Low-voltage and high-current synchronous rectified power
Technical field
The utility model relates to power switch power technique fields, is specifically related to a kind of low-voltage and high-current synchronous rectified power of powering for industrial production automatic control equipment.
Background technology
The Switching Power Supply being used in industrial process control system is at present a lot, although some are manufactured producer and have employed new technology in high power switching power supply, but consider the factor of power, components and parts select or separate piece too much, Switching Power Supply overall structure is so just made to be difficult to embody the advantage of new technology, be operated in its stability under high-power state, reliability is difficult to ensure, failure rate is high, particularly concerning the higher industrial equipment of automaticity, such Switching Power Supply is obviously difficult to the demand adapting to equipment.
In recent years along with the development of power technology, synchronous rectification is applied rapidly in the DC/DC converter of low-voltage, High-current output.The loss of DC/DC converter forms primarily of 3 parts: the loss of power switch pipe, the loss of high frequency transformer, the loss of output rectifying tube.When low-voltage, High-current output, the conduction voltage drop of rectifier diode is higher, and the loss of output rectifying tube is particularly outstanding.Fast recovery diode (FRD) or Ultrafast recovery diode (SRD) can reach 1.0 ~ 1.2V, even if adopt the Schottky diode (SBD) of low pressure drop, also can produce the pressure drop of about 0.6V, this just causes rectifier loss to increase, and power-efficient reduces.Illustrate, current notebook computer generally adopts the 3.3V even supply power voltage of 1.8V or 1.5V, and the electric current consumed can reach 20A.Now the rectifier loss of Ultrafast recovery diode is close to even exceeding 50% of output power of power supply.Even if employing Schottky diode, the loss on rectifying tube also can reach (18% ~ 40%) PO, accounts for more than 60% of power supply total losses.Therefore, traditional diode rectifier circuit cannot meet the needs realizing low-voltage, high-current switch high efficiency of power supply and small size, becomes the bottleneck that restriction DC/DC converter is raised the efficiency.
Utility model content
It is reasonable that technical problem to be solved in the utility model is to provide a kind of project organization, the low-voltage and high-current synchronous rectified power energy-efficient, output ripple coefficient is low, output voltage stabilization, safety and stability, reliability are high.
Technical problem to be solved in the utility model realizes by the following technical solutions:
A kind of low-voltage and high-current synchronous rectified power, is characterized in that: by power filter, overcurrent protection, single-phase bridge rectification filter circuit, Switching Power Supply control module, and circuit of synchronous rectification and decompression filter protective circuit are formed; Wherein power filter, overcurrent protection, single-phase bridge rectification filter circuit provide the power-frequency voltage of high order harmonic component of filtering, export a level and smooth direct current supply Switching Power Supply control module, through the circuit of synchronous rectification of low-voltage and high-current, control low internal resistance through IC, big current, low-voltage metal-oxide-semiconductor export zero crossing at transformer and carry out conducting effectively with turning off and control, and then realize synchronous rectification;
Described power filter, overcurrent protection, single-phase bridge rectification filter circuit are used for the electromagnetic interference of control inputs voltage and overcurrent protection, comprise Electromagnetic interference filter T1, cartridge fuse F1, the 5th diode D5, the 8th resistance R8 and bridge rectifier BT101, described cartridge fuse F1 is connected to Electromagnetic interference filter T1 input, act on overload protection, after the common mode that described Electromagnetic interference filter T1 produces input circuit, the decay of string mould electromagnetic interference height, provide input voltage to bridge rectifier BT101; Be connected to current suppressor RT between described Electromagnetic interference filter T1 and bridge rectifier BT101, restriction impulse current is to the harmful effect of bridge rectifier BT101; Described 5th diode D5 and the 8th resistance R8 forms power indicating circuit after connecting, described bridge rectifier BT101 is parallel with the tenth electric capacity C10, described bridge rectifier BT101 is to after the ac voltage rectifier of input, filtering is carried out by the tenth electric capacity C10, there is provided the direct current of an about 300V, supply switch power module circuit input end;
Described Switching Power Supply control module is made up of DC/DC power module U2 and switch transformer, and described switch transformer exports several groups of discontinuous output currents, for circuit of synchronous rectification;
Described circuit of synchronous rectification comprises two groups of transformers, first rectification IC integrated chip U1, 3rd rectification IC integrated chip U3, first diode D1), first electric capacity C1, second electric capacity C2, 3rd diode D3, 13 electric capacity C13, 15 electric capacity C15, first resistance R1, 5th resistance R5, first metal-oxide-semiconductor Q1, second metal-oxide-semiconductor Q2, 3rd resistance R3, 9th electric capacity C9, 7th resistance R7, 16 electric capacity C16, 3rd electric capacity C3, 5th electric capacity C5 and the second filter inductance L2, two groups of transformers assist winding respectively through the first diode D1, first electric capacity C1, second electric capacity C2, 3rd diode D3, 13 electric capacity C13, 15 electric capacity C15 gives the first rectification IC integrated chip U1, 3rd rectification IC integrated chip U3 powers, as the first rectification IC integrated chip U1, 3rd rectification IC integrated chip U3 the 1st pin is through the first resistance R1, 5th resistance R5 detects negative pressure, first rectification IC integrated chip U1, 3rd rectification IC integrated chip U3 drives pin 4, export control first metal-oxide-semiconductor Q1, the conducting of the second metal-oxide-semiconductor Q2 and closedown, and then form synchronous rectification control, described 3rd resistance R3, the 9th electric capacity C9 and the 7th resistance R7, the 16 electric capacity C16 are respectively peak absorbing circuit, for the protection of the first metal-oxide-semiconductor Q1 and the second metal-oxide-semiconductor Q2, so just obtain the DC output power of one group of low-voltage and high-current, then be connected to o-volt protection freewheeling circuit through the 3rd electric capacity C3, the 5th electric capacity C5 and the second filter inductance L2,
Described decompression filter protective circuit comprises the second diode D2, 4th resistance R4, relay K 1 and the 7th diode D7, described second diode D2 positive pole is connected to Switching Power Supply output cathode V+, second diode D2 negative pole is connected to Switching Power Supply output negative pole V-after connecting with the 4th resistance R4, form Switching Power Supply and export indicating circuit, described relay K 1 is connected to Switching Power Supply and is just exporting, negative pole two ends, described 7th diode D7 positive pole connects Switching Power Supply output negative pole, 7th diode D7 negative pole connects the output cathode of Switching Power Supply, described relay K 1 and the 7th diode D7 form o-volt protection freewheeling circuit, when Switching Power Supply turns off decompression, freewheeling circuit just can discharge in coil and store poly-energy, prevent the too high damage Switching Power Supply of induced voltage.
Excellent on state characteristic because of metal-oxide-semiconductor outclass the on state characteristic of diode, thus realize the outstanding output characteristic of low-voltage and high-current synchronous rectified power: low heating, low consumption, energy-efficient characteristic, especially under being used in the occasion of low-voltage and high-current power supply output rectification, efficient energy-saving successful.Itself technology has that certain advance, structure are simple, cost is lower; stable output; heat dissipation capacity is little; promote very large to power supply conversion efficiency; again by o-volt protection freewheeling circuit 4; this just makes us obtain one group of comparatively ideal high-efficiency and energy-saving type power stage, realizes the object of utility model, for industrial stokehold provides a Switching Power Supply of a kind of rational in infrastructure, stable output, the utility model that energy-efficient, security reliability is high.
The beneficial effects of the utility model are:
1) circuit design is novel, succinct, compact, and comprehensive function is powerful.
2) select on state characteristic to outclass the metal-oxide-semiconductor IRFB3207 of diode, energy-efficient, caloric value is little.
3) design and selected the integrated chip such as advanced DC/DC, synchronous rectification ICTEA1791T, using circuit components significantly to reduce, feasibility and stability improve.
4) can realize stable relatively high power to export, actual test output current can reach 25A/7.25V.
5) electric power output voltage 7.25V, output current 25A, primary side conventional schottky 30CPQ100 rectification is at 25 DEG C, and forward voltage drop is 1.0V, and actual measurement metal-oxide-semiconductor IRFB3207 synchronous rectification, forward voltage drop is 25A*0.0033 Europe=0.0825V.Only have 1/10th of Schottky diode pressure drop less than, energy-efficient successful.
Accompanying drawing explanation
Fig. 1 is the utility model circuit theory diagrams.
Embodiment
The technological means realized to make the utility model, creation characteristic, reaching object and effect is easy to understand, below in conjunction with concrete diagram, setting forth the utility model further.
See Fig. 1:
A kind of low-voltage and high-current synchronous rectified power, use NXP company synchronous rectification ICTEA1791T control metal-oxide-semiconductor IRFB3207 conducting and shutoff to carry out synchronous rectification output, it is applicable to the secondary output synchronous rectification of switch transformer of discontinuous transmission mode and anti exciting converter and so on; It is characterized in that: by power filter, overcurrent protection, single-phase bridge rectification filter circuit, Switching Power Supply control module, circuit of synchronous rectification and decompression filter protective circuit are formed; Wherein power filter, overcurrent protection, single-phase bridge rectification filter circuit provide the power-frequency voltage of high order harmonic component of filtering, export a level and smooth direct current supply Switching Power Supply control module, through the circuit of synchronous rectification of low-voltage and high-current, control low internal resistance through IC, big current, low-voltage metal-oxide-semiconductor export zero crossing at transformer and carry out conducting effectively with turning off and control, and then realize synchronous rectification;
Excellent on state characteristic because of metal-oxide-semiconductor outclass the on state characteristic of diode, thus realize the outstanding output characteristic of low-voltage and high-current synchronous rectified power: low heating, low consumption, energy-efficient characteristic, especially under being used in the occasion of low-voltage and high-current power supply output rectification, efficient energy-saving successful.Itself technology has that certain advance, structure are simple, cost is lower; stable output; heat dissipation capacity is little; promote very large to power supply conversion efficiency; again by o-volt protection freewheeling circuit 4; this just makes us obtain one group of comparatively ideal high-efficiency and energy-saving type power stage, realizes the object of utility model, for industrial stokehold provides a Switching Power Supply of a kind of rational in infrastructure, stable output, the utility model that energy-efficient, security reliability is high.
Described power filter, overcurrent protection, single-phase bridge rectification filter circuit are used for the electromagnetic interference of control inputs voltage and overcurrent protection, comprise Electromagnetic interference filter T1, cartridge fuse F1, light-emitting diode D5, resistor R8 and bridge rectifier BT101, described cartridge fuse F1 is connected to Electromagnetic interference filter T1 input, act on overload protection, after the common mode that described Electromagnetic interference filter T1 produces input circuit, the decay of string mould electromagnetic interference height, provide input voltage to bridge rectifier BT101; Be connected to current suppressor RT between described Electromagnetic interference filter T1 and bridge rectifier BT101, restriction impulse current is to the harmful effect of bridge rectifier BT101; Described light-emitting diode D5 and resistor R8 forms power indicating circuit after connecting, described bridge rectifier BT101 is parallel with electrochemical capacitor C10, described bridge rectifier BT101 is to after the ac voltage rectifier of input, filtering is carried out by electrochemical capacitor C10, there is provided the direct current of an about 300V, supply switch power module circuit input end;
Described Switching Power Supply control module is made up of DC/DC power module U2 and switch transformer, and described switch transformer exports several groups of discontinuous output currents, for circuit of synchronous rectification;
Described circuit of synchronous rectification comprises two groups of transformers, rectification ICTEA1791T integrated chip U1, U3, diode D1, electric capacity C1, electric capacity C2, diode D3, electric capacity C13, electric capacity C15, resistance R1, resistance R5, metal-oxide-semiconductor Q1, MOSQ2, resistance R3, electric capacity C9, resistance R7, electric capacity C16, electric capacity C3, electric capacity C5 and filter inductance L2, two groups of transformers assist winding respectively through diode D1, electric capacity C1, electric capacity C2, diode D3, electric capacity C13, electric capacity C15 rectifying and wave-filtering is to U1, U3 powers, work as U1, U3 the 1st pin (SRSENSE) is through resistance R1, resistance R5 detects negative pressure, U1, U3 drives pin 4, export and control metal-oxide-semiconductor Q1, the conducting of Q2 and closedown, and then form synchronous rectification control, resistance R3, electric capacity C9 and resistance R7, electric capacity C16 is respectively peak absorbing circuit, for the protection of metal-oxide-semiconductor, so just obtain the DC output power of one group of low-voltage and high-current, again through filter capacitor C3, electric capacity C5, filter inductance L2 is connected to o-volt protection freewheeling circuit,
Described decompression filter protective circuit comprises light-emitting diode D2, resistance R4, relay K 1 and diode D7, described light-emitting diode D2 positive pole is connected to Switching Power Supply output cathode V+, negative pole is connected to Switching Power Supply output negative pole V-after connecting with resistance R4, form Switching Power Supply and export indicating circuit, described relay K 1 is connected to Switching Power Supply and is just exporting, negative pole two ends, described diode D7 positive pole connects Switching Power Supply output negative pole, its negative pole connects the output cathode of Switching Power Supply, described relay K 1 and diode D7 form o-volt protection freewheeling circuit, when Switching Power Supply turns off decompression, freewheeling circuit just can discharge in coil and store poly-energy, prevent the too high damage Switching Power Supply of induced voltage.
Important technological parameters:
1, power supply input: 90 ~ 260V50Hz
2, output voltage: 7.2V
3, output current: 25A
4, ripple voltage: <25mV
Operating ambient temperature :-10 ~ 70 DEG C
More than show and describe general principle of the present utility model and principal character and advantage of the present utility model.The technical staff of the industry should understand; the utility model is not restricted to the described embodiments; what describe in above-described embodiment and specification just illustrates principle of the present utility model; under the prerequisite not departing from the utility model spirit and scope; the utility model also has various changes and modifications, and these changes and improvements all fall within the scope of claimed the utility model.The claimed scope of the utility model is defined by appending claims and equivalent thereof.