A power saving device for a light-bulb

Abstract

Modern light-bulbs (500) save power, but as an unwanted side effect, may generate common mode noise and / or differential mode noise that may increase operational cost. This invention discloses a power saving device (701) for a light-bulb (500) that may suppress mentioned noise, thereby saving electrical power. The system further allows easy installation, without the need to call out a technician. A system, as disclosed, connected external from a light-bulb (500), may allow reuse, once the useful life of the light-bulb (500) expires, thereby reducing waist. Advantageous, the system may also serve as a focal point in a room, to advertise or promote (745), a third party, company, service, product, logo, slogan, e-mail address or similar.

Description

[0001] A Power Saving Device for a light-bulb

[0002] Technical Field

[0003] This invention discloses a power saving device for a light-bulb, arrange for connection between a light-bulb socket and a light-bulb. Metered electrical power usage, may be reduced by suppressing noise generated by said light-bulb. In the context of this disclosure, noise, refers to common mode (CM) noise and / or differential mode (DM) noise in an electrical system. The disclosed invention may allow easy installation.

[0004] Background Art

[0005] It will be noted that, in the context of this disclosure, an electronic light-bulb(s), refers to an LED light-bulb(s) and / or a compact fluorescent light-bulb(s) or similar.

[0006] It is estimated that approximately 20% of electrical power generated in the world, is consumed by lighting systems. Modern electronic lightbulbs, is an increasingly popular lighting solution, due to reduced power requirements, and has a large impact on every-day life.

[0007] An LED light-bulb requires a LED driver. Mentioned LED driver may perform various functions, for example: ac-to-dc power conversion, dc-side ripple reduction, providing the light emitting diode(s) with the correct voltage and / or current level, the output current provided to the LEDs, may be controlled dependent on the temperature of the LEDs. Additionally an LED driver may perform functions like active power factor correction (APFC), etc. As yet another feature, an LED driver circuit may typically be arranged to provide either a constant voltage output or constant current output to the light emitting diode(s).

[0008] Alternating current (ac) is still the dominant power interface to electronic light-bulbs. As mentioned, an LED driver, inter alia, needs to convertac power to de power. During mentioned conversion process, signal distortion or harmonics may be generated at the ac side. Harmonics and their negative effects on electrical systems is a well known problem and therefore do not require further explanation, suffice to mention that harmonics increases apparent power, losses and increases required current, without converting the increase in current to useful work.

[0009] An LED is a fast acting device, and therefore requires a relatively smooth de signal to reduce or avoid LED light flicker or a stroboscopic effect. Rapid LED light flicker may be noticeably perceived or unnoticeably perceived. Negative impacts of LED light flicker on the well-being of humans may include: headaches, reduced concentration, discomfort, dislike of the lighting system, etc. Usually a dc-filtering capacitor is used. A large value dc-filtering capacitor may help to reduce flicker but may increase harmonics, and vice versa; and therefore introduce design constraints.

[0010] In order to protect the integrity of the mains grid, there are standards for harmonics and standards for power factor (PF) for lighting equipment, in most countries. Open source published research on LED lightbulbs indicate that most systems do not comply with current international harmonic standards. It is a challenge for a LED lighting equipment manufacturer to manufacture an efficient LED driving circuit, especially for low power lightbulbs, of a relative small size and relative low cost. Mentioned size and cost restrictions may be critical parameters, in the highly competitive technical sphere of low power, low cost light-bulbs.

[0011] A dimmable LED lighting system may be desirable for various reasons. Dependent on the electric / electronic configuration used to achieve the light dimming functionality, harmonic content may be increased.Harmonics display an unexpected characteristic in that, in general, harmonics increase with a decrease in consumed power. Due to their low power demand, electronic light-bulbs may cause high levels of harmonic distortion.

[0012] Supraharmonics (SH) is a relative new power quality (PQ) phenomenon that emerged to the general attention of researchers, approximately during 2013. SH is currently unregulated and causes multiple new problems, power losses and inefficiencies in electrical systems. SH is generated due to high frequency switching operations of electronic semiconductors. An impulse in the time-domain or dirac delta function, (r), may cause a plurality of frequencies in the frequency-domain. High frequency, spike-like SH, may cause an impulse-like function or impulse-train-like function, thereby evoking an impulse response from a system, superimposed on other signal components.

[0013] Reported SH emissions originate from several devices including: LED and florescent lamps. Multiple circuits used in electronic light-bulbs may be a source of SH emissions; including: active harmonic filters (AHF), active power factor correction circuits (APFC), dc-dc converters, etc.

[0014] Some of the reported problems related to SH are: premature aging of insulation materials, premature aging of capacitors, light output flicker of LED lamps and / or light output intensity variations, electric meters reporting inaccurate measurements, beat-frequencies, narrowband noise or wideband noise, intermodulation effects, conductor crosstalk, degrading of surge protection devices. An electronic light-bulb may generate SH, that may interfere with the correct operation of an earth-leakage protection device, causing hazards to both people and property.

[0015] Recently (during approximately 2025), it was also discovered that SH may significantly increase peak and / or RMS current. According to research, SH may double or even triple peak current levels.Research further suggest that in general, SH do not diminish with an increase in power usage; therefore SH do not display the same properties as harmonics.

[0016] Consumers may falsely be under the impression that SH is an academic problem, with limited or no direct impact on them. To illustrate; an electronic light-bulb, may be used in combination with another appliance using high instantaneous current, (for example a kettle, stove, air-conditioner or similar). SH, generated by mentioned electronic light-bulb, may be superimposed on the high current consumed by mentioned appliance, thereby significantly increasing, the instantaneous metered power usage, of not only the current consumed by the electronic light-bulb, but the total current supplied to the premises.

[0017] In accordance with EMC standards, electronic light-bulbs should be able to work correctly in their own electromagnetic environment, without disturbing other appliances used in the same environment. It is anticipated that the use of air-conditioning systems may increase with global heating on the rise, making electronic light-bulb compliance with EMC standards, vital.

[0018] PROPOSED NEW LAW for harmonics and supraharmonics: Supraharmonics may superimpose on the fundamental frequency component, while in general, harmonics may superpose on the fundamental frequency component, thereby causing distortion of the fundamental frequency. In the presence of both supraharmonics and harmonics, supraharmonics may superimpose on superposed harmonics.

[0019] The reason for this is, partly, due to the fact that the higher frequencies of SH (2 kHz - 150 kHz) travels along the outside surface of a conductor, due to the skin-effect. Since low frequency fundamental current andhigh frequency SH currents travels along different path ways in a conductor, this avoids signal cancellation, but causes SH to be superimposed on the fundamental frequency signal component. Harmonics have lower frequency components (below approximately 2 kHz), causing less skin-effect, thereby resulting in more interaction with the fundamental frequency signal component.

[0020] Multiple harmonic suppression systems are known, that can be installed. Mentioned systems usually require serial / line installation between an ac source and one or more electronic light-bulbs. This may require the services of a technician, at financial cost, to climb into the ceiling of a home, office or shop, or to operate at an electrical distribution box, in order to install mentioned harmonic suppression system. If a centralised harmonic suppression system should become defective, a home, office or shop may be left without any power for electrical lighting, until the services of a technician can be acquired again.

[0021] Since there currently exists NO SH STANDARDS; but standards, for both harmonics and minimum power factor compliance for lighting systems, this creates a void, allowing a technical sidestep of the law. It will be noted that, as the proliferation of harmonic generating devices increases, stricter enforcement of harmonic standards may result. Additional harmonic and / or SH suppression methods may expectantly be encouraged.

[0022] It will be noted that, direct SH emissions, can relatively easy be suppressed by connecting a capacitor in shunt (or parallel) across ac mains wires. However, as an unintended consequence, if no line reactor is used, mentioned capacitor may attract secondary SH emissions from a neighbouring premises. Therefore, a neighbour may influence the power consumption of a property owner, without the property owner’s knowledge or consent. This is an unfair practise and may further increase operational cost of an electronic lightbulb.A valley-fill circuit is known and used in some LED light bulbs, as a passive filter for suppressing harmonics. However, a valley-fill circuit may have limited or no effect on SH, generated by a high frequency switching circuit.

[0023] As further background information, in general for an ac-dc converter; an ac line reactor or a de line choke may be used to suppress harmonics. Both have certain advantages and disadvantages. In general, an ac reactor and a de choke may cause approximately the same overall reduction in the total harmonic distortion (THD), but a de line choke may cause an increase in the weighted partial harmonic current of approximately 13%, from approximately the 14thto the 40thharmonic. It can reasonably be expected that this trend may continue in the SH range. Therefore, an ac line reactor may be preferred for suppressing high frequency noise. Said ac line reactor may be arranged as part of the disclosed system.

[0024] The pulsating current effect of diodes and the switching circuit of a dc-dc converter may produce common mode noise. Common mode noise may aggravate ringing. An electronic light-bulb may use a diode rectifier and / or dc-dc converter and / or an active power factor correction circuit. All of mentioned circuits may be sources of common mode noise. Common mode noise may cause conducted and / or radiated emissions. SH may manifest as common mode noise and / or differential mode noise.

[0025] An incandescent light-bulb may be a source of Johnson-Nyquest noise (or thermal noise). Thermal noise is proportional to the absolute temperature. At room temperature a 3k ohm resistor may cause approximately one microvolt RMS noise over a 20 kHz frequency band. The filament of an incandescent light-bulb may operate at a high temperature, and may possibly be a source of radiated common mode noise.Prior art blindly accepted that an incandescent light-bulb may resemble a resistive load causing a linear response with no harmonics. The patent applicant performed simple experiments using a line resistor and oscilloscope and was surprised to see the level of current distortion caused by an incandescent light-bulb. A sixty (60) watt incandescent light-bulb may cause an inrush surge current of approximately seven (7) amp, and may also benefit from a line reactor. However, the noise generated by an incandescent light-bulb may be smaller compared to an electronic light-bulb; therefore this invention may preferably be used to suppress noise generated by an electronic light-bulb.

[0026] Un-grounded appliances (like electronic light-bulbs), may aggravate radiated common mode noise emissions. Furthermore, the ac mains power wires of an appliance may act like a quarter wave antenna for EMI emissions. According to research literature, common mode noise may approximately be ten (10) to one hundred (100) times more detrimental to sensitive electronics circuits, compared to differential mode noise.

[0027] Common mode noise may have limited or no direct effect on the operation of an electronic light-bulb. However, a smart meter (with sensitive electronics) may use a floating ground, resulting in inaccurate metered power, due to common mode noise interference. Accuracy testing of smart meters takes place, under controlled laboratory conditions. Several international research articles have already pointed out difficulties with accurately metering power, under real-world conditions, in the presence of noise disturbances.

[0028] For suppressing common mode noise and SH, passive filtering components may be preferred, since, as already mentioned an active harmonic filter may generate SH. In general, passive component(s) may be bulky or have a relative large form-factor, causing difficulties in fitting mentioned passive component(s) into the limited space available inside an electronic light-bulb. It will further be realised that passive filtering component(s) may be reused saving onmanufacturing cost; therefore making no economic sense to install mentioned passive component(s) inside an electronic light-bulb, that may be discarded at the end of its useful life.

[0029] It is anticipated that SH standards may be developed in the future and that mentioned standards, may possibly be more restrictive than current harmonic standards. A power saving device for a light-bulb, as disclosed, connected external from an electronic light-bulb, may help with EMC compliance, while still allowing an electronic light-bulb manufacturer to remain cost competitive with rivals.

[0030] In order to save cost, electronic light-bulb manufacturers may employ noise filters, designed to reach minimal compliance levels, or inadequate, or no noise filters; with specific emphasis on common mode noise suppression techniques. In many countries, products are imported without being subjected to scrutiny for compliance with standards. Another problem is counterfeit products, of a low standard, imitating legitimate products.

[0031] As background, radio frequency interference (RFI), may be generated by an electronic light-bulb and may cause radiated common mode noise. RFI may be sub-divided into near field and far field effects. Prior art noise screening techniques may not be sufficient to protect ac power wires from near field RFI, since ac power wires effectively need to pass through mentioned noise screen. Electronic light-bulb manufacturers largely overlooked the need to suppress conducted and / or radiated common mode noise that may be generated by a light-bulb, from coupling to ac mains power wires. Therefore, there is an urgent need for this patent in the market.

[0032] Summary of Invention

[0033] Statement: no artificial intelligence (Al) methods were used to create this patent.It will clearly be noted that, compliance with minimum harmonic standards remains the principal responsibility of a light-bulb manufacturer. This invention may help to provide additional common mode noise or common mode noise and differential mode noise, suppression where: adequate, inadequate or no measures are employed by a light-bulb. Additional harmonic suppression, over and above minimum harmonic requirements, may further help to save power.

[0034] According to one broad aspect of this invention; it is an object of this invention to disclose a power saving device for a light-bulb, that can easily be installed without the need of the services of an electrician, technician or similar to install the system.

[0035] It is an object of this invention to suppress near field RFI , generated by a light-bulb, from coupling to the ac mains power wires. It will be noted that prior art centralised noise suppression systems were installed relatively far away from a light-bulb and therefore could not suppress near field RFI noise.

[0036] It is an object of this invention to reduce electrical signal interaction, between a light-bulb and another electric / electronic system, used in the same electromagnetic environment and in relative close proximity to each other.

[0037] It is an object of this invention to increase the electrical safety of a system, by suppressing noise that may be generated by a light-bulb, thereby helping to improve accurate operation of an earth-leakage protection system.

[0038] It is an object of this invention to disclose a power saving device for a light-bulb that may help to improve the true power factor (TPF), of a system. The true power factor (TPF) may depend on the total harmonic distortion (THD), and may be defined as:<>

[0039]

[0040] In general, LED lighting, without a power factor correction circuit, may cause a leading current-voltage phase shift or capacitive reactance, Xc ; therefore an noise suppression filter, with inductive properties, may be preferred to absorb the reactive power.

[0041] It will clearly be noted that pending PCT application PCT / ZA2025 / 050065, belonging to the same patent applicant, discloses an inductive component, (with specialised characteristics), that may, inter alia, operable be arranged interposed between a light-bulb socket and a light-bulb. The current subject matter discloses a power saving device for a light-bulb, arranged for operation between a light-bulb socket and a light-bulb. Mentioned power saving is achieved by suppressing common mode noise or common mode noise and differential mode noise, Therefore, PCT / ZA2025 / 050065, do not infringe on the current subject matter and vice versa.

[0042] Brief Description of Drawings

[0043] Fig. 1 shows a schematic diagram of one embodiment of a power saving device for a light-bulb, in accordance with the current subject matter and an exemplary use of this invention.

[0044] Fig. 2 shows a schematic diagram of another embodiment of a power saving device for a light-bulb, further arranged as an advertising platform, in accordance with the current subject matter, and an exemplary use of this invention.

[0045] Fig. 3 shows a simplified schematic diagram of another embodiment of a power saving device for a light-bulb, arranged to suppress common mode noise, generated by near field radio frequency interference, inaccordance with the current subject matter, and an exemplary use of this invention.

[0046] Fig. 4 shows a simplified schematic diagram of another embodiment of a power saving device for a light-bulb, in accordance with the current subject matter.

[0047] Fig. 5 shows a simplified schematic diagram of another embodiment of a power saving device for a light-bulb, in accordance with the current subject matter.

[0048] Fig. 6 shows a schematic diagram of a test setup used to do a test measurement, and is included for background information only.

[0049] Fig. 7 shows a schematic diagram of approximately an oscilloscope picture from an analogue oscilloscope, using the test setup shown in Fig. 6, and is included for background information only.

[0050] Description of Embodiments

[0051] The invention will now be further described, by way of example, with reference to the following diagrammatic drawings.

[0052] Fig. 1 shows a schematic diagram of one embodiment of a power saving device for a light-bulb (700), in accordance with the current subject matter, and an exemplary application; (see Fig. 1).

[0053] A power saving device for a light-bulb (700), arranged for suppressing common mode noise or common mode noise and differential mode noise, in accordance with the current subject matter, may comprise:

[0054] A light-bulb fitting (710) arranged for insertion into a light-bulb socket (100), wherein said light-bulb fitting (710) may be arranged for mechanical and electrical coupling to said light-bulb socket (100). Said light-bulb fitting (710), may be arranged the same or similar to a prior art base structure of a light-bulb. It will be appreciated that a wide variety of prior art base structure configurations,for light-bulbs are known. Although a bayonet-type base structure arrangement is shown for said light-bulb fitting (710), any suitable coupling configuration may be used.

[0055] Said light-bulb socket (100) may be electrically connected to ac mains power wires (103; 104).

[0056] A light-bulb holder-socket (750), arranged for receiving a light-bulb (500), wherein said light-bulb holder-socket (750) may be arranged for mechanical and electrical coupling to said light-bulb (500). It will be appreciated that, although a bayonet-type coupling arrangement is shown for said light-bulb holder-socket (750) any suitable coupling configuration may be used.

[0057] In another embodiment (not shown), said light-bulb holder-socket (750) may be arranged to use a proprietary coupling configuration, to allow only a light-bulb, manufactured by a certain light-bulb manufacturer, to couple / mate with said light-bulb holder-socket (750).

[0058] Said power saving device for a light-bulb (700), may be enclosed in a suitable enclosure (740). It will be understood that said suitable enclosure (740) may take any desirable shape.

[0059] And, a means, for suppressing common mode noise, or common mode noise and differential mode noise, wherein said means may further be arranged to transport electrical power between said light-bulb fitting (710) and said light-bulb holder-socket (750). Said means (720), may be enclosed by said suitable enclosure (740) and therefore the detail of said means (720) is not shown in Fig. 1.

[0060] Without limitation, said means (720) may for example comprise: a common mode choke (not shown); or at least one section of a twisted wire pair(not shown); or a common mode choke electrically connected in series with at least one section of a twisted wire pair.

[0061] Or, said means may for example comprise: at least one section of a twisted wire pair (not shown) and at least one reactor (not shown), wherein said at least one reactor may be electrically connected in series with one wire of said at least one section of a twisted wire pair.

[0062] In another embodiment, (not shown), said suitable enclosure (740) may be arranged to represent a desirable object, for example: the base of a candle with dripping candle wax, or a rocket, or a flying saucer, or the Earth, or Saturn with it’s rings, or an animated or mythological character, etc.

[0063] Fig. 2 shows a schematic diagram of another embodiment of a power saving device for a light-bulb (701) and an exemplary application, in accordance with the current subject matter, wherein said power saving device for a light-bulb (701) may further be arranged as an advertising platform (see Fig. 2).

[0064] Advertising companies compete against rivals in a competitive environment and are constantly searching for new opportunities to draw attention to a product. A light-bulb may be a central focal point in a room, or may occupy a prime position in a room. It can reasonably be expected that, a light-bulb manufacturer would not agree to promote a third party, via their product. Therefore, a power saving device for a light-bulb, as disclosed, may further be arranged to advertise a company and / or a product, and / or a service and / or a logo of a company and / or a slogan of a company and / or contact detail of a company; or in general, to promote a third party.

[0065] It will be understood that in Fig. 2, the words “COMPANY J J J” (745), is shown by way of example only, and that any appealing word(s), phrase(s), picture(s) or similar, to endorse or promote a third party, may be used.Fig. 3 shows a simplified schematic diagram of another embodiment of a power saving device for a light-bulb (702), in accordance with the current subject matter, and an exemplary application; (see Fig. 3).

[0066] A power saving device for a light-bulb (702), arranged for suppressing near field radio frequency interference (RFI), (or radiated common mode noise), in accordance with the current subject matter, may comprise:

[0067] A light-bulb fitting (710) arranged for insertion into a light-bulb socket (100), wherein said light-bulb fitting (710) may be arranged for mechanical (714) and electrical (711, 712) coupling to said light-bulb socket (100). Said lightbulb fitting (710), may be arranged the same or similar to a prior art base structure of a light-bulb. It will be appreciated that a wide variety of prior art base structure configurations for light-bulbs are known. Although a bayonet-type base structure (714) arrangement is shown for said light-bulb fitting (710), any suitable coupling configuration may be used.

[0068] Said light-bulb socket (100) may be electrically connected to ac mains power wires (103, 104).

[0069] A light-bulb holder-socket (750), arranged for receiving a light-bulb (500), wherein said light-bulb holder-socket (750) may be arranged for mechanical (754) and electrical (751, 752) coupling to said light-bulb (500). It will be appreciated that, although a bayonet-type coupling (754) arrangement is shown for said light-bulb holder-socket (750) any suitable coupling configuration may be used.

[0070] In another embodiment (not shown), said light-bulb holder-socket (750) may be arranged to use a proprietary coupling configuration, to allow only alight-bulb, manufactured by a certain light-bulb manufacturer, to couple / mate with said light-bulb holder-socket (750).

[0071] And, at least one section of a twisted wire pair (728), wherein said at least one section of a twisted wire pair (728) may be arranged to transport electrical power between said light-bulb fitting (710) and said light-bulb holdersocket (750). Said at least one section of a twisted wire pair (728), may be arranged to have an input-port (728a; 728b) and an output-port (728c; 728d). For clarity (728-J) shows an enlarged view of one embodiment of said at least one section of a twisted wire pair (728).

[0072] Preferably, said at least one section of a twisted wire pair (728) may be arranged in a coil form (not shown) or plurality of coil forms (not shown) or a bundled form (not shown) or combination thereof. This may allow a relative long section of said, at least one section of a twisted wire pair (728), to be used in a limited space. Furthermore, said coil form may be arranged to at least partially encircle an iron-core (not shown), for increased common mode noise suppression.

[0073] Preferably, said at least one section of a twisted wire pair (728) may be arranged to be exposed to radio frequency interference noise that may be generated by said light-bulb (500), during normal operation. Stated alternatively, said at least one section of a twisted wire pair (728) may preferably be un-shielded.

[0074] During normal operation, said at least one section of a twisted wire pair (728), may help to suppress, near field radiated common mode noise, that may be generated by said light-bulb (500), from coupling to the ac mains power wires (103; 104).It will be realised that, common mode noise may be suppressed via a noise cancelling effect, due to the alternating wire positions of said, at least one section of a twisted wire pair (728). Therefore, this invention discloses a method and system of reducing common mode noise for an un-grounded system, or without connecting to a ground (or earth) wire. As background information, a common mode choke may preferably require a connection, via one or more capacitors, (Y-capacitors), to a ground wire. Including said at least one section of a twisted wire pair (728), in accordance with this invention, may be a desirable solution to solve a complex problem, due to the low cost and low complexity of the design.

[0075] It will clearly be noted that in Fig. 3, all the mechanical intricate details of said light-bulb fitting (710) is not shown for clarity. Also, all the electrical intricate details of said light-bulb fitting (710) is not shown for clarity. The design of said light-bulb fitting (710) may be based on known prior art methods and systems. It will clearly be noted that in Fig. 3, all the mechanical intricate details of said light-bulb holder-socket (750) is not shown for clarity. Also, all the electrical intricate details of said light-bulb holder-socket (750) is not shown for clarity. The design of said light-bulb holder-socket (750) may be based on known prior art methods and systems.

[0076] Fig. 4 shows a simplified schematic diagram of another embodiment of a power saving device for a light-bulb (703), in accordance with the current subject matter, (see Fig. 4).

[0077] A power saving device for a light-bulb (703), arranged for reducing metered power usage, by suppressing common mode noise and differential mode noise, in accordance with the current subject matter, may comprise:

[0078] A light-bulb fitting (710) arranged for mechanical coupling to a lightbulb socket (not shown) and electrical coupling to said light-bulb socket (notshown). Said light-bulb fitting (710), may be arranged the same or similar to a prior art base structure of a light-bulb.

[0079] A light-bulb holder-socket (750), arranged for mechanical coupling to a base structure of a light-bulb (not shown) and electrical coupling to said base structure of a light-bulb (not shown).

[0080] At least one section of a twisted wire pair (728), wherein said at least one section of a twisted wire pair (728) may be arranged to transport electrical power between said light-bulb fitting (710) and said light-bulb holdersocket (750).

[0081] Preferably, said at least one section of a twisted wire pair (728) may be arranged in a coil form (not shown) or plurality of coil forms (not shown) or a bundled form (not shown) or combination thereof. This may allow a relative long section of said, at least one section of a twisted wire pair (728), to be used in a limited space. Preferably, said at least one section of a twisted wire pair (728) may be un-shielded.

[0082] And, at least one reactor (722), wherein one wire of said at least one section of a twisted wire pair (728), may be arranged electrically connected in series with said at least one reactor (722). It will be appreciated that said, at least one reactor (722), may be arranged as an iron-core reactor (not shown) or as an air-core reactor.

[0083] Normally, in an electric circuit, the order in which serially connected components are arranged may not matter. However, it will be noted that, preferably, said light-bulb holder-socket (750) may be directly electrically connected to, said at least one section of a twisted wire pair (728), as shown in Fig. 4. Mentioned ordering may allow for maximum suppression of radiated common mode noise.Fig. 5 shows a simplified schematic diagram of another embodiment of a power saving device for a light-bulb (704), in accordance with the current subject matter, (see Fig. 5).

[0084] A power saving device for a light-bulb (704), arranged for reducing metered power usage, by suppressing radiated common mode noise and conducted common mode noise, (or in general arranged for suppressing common mode noise), in accordance with the current subject matter, may comprise:

[0085] A light-bulb fitting (710) arranged for mechanical coupling to a lightbulb socket (not shown) and electrical coupling to said light-bulb socket (not shown). Said light-bulb fitting (710), may be arranged the same or similar to a prior art base structure of a light-bulb.

[0086] A light-bulb holder-socket (750), arranged for mechanical coupling to a base structure of a light-bulb (not shown) and electrical coupling to said base structure of a light-bulb (not shown).

[0087] At least one section of a twisted wire pair (728), wherein said at least one section of a twisted wire pair (728) may be arranged to transport electrical power between said light-bulb fitting (710) and said light-bulb holdersocket (750).

[0088] Preferably, said at least one section of a twisted wire pair (728) may be arranged in a coil form (not shown) or plurality of coil forms (not shown) or a bundled form (not shown) or combination thereof. Preferably, said at least one section of a twisted wire pair (728) may be un-shielded.And, at least one common mode choke (725), wherein said at least one common mode choke (725) may be electrically connected in series with said at least one section of a twisted wire pair (728).

[0089] It will be noted that, preferably, said light-bulb holder-socket (750) may be directly electrically connected to, said at least one section of a twisted wire pair (728), as shown in Fig. 5. Mentioned ordering may allow for maximum suppression of radiated common mode noise.

[0090] Referring to Fig. 1 and Fig. 2 and Fig. 3 and Fig. 4 and Fig. 5; it will clearly be noted that the term “light-bulb holder-socket (750)” is used for clarity, to differentiate between the terms “light-bulb holder-socket (750)” and “light-bulb socket (100)”.

[0091] Referring to Fig. 1 and Fig. 2 and Fig. 3 and Fig. 4 and Fig. 5; It will be apparent from a comparison of above mentioned Figs, that all disclosed embodiments (700) and (701) and (702) and (703) and (704) utilise a common feature, wherein, said power saving device for a light-bulb is operable arranged interposed between a light-bulb socket (100) and a light-bulb (500). Furthermore, all disclosed embodiments, (700) and (701) and (702) and (703) and (704) have a common object: to suppress common mode noise, or common mode noise and differential mode noise. This may help to save electrical power.

[0092] Referring to the description(s) of Fig. 3 and / or Fig. 4 and / or Fig. 5; as background information, it will be noted that a prior art twisted wire pair were not arranged in a coil form or a bundle form, as disclosed. Neither were a prior art twisted wire pair arranged in series with a common mode choke. A twisted wire pair, in accordance with the invention, may be arranged to use a variable twist rate, or continuously varying twist rate.As background, impedance is an important parameter in RF systems. At least one section of a twisted wire pair (728), in accordance with the invention, may purposely be arranged to cause an impedance mismatch for RFI, thereby further preventing RFI from coupling to ac mains power wires.

[0093] The invention is not limited to the disclosed embodiments, but may be varied within the scope of the claims.

[0094] Referring to Fig. 6 and Fig. 7; it will clearly be noted that Fig. 6 and Fig. 7, and their descriptions, are included for background information only, and will not be used to limit, interpret or restrict, this invention in any way.

[0095] Fig. 6 shows a schematic diagram of a test setup used to do a test measurement. A commercially available twisted wire pair (800) was electrically connected in series between an ac source and a commercially available LED light-bulb. An analogue oscilloscope was used to do measurements, arranged as shown in Fig. 6.

[0096] Fig. 7 shows a schematic diagram of approximately an oscilloscope picture from an analogue oscilloscope, indicative of the approximate voltage fall of common mode noise over a twisted wire pair (800), using the test setup shown in Fig. 6. The oscilloscope was set at 20mv / div. It will clearly be noted that results may depend on multiple factors and results may differ on a case-by-case basis.

[0097] The same setup was used to test a commercially available LED light-bulb with an active harmonic filter (AHF). Although mentioned AHF may help to suppress low frequency harmonics, the results (not shown) displayed high frequency noise, of approximately slightly lower amplitude as shown in Fig. 7, and with multiple “ghost images” of approximately double mentioned slightly lower amplitude, that may be attributed to common mode noise SH components.

Claims

The invention claimed is:

1. A power saving device for a light-bulb, comprising:a light-bulb fitting (710) arranged for insertion into a light-bulb socket (100), wherein said light-bulb fitting (710) is arranged for mechanical and electrical coupling to said light-bulb socket (100);a light-bulb holder-socket (750), arranged for receiving a light-bulb (500), wherein said light-bulb holder-socket (750) is arranged for mechanical and electrical coupling to said light-bulb (500); anda means for suppressing common mode noise, or common mode noise and differential mode noise, wherein said means is further arranged to transport electrical power between said light-bulb fitting (710) and said light-bulb holder-socket (750).

2. A power saving device for a light-bulb, arranged for suppressing near field radio frequency interference, comprising:a light-bulb fitting (710) arranged for insertion into a light-bulb socket (100), wherein said light-bulb fitting (710) is arranged for mechanical (714) and electrical (711, 712) coupling to said light-bulb socket (100); a light-bulb holder-socket (750), arranged for receiving a light-bulb (500), wherein said light-bulb holder-socket (750) is arranged for mechanical (754) and electrical (751, 752) coupling to said light-bulb (500); and at least one section of a twisted wire pair (728), wherein said at least one section of a twisted wire pair (728) is arranged to transport electrical power between said light-bulb fitting (710) and said light-bulb holdersocket (750).

3. A power saving device for a light-bulb, arranged for suppressing common mode noise and differential mode noise, comprising:a light-bulb fitting (710) arranged for mechanical coupling to a light-bulb socket and electrical coupling to said light-bulb socket;a light-bulb holder-socket (750), arranged for mechanical coupling to a base structure of a light-bulb and electrical coupling to said base structure of a light-bulb;at least one section of a twisted wire pair (728), wherein said at least one section of a twisted wire pair (728) is arranged to transport electrical power between said light-bulb fitting (710) and said light-bulb holdersocket (750); andat least one reactor (722), wherein one wire of said at least one section of a twisted wire pair (728), is arranged electrically connected in series with said at least one reactor (722).

4. A power saving device for a light-bulb, arranged for suppressing radiated common mode noise and conducted common mode noise, comprising: a light-bulb fitting (710), arranged for mechanical coupling to a light-bulb socket and electrical coupling to said light-bulb socket;a light-bulb holder-socket (750), arranged for mechanical coupling to a base structure of a light-bulb and electrical coupling to said base structure of a light-bulb;at least one section of a twisted wire pair (728), wherein said at least one section of a twisted wire pair (728) is arranged to transport electrical power between said light-bulb fitting (710) and said light-bulb holdersocket (750); andat least one common mode choke (725), wherein said at least one common mode choke (725) is electrically connected in series with said at least one section of a twisted wire pair (728).

5. The device of claim 1 , further arranged to promote a third party.

6. The device of claim 2, wherein, said at least one section of a twisted wire pair (728) is arranged in a coil form or plurality of coil forms or a bundled form or combination thereof.

7. The device of claim 3, wherein, said at least one section of a twisted wire pair (728) is arranged in a coil form or plurality of coil forms or a bundled form or combination thereof.

8. The device of claim 4, wherein, said at least one section of a twisted wire pair (728) is arranged in a coil form or plurality of coil forms or a bundled form or combination thereof.

9. The device of claim 3, wherein said light-bulb holder-socket (750) is directly electrically connected to said at least one section of a twisted wire pair (728).

10. The device of claim 4, wherein said light-bulb holder-socket (750) is directly electrically connected to said at least one section of a twisted wire pair (728).

Images