CN2609318Y - Electronic transformer for low voltage lamp - Google Patents

Abstract

The utility model discloses an electronic transformer for low voltage lamp, relating to an improvement of electronic transformer suitable for direct-lighting wire lamp or rail lamp. The utility model applies a multilevel protective circuit to secure the user, and a synchronous full wave rectifying circuit(5) to synchronously rectify the high frequency low-tension current; therefore, the output 100Hz frequency is closed to the unidirectional semiwave of the sine alternating current to envelope the voltage wave form unidirectional pulse voltage to the loading. The utility model has a good electromagnetic compatibility and is accordance with the IEC standard; the transfer efficiency rectifying machine is equal or more than 93 percent; in the same end voltage, the same loading and supply line, the utility model is little in transmission loss in the wire, and the voltage is reduced and the output line can last 20 meter. The utility model is light, small and environmental; the utility model also has the advantages of great energy-saving function, low cost and convenience in storing and delivering as well as secure in installation. The utility model can completely take place of the traditional transformer to be applied in the wire lamp or rail lamp.

Description

A kind of novel low pressure electronic lamp transformer

Technical field

A kind of novel low pressure electronic lamp transformer relates to the improvement of electronic transformer, is applicable to Linear light, the track lamp of projection illumination.

Background technology

At present as the Linear light of projection illumination, the lighting source of track lamp, usually adopt the low pressure quartz tungsten halogen lamp, because its color rendering index height, light is logical, and to keep performance good, be widely used in various places such as commerce, household, but its normal just use must be equipped with corresponding transformer, converts line voltage to 12V (or 24V) low-voltage and isolates power supply.Silicon steel sheet transformer (the EI type that corresponding traditional type is arranged on the market now; annular) and electronic transformer; its good stability of traditional transformer; electromagnetic interference is little, and the length of output line is (because being power-frequency voltage) without limits, and the output line voltage landing is with general electrical network; but the volume of traditional transformer is bigger; weight is also heavier, and power consumption lacks defencive function.And existing electronic transformer, though it is little to have volume, in light weight, conversion efficiency is wanted high characteristic, but it is to installation environment, to output line limited length system, and because output voltage is a high-frequency ac voltage, spacing electromagnetic radiation increases, and length surpasses a timing (generally being no more than 2 meters), because high-frequency ac coupling equivalent induction reactance is mapped to the primary circuit of transformer by transformer, can influence the operate as normal of circuit of primary side, gently then temperature rise is increased, and is heavy then cause the change of entire circuit operating state and complete machine is burnt, in addition, because electric current is a high-frequency ac current, electrical wiring is long, and the induction reactance that causes can be greatly greater than impedance, make voltage sharply reduce and make illuminance wretched insufficiency, transformer stable undesirable away from the light fixture of transformer.This type of electronic transformer; in order to reduce production costs; generally adopt the half-bridge inversion circuit of magnet ring feedback; in order to improve reliability; improve the grade; meet international standards, also circuit is improved, all designed overload; short-circuit protection circuit; for reaching the mandatory requirement of light fixture series products Electro Magnetic Compatibility, also increased EMI in input stage, break through circuit devcies such as absorber; also tending to consistent on the cost price with on the cost price of traditional transformer; but, however, be used in the Linear light of projection illumination in the current industry; track lamp; all adopt the toroidal transformer or the EI deformation depressor of traditional type; and can not use electronic transformer, its chief reason is the length of transmission line considerably beyond 2 meters, the good stability of transformer.

Summary of the invention

At the deficiency of above-mentioned transformer, the inventor proposed through studying for a long period of time a kind of can be used for long apart from feed, in light weight, volume is little, conversion efficiency is high, have multinomial defencive function, environmental protection and energy saving, meets the electronic transformer of relevant international standard.

The utility model is by the EMI filter circuit; bridge rectifier; overvoltage crowbar; the DC/AC high-frequency conversion circuit; high frequency transformation coil; the all-wave circuit of synchronous rectification; circuits for triggering; thermal-shutdown circuit; overload, short-circuit protection circuit and current sampling circuit constitute; the all-wave circuit of synchronous rectification is connected to form by the primary side in rectifying tube, coil, resistance, electric capacity and the high frequency transformation coil, and electric current is carried out all-wave synchronous rectification, and several electric capacity of wherein doing further filtering can carry out the Y connection or adopt alternate manner to connect.In the utility model when work,, after the filtering of EMI filter circuit, bridge rectifier becomes high voltage direct current with alternating current through the electric current fuse in the alternating current input; Circuits for triggering work produces trigger impulse and makes the work of DC/AC high-frequency conversion circuit, high-frequency AC voltage is converted to the high-frequency AC low-voltage and the all-wave circuit of synchronous rectification of isolation through high frequency transformation coil through being connected with its primary side, the output envelope contains the unidirectional pulsating voltage of unidirectional half-wave parabolic envelope voltage waveform of the 100Hz near sinusoidal alternating current of 40～50KHZ first-harmonic after the synchronous rectification, be that Rectified alternating current is defeated by load, make the voltage of output not too large, being equal to power-frequency voltage falls, feeder line length can reach 20 meters, applicable to the cabling light fixture, the long distance of track lamp is lighted light fixture fully.Current sampling circuit can take out the excess temperature signal that causes because of overload, over-current signal that short circuit causes, overvoltage signal that overvoltage causes and excess temperature and drive overload, short-circuit protection circuit work; breaking circuit makes circuits for triggering not produce trigger impulse and circuit working is stopped.

Advantage of the present utility model is: owing to adopted all-wave circuit of synchronous rectification and multinomial protective circuit, make the utility model electronic transformer:

1. high-power in being applicable to, output line can reach 20 meters, and output voltage falls not too largely, is equal to power-frequency voltage and falls, and is applicable to the cabling light fixture fully, and track lamp can be grown distance and light light fixture, has overcome the deficiency of existing electronic transformer.

2. electromagnetic compatibility can be good, meets the IEC relevant criterion, as: EN55015 EN61000 etc.

3. efficient height, complete machine conversion efficiency 〉=93%, defencive function is complete, and is safe to use.

4. under same port voltage, identical load and feeder line length, its circuit loss is little, and pressure drop is low, and the output voltage peak value reduces half, and effectively reduces the reduction electromagnetic radiation.

5. have in light weight, volume is little, environmental protection, energy-saving effect and the utilization of resources are good, price is suitable, storage, fortune are easy, user installation safety, convenience.Use the complete alternative traditional transformer of the utility model electronic transformer as the cabling light fixture, the transformer that track lamp is complementary.

Description of drawings

Accompanying drawing 1 is the utility model embodiment schematic diagram.

Embodiment

The utility model is described in further detail for the contrast accompanying drawing.The utility model is by EMI filter circuit 1, bridge rectifier 2, overvoltage crowbar 3; DC/AC high-frequency conversion circuit 4, high frequency transformation coil L1, all-wave circuit of synchronous rectification 5; circuits for triggering 6, thermal-shutdown circuit 7, overload, short-circuit protection circuit 8 and current sampling circuit 9 constitute.Wherein all-wave circuit of synchronous rectification 5 is connected with secondary side coil among the high frequency transformation coil L1, it is by rectifying tube Q1, Q2, resistance R 1, R2, R3, R4, R5, R6, capacitor C 1, C2, C3, C4, C5, coil L2, rectifying tube Z1, Z2, Z3, Z4 connects to form, rectifying tube Q1, Q2 adopts metal-oxide-semiconductor, rectifying tube Q1 and resistance R 1, R2, the end of Z1, the other end with R2, the end of R3, with capacitor C 1, one utmost point of high frequency transformation coil L1 primary side connects, rectifying tube Q2 and resistance R 4, R5, the end of Z3, the other end with R5, the end of R6 and Z4 is connected with an end of capacitor C 2 and another utmost point of high frequency transformation coil L1 primary side.An end of making capacitor C 3, the C4 of further filtering is connected with the two poles of the earth of the primary side of high frequency transformation coil L1 respectively, and their other end is connected as Y with an end of the capacitor C 5 of doing further filtering, the other end ground connection of capacitor C 5.The other end of resistance R 1 is connected with the end of coil L2, and the other end of coil L2 is connected with the other end of resistance R 6.The other end of capacitor C 1 is connected with the other end of resistance R 3, and the other end of capacitor C 2 is connected with the other end of resistance R 4.The other end of the end of the other end of resistance R 2 and Z2, Z3 and the Q1 other end and resistance R 3, R4 is connected.The other end of Z1 is connected with the other end of Z2, and the other end of Z3 is connected with the other end of Z4.The input of the utility model when work alternating current through the electric current fuse after 1 filtering of EMI filter circuit, bridge rectifier 2 become high voltage direct current with alternating current; Circuits for triggering 6 work produce trigger impulse and make 4 work of DC/AC high-frequency conversion circuit, high-frequency AC voltage is converted to the high-frequency AC low-voltage of isolation and comes the conducting of driven MOS pipe Q1, Q2 and end through high frequency transformation coil L1 through the voltage that the all-wave circuit of synchronous rectification 5 that is connected with its primary side drives the winding generation synchronously by high frequency transformation coil L1 built-in, floating ground drives from dividing potential drop, realize that the identical time with secondary voltage opens and end, the parabolic envelope pulsation wave direct voltage of output 100Hz after synchronous rectification, long distance is lighted Linear light tool, track lamp.Current sampling circuit 9 can take out the excess temperature signal that excess temperature that the overvoltage signal that causes because of overload, over-current signal that short circuit causes, overvoltage that overvoltage crowbar 3 records and thermal-shutdown circuit 7 record causes and drive overload, short-circuit protection circuit 8 work; breaking circuit quits work electronic transformer.

Claims (3)

1. novel low pressure electronic lamp transformer, by EMI filter circuit (1), bridge rectifier (2), overvoltage crowbar (3), DC/AC high-frequency conversion circuit (4), high frequency transformation coil L1, all-wave circuit of synchronous rectification (5), circuits for triggering (6), thermal-shutdown circuit (7), overload, short-circuit protection circuit (8) and current sampling circuit (9) constitute, it is characterized in that: all-wave circuit of synchronous rectification (5) is connected with secondary side coil among the high frequency transformation coil L1, it is by rectifying tube Q1, Q2, resistance R 1, R2, R3, R4, R5, R6, capacitor C 1, C2, C3, C4, C5, coil L2, rectifying tube Z1, Z2, Z3, Z4 connects to form, wherein, rectifying tube Q1 and resistance R 1, R2, the end of Z1 is with the other end of R2, the end of R3 is with capacitor C 1, one utmost point of high frequency transformation coil L1 primary side connects; The end of rectifying tube Q2 and resistance R 4, R5, Z3, the end with the other end, R6 and the Z4 of R5 is connected with an end of capacitor C 2 and another utmost point of high frequency transformation coil L1 primary side; The end of capacitor C 3, C4 is connected with the two poles of the earth of the primary side of high frequency transformation coil L1 respectively, and their other end is connected as Y with an end of capacitor C 5, the other end ground connection of capacitor C 5; The other end of resistance R 1 is connected with the end of coil L2, and the other end of coil L2 is connected with the other end of resistance R 6; The other end of capacitor C 1 is connected with the other end of resistance R 3, and the other end of capacitor C 2 is connected with the other end of resistance R 4; The other end of the end of the other end of resistance R 2 and Z2, Z3 and the Q1 other end and resistance R 3, R4 is connected; The other end of Z1 is connected with the other end of Z2, and the other end of Z3 and the other end of Z4 connect and compose.

2. electronic transformer according to claim 1 is characterized in that: the electric capacity of doing further filtering in the all-wave circuit of synchronous rectification (5) can adopt other modes to connect.

3. electronic transformer according to claim 1 is characterized in that: Q1, Q2 can adopt metal-oxide-semiconductor.