A kind of drive electric power unit of ballast formula LED lamp
Technical field
The utility model relates to a kind of driving power of solid luminous lamp, more particularly, relates to a kind of drive electric power unit of ballast formula LED lamp.
Background technology
The LED semiconductor lighting is the new industry that State Council accelerates cultivation and development strategy.In the recent period, the Department of Science and Technology has worked out " semiconductor lighting development in science and technology " 12 " ad hoc planning ", in the application technical research of the key task of ad hoc planning, has proposed efficient, low-cost, the highly reliable LED driving power of exploitation.This has illustrated the importance of LED driving power in the technology of semiconductor illumination application field.
The LED driving power mainly contains alternating current 220V civil power supply load after commutation inversion is used at present, the most frequently used rectifier system is transformed to direct current by the rectifier bridge that 4 diodes form with alternating current, become controlled direct current through after inversion again, supply with the LED lamp.The shortcoming of this method is, the non-linear of DC transfer circuit that forms due to diode and electric capacity can produce a large amount of current harmonics and reactive power, causes the pollution of electrical network.This harmonic pollution not only can make the line voltage distorted, but also can cause fault and the damage of power consumption equipment.Therefore, need to take very complicated means that the waveform of input current is approached sinusoidal wave.This complex process can exert an influence to the useful life of LED driving power naturally.LED is widely used with its environmental protection, luminous efficient characteristics, especially uses more and more extensive aspect illumination.With regard to present development, what everybody was concerned about the most is the life problems of lamp, and be that lamp user or factory are all seen now, the life-span of lamp is depended on driving power, lamp failure more than 99% is all because driving power causes, the life-span of LED reaches 50000h, so but with it the life-span of supporting driving power only for 10000h. LED lamp lighting apparatus can application one of key link be its driving power problem.For the problem that prior art exists, Chinese patent application publication No. CN102523674A has proposed the brand new technical scheme of the driving power of ballast formula LED lamp, uses the driving power of ballast formula LED lamp to have following advantage:
1, oneself power consumption is little, temperature rise is low, long service life.These characteristics are above-mentioned patented technology advanced places compared with prior art, the little energy efficiency factor that can improve system of oneself power consumption in These characteristics; The low characteristic of temperature rise is particularly important for the LED lamp, what well-known LED lamp was feared most is exactly temperature rise, if the temperature rise of LED lamp is very high, add the high temperature rise driving power, the performance of lamp will sharply descend (prior art is all like this), uses the driving power of ballast formula LED lamp, and the temperature rise Δ t of the element Inductive ballast that it can generate heat can be controlled in 10 degree, the driving power of the LED lamp of this specific character will improve the combination property of LED lamp greatly; Useful life, because the temperature rise of Inductive ballast is extremely low, useful life that so Inductive ballast has very long (foundation was IEC920 ballast working temperature and concerned chart useful life at least 50 years), capacitor in circuit is according to national GB/T18504-2001 relevant regulations, and the life-span of its continuous operation is at least 10 years.
2, to satisfy requirement, the functional reliability of LED lamp fully high for superior performance.The driving power of ballast formula LED lamp has the characteristic of relatively constant electric current and dynamic voltage adjustment, and the function of dynamic voltage adjustment is that underload (as 1 LED lamp) and full load (being a plurality of LED lamps as nominal load power) LED lamp can work.And the driving power of the LED lamp of prior art is due to certain LED because the quality reason of self is damaged thereby form short circuit, and its original voltage drop is just married again on other LED lamps, can make other LED lamps also will be because overvoltage damages.Because the element of the driving power rapid wear of ballast formula LED lamp of the present invention is few, the reliability of work will improve greatly.
3 harmonic contents are few.The driving power of ballast formula LED lamp is electric capacity and inductance series circuit, and electric capacity coordinates with inductance, makes the current waveform of circuit approach sine wave, and shape factor is in 1.5 left and right, and is so harmonic content is few, pollution-free to electrical network.
The rule of development of new things is that good technology is all to produce by continuous perfect process, patent application of the present invention, be for prior art public announcement of a patent application number for the driving power of the ballast formula LED lamp of CN102523674A input voltage during in wide variation (as 160V~250V), the deficiency that the electric current of drive circuit also can change proposes.
Summary of the invention
In view of the defects that prior art exists, the utility model provides a kind of driving power that can adapt to the ballast formula LED lamp of wide voltage.
In order to achieve the above object, the utility model is taked following technical scheme: the drive electric power unit of ballast formula LED lamp, comprise Inductive ballast L, the first capacitor C, and it is characterized in that:
The two ends of said the first capacitor C are the series circuit that L end and node 1 end are connected to route the 4th a capacitor C a and the first K switch a composition at least;
The power input of the drive electric power unit of said ballast formula LED lamp is L end, N end, goes back and be connected with the circuit arrangement DJ that drives the first K switch a state conversion when input voltage changes.
Said the first K switch a state switching circuit device DJ comprises the executive circuit of power supply circuits, sample circuit, drive signal circuit, drive circuit, state conversion
The power supply circuits of said the first K switch a state switching circuit device DJ comprise:
Capacitance decompression element the second capacitor C 1, the first resistance R, the first unidirectional element D1, the second unidirectional element D2, voltage stabilizing element W, filter element the 3rd capacitor C 2, described the second capacitor C 1 and a termination power input L after the first resistance R is in parallel, other end D1 negative pole are connected contact and are connected with the D2 positive pole, the positive pole of D1 connects the N end of power input, the negative pole of D2 links with an end of the shunt circuit of W and C2, the N end of another termination power input of W, C2 shunt circuit;
The sample circuit of said the first K switch a state switching circuit device DJ comprises:
The 3rd unidirectional element Da1, the 8th capacitor C a1, the second resistance R a1, the 3rd resistance R a2, the 4th resistance R a3, after described Da1, Ra1, Ra2, Ra3 connect mutually, an end is connected with the L end of power supply input, the other end is connected with the N end of power supply input, the end of Ca1 is connected with the negative pole of Da1 and the tie point of Ra1, and the other end of Ca1 connects with the N end of power supply input;
The drive signal circuit of said the first K switch a state switching circuit device DJ comprises:
The first integrated circuit die I Ca and the 9th capacitor C a2, the 5th resistance R a4, the power input of described ICa connects the A point of described power supply circuits, high-triggering end is connected with the tie point of Ra1, Ra2, low triggering end connects the center tap terminal of Ra3, output termination Ra4, control end connects the N end of power supply input by Ca2, common is connected with the N end of power supply input;
The executive circuit of the drive circuit of said the first K switch a state switching circuit device DJ and state conversion comprises:
Driving element the first transistor GBa, state conversion executive component the first relay J a, the 4th unidirectional element Da2, the base stage of described Gba meets Ra4, collector electrode is connected with the end of Ja, emitter is connected with the N end of power supply input, the other end of Ja is connected with the A of power supply circuits point, and Da2 also is connected in the two ends of Ja.
The series circuit that the 5th capacitor C b and second switch Kb form and the two ends that are connected in C are that the series circuit that forms of L end and node 1 end, the 6th capacitor C c and the 3rd K switch c and the two ends that are connected in C are that the series circuit that forms of L end and node 1 end, the 7th capacitor C d and the 4th K switch d and the two ends that are connected in C are that L holds and node 1 end;
Said the first K switch a state switching circuit device DJ also comprises: the sample circuit that drives the sample circuit of Kb state conversion, the sample circuit that drives the conversion of Kc state, the conversion of driving Kd state;
The power supply circuits two ends of said the first K switch a state switching circuit device DJ are the executive circuit that drive signal circuit, drive circuit and the state of executive circuit, Kd of drive signal circuit, drive circuit and state conversion of executive circuit, the Kc of the N of node A and power supply input drive signal circuit, drive circuit and the state conversion of hold and be connected with Kb changed.
The sample circuit of said driving second switch Kb state conversion comprises the 5th unidirectional element Db1, the tenth capacitor C b1, the 6th resistance R b1, the 7th resistance R b2, the 8th resistance R b3, after described Db1, Rb1, Rb2, Rb3 connect mutually, an end is connected with the L end of power supply input, the other end is connected with the N end of power supply input, the negative pole of the end Db1 of Cb1 and the tie point of Rb1 are connected, and the other end of Cb1 connects with the N end of power supply input;
The drive signal circuit of said second switch Kb state conversion comprises the second integrated circuit die I Cb and the 11 capacitor C b2, the 9th resistance R b4, the power input of described ICb connects the A point of described power supply circuits, high-triggering end is connected with the tie point of Rb1, Rb2, low triggering end connects the center tap terminal of Rb3, output termination Rb4, control end connects the N end of power supply input by Cb2, common is connected with the N end of power supply input;
The executive circuit of the drive circuit of said second switch Kb state conversion and state conversion comprises driving element transistor seconds GBb, state conversion executive component the second relay J b, Db2, described GBb base stage connects the Rb4 collector electrode and is connected with the end of Jb, emitter is connected with the N end of power supply input, the other end of Jb is connected with the A of power supply circuits point, and Db2 also is connected in the two ends of Jb;
The sample circuit of said driving the 3rd K switch c state conversion comprises the 7th unidirectional element Dc1, the 12 capacitor C c1, the tenth resistance R c1, the 11 resistance R c2, the 12 resistance R c3, after described Dc1, Rc1, Rc2, Rc3 connect mutually, an end is connected with the L end of power supply input, the other end is connected with the N end of power supply input, the end of Cc1 is connected with the negative pole of Dc1 and the tie point of Rc1, and the other end of Cc1 connects with the N end of power supply input;
The drive signal circuit of said the 3rd K switch c state conversion comprises the 3rd integrated circuit die I Cc and the 13 capacitor C c2, the 13 resistance R c4, the power input of described ICc connects the A point of described power supply circuits, high-triggering end is connected with the tie point of Rc1, Rc2, low triggering end connects the center tap terminal of Rc3, output termination Rc4, control end connects the N end of power supply input by Cc2, common is connected with the N end of power supply input;
The executive circuit of the drive circuit of said the 3rd K switch c state conversion and state conversion comprises driving element the 3rd transistor GBc, state conversion executive component the 3rd relay J c, the 8th unidirectional element Dc2, described GBc base stage meets Rc4, collector electrode is connected with the end of Jc, emitter is connected with the N end of power supply input, the other end of Jc is connected with the A of power supply circuits point, and Dc2 also is connected in the two ends of Jc;
The sample circuit of said the 4th K switch d state conversion comprises the 9th unidirectional element Dd1, the 14 capacitor C d1, the 14 resistance R d1, the 15 resistance R d2, the 16 resistance R d3, after described Dd1, Rd1, Rd2, Rd3 connect mutually, an end is connected with the L end of power supply input, the other end is connected with the N end of power supply input, the end of Cd1 is connected with the negative pole of Dd1 and the tie point of Rd1, and the other end of Cd1 connects with the N end of power supply input;
The drive signal circuit of said the 4th K switch d state conversion comprises the 4th integrated circuit die I Cd and the 15 capacitor C d2, the 17 resistance R d4, the power input of described ICd connects the A point of described power supply circuits, high-triggering end is connected with the tie point of Rd1, Rd2, low triggering end connects the center tap terminal of Rd3, output termination Rd4, control end connects the N end of power supply input by Cd2, common is connected with the N end of power supply input;
The drive circuit of said the 4th K switch d state conversion and executive circuit comprise driving element the 4th transistor GBd, state conversion executive component the 4th relay J d, the tenth unidirectional element Dd2, the base stage of described GBd meets Rd4, collector electrode is connected with the end of Jd, emitter is connected with the N end of power supply input, the other end of Jd is connected with the A of power supply circuits point, and Dd2 also is connected in the two ends of Jd.
The utility model has the advantage of, the driving power that he has realized ballast formula LED lamp is in very wide input voltage range (within the variation as 160V~250V), keep the electric current substantially constant of LED lamp, can realize that as required the curent change of lamp is less than ± 5% to ± 3%.This advantage adds the technical characterictic of the dynamic voltage adjustment (can think the constant-current source irrelevant with load voltage) of the driving power of ballast formula LED lamp, and high efficiency (efficient can reach 95% to 97%) technical characterictic, particularly dynamic voltage adjustment technical characterictic of the driving power of ballast formula LED lamp are the main advantages that existing LED Driving technique can't realize.These technical characterictics will make the driving power of ballast formula LED lamp become the developing direction of following illuminating LED lamp driving power.
Description of drawings
Fig. 1, be the circuit structure schematic diagram of the drive electric power unit of ballast formula LED lamp of the present utility model.
Fig. 2, be the part circuit structure schematic diagram of the drive electric power unit of ballast formula LED lamp of the present utility model.
Fig. 3, be the local circuit structure principle chart of the drive electric power unit of ballast formula LED lamp of the present utility model.
Fig. 4, be the local circuit structure principle chart of the drive electric power unit of another kind of ballast formula LED lamp of the present utility model.
Embodiment
Below in conjunction with accompanying drawing, the utility model is done further carefully to state.
Referring to Fig. 1, the circuit structure schematic diagram of the driving power of ballast formula LED lamp of the present utility model, the two ends of the first shown capacitor C are the series circuit that L end and node 1 termination are comprised of route the 4th a capacitor C a and the first K switch a.As shown in Figure 1, under specified input voltage, the capacity of Inductive ballast L series capacitance is C, in figure, the power input of the drive electric power unit of ballast formula LED lamp be L end and node 1 end also and be connected with the circuit arrangement DJ that driving the first K switch a state is changed when input voltage changes.
Shown in Figure 2 is the part circuit structure schematic diagram of the circuit arrangement DJ of the first K switch a state conversion.The executive circuit of the state conversion of the power supply circuits of the circuit arrangement DJ that the first K switch a state that there is shown is changed, sample circuit, drive signal circuit, drive circuit, relay (Ja).
Power supply circuits shown in figure comprise:
Capacitance decompression element the second capacitor C 1, the first resistance R, the first unidirectional element D1, the second unidirectional element D2, voltage stabilizing element W, filter element the 3rd capacitor C 2, described the second capacitor C 1 and a termination power input L after the first resistance R is in parallel, other end D1 negative pole are connected contact and are connected with the D2 positive pole, the positive pole of D1 connects the N end of power input, the negative pole of D2 links with an end of the shunt circuit of W and C2, the N end of another termination power input of W, C2 shunt circuit.
The sample circuit of the circuit arrangement DJ of the first K switch a state conversion shown in figure comprises:
The 3rd unidirectional element Da1, the 8th capacitor C a1, the second resistance R a1, the 3rd resistance R a2, the 4th resistance R a3, after described Da1, Ra1, Ra2, Ra3 connect mutually, an end is connected with the L end of power supply input, the other end is connected with the N end of power supply input, the end of Ca1 is connected with the negative pole of Da1 and the tie point of Ra1, and the other end of Ca1 connects with the N end of power supply input.
The drive signal circuit of the circuit arrangement DJ of the first K switch a state conversion shown in figure comprises:
The first integrated circuit die I Ca and the 9th capacitor C a2, the 5th resistance R a4, the power input of described ICa connects the A point of described power supply circuits, high-triggering end is connected with the tie point of Ra1, Ra2, low triggering end connects the center tap terminal of Ra3, output termination Ra4, control end connects the N end of power supply input by Ca2, common is connected with the N end of power supply input;
The drive circuit of the circuit arrangement DJ of the first K switch a state conversion shown in figure and the executive circuit of state conversion comprise:
Driving element the first transistor GBa, state conversion executive component the first relay J a, the 4th unidirectional element Da2, the base stage of described Gba meets Ra4, collector electrode is connected with the end of Ja, emitter is connected with the N end of power supply input, the other end of Ja is connected with the A of power supply circuits point, and Da2 also is connected in the two ends of Ja.
The operation principle of above-mentioned circuit illustrated in figures 1 and 2 is: when input added specified alternating voltage, capacitor C+Ca, Inductive ballast L and converter circuit provided condition of work to the LED lamp.Because electric power system can not provide constant operating voltage, when input terminal voltage changes, LED lamp system electric current also can change along with change in voltage, and the setting of Fig. 1 and Fig. 2 circuit is for when input terminal voltage significantly changes, and reduces the curent change of LED lamp system.The below carefully states the working condition of each element circuit:
Sample circuit obtains the amount that input voltage changes, this variable is added to the trigger end of the first integrated circuit die I Ca of drive signal circuit, ICa is the Schmidt trigger that 555 timers consist of, high-triggering end is 6 pin of the threshold voltage TH (ICa) of trigger namely, and the logical circuit of this value is 0, and output 3 pin that reach this value ICa are 0, driving element the first transistor GBa base potential is 0, relay J a does not work without electricity, and Ka is normally open.When input voltage during lower than the trigger voltage of set low triggering end, 2 pin of the trigger voltage TR of trigger (ICa) namely, drive signal circuit upset, the logical circuit of ICa output 3 pin is that 1, GBa base stage is high potential, the GBa saturation conduction, Ja gets electric adhesive, the Ka dynamic circuit connector.According to above-mentioned logical relation, the result that obtains is when input terminal voltage raises, and corresponding is the low capacity capacitor C, and visible the technical solution of the utility model has solved the problem that raises and cause circuital current to increase due to input terminal voltage.According to above-mentioned logical relation equally as can be known, when input terminal voltage reduced, that corresponding was jumbo capacitor C+Ca, and visible the technical solution of the utility model has solved because input terminal voltage reduces the problem that causes circuital current to reduce.8 pin of ICa are positive source VC, and 4 pin of ICa are forced resetting end MR, and the present embodiment is that 4 pin forced resetting end MR are met positive supply VC together with 8 pin, and 1 pin of ICa connects common.In the circuit of Fig. 2, regulate Ra2 and Ra3 threshold voltage TH and trigger voltage TR can be set.When 5 pin of ICa add control voltage, can change the return difference characteristic of trigger, thereby obtain different switching levels, the present embodiment is control end to be connect the N end of power supply input, i.e. fixing return difference characteristic by Ca2.The drive circuit that the present embodiment uses considers that the efficiency of the drive electric power unit that is conducive to improve ballast formula LED lamp arranges, if use SE555 can save drive circuit, because the output current of SE555 is 200mA, can directly drive relay J a, the Icc of SE555 is 15mA when Ucc=15V, therefore own loss has selected the negligible ICM7555 of own loss up to 0.225W the present embodiment, so used the drive circuit of transistor GBa as relay J a.The power supply circuits of the circuit arrangement DJ of K switch a state conversion are that the executive circuit for the state conversion of drive signal circuit, drive circuit, relay J a provides needed electric energy.In the circuit of Fig. 2, capacitor C a1 is filter capacitor, and Da2 is when relay J a dead electricity, eliminates induced potential, protective transistor GBa.
Shown in Figure 3 is the local circuit structure principle chart of the drive electric power unit of ballast formula LED lamp.The series circuit that forms at the 5th capacitor C b and second switch Kb shown in figure and the two ends that are connected in C are that the series circuit that forms of L end and node 1 end, the 6th capacitor C c and the 3rd K switch c and the two ends that are connected in C are that the series circuit that forms of L end and node 1 end, the 7th capacitor C d and the 4th K switch d and the two ends that are connected in C are that L holds and node 1 end.The actuator of the driving power of the ballast formula LED lamp that the same Fig. 1 of local circuit structure shown in this figure, Fig. 4 are constant current of the present utility model together, the driving power that can adapt to the ballast formula LED lamp of wide voltage relies on him to realize.There is shown the series circuit that another three routing capacitances of the series circuit that forms except capacitor C a and K switch a and switch form, is respectively the series circuit of series circuit, capacitor C c and K switch c that capacitor C b and K switch b the form series circuit, capacitor C d and the K switch d composition that form.Its operation principle is identical with Fig. 1.
shown in Figure 4 is the local circuit structure principle chart of the drive electric power unit of the bright another kind of ballast formula LED lamp of utility model, the sample circuit of the driving second switch Kb state conversion shown in figure comprises the 5th unidirectional element Db1, the tenth capacitor C b1, the 6th resistance R b1, the 7th resistance R b2, the 8th resistance R b3, described Db1, Rb1, Rb2, after Rb3 connects mutually, an end is connected with the L end of power supply input, the other end is connected with the N end of power supply input, the negative pole of the end Db1 of Cb1 and the tie point of Rb1 are connected, the other end of Cb1 connects with the N end of power supply input.The drive signal circuit of the second switch Kb state conversion shown in figure comprises the second integrated circuit die I Cb and the 11 capacitor C b2, the 9th resistance R b4, the power input of described ICb connects the A point of described power supply circuits, high-triggering end is connected with the tie point of Rb1, Rb2, low triggering end connects the center tap terminal of Rb3, output termination Rb4, control end connects the N end of power supply input by Cb2, common is connected with the N end of power supply input.The drive circuit of the second switch Kb state conversion shown in figure and the executive circuit of state conversion comprise driving element transistor seconds GBb, state conversion executive component the second relay J b, Db2, described GBb base stage meets Rb4, collector electrode is connected with the end of Jb, emitter is connected with the N end of power supply input, the other end of Jb is connected with the A of power supply circuits point, and Db2 also is connected in the two ends of Jb.The power supply of the executive circuit of the drive signal circuit of this circuit, drive circuit, state conversion is provided by power supply circuits shown in Figure 2.The operation principle of this control unit is basic identical with Fig. 2, and the threshold voltage TH that just arranges is different with trigger voltage TR.
The sample circuit of driving the 3rd K switch c state conversion shown in figure comprises the 7th unidirectional element Dc1, the 12 capacitor C c1, the tenth resistance R c1, the 11 resistance R c2, the 12 resistance R c3, after described Dc1, Rc1, Rc2, Rc3 connect mutually, an end is connected with the L end of power supply input, the other end is connected with the N end of power supply input, the end of Cc1 is connected with the negative pole of Dc1 and the tie point of Rc1, and the other end of Cc1 connects with the N end of power supply input.The drive signal circuit of the 3rd K switch c state conversion shown in figure comprises the 3rd integrated circuit die I Cc and the 13 capacitor C c2, the 13 resistance R c4, the power input of described ICc connects the A point of described power supply circuits, high-triggering end is connected with the tie point of Rc1, Rc2, low triggering end connects the center tap terminal of Rc3, output termination Rc4, control end connects the N end of power supply input by Cc2, common is connected with the N end of power supply input.The drive circuit of the 3rd K switch c state conversion shown in figure and the executive circuit of state conversion comprise driving element the 3rd transistor GBc, state conversion executive component the 3rd relay J c, the 8th unidirectional element Dc2, described GBc base stage meets Rc4, collector electrode is connected with the end of Jc, emitter is connected with the N end of power supply input, the other end of Jc is connected with the A of power supply circuits point, and Dc2 also is connected in the two ends of Jc.The operation principle of this control unit is basic identical with Fig. 2, and the threshold voltage TH that just arranges is different with trigger voltage TR.
The sample circuit of the 4th K switch d state conversion shown in figure comprises the 9th unidirectional element Dd1, the 14 capacitor C d1, the 14 resistance R d1, the 15 resistance R d2, the 16 resistance R d3, after described Dd1, Rd1, Rd2, Rd3 connect mutually, an end is connected with the L end of power supply input, the other end is connected with the N end of power supply input, the end of Cd1 is connected with the negative pole of Dd1 and the tie point of Rd1, and the other end of Cd1 connects with the N end of power supply input.The drive signal circuit of the 4th K switch d state conversion shown in figure comprises the 4th integrated circuit die I Cd and the 15 capacitor C d2, the 17 resistance R d4, the power input of described ICd connects the A point of described power supply circuits, high-triggering end is connected with the tie point of Rd1, Rd2, low triggering end connects the center tap terminal of Rd3, output termination Rd4, control end connects the N end of power supply input by Cd2, common is connected with the N end of power supply input.The drive circuit of the 4th K switch d state conversion shown in figure and executive circuit comprise driving element the 4th transistor GBd, state conversion executive component the 4th relay J d, the tenth unidirectional element Dd2, the base stage of described GBd meets Rd4, collector electrode is connected with the end of Jd, emitter is connected with the N end of power supply input, the other end of Jd is connected with the A of power supply circuits point, and Dd2 also is connected in the two ends of Jd.The operation principle of this control unit is basic identical with Fig. 2, and the threshold voltage TH that just arranges is different with trigger voltage TR.
in the circuit of Fig. 1 to Fig. 4, the technical solution of the utility model, Current Control to the LED lamp system is divided into 4 shelves (can divide as required more shelves), be respectively input lower than two shelves of rated voltage and input two shelves higher than rated voltage, now illustrate with three different situations, the one, input voltage is 160V (lower than rated voltage), input voltage is lower than ICa, ICb, ICc, the threshold voltage TH of ICd, this moment according to the logical relation of integrated circuit (IC) chip as can be known, ICa, ICb, ICc, the ICd output is 1, relay J a, Jb, Jc, Jd is adhesive, capacity=the capacitor C of circuit capacitance+Ca+Cb+Cc+Cd.The 2nd, input voltage is 220V (rated voltage), and be set to lower than 220V (higher than 160V) due to the threshold voltage TH of ICc, ICd this moment, and output is 0, so relay J c, not adhesive of Jd.Because the threshold voltage TH of ICa, ICb is set to higher than 220V (lower than 250V), output is 1, so relay relay J a, Jb adhesive.Capacity=the capacitor C of circuit capacitance+Ca+Cb.The 3rd, input voltage be 250V (higher than rated voltage) this moment due to the input electricity all higher than the threshold voltage TH of ICa, ICb, ICc, ICd, so ICa, ICb, ICc, ICd output are 0, relay J a, Jb, Jc, not adhesives of Jd, the capacity=capacitor C of circuit capacitance.
When above-described embodiment, input voltage changed at 160V~250V, the rate of change of circuital current can reach ± and 5%, efficient can reach 95%
What above-mentioned the utility model was enumerated is only better embodiment of the present invention, and all equivalent technologies conversion of doing under operation principle of the present utility model and thinking all are considered as protection range of the present utility model.