CN207572318U - A kind of driving device of relay - Google Patents

Abstract

The utility model is related to control field more particularly to a kind of driving devices of relay.To reduce Wen Sheng during relay work, so that relay can be operated under higher environment temperature.A kind of driving device of relay provided by the utility model includes：Bleeder circuit, first switch circuit and control circuit apply driving voltage when relay starts to relay coil, and the voltage at coil both ends is down to holding voltage after relay steady operation, so as to reduce Wen Sheng during relay working condition.

Description

A kind of driving device of relay

Technical field

The utility model is related to control field more particularly to a kind of driving devices of relay.

Background technology

Relay is as switch element, in various control circuits, in order to meet making for control relay With environment temperature, for the use environment temperature for the control circuit applied, there has also been certain restrictions.Such as the drive of servo motor In dynamic device, in order to meet the use environment temperature of control relay, driving the servo amplifier of servo motor generally has The limitation of use environment temperature, the height of this use environment temperature depend on the relay of different size, and common such as 55 ℃.But interfering with each other due to servo amplifier heat-generating components inside, a certain local environment temperature could possibly be higher than using ring Border temperature, such as reach 65 DEG C or higher.In this way when relay is placed on this high-temperature area or neighbouring high-temperature area, by It is more than limitation in environment temperature, then causes relay is controlled to can not work normally, and then influence the safety of servo amplifier.

Therefore the use environment temperature of control relay how is improved, so that the control circuit energy using relay It is enough to be worked normally under more high environment temperature, to improve the safety of entire control circuit, it is one and needed to be considered important asks Topic.

Utility model content

The utility model provides a kind of driving device of relay, to reduce Wen Sheng during relay work, so as to It can be operated under higher environment temperature.

On the one hand the utility model provides a kind of driving device of relay, including：Bleeder circuit, first switch circuit and Control circuit, wherein：The bleeder circuit is connected to the first end of the coil of the relay and the driving electricity of the relay Between first terminals in source, the second end of the coil is connect with the second terminals of the driving power, and the first ratio More than or equal to the second ratio, first ratio is the resistance value of the coil and the resistance value of the coil and the bleeder circuit The sum of resistance value ratio, second ratio is the minimum hold-in voltage for the working condition for keeping the relay and driving electricity The ratio of pressure；The first switch be electrically connected to the first end of the coil and the driving power the first terminals it Between, the control circuit responds the drive signal of the relay and the first switch circuit is controlled to connect, and it is described after Electric appliance controls the first switch circuit to disconnect after being closed.

Relay coil is given to apply driving electricity in relay controller provided by the utility model, during starting relay Pressure, and the voltage at coil both ends is down to holding voltage after relay steady operation, since relay starts to steady operation Time needed for state is very short, starts influence very little of the voltage to relay Wen Sheng, relay is under continuous firing state, coil Both ends only apply holding voltage, and voltage is kept, which relatively to start voltage, can reduce very much, so as to reduce relay working condition When Wen Sheng.

The another aspect of the utility model also provides a kind of driving device, further comprises second switch circuit, with The bleeder circuit branch circuit to be formed of connecting is connected to the first end of the coil and the first wiring of the driving power Between end, and the control circuit controls the second switch circuit to connect before the first switch circuit is controlled to disconnect, Either the control circuit controlled while the first switch circuit is controlled to disconnect the second switch circuit connect or The control circuit controls the second switch circuit to connect while the first switch circuit is controlled to connect.

Due to increasing second switch circuit, so as to when needing to close relay, using second switch circuit to discharge Relay.

In a specific embodiment, in driving device provided by the utility model, the control circuit can include：The One photosignal coupler, the second photosignal coupler and delay circuit, wherein：

The drive signal controls the first photosignal coupler and each self-conductance of the second photosignal coupler Logical, the first photosignal coupler controls the first switch circuit connection, second photosignal when switched on Coupler controls when switched on the second switch circuit to connect, and the delay circuit controls described the after duration is set Two photosignal couplers turn off.

Further, the delay circuit includes NOT gate and door, resistance, capacitance, diode and third switching circuit, wherein： The drive signal is input into the first input end with door by the NOT gate, and the drive signal is also inputted to institute The cathode of diode is stated, the anode of the diode is connect by the resistance with described with the second input terminal of door, the electricity Appearance is connected between second input terminal and ground terminal, and second input terminal is also connect by the resistance with high level, The output terminal with door controls the third switching circuit to connect, and the third switching circuit controls described the when being switched on Two photosignal couplers are connected.

As a specific example, the second ratio is more than or equal to 0.3 and less than or equal to 0.6.

When driving relay according to this driving device as a result, you can by changing the voltage at coil both ends, reduce coil temperature It rises so that relay can be designed to be worked normally in higher environment temperature, to solve due to a certain in amplifier circuit board Regional environment temperature excessively high the problem of causing this region that can not put relay.Can also while solving the above problem, Due in coil having sealed in bleeder circuit during normal work, so as to reduce the electric current for flowing through coil, due to electric current stream on coil Waste heat amount that is logical and generating also is reduced therewith.In this way, it also plays energy conservation and efficiently uses the effect of electric energy.

Description of the drawings

Fig. 1 is the structure diagram of the relay controller of embodiment one provided by the utility model；

Fig. 2 is a kind of concrete structure schematic diagram of driving power in the embodiment one that the utility model embodiment provides；

Fig. 3 is another concrete structure schematic diagram of driving power in the embodiment one that the utility model embodiment provides；

Fig. 4 is the structure diagram of the relay controller of embodiment two provided by the utility model；

Fig. 5 is a kind of concrete structure schematic diagram of relay controller provided by the utility model；

Fig. 6 is the control sequential figure of specific example shown in Fig. 5；

Fig. 7 is the electrical block diagram of a specific example of relay controller provided by the utility model.

Specific embodiment

Wen Sheng when relay works is influenced by two factors, and one is the Wen Sheng of itself, and one is environment temperature, And the principal element for influencing relay itself Wen Sheng is the operating voltage or operating current of relay coil.With relay line The reduction of operating voltage is enclosed, the Wen Shenghui of relay itself declines therewith.After being closed in view of relay, its work can be kept The voltage of state is low compared to voltage is started, therefore can reduce relay after relay closes and is combined into steady-working state The operating voltage of device is to keep its working condition, so as to reduce the Wen Sheng of itself under relay working condition so that relay Device can work in higher ambient temperature stable.Based on this, in relay controller provided by the utility model, relay Apply driving voltage to relay coil when device starts, and the voltage at coil both ends is down to holding after relay steady operation Voltage, since relay starts to, time needed for steady-working state is very short, starts influence of the voltage to relay Wen Sheng very Small, for relay under continuous firing state, coil both ends only apply holding voltage, and voltage is kept, which relatively to start voltage, to be reduced Very much, so as to reduce Wen Sheng during relay working condition.The startup voltage of relay is generally the amount voltage of relay, And it usually can be some value between the 30%~60% of rated voltage to keep voltage, i.e.,.

It is described in detail below with specific embodiment and with reference to attached drawing.

As shown in Figure 1, one embodiment of the driving device of relay that the utility model is provided based on above-mentioned analysis, The driving device of the relay specifically includes：Control circuit 11, bleeder circuit 12 and switching circuit 13,141 He of the first terminals Second terminals 142 are two terminals of relay driving power supply.In this embodiment, bleeder circuit 12 and switching circuit 13 is in parallel, and parallel circuit is connected between one end of the coil 10 of relay and the first terminals of driving power 141, coil 10 The other end connects the second terminals of driving power 142 of relay.I.e. bleeder circuit 12 is connected to the one of the coil 10 of relay Between end and the first terminals of driving power 141, switching circuit 13 is also connected to one end of the coil 10 of relay and driving electricity Between the first terminals of source 141, control signal that control circuit 11 is sended over according to system controls connecing for switching circuit 13 Logical or disconnection, when switching circuit 13 is connected, two terminal shortcircuit of bleeder circuit, driving voltage are applied directly to by switching circuit 13 The both ends of coil 10, coil 10 must be electric, and relay is closed, and when switching circuit 13 disconnects, driving voltage is applied to 10 He of coil The branch road that bleeder circuit 12 is formed, since the partial pressure of bleeder circuit 12 acts on, the voltage applied on coil 10 is compared to driving electricity Pressure then decreases.

The course of work of relay controller shown in FIG. 1 is：When needing starting relay, system is to control circuit 11 Send enabling signal, control circuit 11 respond relay enabling signal, control switching circuit 13 connect, driving voltage be added to after On electric apparatus coil 10, coil 10 obtains electric, relay closure, and the working condition of stabilization, control circuit are entered after setting duration 11 can control switching circuit 13 to disconnect after duration is set, and after control switching circuit 13 disconnects, driving voltage is applied to coil 10 and the branch road that is formed of bleeder circuit 12, since the partial pressure of bleeder circuit 12 acts on, so as to make the work at 10 both ends of coil electric Pressure is less than driving voltage.In running order for guard relay, the voltage got on coil 10 is had to be larger than equal to protecting The minimum voltage of relay working condition is held, for this purpose, the resistance value of coil 10 and the resistance value of bleeder circuit 12 need to meet as follows Formula 1：

v_x/(v_x+v_f)≥v_min/v_q... .. formula 1

Wherein, v_xFor the partial pressure value on coil 10, v_fFor the partial pressure value on bleeder circuit, v_minFor guard relay work shape The minimum voltage of state, v_qRated voltage for the driving voltage of relay, usually relay.Formula 1 is：The resistance value of coil With the ratio of the sum of the resistance value of itself and bleeder circuit, minimum voltage and relay more than or equal to guard relay working condition drive The ratio of dynamic voltage, the size of this ratio can be more than or equal to 0.3 and less than or equal to 0.6, as ensure the steady of relay Determine working condition, keep voltage that can at most be reduced to the 30% of rated voltage, to drop low-temperature-rise as far as possible, keep voltage minimum Also the 60% of rated voltage is reduced to.The resistance value of coil mentioned here refers to the equivalent resistance measured from coil both ends Resistance value, the resistance value of similary bleeder circuit are the resistance values for the equivalent resistance that circuit both ends measure.It should be noted that for relay From the setting duration being closed into steady-working state, those skilled in the art can rule of thumb set completely, such as Relay, which was closed on the required time, increases certain remaining to ensure the reliability of relay work, lifts a specific example, Such as the relay closing time of certain model is 120ms, then setting time can be set as 120ms or slightly larger than 120ms i.e. It can.

Driving device according to Fig. 1, the holding applied by reducing relay steady-working state lower coil both ends Voltage can reduce the Wen Sheng of coil.According to test, keep voltage that can be reduced to the 30%~60% of rated voltage, with after Electric apparatus coil continuous firing is compared under rated voltage, reduces the Wen Sheng of relay coil itself, so as to improve relay To the adaptability of environment temperature, so that relay can be operated under higher environment temperature.Such as specifically show at one In example, the environment temperature highest that can be used when relay is applied in rated voltage only has 55 DEG C, but applied after relay closure When adding 50% rated voltage as voltage is kept, coil itself Wen Sheng of relay will be no more than 45 DEG C, accordingly even when should be after Electrical work is under 85 DEG C of environment temperature, and the whole temperature of relay rises and can also be maintained in safe range, so as to ensure that Relay can be operated under environment at higher temperature.

As shown in fig.1, after switching circuit 13 is disconnected, the holding voltage of partial pressure gained on coil 10 can be by dividing The resistance value of volt circuit 12 is adjusted, and is generally selected between the 30%~60% of rated voltage, is kept voltage more high, is helped Stable working condition is kept in relay, but the reduction amplitude of itself Wen Sheng is then smaller, so in satisfaction needs environment temperature Under the premise of degree, keep voltage that can select as possible higher.Such as environment temperature is at 70 degree, keeps voltage for example can be with 55% for rated voltage.The relationship between the size of voltage and use environment temperature is kept, can be surveyed by appropriate experiment It is fixed.

Fig. 2 and Fig. 3 gives the specific composition mode of two kinds of driving voltages, the first terminals 141 and the second terminals 142 The upper difference in voltage applied respectively is equal to the driving voltage of relay, such as shown in Fig. 2, the first terminals 141 can connect Ground terminal is connected to, the second terminals 142 can directly apply rated voltage.Again for example shown in Fig. 3, the first terminals 141 and Two terminals 142 can apply 50% positive rated voltage, i.e. half respectively as the positive and negative anodes of driving power, one v_q, another applies 50% rated voltage of negative sense.

As shown in figure 4, for second embodiment provided by the utility model, on the basis of embodiment one, relay drives Dynamic device increases a switching circuit, for controlling the break-make of bleeder circuit place branch, specifically, the driving device packet It includes：Control circuit 41 and bleeder circuit 42 and first switch circuit 431 and second switch circuit 432.Wherein：First switch One end ground connection of circuit 431, the other end connect one end of coil 40, the driving power of the other end connection relay of coil 40 Second terminals 442.The branch circuit that second switch circuit 432 is formed after connecting with bleeder circuit 42, one end are connected to coil 40 one end, the other end connect the first terminals 441 of driving power.

In driving device shown in Fig. 4, when first switch circuit 431 is connected, driving voltage passes through first switch circuit 431 It is applied directly on coil 40, coil 40 obtains electric, relay closure.When first switch circuit 431 disconnects and second switch circuit During 432 connection, driving voltage is divided by coil 40 and bleeder circuit 42, and the voltage being applied on coil 40 is minimized.When When one switching circuit 431 and second switch circuit 432 disconnect, 40 dead electricity of coil, relay is released and is stopped.

In the present embodiment, control circuit 41 controls first switch circuit 231 to be closed according to relay enabling signal, and Control first switch circuit 231 disconnects after relay enters steady-working state, before first switch circuit 231 disconnects or disconnected It opens simultaneously, second switch circuit 232 needs in an ON state, and for requirement as satisfaction, control circuit 41 can be according to startup Signal controls first switch circuit 231 to be connected with second switch circuit 232 simultaneously, and by first switch circuit after duration is set 231 disconnect, and second switch circuit 232 can also be controlled to connect before the disconnection of first switch circuit 231 or while disconnection, As long as meet before first switch circuit 231 disconnects or disconnect, second switch circuit 232 is in an ON state It can.

It is compared with embodiment one, second switch circuit 232 is increased in second embodiment, effect can control partial pressure Branch where circuit switches on and off, so as to which when needing to close relay, second switch electricity is disconnected using control circuit 21 Road 232 is with release relay.

In driving device shown in embodiment one and embodiment two, there are many available switching circuit, such as analog line driver Part etc., the composition of bleeder circuit is also very more, can usually use a resistance or use multiple series-parallel resistance structures Into control circuit can be realized using programmable controller, can also be realized using hardware circuit, specifically be shown with one again below Example is described in detail.

As shown in figure 5, a specific example for driving device shown in Fig. 4, first switch circuit and second switch circuit It is specific to select power drive device MOS-FET₁(Metal-Oxide-Semiconductor Field-Effect Transistor, MOSFET, Metal-Oxide Semiconductor field-effect transistor, abbreviation metal-oxide half field effect transistor) and MOS- FET₂, bleeder circuit is specially a divider resistance R.One end connection rated voltage direct current 24V of relay coil, the other end lead to Overpower driving element MOS-FET₁Ground connection, while pass through divider resistance R and MOS-FET₂The grounding of formation, MOS-FET₁ And MOS-FET₂Conduction mode be set as low level conducting.Wherein MOS-FET₁The divider resistance R of series connection plays the work of partial pressure With.MOS-FET₁, MOS-FET₂Pass through the RLYON of direct current 12V respectively₁And RLYON *₂* signal control turn-on and turn-off, RLYON₁* And RLYON₂* signal comes from control circuit.

In the present embodiment, the driving device relay to be driven has following characteristic, required driving when coil is closed Voltage is 24V, and low hold voltage can be dropped after relay is closed completely, and keeps voltage that can be reduced to 24V rated voltages 30%~60% between a voltage value, apply keep voltage in the state of, coil temperature rise is compared with the feelings of 24V rated voltages It decreases under condition, the requirement that relay can work in an environment of high temperature can be realized by such method.For example, point When the resistance value of piezoresistance R and equal coil, holding voltage can be made to be down to the 50% of rated voltage, i.e. 12V, greatly reduce line The Wen Sheng of circle.

As shown in fig. 6, the control sequential figure for driving device shown in fig. 5, is divided into following four rank according to the course of work Section：

Ⅰ：Before relay starts

RLYON₁And RLYON *₂* it is high level, MOS-FET₁And MOS-FET₂It is not turned on, relay coil, which is in, to be lost Electricity condition；

Ⅱ：Starting relay

When needing starting relay, drive signal drives the enabling signal of photosignal coupler conducting to give simultaneously To RLYON₁And RLYON *₂*, RLYON₁And RLYON *₂* low level is become from high level, at this time MOS-FET₁And MOS-FET₂ It simultaneously turns on, MOS-FET₂By bleeder circuit R and MOS-FET₁The branch, short-circuit of formation, passes through MOS-FET at this time₂, relay line Circle both ends obtain it is electric, the voltage being applied in be 24V, relay be closed；

Ⅲ：Operating voltage is reduced to holding voltage

By setting duration, relay enters steady-working state after being closed completely, then by controlling RLYON₂* signal Become high level, by MOS-FET₂Shutdown.MOS-FET₂After shutdown, relay coil passes through divider resistance R and MOS-FET₁It leads Logical, due to the effect of divider resistance, the voltage drop at coil both ends is down to 12V, the only half of 24V.In this way when the normal work of system When making, the holding voltage at coil both ends is 12V, you can meets relay and works normally under high temperature environment；

Ⅳ：Relay is stopped

When relay is needed to be stopped, the signal of RLYON1* is controlled to become high level, by MOS-FET₁Shutdown, after Electric apparatus coil is in open-circuit condition, and coil losing electricity is stopped with release relay, relay.

From fig. 6, it can be seen that in this specific example, coil both ends are applied with 24V in the stage II and start voltage, in the stage The holding voltage applied in III working time is only 12V.In this specific example, the time usual 120ms in stage II, It is very of short duration compared to normal working hours, influence of this period to coil temperature rise can be ignored.

As shown in fig. 7, a specific example for a kind of driving device provided by the utility model, in the specific example, First switch circuit and second switch circuit specifically select the conducting of power drive device Q301 and Q303, Q301 and Q303 to set It is connected for high level, bleeder circuit is formed by R301~R306 connection in series-parallel, and resistance value and coil K resistance values are equal.When Q301 is connected When, coil K is connected with the circuit that bleeder circuit forms, and when Q303 is connected, coil K both ends directly apply 24V driving voltages.

Photosignal coupler PC301 is the driving circuit of Q301, buffer U301, U302, Q302, PC302, Yi Ji electricity R311, capacitance C312 and diode D313 are hindered, has collectively constituted the driving circuit of Q303, wherein, buffer U301 is non-for one Door, U302 be one and door, wherein：Drive signal controls the conducting of Q301 by PC301；Meanwhile drive signal passes through U301 The first input end of U302 is inputted, and inputs the cathode of D313, the anode of D313 is connected to the second of U302 by resistance R311 Input terminal, capacitance C312 are connected between the second input terminal of U302 and ground terminal, and the second input terminal of U302 also passes through resistance R311 connection high level, the turn-on and turn-off of the output terminal control Q302 of U302, Q302 further control conducting and the pass of PC302 Disconnected, PC302 controls the second field-effect transistor conducting Q302 conductings when being connected.Resistance R311, capacitance C312 and diode The charge-discharge circuit that D313 is formed constitutes delay circuit, can be with time delayed turn-off Q302, by adjusting resistance R311 and capacitance The parameter of C312 can be with regulating relay from the setting duration started to needed for steady operation.

The course of work of driving device shown in definition graph 7 stage by stage below：

Ⅰ：Before starting relay

RLYON* is high level, photosignal coupler PC301 shutdowns, then Q301 shutdowns, coil K and bleeder circuit composition Circuit for off state, coil K can not be obtained electric by Q301；

RLYON* is high level, buffer U301 output low levels, buffer U302 be with door, No. 1 of buffer U302 Pin is low level, and No. 2 pins of U302 are high level, then U302 No. 4 output pin is low level state, then Q302 is in Off state, RLYON** are high level, and by state at photosignal coupler PC302, then Q303 is off state, line The circuit that circle K passes through Q303 is also what is disconnected, and coil K can not be obtained electric by Q303.

Ⅱ：Relay startup stage

When system needs relay to work, sending filter enabling signal, RLYON* becomes low level from high level, then PC301 is connected, and then Q301 is connected.

Simultaneously as RLYON* becomes low level from high level, buffer U301 output pins become high level, buffer U302 is is high level with No. 1 pin of door, buffer U302, and No. 2 pins of U302 are high level, then U302 No. 4 export Pin transitions are high level, and Q302 is connected, and RLYON** signals switch to low level, and photosignal coupler PC302 is connected, then Q303 is connected.

As it can be seen that two accesses of connection relay coil K all turn on, access 1 for relay K- bleeder circuits R306~ R311-Q301, access 2 are relay K-Q303.Since access 2 is by 1 short circuit of access, relay coil voltage K is applied directly The voltage of 24V reaches the driving voltage of relay, and relay starts at this time, starts to work.

Ⅲ：By setting duration, relay enters steady-working state, and coil K both ends are applied in the holding voltage of 12V

After RLYON* becomes low level, C312 begins through R311 and D313 electric discharges, after the electric discharge of about 120ms, C312 electricity The threshold voltage that pressure drop is inputted as low as buffer U302 low levels, No. 2 pins of U302 become low level, buffer from high level No. 4 output pins of U302 become high level, then Q302 ends.Signal RLYON** becomes high level, light while Q302 ends Electric signal coupler PC302 is turned off, and Q303 is also turned off immediately, the access shutdown of coil K-Q303.And Q301 is still in conducting shape State, coil K are obtained by the access of bleeder circuit R301~R306 and are kept voltage, since bleeder circuit and coil K are connected, and point It is identical that volt circuit resistance value is designed as coil K resistance values, so relay coil both end voltage is 12V.Then following system is normal In work, the voltage at coil K both ends is always to keep voltage 12V.

It is closed into from relay into the 120ms durations needed for steady operation, it can be by selecting resistance R311, capacitance The parameter of C312 and diode D313 are set, and by adjusting the parameter of these three elements, it is possible to be adjusted it and be formed Charge-discharge circuit the charge and discharge time, so as to adjust relay from the time started into steady-working state.

Ⅳ：Relay is stopped

When relay is needed to be stopped, sending filter shutdown signal, RLYON* becomes high level from low level.This When everywhere state turn again to the later state of system electrification, relay coil K is via bleeder circuit R306~R311 and Q301 Access become turning off from being connected, coil K dead electricity, relay is released and is stopped.

The numerical value such as 24V, 12V and 120ms described in above-described embodiment are only a specific examples, driving voltage and are set Timing is long to be formed according to different application environments and circuit and is varied from, and those skilled in the art can be as the case may be It determines.

When driving relay according to this driving device as a result, you can by changing the voltage at coil both ends, reduce coil temperature It rises so that relay can be designed to be worked normally in higher environment temperature.To solve due to a certain in amplifier circuit board Regional environment temperature excessively high the problem of causing this region that can not put relay.While solving the above problem, due to just Bleeder circuit often has been sealed in coil during work, so flowing through the electric current of coil also reduces, has been produced on coil due to current flowing Raw waste heat amount is also reduced therewith.In this way, also play energy conservation and the effect efficiently used.

Obviously, those skilled in the art can carry out the utility model various modification and variations without departing from this practicality Novel spirit and scope.If in this way, these modifications and variations of the present invention belong to the utility model claims and Within the scope of its equivalent technologies, then the utility model is also intended to include these modifications and variations.

Claims (8)

1. a kind of driving device of relay, which is characterized in that including：Bleeder circuit, first switch circuit and control circuit, In：

The bleeder circuit is connected to the first end of the coil of the relay and the first of the driving power of the relay and connects Between line end, the second end of the coil is connect with the second terminals of the driving power, and the first ratio is more than or equal to the Two ratios, first ratio are the resistance value of the coil and the sum of the resistance value of the coil and the resistance value of the bleeder circuit Ratio, second ratio is the minimum hold-in voltage for the working condition for keeping the relay and the driving of the relay The ratio of voltage；

The first switch is electrically connected between the first end of the coil and the first terminals of the driving power, described Control circuit responds the drive signal of the relay and the first switch circuit is controlled to connect, and is closed in the relay The first switch circuit is controlled to disconnect later.

2. driving device as described in claim 1, which is characterized in that second switch circuit is further included, with the partial pressure electricity The road branch circuit to be formed of connecting is connected between the first end of the coil and the first terminals of the driving power, and institute It states control circuit and the second switch circuit connection or the control is controlled before the first switch circuit is controlled to disconnect Circuit controls the second switch circuit to connect while the first switch circuit is controlled to disconnect.

3. driving device as described in claim 1, which is characterized in that second switch circuit is further included, with the partial pressure electricity The road branch circuit to be formed of connecting is connected between the first end of the coil and the first terminals of the driving power, and institute Stating while control circuit controls the first switch circuit to connect controls the second switch circuit to connect.

4. driving device as claimed in claim 3, which is characterized in that the control circuit includes：First photosignal couples Device, the second photosignal coupler and delay circuit, wherein：

The drive signal controls the first photosignal coupler and the second photosignal coupler to be respectively connected, institute Stating the first photosignal coupler controls when switched on the first switch circuit to connect, the second photosignal coupler The second switch circuit is controlled when switched on to connect, the delay circuit controls second photoelectricity after duration is set Signal coupler turns off.

5. driving device as claimed in claim 4, which is characterized in that the delay circuit includes NOT gate and door, resistance, electricity Appearance, diode and third switching circuit, wherein：

The drive signal is input into the first input end with door by the NOT gate, and the drive signal is also input into To the cathode of the diode, the anode of the diode is connect by the resistance with described with the second input terminal of door, institute Capacitance connection is stated between second input terminal and ground terminal, second input terminal is also connected by the resistance and high level It connects, the output terminal with door controls the third switching circuit to connect, and the third switching circuit controls institute when being switched on State the conducting of the second photosignal coupler.

6. driving device as claimed in claim 5, which is characterized in that the first switch circuit, second switch circuit and Three switching circuits are respectively field-effect transistor.

7. the driving device as described in claim 1~6 is any, which is characterized in that the bleeder circuit is resistance, and described the Two ratios are more than or equal to 0.3 and less than or equal to 0.6.

8. the driving device as described in claim 1~6 is any, which is characterized in that the bleeder circuit is by multiple resistance groups Into series-parallel circuit, and second ratio is more than or equal to 0.3 and less than or equal to 0.6.