control despite of a conflicting need to satisfy the bleeding/loading requirement of the phase-cut power controller.
  • Vrectdc is also presented to the Chopper Controller module for generating a chopper signal Vchop to chop the output of the converter WESPCO at a duty cycle in proportion to the magnitude of the phase-cut voltage.
  • Vrectdc Kl*(l-cos(Alpha))/2
  • Kl is a scaling factor proportional to the peak value of the sinusoidal input line voltage before phase cutting.
  • Alpha is the angle of conduction of the phase cutter.
  • power delivered to the load is proportional to the square of the average voltage from the phase-cut power controller.
  • Circuit arrangement as described provides flexibilities for further adjustments of the "dimming' characteristics of the phase-cut power controllers as needed by the application. For example, should the signal Uspc be made representative of the average output voltage or current of the converter WESPCO, while Vrectdc be made the average of the phase cutter output voltage, the power delivered to the load will be proportional to the third power of the average of the phase-cut output voltage. Further variations dimming characteristics are possible through arrangements of special signal processing of the phase-cut output voltage for the control of the power controller.

Landscapes

  • Dc-Dc Converters (AREA)
  • Circuit Arrangement For Electric Light Sources In General (AREA)

Abstract

L'invention concerne un appareil de commande de puissance pour commander le courant électrique délivré à une charge par une source d'alimentation CA à coupure de phase, ledit appareil comprenant : un moyen redresseur convertissant le CA en CC, un convertisseur de puissance en mode commuté avec l'entrée couplée à l'alimentation CC et la sortie couplée à la charge ; et un moyen de commande de puissance pour réguler le courant d'entrée de la source de puissance au convertisseur par la commande de la sortie et de l'efficacité du convertisseur, l'efficacité du convertisseur étant commandée par commande de la perte de dissipative d'au moins un commutateur de puissance du convertisseur ; le convertisseur étant commandé par un contrôleur de purge comprenant une porte OU-analogique.
PCT/IB2015/050357 2014-01-17 2015-01-17 Commande de puissance par coupure de phase Ceased WO2015107498A1 (fr)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105578650A (zh) * 2016-01-13 2016-05-11 矽恩微电子(厦门)有限公司 一种汽车阅读灯led驱动芯片
WO2018184888A1 (fr) * 2017-04-05 2018-10-11 Philips Lighting Holding B.V. Dispositif de commande d'éclairage à del et procédé de commande
WO2019147230A1 (fr) * 2018-01-24 2019-08-01 Hewlett-Packard Development Company, L.P. Contrôleurs de puissance
US11575376B2 (en) 2019-09-27 2023-02-07 Neolith Llc Non-dissipative element-enabled capacitive element driving

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2012016197A1 (fr) * 2010-07-30 2012-02-02 Cirrus Logic, Inc. Alimentation de dispositifs d'éclairage à haute efficacité à partir d'un variateur de type triac
CN202488799U (zh) * 2011-10-14 2012-10-10 欧司朗股份有限公司 照明系统
WO2013027121A1 (fr) * 2011-08-19 2013-02-28 Marvell World Trade, Ltd. Circuit de protection dans des applications de triac
WO2013032592A1 (fr) * 2011-08-31 2013-03-07 Osram Sylvania Inc. Circuit d'attaque pour source de lumière à semi-conducteurs à intensité réglable
US20130234613A1 (en) * 2010-10-04 2013-09-12 Earl W. McCune, Jr. Power Conversion and Control Systems and Methods for Solid-State Lighting

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19548003A1 (de) * 1995-12-21 1997-06-26 Patent Treuhand Ges Fuer Elektrische Gluehlampen Mbh Schaltungsanordnung zur Erzeugung von Impulsspannungsfolgen, insbesondere für den Betrieb von dielektrisch behinderten Entladungen
CN102195292A (zh) * 2010-03-12 2011-09-21 联咏科技股份有限公司 功率因子校正装置
JP6038042B2 (ja) * 2010-12-22 2016-12-07 フィリップス ライティング ホールディング ビー ヴィ 固体照明負荷を駆動するための電力変換器デバイス
CN103152946B (zh) * 2011-01-10 2015-08-05 矽力杰半导体技术(杭州)有限公司 一种高效率的led驱动电路
CN103313466B (zh) * 2012-03-13 2016-03-09 戴乐格半导体公司 用于功率开关晶体管的电流吸收功能的功率耗散监视器

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2012016197A1 (fr) * 2010-07-30 2012-02-02 Cirrus Logic, Inc. Alimentation de dispositifs d'éclairage à haute efficacité à partir d'un variateur de type triac
US20130234613A1 (en) * 2010-10-04 2013-09-12 Earl W. McCune, Jr. Power Conversion and Control Systems and Methods for Solid-State Lighting
WO2013027121A1 (fr) * 2011-08-19 2013-02-28 Marvell World Trade, Ltd. Circuit de protection dans des applications de triac
WO2013032592A1 (fr) * 2011-08-31 2013-03-07 Osram Sylvania Inc. Circuit d'attaque pour source de lumière à semi-conducteurs à intensité réglable
CN202488799U (zh) * 2011-10-14 2012-10-10 欧司朗股份有限公司 照明系统

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105578650A (zh) * 2016-01-13 2016-05-11 矽恩微电子(厦门)有限公司 一种汽车阅读灯led驱动芯片
WO2018184888A1 (fr) * 2017-04-05 2018-10-11 Philips Lighting Holding B.V. Dispositif de commande d'éclairage à del et procédé de commande
CN110506451A (zh) * 2017-04-05 2019-11-26 昕诺飞控股有限公司 Led照明驱动器和驱动方法
JP2020513142A (ja) * 2017-04-05 2020-04-30 シグニファイ ホールディング ビー ヴィＳｉｇｎｉｆｙ Ｈｏｌｄｉｎｇ Ｂ．Ｖ． Ｌｅｄ照明ドライバ及び駆動方法
US11083057B2 (en) 2017-04-05 2021-08-03 Signify Holding B.V. LED lighting driver and drive method
CN110506451B (zh) * 2017-04-05 2022-08-26 昕诺飞控股有限公司 Led照明驱动器和驱动方法
WO2019147230A1 (fr) * 2018-01-24 2019-08-01 Hewlett-Packard Development Company, L.P. Contrôleurs de puissance
US11575376B2 (en) 2019-09-27 2023-02-07 Neolith Llc Non-dissipative element-enabled capacitive element driving
US11955962B2 (en) 2019-09-27 2024-04-09 Neolith Llc Arrangements of non-dissipative elements in non-dissipative element-enabled capacitive element drivers

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