CN101044800B - Dimmable lighting system - Google Patents

Abstract

There is disclosed a reactive power controller (RPC) for dimming AC mains lighting systems that use ballasts, for example magnetic ballasts. In one embodiment, a DC/AC converter is used to convert a DC voltage, from a DC voltage source, to an AC voltage that is out of phase with current flowing through the RPC. For example, if the AC voltage is 90 DEG or 270 DEG out of phase with the current then the RPC will appear, to an AC mains lighting system, to be effectively a capacitor or an inductor, thus increasing the effective impedance of the mains supply to the magnetic ballast. The RPC creates a controllable AC voltage at mains frequency, so that the net voltage to the load is adjustable to dim the load. The net voltage is the vectorial sum of the AC mains voltage and the AC voltage created by the RPC. A second RPC may be used to improve the power factor of the AC mains lighting system. The second RPC generates or absorbs the required reactive power of the whole system, so that the input power factor of the AC mains lighting system becomes substantially unity. In an advantageous embodiment, the first and second RPCs are connected to share a common DC voltage source.

Description

Dimmable lighting system

Technical field

The present invention relates to be used to provide (1) high power quality and (2) to be used for single electric light or more generally, comprise the apparatus and method that the light modulation (dimming) of the electrical lighting system of the system that is formed by a plurality of single lamps is controlled.The invention particularly relates to simple general-purpose and non-intrusion type light adjusting system, can upgrade existing lamp and when not in use, on the meaning that light modulating device not have to influence to the normal running of lamp, it is a non-intruding.This device and light-dimming method will maintain any light modulation power level from the high power quality (having the performance that is equivalent to single input power factor) of electric power system.

Background technology

Various dissimilar lamps and illuminator are used in the various application.These comprise incandescent lamp, fluorescent lamp, high-pressure discharge lamp and low-pressure discharge lamp.For aesthetic and power saving reason, in the prior art, made various trials the lamp with brightness adjustment control is provided, so that can adjust the brightness of lamp.

Because many-sided advantage of HID lamp, such as long-life and high luminous efficacy, concerning extensively being used in high-intensity discharge (HID) lamp in the public lighting system, dimming function is particularly useful.Different with incandescent lamp, the warm-up time that high-intensity discharge lamp will be rectificated usually is so that reach full brightness.After cut-out, before restarting them once more, they need the cooling cycle." igniting " again characteristic is the attractive replacement scheme that light modulation is become close simply lamp, does not turn off the light because light modulation requires, therefore avoids the quite long warm-up time of the lamp after igniting again.Develop the dimmable electronic ballast that is used for each lamp although carried out various trials in the prior art, but traditional magnetic ballast remains and is used for high wattage discharge lamp and extensive illuminator, such as the street lamp system the most reliable, durable, cost effectiveness is worthwhile and the selection of advantage.

Light modulation also has other advantages, is used for the flexibility of multiple use area, the safer driving of lamp traffic conditions such as reducing peak power requirements, increasing, and avoids light pollution.The present invention relates to light regulating technology, can regulate the illuminator that forms by a plurality of lamps.Existing non-adjustable optical illumination architecture can convert the illumination system with actual energy-conservation tunable optical to.Do not need to change significantly the lighting electric network.The most important thing is that this technology is not introduced harmonic pollution in the power system keeping providing the principle of " clean environment " power transfer.

Prior art

The existing light-dimming method that is used for existing illuminator comprises and is used for the dimmer based on triac of the incandescent lamp of triac (triac) dimmer compatibility and gaseous discharge lamp, is used for the dimmable electronic ballast of Gas lamp, and the scope that is used to regulate the diverse technology of the lamp that is driven by magnetic ballast.To discuss these prior aries successively.

Dimmer based on triac has been widely used as the light modulation equipment [1] that is used for Edison's type incandescent lamp and some triac dimming fluorescents.Circuit is connected shown in Fig. 1 (a).The triac dimmable device is made up of triac and circuits for triggering, and these circuits for triggering were controlled on the cycle of supply voltage, connects the phase angle of triac.Shown in Fig. 1 (b), by control lag angle (α), can control the output rms voltage, and the power of lamp thus.The control of ac voltage causes adjusting the ability of the brightness of lamp.

Yet the waveform of the power supply input current by the triac dimmable device is decided by delay angle.When delay angle is non-zero, input current will depart from the sine wave shape of supply voltage.When increasing delay-angle, reduce the conduction time of triac.Therefore, input current will be made up of higher harmonic wave component, generate the harmonic wave that will not expect thus and be generated in the electric power system.In addition, because input power factor is the product [2] of displacement factor and distortion factors, but when delay angle was big, input power factor diminished.This is because displacement factor equals to postpone cosine of an angle (if delay angle is big, this displacement factor will diminish), and distortion factors reduces with the current harmonic content increase.The final effect of this low input power factor is to have reactive power flow between ac power supply and illuminator.This reactive power can produce major defect in electric power system.Power factor is more little, and the rated value of converter is big more, and the size of the conductor of transmission of electricity must be bigger.In other words, the cost of generating and transmission of electricity will be bigger.That is that the consumer that always exerts pressure of electric company increases the reason [3] of power factor.

In recent years, exist dimmable electronic ballast as discharge lamp, such as the growing trend of fluorescent lamp and high-intensity discharge (HID) lamp.Dimmable electronic ballast has usually at input and has 4 lines connection configuration.Two connections are used for " live wire " and " zero line " of ac power supply, and two are used for the light modulation level controling signal in addition, and it is the dc signal in 1V-10V normally.The general structure of dimmable electronic ballast is shown in Fig. 2 (a).It is made up of meritorious or reactive factor correcting circuit, high frequency dc/ac transducer and resonant tank circuit.Circuit of power factor correction and dc/ac transducer are by the dc link interconnect of high pressure.The dc/ac transducer is used for driving lamp by resonant tank circuit.Usually with the frequency switching of the resonance frequency that is higher than resonant tank circuit a little.Use resonant tank to provide high pressure so that light lamp and stable lamp current.By the switching frequency of control dc link voltage and/or dc/ac transducer, realize dimming function.Can make input power factor keep high in any power level.Shown in Fig. 2 (b), input current i _AcWaveform be sinusoidal wave and with ac power supply homophase.

The example explanation is used for the typical circuit of the electric ballast of fluorescent lamp in Fig. 2 (c), wherein, and by rectifier rectification ac power supply, by the dc/dc transducer that boosts, realize circuit of power factor correction, by the half-bridge negative circuit, realize the dc/ac transducer, and pass through L _rAnd C _r, form resonant tank circuit.With the level of the peak value that is higher than the ac supply voltage a little, regulate the dc link voltage.If by increasing S ₁And S ₂Switching frequency, regulate lamp, increase L so _rReactance so that reduce the power be transported to lamp.

The electric ballast that is used for fluorescent lamp (low-pressure discharge lamp) has been widely used and has shown that their use has total economic interests [4].Can eliminate the flicker effect of fluorescent lamp and the higher efficient of magnetic ballast that realization is operated than supply frequency (50Hz or 60Hz) with high frequency (usually above 20kHz) operation electric ballast.Therefore, the fluorescent lamp that is driven by electric ballast is exported identical light when comparing with the lamp that is driven by magnetic ballast, consumes still less energy.Yet a major defect of electric ballast is the short relatively life-span (to high quality of products, usually less than 3 to 5 years).Magnetic ballast can be operated more than 10 years usually, and need not replace, and seldom has and have this long-life electric ballast.Simultaneously, inductor core material and winding material are callable, and electric ballast has more poisonous and expendable material.

In HID lantern fair field, it is different using the situation of electric ballast.Electric ballast only is used in the minority main flow HID application.They are confined to minisystem and consumer products, such as projecting apparatus, cinematographic lighting and auto bulb [5].Main cause be the HID lamp when with high-frequency operation, can stand sympathetic response.Sympathetic response is because the power pressure in the fluorescent tube changes, and can trigger various forms of resonance, as in woodwind instrument.On the principle, by through low frequency (＜1kHz) or very high frequency (＞350kHz-700kHz) operating light is avoided [5,6].Yet modulation characteristic changes in time, when the burn-in effects of lamp becomes most important, can not guarantee the stability of lamp thus.Different with incandescent lamp, the warm-up time that the HID lamp will be rectificated is so that reach full brightness.After cut-out, before restarting them once more, they need the cooling cycle." igniting again " characteristic becomes light modulation and closes the attractive replacement scheme of lamp simply, so that avoid spending considerable time " wait " light preheating.Light modulation also has other advantages, such as energy-conservation, sense organ purpose, the flexibility that increases the multiple use area, the safer driving [2] of lamp traffic conditions, and the light pollution in the reduction exterior illumination system.Therefore, although make great efforts to develop electric ballast day by day, traditional magnetic ballast remains main selection, especially in outdoor utility.Different with electric ballast, magnetic ballast has extremely high reliability and long-life, and with respect to the robustness of instantaneous voltage surge (for example because lightning) and unfavorable operational environment (for example high humility and big variations in temperature).Especially, they provide good lamp arc stbility energy in the HID lamp.In the past, the main limitation of magnetic ballast is that they are realizing lacking flexibility aspect the brightness adjustment control.

Except that technical problem, each the single lamp that light modulation equipment is used for the illuminator be made up of a big group lamp or lamp network also is uneconomic.By replace all adjustable control equipment with adjustable device, convert non-adjustable lighting system to tunable illumination system, configuration especially is concerned about.As shown in Figure 3, wiring and electronic mounting will be very complicated, because be necessary to redesign the electric network that is used for power line and control signal.In having the system of multi-region, this situation even more complicated.Therefore, single dimmable electronic ballast is installed in will comprise high installation cost in all lampposts of roadway lighting system for example and in view of relative extreme weather situation, the weak relatively vulnerability to jamming of electric ballast concerning road lighting management company, also will be to safeguard nightmare.

Therefore, if can make magnetic ballast adjustable, the assemblage characteristic of their long-life, high reliability and economize on electricity will make this " Adjustable magnetic ballast " becomes the absorptive solution that is used for the indoor and outdoors application.In addition, it also is useful having the technology that can regulate a plurality of lamps by magnetic ballast.Fig. 4 (a) expression has the non-adjustable lamp system structure of magnetic ballast, wherein, the input of ballast is directly connected to AC power by switchgear.Use switchgear to come turn-on lamp and controlled by various devices, for example manually control, autotimer control and optical sensor.Several light-dimming methods so far that are used to have magnetic ballast had been reported.Final purpose is the control lamp current, controls lamp power thus, so that can change the brightness of lamp.Strategy mainly acts on the output or the lamp side of ballast.As described in Fig. 4 (b), they can be divided into several method.

Method I-controls to the supply voltage or the electric current of lamp

Reducing the voltage that offers ballast is the direct method of light modulation.Shown in Fig. 4 (b), when reducing supply voltage V _LThe time, source current i _L, lamp current i _Lamp, and lamp power will reduce thus.By various voltage changers,, can realize this method such as low-frequency transformer or HF switch transducer.

One of common methods who revises voltage conditions in the ballast input provides device, the voltage ratio of the power transformer in thus can the change system.When the timing of voltage rate by the turn ratio (turns-ratio), conclude if can change the turn ratio, so voltage ratio will be changed same amount [5].Adopted the whole bag of tricks, be used to realize this required variation of transformation ratio, the simplest a kind of method is included in uses many taps winding (tappedwinding) on the side of transformer, so that can change effective turn ratio.Another kind method is to use the transformer that can change the turn ratio continuously.In [7], use the double winding autotransformer to be provided for realizing two voltage levels of two level light adjusting systems.In [8], proposed to use more level light adjusting system of complex transformer.All these methods comprise the use mechanical device, such as the motor that is used to change the contactor of the turn ratio and is used for adjusting continuously the turn ratio.

Other method is to use the HF switch transducer.By the ac-dc transducer, convert the ac supply voltage to dc voltage, and, the dc voltage transitions is become ac voltage [2] by the dc-ac transducer.Therefore, whole system can be with V _L, the output of high-quality variable voltage and variable frequency is provided neatly.Yet when handling from the input of ac power supply can twice the time, whole efficient is low.For example, if the efficient of ac-dc and dc-ac transducer is 0.95, whole efficient is 0.95*0.95=0.90.

Except that using the ac-dc-ac conversion method, can use the ac-ac transducer, provide adjustable voltage such as cycloconverter with supply frequency.In [9], use power converter the ac sinusoidal voltage to be cut into potential pulse with sinusoidal envelope.In [10,11], use similar method.Yet, in this process, will generate a large amount of current harmonicss, cause the harmonic pollution problem in the electric power system.To the lamp of driving voltage sensitivity, be unsuitable such as the HID lamp.Can cause sympathetic response and the flicker effect do not expected.

Other method [12,13] is to use the next size with power supply (mains) FREQUENCY CONTROL input current of foreign current power controlling circuit.Replace this voltage swing of conversion, this method is adjusted the input current that takes out from the ac power supply.When the product of the effective power of taking out from the ac power supply and ac supply voltage and electric current is proportional, can control the whole power that is transported to lamp thus.

The control of method II-ballast-lamp impedance path

Replace the Direct Transform AC supply voltage, another light-dimming method that the explanation of Fig. 4 (c) example is connected in series this device and lamp system.The device that is connected is the variable resistor of any effective power of not dissipating in theory.When the whole impedance adjustable of lamp system is whole, V _LBecome and to adjust with the size of input current.

Described in [14], the two-stage inductor of being made up of two series reactors is used for the choke (choke) of ballast.By one switch of two inductors of energy bypass, can revise whole inductance with discrete way.

In [15], can in limited range, adjust continuously in the ballast of lamp, use saturable reactor.By adding extra winding to reactor, and direct current injected this extra winding, can saturated this core of reactor, with the impedance of the inductor in the activation change ballast.Final effect is to adjust the electric current that flows to lamp.[16] the control winding that provided by many taps autotransformer is provided the variable reactance that the variable in will have an electric current, so that can realize the various combination of equivalent serial impedance.

Replace to use active element, other method [17,18] is based on the voltage source that is connected in series with the lamp path.In [17], dc/ac transducer and lamp system are connected in series.The dc end of transducer is connected with another ac/dc transducer, and it is powered by the ac power supply.Two transducers must be handled active power and reactive power.In other words, between two transducers, there is the circulation energy.Use similar idea in [18], it is transformer coupled to implement to be based on use.Needless to say, this circulation can be introduced energy loss in this system.Except that lowering efficiency, also must handle heat problem.

Method III-control lamp terminal impedance

Shown in Fig. 4 (d), third party's method is to use the device that can shift from the electric current of ballast.Whole structure is to reduce lamp current i _LampIn [19], but at lamp two ends connection switched capacitor.If require light modulation, connect capacitor, so that will transfer in the capacitor away from lamp from that part of electric current of ballast.In this way, can control lamp current, control lamp power thus with discrete way.

Compare with said method, method I and II are suitable for adjusting a plurality of lamps, particularly existing the installation.Method III requirement improves or installs the light modulating device on each single lamp.Although all said methods can be adjusted lamp by magnetic ballast, they have restriction separately

1) require expensive and mechanical structure [7,8] in groups,

2) harmonic pollution that will not expect is introduced power system [9]-[13],

3) be not suitable for adjusting a plurality of lamps [14,15,19],

4) the total meritorious and reactive power [7-13] of control load,

5) only provide discrete light modulation [7,8], [14]-[16], [19],

6) be difficult to central authorities or control [7,8,14,15,17] automatically in the practice

7) when adjusting lamp, reduce the input power factor [14,15,16] of whole illuminator, and

8) control dissipation circulation energy [17,18].

Summary of the invention

According to the present invention, a kind of be used to be provided for velocitron or general electron illuminating system are provided, comprise the improvement power quality of the system that forms by a plurality of single lamps and the device of brightness adjustment control.This device is by the variable voltage of control illuminator, rather than the active power of control system, realizes dimming function and actual energy-conservation.In fact, only control the reactive power of whole system.The rated power of dimmer will be much smaller than the whole rated power of illuminator.The structure of preferred embodiment is shown in Fig. 5 (a).The method II that this device and Fig. 4 (c) are installed is similar, and this device and illuminator are connected in series.Replace reactance, this device is reactive power controller (RPC), and boost voltage is inserted ac supply voltage V _AcWith ballast input V _LBetween.The connection of Fig. 5 (a) expression RPC, RPC_1 is connected between ac power supply and illuminator.Boost voltage remains on 90 or 270 degree, with the current i that flows through described device _LOut-phase, and wherein, the size of boost voltage is used to change the voltage that is applied to this lamp.

In a preferred embodiment, the RPC in the device is the dc-ac transducer, is made of the full-bridge converter circuit among the half-bridge converter circuit among Fig. 6 (a) or Fig. 6 (b).The dc end of arbitrary structure is connected to the dc source.This dc source can be outside controlled dc voltage source or capacitor.The ac of bridge circuit end is by inductor L, links to each other with " B " with node " A " among Fig. 5 (a).

By the reactive power amount that control is generated or absorbed by the reactive power controller RPC_1 among Fig. 5 (a), change the size of the voltage that offers lamp, change the size of electric current thus.Yet, adjust the reactive power that is transported to lamp by using RPC_1, will reduce the input power factor of the whole system among Fig. 5 (a).Shown in Fig. 5 (b), connect the second reactive power controller RPC_2 at the ac both ends of power thus.Its function is served as power factor and is improved circuit.RPC_2 absorbs from the reactive power of the whole illuminator with the RPC_1 among Fig. 5 (a) or to it and generates reactive power, so that can improve the overall power factor of system.Ideally, be 0 from the whole reactive power of whole absorption or generation, so that make the input power factor of whole system keep single.Because two reactive power controller RPC_1 and RPC_2 mainly only control reactive power, in theory, not comprising active power in circuit operation in fact (removes, in power electronics devices, to there be some conduction and switching loss, and in inductor, exist outside copper and the core loss).Therefore, has the ability that realizes energy-efficient based on the light-dimming method that Reactive Power Control proposed.Be important to note that the RPC structure that is proposed operates in the mode that is different from traditional two-stage ac-dc connector and dc-ac converter structure [17].Although last structure is only controlled reactive power, back one structure control reality and reactive power.Energy does not circulate between two transducers.Can make the dc link. capacitor (promptly as two capacitors of voltage source (Fig. 6 a) or the value of single capacitor (Fig. 6 b)) than required littler in [17] because by the energy of two transducers controls less than in [17].Therefore, the structure that is proposed has the volt-ampere rated value littler than traditional secondary ac-dc-ac power converter system, and higher energy efficiency.

In other words, with prior art equipment, such as comparing with described in [18] in [17], advantage of the present invention is in the present invention, and RPC produces basically the voltage with 90 ° of the electric current out-phase that flows through RPC or 270 °.Thus, RPC concerning lamp ballast or AC power supplies, as if " pure " inductance or " pure " electric capacity basically basically.Because " pure " means and its reactance impedance phase ratio, the effective resistance of RPC can be ignored, and regards RPC as pure capacitor or pure inductance device with activation, and does not have significant series resistance.Those skilled in the art will recognize not dissipation energy (, outer) of capacitor and inductor such as dielectric loss in the capacitor or the hysteresis loss in the inductor except that being used for secondary effects.

On the contrary, prior art equipment described in [17] and [18], has complex impedance, comprises reactive impedance and effective true impedance.As skilled in the art will recognize, true impedance equals resistor.Thus will be on the resistance true impedance dissipation effective electron power.

When two RPC all are the dc/ac power converter, link together by dc end RPC_1 and RPC_2, in a preferred embodiment, can simplify circuit complexity and control method.Yet, concerning two RPC, may look like some problem with groundings.Two RPC can be not directly together and can require isolating transformer so as with RPC with connect or parallel branch is isolated.In this patent, will discuss half-bridge converter circuit structure along separate routes.Do not use isolating transformer, in this suggestion,, developed series connection and RPC in parallel by identical dc link (Figure 11).

Description of drawings

The operation based on the triac dimmable device of Fig. 1 (a)-(b) example explanation prior art,

Fig. 2 (a)-(c) expression is used for the general structure of the electric ballast of discharge lamp,

Fig. 3 example illustrates the architecture that dimmable electronic ballast is used for the illuminator of single lamp,

Fig. 4 (a)-(d) describes the various prior art light-dimming methods of the lamp be used to have magnetic ballast,

The various structures of Fig. 5 (a)-(b) expression light modulating device,

The schematic diagram of Fig. 6 (a)-(c) example explanation reactive power controller,

Fig. 7 (a)-(b) represents when illuminator is inductive, the phasor of system and power triangle,

Fig. 8 (a)-(b) represents when illuminator is capacitive character, the phasor of system and power triangle,

Fig. 9 example explanation is used to improve the structure of the RPC of input power factor,

Figure 10 (a)-(g) expression has may the realizing of light adjusting and controlling device of High Power Factor,

Figure 11 represents that RPC_1 and RPC_2 share the preferred embodiment of identical dc power supply,

Figure 12 (a)-(d) expression is with V _InvAnd V _{P_inv}Various combination, the equivalent electric circuit of whole system, and

Figure 13 represents to use the embodiment of AC/AC transducer.

Embodiment

The equivalent electric circuit of A.RPC

The equivalent electric circuit of the operation of example explanation expression RPC in Fig. 6 (c), wherein, by the sinusoidal voltage source V that has with ac power supply same frequency _Inv, simulation half-bridge [(Fig. 6 (a), or full-bridge [Fig. 6 (b)]) transducer.The dc end of transducer is connected to outside controlled dc voltage source or capacitor.Node " A " and " B " are connected to imaginary ac source Va by inductor L.The fundamental frequency of Va is identical with line frequency.With the frequency far above the frequency of ac power supply, the switch in two bridgt circuits of switch, [Fig. 6 (S among a ₁And S ₂] and [S among Fig. 6 (b) ₁To S ₄].By the frequency of ac power supply, the gate signal of modulation driving switch.Many pulse-width modulations (PWM) scheme that can be used for driving switch.Example comprises sine pulse width modulation (PWM), has the PWM scheme of optional harmonic wave elimination, uniform sampling PWM or the like [2].The frequency spectrum of the transducer at " C " in Fig. 6 and " D " two ends output is mainly by the inside and the cross modulation of line frequency, switching frequency and two frequencies.When inductor L be used for filtering out appear on node " A " and " B " do not expect high fdrequency component the time, by only considering line frequency, can represent V _aAnd the meritorious and quadergy stream between RPC.Therefore, the V among use Fig. 6 (c) _InvCome analog converter to be fit to.

The operating principle of B.RPC

Line frequency model shown in Fig. 6 (c) is used for illustrating the operating principle of RPC.The power P and the reactive power Q that can will flow through RPC are expressed as [3]

$P=\frac{v_a{\mathrm{<figure-callout\; id="2"\; label="v\; inv"\; filenames="S05833502320070404E000071.png,S05833502320070404E000081.png"\; state="\{\{state\}\}">v</figure-callout>}}_{\mathrm{inv}}}{2\mathrm{\&pi;fL}}\sin \mathrm{\&delta;}---\left(1\right)$

$Q=\frac{v_a(v_a-v_{\mathrm{inv}}\cos \mathrm{\&delta;})}{2\mathrm{\&pi;fL}}---\left(2\right)$

Wherein, f is a supply frequency, and δ is V _aAnd V _InvBetween phase difference.

Based on equation (1), RPC has three possible operator schemes:

If pattern I-is δ＞and 0, P＞0, inverter absorbs energy, and condenser voltage V _cIncrease.

If pattern II-is δ＜and 0, P＜0, inverter releases energy, and V _cReduce.

If pattern III-is δ=and 0, P=0 and V _cRemain unchanged.Pass through V _InvAnd V _aSize, determine Q.If V _a＞V _Inv, Q＞0.RPC serves as the reactive power absorption device.On the contrary, if V _a＜V _Inv, Q＜0.RPC serves as reactive power generator.

Ideally, RPC operates in pattern III and serves as reactive power absorption device or reactive power generator.In fact, δ absorbs the actual energy loss that can compensate among the RPC less times greater than zero because use.As shown in Fig. 6 (b), V _InvValue determine Q, V _a, and the value that is transported to the power of lamp thus.Decide by the DC source among the RPC, can use different control methods.

1. outside controlled voltage source

If the dc source is outside controlled dc voltage source, by adjusting the modulation index M and/or the dc source voltage V of bridgt circuit _DcSize, can control the amount of Q.When by the pulsation of inductor attenuate high frequency, will only consider fundametal component (being line frequency).As shown in [2],

${\mathrm{<figure-callout\; id="1"\; label="v\; inv"\; filenames="S05833502320070404E000131.png"\; state="\{\{state\}\}">v</figure-callout>}}_{\mathrm{inv}}\frac{1}{\sqrt{2}}{\mathrm{Mv}}_{\mathrm{dc}}---\left(3\right)$

Wherein, V _InvIt is the rms value.

Thus, can use M and V _DcChange V _Inv

2. direct current capacitor

If the dc end is a capacitor, V _InvControl based on changing M and/or δ.The value and the equation (3) that change M are similar,

$v_{\mathrm{inv}}=\frac{1}{\sqrt{2}}{\mathrm{Mv}}_c---\left(4\right)$

Change condenser voltage V _c, change V thus _InvOther method be by adjusting δ, making RPC_1 enter pattern I or pattern II.After this, the RPC_1 pattern III that reverses back.Final function is to adjust V with required level _c, so that in RPC, will there not be the net flow of power.Make V by use _InvWith V _aThe error amplifier of synchronous phase-locked loop and adjustment δ and/or M value can be realized this function.

C. the light modulation of lamp

By the voltage at control lamp system two ends, realize the light modulation of lamp.The phasor and the power diagram of the system of Fig. 7 (a)-7 (b) expression when lamp system is inductive.Each figure of the system of Fig. 8 (a)-(b) expression when lamp system is capacitive character.

1. inductance lamp system

Fig. 7 describes the light modulation operation with two power levels.When the input power of lamp system is P ₁The time, the supply voltage of lamp system is V _{L_1}And source current is i _{L_1}i _{L_1}Hysteresis V _{L_1}Phase difference Ф ₁When RPC and lamp system were connected in series, the electric current that flows through it also equaled i _{L_1}Shown in Fig. 5 (a), the required voltage vector V of RPC _{A_1}Perpendicular to i _{L_1}, so that RPC will not obtain any real power from the ac power supply.i _{L_1}Hysteresis V _{A_1}This means the RPC absorbing reactive power.Shown in Fig. 7 (b), reactive power is made up of two components, comprises by lamp system Q ₁The reactive power that absorbs, and by RPC Q _A-1The reactive power that absorbs.

If lamp system is adjusted to power level P ₂, supply voltage becomes V _{L_2}And source current is i _{L_2}i _{L_2}Hysteresis V _{L_2}Phase difference Ф ₂V _{L_2}Size less than V _{L_1}The vector of RPC voltage should be perpendicular to i _{L_2}With and size should be higher than V _A-1Therefore, for realizing dimming function, must increase the size of dc terminal voltage.Usually, to reduce (be Q to the reactive power that is absorbed by lamp system ₂＜Q ₁).The reactive power that is absorbed by RPC is from Q _A-1Change to Q _A-2

2. electric capacity lamp system

Fig. 8 describes the light modulation operation with two power levels.When the input power of lamp system is P ₁The time, the supply voltage of lamp system is V _{L_1}And source current is i _{L_1}i _{L_1}Leading V _{L_1}Phase difference Ф ₁Shown in Fig. 8 (a), the required voltage vector V of RPC _{A_1}Still perpendicular to i _{L_1}i _{L_1}Leading V _{A_1}This means RPC and generates reactive power.Shown in Fig. 8 (b), reactive power is made up of two components, comprises by lamp system Q ₁The reactive power that generates, and by RPC Q _A-1The reactive power that generates.

If lamp system is adjusted to power level P ₂, supply voltage becomes V _{L_2}And source current is i _{L_2}i _{L_2}Leading V _{L_2}Phase difference Ф ₂V _{L_2}Size less than V _{L_1}The vector of RPC voltage should be perpendicular to i _{L_2}With and size should be higher than V _A-1Therefore, for realizing dimming function, must increase the size of dc terminal voltage.Usually, to reduce (be Q to the reactive power that is produced by lamp system ₂＜Q ₁).The reactive power that is absorbed by RPC is from Q _A-1Change to Q _A-2

D. High Power Factor structure

As described in Fig. 7 and Fig. 8, except that the reactive power that is absorbed by lamp system or generate, RPC will absorb or generate the other reactive power from the ac power supply.This operation will cause the reduction of the input power factor of whole illuminator.When lamp power from P ₁Adjust to P ₂The time, power factor is from cos θ ₁Be reduced to cos θ ₂Can improve power factor although connect capacitor at ac power supply input two ends, required capacitor value is relevant with lamp power.By connect another controller RPC_2 at the ac both ends of power, shown in Fig. 5 (b), on any lamp power, make power factor keep single.

To the inductance lamp system, need be by the required electric inductance power Q of RPC_2 generation _P[Fig. 7 (b)] equal in any power level the reactive power that absorbs by lamp system and RPC_1 and.If the input power of lamp system is P ₁,

Q _{P_1}＝Q _{a_1}+Q ₁ (5)

If the input power of lamp system is P ₂,

Q _{P_2}＝Q _{a_2}+Q ₂ (6)

Fig. 7 (b) example explanation Q _P-1And Q _P-2Vector.Therefore, Q _PRelevant with load.

To the capacitive character lamp system, need be by the required electric inductance power Q of RPC_2 absorption _P[Fig. 8 (b)] equal in any power level the reactive power that generates by lamp system and RPC_1 and.Equation (5) and (6) are still effective.Fig. 8 (b) example explanation Q _P-1And Q _P-2Vector.Similarly, Q _PRelevant with load.

In inductive and capacitive character lamp system, Q _PDecide by equation (2).As shown in Figure 9, bridge transducer voltage V _{P_inv}Determine Q _PValue.Power and idle stream between equation (1) and (2) expression ac power supply and RPC_2.That is,

$P_P=\frac{v_{\mathrm{ac}}{v}_{P\_\mathrm{<figure-callout\; id="2"\; label="inv"\; filenames="S05833502320070404E000071.png,S05833502320070404E000081.png"\; state="\{\{state\}\}">inv</figure-callout>}}}{{2\mathrm{\&pi;fL}}_P}\sin {\mathrm{\&delta;}}_P---\left(7\right)$

$Q_P=\frac{v_{\mathrm{ac}}(v_{\mathrm{ac}}-v_{P\_\mathrm{inv}}\cos {\mathrm{\&delta;}}_P)}{{2\mathrm{\&pi;fL}}_P}---\left(8\right)$

Wherein, δ _PBe V _AcAnd V _{P_inv}Between phase difference.

Similarly, RPC_2 has three possible operator schemes:

If pattern I-is δ _P＞0, P _P＞0, inverter absorbs energy, and condenser voltage V _{P_C}Increase.

If pattern II-is δ _P＜0, P _P＜0, inverter releases energy, and V _{P_C}Reduce.

If pattern III-is δ _P=0, P _P=0, and V _{P_C}Remain unchanged.

By V _{P_inv}And V _AcSize, determine Q _PIf V _Ac＞V _{P_inv}, Q _P＞0.RPC_2 serves as the reactive power absorption device.On the contrary, if V _Ac＜V _{P_inv}, Q _P＜0.RPC_2 serves as the reactive power maker.

Q _PControl based on the phase shift between monitoring ac supply voltage and whole input current.Similar with RPC_1, voltage V _{P_inv}Determine Q _P, and by adjusting RPC_2 and/or δ _PModulation rate control.For example, if lamp system is inductive, RPC_1 will be operating as the reactive power absorption device, and RPC_2 will be operating as reactive power generator.If input current hysteresis supply voltage, control circuit will increase the dc link voltage (i.e. this capacitor or as the voltage of the capacitor in dc voltage source) of RPC_2, so that RPC_2 will generate more reactive powers, will reduce the phase difference between supply voltage and input current thus.If input current leading current voltage, control circuit will reduce the dc link voltage of RPC_2, so that RPC_2 will generate still less reactive power, will reduce the phase difference between supply voltage and input current thus.As shown in Figure 7 and Figure 8, be respectively applied for power level P ₁And P ₂Whole input current i _L-1' and i _L-2' will with ac power supply homophase, power factor is single thus.

E.RPC_1 and the shared identical dc of RPC_2 source

Figure 10 represents may realize by the light adjusting and controlling device of High Power Factor.Figure 10 (a) expression can be used for two semi-bridge convertors a kind of possibility of RPC_1 and RPC_2.In the method, require four dc capacitors and four semiconductor switchs.Figure 10 (b) expression can be used for two full-bridge converters another possibility method of RPC_1 and RPC_2.In this case, require two capacitors and eight switches.Other possibilities are the combinations that half bridging and full-bridge converters are used for RPC_1 and RPC_2.Figure 10 (c) expression RPC_1 uses semi-bridge convertor and RPC_2 to use the possibility of full-bridge converters.Figure 10 (d) expression RPC_1 uses full-bridge converters and RPC_2 to use the possibility of semi-bridge convertor.

If make up the dc link source of RPC_1 and RPC_2, can reduce the quantity of capacitor.Yet, if two controllers shown in the direct connection layout 8 can form the short circuit path between live wire and zero line.For avoiding short circuit problem, can use transformer isolation RPC_1 and RPC_2.The various combination that Figure 10 (e)-(g) expression uses transformer to isolate RPC_1 and/or RPC_2.This will introduce the other power loss on the transformer.

Figure 11 represents the RPC_1 in shared identical dc source and RPC_2 and the embodiment that does not need transformer.Such as among Figure 11 encirclement, RPC_1 is by S ₁, S ₂Form with two capacitors, and RPC_2 is by S ₃, S ₄Form with two capacitors.By RPC_1 in the research light modulating device and the integrated operation of RPC_2, its operation can be described.Figure 12 (a)-(d) expression is with V _InvAnd V _{P_inv}The equivalent electric circuit of whole system of various combination.Because V _InvAnd V _{P_inv}Can be plus or minus, draw four kinds of possible combinations.S ₁, S ₂, L and two capacitors form RPC_1, and S ₃, S ₄, L _PForm RPC_2 with two capacitors.When connecting S ₁And S ₃The time, form the circuit shown in Figure 12 (a).When connecting S ₂And S ₃The time, form the circuit shown in Figure 12 (b).When connecting S ₁And S ₄The time, form the circuit shown in Figure 12 (c).At last, when connecting S ₂And S ₄The time, form the circuit shown in Figure 12 (d).

On the other hand, as mentioned above, by controlling by S ₁And S ₂The modulation index of the transducer that forms, and V _InvAnd V _aBetween phase shift, can change V _LOn the other hand, by control V _AcAnd V _{P_inv}Between phase shift and the modulation index of RPC_2, can improve power factor.Two transducers are not handled any active power in the whole system.

Adjust V _AcAnd V _{P_inv}Between phase shift and by switch S ₃And S ₄The modulation index of the inverter that forms can be controlled the reactive power amount that is generated or absorbed by RPC_2.When the dc source is common to RPC_1 and RPC_2, by changing by switch S ₁And S ₂The modulation index of the inverter that forms can be carried out the light modulation of lamp.

In a further embodiment, can use AC voltage source (replacing the dc voltage source) and AC/AC electric pressure converter (replacing the DC/AC electric pressure converter) to produce the auxiliary AC voltage at RPC_1 and RPC_2 two ends, as shown in figure 13.

The frequency of AC power supplies changes usually.For example, specified 50HzAC power supply can change between 49Hz and 51Hz.Therefore, in many examples, expectation comprises frequency locking device, such as FLL or phase-locked loop (PLL).

Ideally, flow through the voltage and current of RPC_1 and/or RPC_2 will be just in time 90 ° of out-phase so that RPC_1 and/or RPC_2 serve as ideal inductor or ideal capacitor.In fact, some losses are still arranged in RPC_1 and/or RPC_2.Some losses will be from switching loss, for example from half-bridge or full-bridge circuit.Simultaneously, to magnetic ballast and AC power supplies, control circuit will require electrical power to work, and this electronic power will occur, as little real resistance.Thus, although preferably for real impedance, voltage and current is 90 ° of out-phase just in time, and when voltage and current 1 ° of out-phase during at 90 °, when 5 ° or 10 °, the present invention can implement.

Can use above-mentioned full-bridge to connect or the half bridging technology, and the power converter of other types generate boost voltage.Be desirably among most of embodiment, power semiconductor device will for example be supposed half-bridge or full-bridge as switch.The example of suitable power semiconductor device is igbt (IGBT), although it should be appreciated by those skilled in the art that, can use the equipment of other types.

The present invention can be applied to electronic lamp ballast and magnetic lamp ballast.Those skilled in the art will recognize some electric ballasts and comprise the power adjustment, for example allow by the AC power supplies operating light in the scope of 110V to 240V.The present invention is when in conjunction with comprising that power adjusts electric ballast and use, and the present invention may be not too effective because, if RPC increases the effective impedance of AC power supplies, so electric ballast will reduce them equiva lent impedance to the impedance increase of to a certain degree offsetting RPC.

The present invention can with gaseous discharge lamp, such as high-pressure sodium lamp, low-pressure sodium lamp, fluorescent lamp and high-intensity discharge lamp, use together such as metal halide lamp.

The invention particularly relates to simple general-purpose purpose and non-intruding light adjusting system, can be updated to existing lamp and, the normal running of lamp is not had on the meaning of influence for non-invasive when not using this light adjusting system.As shown in Figure 9, if when by-pass switch can be connected RPC_1 two ends and RPC_1 operation, be to disconnect.If RPC_1 does not use, by-pass switch is with closure, and nothing is interruptedly by the ac power supply illuminator.

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Claims (35)

1. a reactive power controller is used for light modulation AC power supplies illuminator, and this reactive power controller comprises:

First and second terminals are used to be connected to the AC power supplies illuminator;

Voltage forms device, is used for the supply frequency between first and second terminals, forms AC voltage;

Signal receiving device is used to receive the light modulation level controling signal; And

Control device is used for based on the light modulation level controling signal, and control forms the voltage that device forms by voltage.

2. reactive power controller as claimed in claim 1, wherein, control device is used for making voltage to form device and forms and the AC voltage that flows to the electric current out-phase of second terminal from the first terminal.

3. reactive power controller as claimed in claim 2, wherein, control device is used for making voltage to form device and forms and the electric current out-phase that flows to second terminal from the first terminal 90 ° or 270 ° AC voltage basically basically.

4. reactive power controller as claimed in claim 2, wherein, control device be used for making voltage form device be formed on 80 ° to the 100 ° scopes of electric current out-phase that flow to second terminal from the first terminal or AC voltage in 260 ° to 280 ° scopes.

5. reactive power controller as claimed in claim 4, wherein, control device be used for making voltage form device be formed on 85 ° to the 95 ° scopes of electric current out-phase that flow to second terminal from the first terminal or AC voltage in 265 ° to 275 ° scopes.

6. reactive power controller as claimed in claim 4, wherein, control device be used for making voltage form device be formed on 89 ° to the 91 ° scopes of electric current out-phase that flow to second terminal from the first terminal or AC voltage in 269 ° to 271 ° scopes.

7. as claim 2 or 3 described reactive power controllers, wherein, control device comprises frequency locking device.

8. as any one described reactive power controller of claim 1 to 6, wherein, control device comprises phase-locked loop (PLL).

9. as any one described reactive power controller of claim 1 to 6, comprise the device that is used for receiving from the dc voltage source dc voltage, wherein, voltage forms device and is used for converting dc voltage to AC voltage.

10. as any one described reactive power controller of claim 1 to 6, comprise the dc voltage source, wherein, voltage forms device and is used for converting the dc voltage from the dc voltage source to AC voltage.

11. reactive power controller as claimed in claim 10, wherein, control device is used for based on the light modulation level controling signal, and the voltage in control dc voltage source is controlled thus by voltage and formed the voltage that device forms.

12. reactive power controller as claimed in claim 10, wherein, the dc voltage source comprises capacitor device.

13. reactive power controller as claimed in claim 10, wherein, the dc voltage source comprises two capacitor connected in series devices.

14. reactive power controller as claimed in claim 2, comprise the dc voltage source, voltage forms device and is used for converting the dc voltage from the dc voltage source to AC voltage, the dc voltage source comprises capacitor device, wherein, control device is used for based on the light modulation level controling signal, with respect to the electric current that flows to second terminal from the first terminal, the phase place of control AC voltage, thus the storage or the releasing capacitor device in energy, change the voltage of capacitor device thus, and control thus by voltage and form the voltage that device forms.

15. reactive power controller as claimed in claim 2, comprise the dc voltage source, voltage forms device and is used for converting the dc voltage from the dc voltage source to AC voltage, the dc voltage source comprises two capacitor connected in series devices, wherein, control device is used for based on the light modulation level controling signal, with respect to the electric current that flows to second terminal from the first terminal, the phase place of control AC voltage, thus the storage or the releasing capacitor device in energy, change the voltage of capacitor device thus, and control thus by voltage and form the voltage that device forms.

16. reactive power controller as claimed in claim 9, wherein, voltage forms device and comprises switching device, to have positive polarity then during first and second terminals of reversed polarity by dc voltage alternately is connected to, converts dc voltage to AC voltage.

17. reactive power controller as claimed in claim 16, wherein, switching device comprises semi-bridge convertor.

18. reactive power controller as claimed in claim 16, wherein, switching device comprises full-bridge converters.

19. reactive power controller as claimed in claim 16, wherein, switching device comprises power semiconductor switch equipment.

20. reactive power controller as claimed in claim 19, wherein, switching device comprises insulated gate bipolar transistor (IGBT).

21. reactive power controller as claimed in claim 16, wherein, voltage forms device and comprises inductor arrangement, is used to the high-frequency current pulsation that decays and formed by switching device.

22. reactive power controller as claimed in claim 16, wherein, control device is used for based on the light modulation level controling signal, and the modulation index of control switch device is controlled thus by voltage and formed the voltage that device forms.

23. as any one described reactive power controller of claim 1 to 6, wherein, signal receiving device is used for receiving dc voltage, as the light modulation level controling signal.

24. a connection in series-parallel reactive power controller is used for light modulation AC power supplies illuminator, this connection in series-parallel reactive power controller comprises:

As any one described reactive power controller according to claim 1 to 23 of first reactive power controller, the AC power supplies illuminator that is used to be connected in series is so that control the power that offers the AC power supplies illuminator idlely;

Any one described reactive power controller as second reactive power controller according to claim 1 to 23, be used to be connected in parallel first reactive power controller and AC power supplies illuminator two ends, so that improve the power factor of first reactive power controller and AC power supplies illuminator

Wherein, be electrically connected first and second reactive power controllers so that shared public dc voltage source.

25. connection in series-parallel reactive power controller as claimed in claim 24 wherein, directly connects first and second reactive power controllers so that shared public dc voltage source.

26. connection in series-parallel reactive power controller as claimed in claim 24 comprises device for transformer, connects first and second reactive power controllers so that shared public dc voltage source.

27. an adjustable AC power supplies illuminator comprises:

Be used to receive the device of input AC power supplies;

One or more lamp ballasts, and

Any one described reactive power controller as first reactive power controller according to claim 1 to 23, wherein, its first and second terminal through between input power supply and one or more magnetic lamp ballast, first reactive power controller is connected in series.

28. adjustable AC power supplies illuminator as claimed in claim 27, wherein, one or more lamp ballasts comprise one or more magnetic lamp ballasts.

29. adjustable AC power supplies illuminator as claimed in claim 27, wherein, one or more lamp ballasts comprise one or more electronic lamp ballasts.

30. any one described adjustable AC power supplies illuminator as claim 27 to 29, comprise any one described reactive power controller according to claim 1 to 23 as second reactive power controller, wherein, through first and second terminals at the input both ends of power, second reactive power controller is connected in parallel.

31. adjustable AC power supplies illuminator as claimed in claim 30 wherein, is electrically connected first reactive power controller and second reactive power controller, so that shared public dc voltage source.

32., wherein, be used to receive the device of importing AC power supplies and comprise switchgear as any one described adjustable AC power supplies illuminator of claim 27 to 29.

33. any one the described adjustable AC power supplies illuminator as claim 27 to 29 comprises the one or more lamps that are connected respectively to one or more lamp ballasts.

34. adjustable AC power supplies illuminator as claimed in claim 33, wherein, one or more lamps comprise gaseous discharge lamp.

35., be included in the by-pass switch device at the first reactive power controller two ends as any one described adjustable AC power supplies illuminator of claim 27 to 29.

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