CN211880148U

CN211880148U - Power control system for charging pile

Info

Publication number: CN211880148U
Application number: CN202020691507.7U
Authority: CN
Inventors: 张健华; 卜争龙
Original assignee: Enyida Power Technology Suzhou Co ltd
Current assignee: Enyida Power Technology Suzhou Co ltd
Priority date: 2020-04-29
Filing date: 2020-04-29
Publication date: 2020-11-06
Anticipated expiration: 2030-04-29

Abstract

The utility model discloses a power control system for filling electric pile, include: the power supply comprises an input unit, a power conversion unit, an output unit, a current setting unit, an oscillation control unit, a main control unit and a protection unit, wherein the input unit comprises an input interface, an EMI (electro-magnetic interference) filter circuit and a rectification filter circuit which are sequentially connected, and the rectification filter circuit is connected with the power conversion unit; the power conversion unit comprises a first conversion circuit and a second conversion circuit, wherein the first conversion circuit and the second conversion circuit are respectively in inductive connection with the output unit and the oscillation control unit through transformers; the current setting unit is respectively connected with the output unit and the main control unit; the protection unit comprises an overvoltage protection unit, an overcurrent protection unit, a first over-temperature protection unit, a second over-temperature protection unit and a communication connector. The utility model discloses have excessive pressure, overflow, excess temperature protect function, protection power module that can be better.

Description

Power control system for charging pile

Technical Field

The utility model relates to a fill electric pile technical field, specifically relate to a power control system for filling electric pile.

Background

The electric automobile is a vehicle which takes a vehicle-mounted power supply as power and drives wheels to run by using a motor, and meets various requirements of road traffic and safety regulations. The composition comprises: an electric drive and control system, a mechanical system such as a drive transmission, a working device for performing a predetermined task, and the like. The automobile has a small influence on the environment, so that the prospect is widely seen, but the current technology is not mature. With the development of electric automobile technology, especially the increasing of the national atmospheric pollution control, the electric automobile as one of the best substitute products of the traditional power automobile develops rapidly. The charging system is used for providing energy supply for the operation of the electric automobile, is an important basic supporting system of the electric automobile, is also an important link in the commercialization and industrialization processes of the electric automobile, and has very important social benefits and economic benefits as an important matched infrastructure necessary for developing the electric automobile in the charging system.

The existing charging pile generally adopts a cabinet type structure, the interior of the charging pile comprises a fan (comprising a radiator), a power module, a CPU board and a power supply module, and the exterior of the charging pile is externally connected with a three-phase power supply. The three-phase power supply is connected with the power supply module and the power module and used for supplying power to the power supply module and the power module. The power supply module is used for detecting whether the three-phase power is in phase failure or not and supplying power to the CPU and the fan. The CPU is used for controlling the operation of the fan and the power module and receiving the feedback of the power supply module (the power supply feeds back whether the three-phase power supply is in a phase failure state). Wherein power module is as filling the inside important structure of electric pile, if the imperfection of protection, then probably can influence the life of whole internal circuitry. However, the prior art does not provide effective protection for the power module, and therefore, the present inventors need to devise a new technique to improve the problem.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a power control system for filling electric pile, it can provide the support on the hardware circuit for solving above-mentioned technical problem.

The technical scheme of the utility model is that:

a power control system for a charging post, comprising: the power supply comprises an input unit, a power conversion unit, an output unit, a current setting unit, an oscillation control unit, a main control unit and a protection unit, wherein the input unit comprises an input interface, an EMI (electro-magnetic interference) filter circuit and a rectification filter circuit which are sequentially connected, and the rectification filter circuit is connected with the power conversion unit; the power conversion unit comprises a first conversion circuit and a second conversion circuit, wherein the first conversion circuit and the second conversion circuit are respectively in inductive connection with the output unit and the oscillation control unit through transformers; the current setting unit is respectively connected with the output unit and the main control unit; the protection unit comprises an overvoltage protection unit, an overcurrent protection unit, a first over-temperature protection unit, a second over-temperature protection unit and a communication connector, wherein the overvoltage protection unit, the overcurrent protection unit, the first over-temperature protection unit and the second over-temperature protection unit are all connected with the communication connector, and the communication connector is connected with the main control unit.

Preferably, the overvoltage protection unit comprises a light emitting diode UD10A, a chip UD00, a triode UD10B, a diode DG00, an operational amplifier UG00A, a field effect tube QG00, a field effect tube QG01, a field effect tube QG02, a resistor RG02 and a resistor RG05, wherein the light emitting diode UD10A is connected with a first pin of the chip UD00, an emitter of the triode UD10B is connected with a positive input end of the operational amplifier UG00A after passing through a resistor RG02, and an output end of the operational amplifier UG00A is respectively connected with a gate of the field effect tube QG01 and a gate of the field effect tube QG 02; the drain electrode of the field effect transistor QG01 is connected with the communication connector after passing through the resistor RG05, the drain electrode of the field effect transistor QG00 is connected with the grid electrode of the field effect transistor QG02 after passing through the diode DG00, and the source electrode of the field effect transistor QG02 is grounded.

Preferably, the overcurrent protection unit comprises a field-effect tube QG10, a diode DG10, a field-effect tube QG11, a field-effect tube QG12, an operational amplifier UG00B and a resistor RG15, wherein the drain of the field-effect tube QG10 is connected with the gate of the field-effect tube QG12 after passing through the diode DG 10; the negative input end of the operational amplifier UG00B is connected with a reference voltage, and the output end of the operational amplifier UG00B is respectively connected with the grid of the field-effect tube QG11 and the grid of the field-effect tube QG 12; the drain electrode of the field effect transistor QG11 is connected with the communication connector through the resistor RG15, and the source electrode of the field effect transistor QG11 and the source electrode of the field effect transistor QG12 are both grounded.

Preferably, the first over-temperature protection unit comprises a first temperature control switch SWG20, a second temperature control switch SWG21, a resistor RG20, a resistor RG25, a resistor RG65, a capacitor CG20, a capacitor CG65, a transistor QG65, a field-effect tube QG21 and a field-effect tube QG22, wherein the first temperature control switch SWG20 and the second temperature control switch SWG21 are both connected with the gate of the field-effect tube QG21 and the gate of the field-effect tube QG 22; the resistor RG65 and the capacitor CG65 are arranged between the base electrode and the emitter electrode of the triode QG65 in parallel, and the collector electrode of the triode QG65 is respectively connected with the grid electrode of the field-effect tube QG21 and the grid electrode of the field-effect tube QG 22; the resistor RG20 and the capacitor CG20 are arranged between the gate and the source of the field effect transistor QG22 in parallel; the source electrode of the field effect transistor QG21 is connected with the communication connector through a resistor RG 25.

Preferably, the second over-temperature protection unit comprises a chip UG70, an operational amplifier UG80A, an operational amplifier UG80B, a resistor RG80, a resistor RG82, a resistor RG83, a resistor RG84, and a resistor RG85, wherein a third pin of the chip UG70 is connected to a positive input terminal of the operational amplifier UG80A, and the resistor RG80 is disposed between a negative input terminal and an output terminal of the operational amplifier UG 80A; the output end of the operational amplifier UG80A is connected with the negative input end of the operational amplifier UG80B, the positive input end of the operational amplifier UG80B is respectively connected with the resistor RG84 and the resistor RG85, and the other end of the resistor RG85 is grounded; the output end of the operational amplifier UG80B is connected with the communication connector after passing through the resistor RG82 and the resistor RG 83.

Preferably, the oscillation control unit comprises an oscillation chip U630, a transformer winding TC05A end, a transformer winding TC25A end, a transformer winding TC10C end, a transformer winding TC30C end, a zener diode DF00, a zener diode DF10, a zener diode DF20, a zener diode DF21, a resistor RF00, a resistor RF10, a resistor RF02, a resistor RF12, a resistor RF30, a capacitor CF00, a capacitor CF10, a transistor QF00, a transistor QF01, a transistor QF10 and a transistor QF11, wherein the transformer winding TC05A end is connected with the emitters of the transistor QF00 and the transistor QF01 respectively after passing through the resistor RF00 and the capacitor CF00 in sequence, the bases of the transistor QF00 and the transistor 01 are connected with the fourteenth pin of the oscillation chip U630 after passing through the resistor RF02, and the zener diode DF00 is arranged in parallel at two ends of the capacitor CF 00; the terminal of the transformer winding TC25A is connected with the emitting electrodes of the triode QF10 and the triode QF11 respectively after sequentially passing through the resistor RF10 and the capacitor CF10, the base electrodes of the triode QF10 and the triode QF11 are connected with the eleventh pin of the oscillating chip U630 after passing through the resistor RF12, and the zener diode DF10 is arranged at the two ends of the capacitor CF10 in parallel; the terminal TC10C of the transformer winding is connected with the ninth pin of the oscillating chip U630 after passing through a voltage stabilizing diode DF20 and a resistor RF30 in sequence; and the end of the transformer winding TC30C is connected with the ninth pin of the oscillating chip U630 after passing through a voltage stabilizing diode DF21 and a resistor RF30 in sequence.

Preferably, the current setting unit comprises an operational amplifier UF00A, an operational amplifier UF20A, an operational amplifier UF00B, an operational amplifier UF10B, an operational amplifier UF20B, a diode DE10, a resistor RE02, a resistor RE03, a resistor RE08, a resistor RE11, a resistor RE18 and a capacitor CE03, wherein a fifth pin of the operational amplifier UF00B is connected with the main control unit through the resistor RE02, and the resistor RE02, the resistor RE03 and the capacitor CE03 are arranged between the fifth pin of the operational amplifier UF00B and the first pin of the operational amplifier UF00A in parallel; the seventh pin of the operational amplifier UF00B is connected with the fifth pin of the operational amplifier UF20B through a diode DE 10; the fifth pin of the operational amplifier UF10B is connected with the output unit through a resistor RE11, and the seventh pin of the operational amplifier UF10B is connected with the sixth pin of the operational amplifier UF20B through a resistor RE 18.

Preferably, the output unit includes a transformer winding TC15C end, a transformer winding TC35C end, a diode DC50, a diode DC51, a diode DC60, a diode DC61, an inductor LC50, an inductor LC60, an output interface J5, an output interface J6, a capacitor CC90, a capacitor CC91, and a capacitor CC92, wherein the transformer winding TC15C end is connected to the output interface J5 after passing through the diode DC51 and the inductor LC50 in sequence, and the diode DC51 is connected in parallel to two ends of the diode DC 50; the terminal of the transformer winding TC35C is connected with an output interface J5 after passing through a diode DC61 and an inductor LC60 in sequence, and a diode DC61 is connected with two ends of a diode DC60 in parallel; the capacitor CC90, the capacitor CC91 and the capacitor CC92 are connected in parallel between the output interface J5 and the output interface J6.

Preferably, the first conversion circuit comprises a transformer winding TC05B end, a transformer winding TC05C end, a transformer winding TC15A end, a transformer winding TC15B end, a field effect tube QC00, a field effect tube QC10, a diode DC04, a diode DC14, a capacitor CC00, a capacitor CC10, a resistor RC00, a resistor RC01, a resistor RC10 and a resistor RC11, wherein the transformer winding TC05B end is connected with the gate of the field effect tube QC00 after passing through the resistor RC00 and the resistor RC01 in sequence, and the capacitor CC00 and the diode DC04 are connected in series between the drain and the source of the field effect tube QC 00; the end of the transformer winding TC05C is connected with the grid of a field effect tube QC10 after sequentially passing through a resistor RC10 and a resistor RC11, and a capacitor CC10 and a diode DC14 are connected between the drain and the source of the field effect tube QC10 in series; the source electrode of the field effect transistor QC00 is connected with the end of the transformer winding TC15A, and the drain electrode of the field effect transistor QC10 is connected with the end of the transformer winding TC 15B.

Preferably, the second conversion circuit comprises a transformer winding TC25B end, a transformer winding TC25C end, a transformer winding TC35A end, a transformer winding TC35B end, a field effect tube QC20, a field effect tube QC30, a diode DC24, a diode DC34, a capacitor CC20, a capacitor CC30, a resistor RC20, a resistor RC21, a resistor RC30 and a resistor RC31, wherein the transformer winding TC25B end is connected with the gate of the field effect tube QC20 after passing through the resistor RC20 and the resistor RC21 in sequence, and the capacitor CC20 and the diode DC24 are connected in series between the drain and the source of the field effect tube QC 20; the end of the transformer winding TC25C is connected with the grid of a field effect tube QC30 after sequentially passing through a resistor RC30 and a resistor RC31, and a capacitor CC30 and a diode DC34 are connected between the drain and the source of the field effect tube QC30 in series; the source electrode of the field effect transistor QC20 is connected with the end of the transformer winding TC35A, and the drain electrode of the field effect transistor QC30 is connected with the end of the transformer winding TC 35B.

Adopt above-mentioned technical scheme, the utility model discloses at least, include following beneficial effect:

a power control system for filling electric pile, have excessive pressure, overflow, connect anti-and dual excess temperature protect function, protection power module that can be better improves the life of whole circuit.

Drawings

Fig. 1 is a schematic diagram of a power control system for a charging pile according to the present invention;

fig. 2 is a circuit diagram of an input unit according to the present invention;

fig. 3 is a circuit diagram of a power conversion unit according to the present invention;

fig. 4 is a circuit diagram of an output unit according to the present invention;

fig. 5 is a circuit diagram of a current setting unit according to the present invention;

fig. 6 is a circuit diagram of the oscillation control unit according to the present invention;

fig. 7 is a circuit diagram of the main control unit according to the present invention;

fig. 8 is a circuit diagram of a protection unit according to the present invention;

fig. 9 is a partial circuit diagram of the overvoltage protection unit according to the present invention;

fig. 10 is a circuit diagram of a reference voltage circuit according to the present invention;

fig. 11 is a circuit diagram of the over-current detection circuit of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

As shown in fig. 1 to 11, in order to comply with the present invention, a power control system for charging pile includes: the power supply comprises an input unit, a power conversion unit, an output unit, a current setting unit, an oscillation control unit, a main control unit and a protection unit, wherein the input unit comprises an input interface, an EMI (electro-magnetic interference) filter circuit and a rectification filter circuit which are sequentially connected, and the rectification filter circuit is connected with the power conversion unit; the power conversion unit comprises a first conversion circuit and a second conversion circuit, wherein the first conversion circuit and the second conversion circuit are respectively in inductive connection with the output unit and the oscillation control unit through transformers; the current setting unit is respectively connected with the output unit and the main control unit; the protection unit comprises an overvoltage protection unit, an overcurrent protection unit, a first over-temperature protection unit, a second over-temperature protection unit and a communication connector, wherein the overvoltage protection unit, the overcurrent protection unit, the first over-temperature protection unit and the second over-temperature protection unit are all connected with the communication connector, and the communication connector is connected with the main control unit.

Preferably, the EMI filter circuit includes an inductor T1A, an inductor T1B, an inductor T1C, a variable resistor VR1, a variable resistor VR2, and a variable resistor VR3, and the rectifier filter circuit includes, but is not limited to, a rectifier bridge BD, an inductor L4, and an inductor LB95, where the input interfaces are respectively connected to one ends of the inductor T1A, the inductor T1B, and the inductor T1C, and the other ends of the inductor T1A, the inductor T1B, and the inductor T1C are connected to the rectifier bridge BD; the variable resistor VR1 is arranged between the inductor T1A and the inductor T1B, the variable resistor VR2 is arranged between the inductor T1B and the inductor T1C, and the variable resistor VR3 is arranged between the inductor T1A and the inductor T1C; the first pin of the rectifier bridge BD is connected with the first conversion circuit after passing through the inductor L4 and the inductor LB95 in sequence, and the fifth pin of the rectifier bridge BD is connected with the second conversion circuit.

Preferably, the master control unit includes a master control chip U14, and more preferably, the model of the master control chip U14 is STM32F 407R. The 6 th pin of the communication connector is connected with the 39 th pin of the main control chip U14 through an operational amplifier and an analog switch, and the 13 th pin of the communication connector is connected with the 39 th pin of the main control chip U14 through an operational amplifier and an analog switch; the 7 th pin of the main control chip is connected with the 30 th pin of the main control chip U14 through an operational amplifier; the 14 th pin is connected with the 30 th pin of the main control chip U14 through an operational amplifier, and various information displays are realized through the control of the main control chip U14.

Preferably, a reference voltage circuit is further included for providing various reference voltages (5V, 2.5V) to the protection circuit. The circuit comprises a chip UG00C (with the model of LM393D), a chip UG80C (with the model of LM358D), a chip UG40 (with the model of TL431A), a capacitor C700, a capacitor CG80, a capacitor CG40 and a resistor RG40, wherein the fourth pin of the chip UG00C is grounded, and the capacitor C700 is arranged between the fourth pin and the eighth pin of the chip UG 00C; the fourth pin of the chip UG80C is grounded, and the capacitor CG80 is arranged between the fourth pin and the eighth pin of the chip UG 80C; the eighth pin of the chip UG80C is connected with the first pin of the chip UG40 after passing through the resistor RG40, the eighth pin of the chip UG40 outputs +2.5V voltage, and the second pin, the third pin, the sixth pin and the seventh pin of the chip UG40 are all grounded.

Preferably, the overcurrent protection unit further comprises an overcurrent detection circuit, which comprises a resistor RF85, a resistor RF83, a resistor RF80, a resistor RF75, a resistor RF50, a resistor RF70, an operational amplifier UF80B (model LM358D), an operational amplifier UF80A (model LM358D), a chip UF80C (model LM358D), a capacitor CF72 and a capacitor CF80, wherein one end of the resistor RF85 is connected with the output unit of the power module, the other end of the resistor RF85 is connected with the sixth pin of the operational amplifier UF80B, and the seventh pin of the operational amplifier UF80B is connected with the sixth pin of the communication connector after passing through the resistor RF83, that is, the HPM-CURR-RDBK-post 8 in the overcurrent detection circuit is connected with the SHT7-HPM-CURR-RDBK-POS end; the seventh pin of the operational amplifier UF80B is directly connected with the gate of a field effect transistor QG10 in the overcurrent protection unit, namely the OUT-SNSsht8 is connected with the SHT7OUT-SNS terminal; the fifth pin of the operational amplifier UF80B is connected with the thirteenth pin of the communication connector after passing through the resistor RF80 and the resistor RF75 in sequence, namely the HPM-CURR-RDBK-NEGsht8 in the over-current detection circuit is connected with the SHT7-HPM-CURR-RDBK-NEG end; the eighth pin of the chip UF80C is connected with +15V voltage through a resistor RF50, the fourth pin is grounded, and a capacitor CF80 is arranged between the fourth pin and the eighth pin; one end of the resistor RF70 is connected with +5V voltage, the other end of the resistor RF70 is connected with the third pin of the operational amplifier UF80A, the second pin of the operational amplifier UF80A is grounded after passing through the capacitor CF72, and the first pin of the operational amplifier UF80A is connected with the fifth pin of the operational amplifier UF80B after passing through the resistor RF 80.

Preferably, all transformers in the present embodiment are high frequency transformers (model number BK3135-KH 3277).

Preferably, the communication connector is model number 43045-.

Preferably, the model of the chip UD00 is TL431A, and the model of the operational amplifier UG00A is LM 393D.

Preferably, the model of the operational amplifier UG00B is LM 393D.

Preferably, the first temperature control switch SWG20 is 67F080, and the second temperature control switch SWG21 is 67F 090.

Preferably, the model of the chip UG70 is LM26CIM 5.

Preferably, the operational amplifier UG80A and the operational amplifier UG80B are both LM 358D.

Preferably, the models of the operational amplifier UF00A, the operational amplifier UF20A, the operational amplifier UF00B, the operational amplifier UF10B and the operational amplifier UF20B are LM 358D.

Preferably, the model of the oscillating chip U630 is UC 3825A.

Preferably, the model of the rectifier bridge BD is MT 3516.

The working principle of the embodiment is as follows: the three-phase power supply is connected with an external three-phase power supply through an input interface, sine alternating current is connected into the three-phase power supply, then the sine alternating current is converted into direct current through an EMI filter circuit and a rectification filter circuit, the direct current is converted into square wave alternating current through a power conversion unit, and the square wave alternating current is converted into direct current after being rectified and filtered by a transformer on an output unit and used for supplying power to a battery.

The EMI filter circuit can not only improve the power factor of a line or a system, but also solve the problems of electromagnetic interference (EMI) and electromagnetic compatibility (EMC), and the EMI filter circuit adopts discrete devices, so that the EMI filter circuit is convenient to replace and maintain.

Be provided with a electric capacity CB97 between the high level output of input unit and the low level output, on the one hand, because the characteristic that the both ends voltage of electric capacity can not break suddenly, at this output cross-over connection 1uf following little electric capacity, the interference that the high frequency clutter pulse that can the filtering electric wire netting brought can reduce clutter electron degree circuit has also suppressed the pollution of this circuit work clutter to the electric wire netting simultaneously. On the other hand, a large capacitor is connected across the output terminal, so that the reactive current of the inductive load of the circuit can be absorbed, and the reactive power consumption can be reduced. In this regard, a person skilled in the art may set the size of the capacitor according to actual use requirements, which is not limited in this embodiment.

The power conversion unit is used for converting direct current into square wave alternating current and outputting the square wave alternating current, and the first conversion circuit is connected with the high-level output end of the input unit and used for outputting positive square wave alternating current. The second conversion circuit is connected with the low-level output end of the input unit and used for outputting negative square wave alternating current.

The output unit is in inductive connection with the power conversion unit, wherein the terminal of the transformer winding TC15C is in inductive connection with the terminal of the transformer winding TC15A, and the terminal of the transformer winding TC35C is in inductive connection with the terminal of the transformer winding TC 35A. The power conversion unit transmits the square wave alternating current to the output unit, and the output unit is rectified and filtered by a diode, a capacitor, an inductor and other components and then is output through an output interface J5 and an output interface J6.

Specifically, the first conversion circuit and the second conversion circuit are arranged completely symmetrically. A transformer winding TC15A end, a field effect tube QC00, a diode DC04, a capacitor CC00, a transformer winding TC15B end, a field effect tube QC10, a diode DC14, a capacitor CC10 and the like in the first conversion circuit form a converter. And the transformer winding TC35A end, the field-effect tube QC20, the diode DC24, the capacitor CC20, the transformer winding TC35B end, the field-effect tube QC30, the diode DC34, the capacitor CC30 and the like in the second conversion circuit form another converter. The diode DC50, the diode DC51, the diode DC60 and the diode DC61 are rectifier diodes on the secondary side of the transformer; the diodes DC55 and DC56 are freewheeling diodes; the inductor LC50 and the inductor LC60 are output filter inductors; the capacitor CC70, the capacitor CC71, the capacitor CC75 and the capacitor CC76 are filter capacitors. The principle of the magnetic reset transformer lies in that after one path of the transformer is switched off, after a short dead time, the load current flows after passing through the freewheeling diode, the magnetizing current of the transformer is gradually reduced to zero, and the magnetic reset and energy feedback of the iron core are realized. Then another transformer starts to work, the exciting current of another set of transformers is gradually increased, and the previous process is repeated. The two paths work alternately in a mode of phase difference of 180 degrees. The circuit adopts two paths of alternate work, so that on one hand, the switching stress is reduced, on the other hand, a complex magnetic reset circuit is omitted, and the transformer can be reliably reset. Each circuit path is composed of a field effect transistor and a diode, and a straight-through phenomenon cannot occur. It is known that the conventional full bridge circuit has a direct connection risk, and has higher circuit matching requirements and poor stability. By adopting the structure of the embodiment, the feedback of the excitation energy can be realized without adding other loops, the structure is simple, and the loss is low. Meanwhile, the parallel structure reduces the volume of the output filter inductor and reduces the stress of the device, thereby reducing the loss. The circuit has the advantages of good reliability, high frequency, good square waveform, simple process and good market application prospect.

Preferably, the output unit further includes a chip UC80 (preferably an ACS758 chip) and a chip UC85 (preferably an ACS758 chip), and is configured to detect the output current, feed back the current magnitude to the main control unit, and implement control over the output current through the main control unit. The third pin of the chip UC80 is connected with an overcurrent protection unit; the third pin of the chip UC85 is connected to a current setting unit, and by comparing with the set current, the enable terminal controls the signal output.

And a current setting unit, wherein the HPM-CURR-SET-POS terminal and the HPM-CURR-SET-NEG terminal are connected with a main control chip U14(30 pins) through an operational amplifier, and the current is SET through a main control chip U14. The terminal OUT-CURR-RB is connected with the terminal OUT-CURR-RB-SHT5 of the output unit, is used for acquiring actual current, and the magnitude of the current can be adjusted through a potentiometer RE14 and a potentiometer RE 17. Then the set current and the actual current are compared at the operational amplifier UF20B, and when the actual current and the set current are output within a certain error range; and when the set current is larger than the actual current, enabling the control end to carry out output control. Namely, the precision control of the output current can be realized through the operational amplifier, and the circuit structure is simpler.

The oscillation control unit is used for controlling the oscillation of the power conversion unit, wherein the TC05A end of the transformer winding is connected with the TC15C end of the transformer winding in the power conversion unit in a mutual inductance mode; the terminal of the transformer winding TC25A is connected with the terminal of the transformer winding TC25C in the power conversion unit in a mutual inductance mode. An eleventh pin of the oscillation chip U630 induces the first oscillation signal to the second conversion circuit through electronic components such as a resistor RF12, a transistor QF10, a transistor QF11, a capacitor CF10, a resistor RF10, and a terminal of a transformer winding TC 25A. The fourteenth pin of the oscillation chip U630 induces the second oscillation signal to the first conversion circuit through electronic components such as the resistor RF02, the transistor QF00, the transistor QF01, the capacitor CF00, the resistor RF00, and the terminal of the transformer winding TC 05A. The oscillation control unit is matched with the power conversion unit to convert the direct current rectified and filtered by the input unit into square wave alternating current to be output. In addition, the end of a transformer winding TC10C in the oscillation control unit is connected with the end of a transformer winding TC10A in the power conversion unit in a mutual inductance way; the terminal of the transformer winding TC30C is connected with the terminal of the transformer winding TC30A in the power conversion unit in a mutual inductance mode. The mutual inductance of the transformer can be used for detecting the input current, then the judgment of the oscillation chip is carried out, when the input current is overlarge, the signal output is interrupted through the enabling end, the first conversion circuit and the second conversion circuit can be effectively protected, namely, when the current is overlarge, the first conversion circuit and the second conversion circuit are directly shut down. Current protection in the prior art is to output current detection, and this embodiment is at the circuit middle-end, or the input has just considered to carry out current detection, and its whole circuit of protection that can be better further improves holistic factor of safety, improves life.

The overvoltage protection unit is used for detecting and protecting the output voltage of the power module. Wherein sht3OUT + is a high level output end of the output unit, and sht3 OUT-is a low level output end of the output unit. When output by the forward voltage, the light emitting diode UD10A is turned on and emits light. The light emitting diode UD10A and the triode UD10B form a photoelectric coupler, the light emitting diode UD10A transmits an optical coupling signal to the triode UD10B, and the triode UD10B receives the optical coupling signal. And then comparing the voltage with +2.5V at the operational amplifier UG00A, when the voltage is overlarge, connecting the gate of the field effect transistor QG02 with a turn-off signal output end (SHT-DWN-Nsht6) to output a turn-off signal by turning off, wherein the turn-off signal is connected with the power module and used for turning off the power module. When the output voltage is in a normal range, the voltage signal is output and displayed through the main control unit through the field effect transistor QG01 and the communication connector. In addition, it is known that, if the positive and negative electrodes of the output terminal are connected reversely, a serious result may be caused, such as a circuit being burned out, and in order to avoid this, in this embodiment, a chip UD00 (model TL431A) is used in cooperation with a zener diode DD10 and a zener diode DD10 to perform reverse connection detection, if the positive and negative terminals of the high and low level are connected incorrectly, the two zener diodes are turned on, the chip UD00 detects that the voltage is reversed, and then a photocoupler formed by a diode UD10A (model CNY17-3X006) and a triode UD10B (model CNY17-3X006) is turned off, which is referred to the above and will not be described again. The embodiment adopts the optocoupler to realize the one-way transmission of signals, the input end and the output end are completely electrically isolated, the anti-interference capability is strong, the service life is long, and the transmission efficiency is high.

And the overcurrent protection unit is used for detecting and protecting the output current of the power module, wherein the overcurrent detection circuit is used for detecting the output current. The operational amplifier UF80A, the chip UF80C, the capacitor CF72, the capacitor CF80 and other components form a reference current generating circuit, the reference current generating circuit is connected with a fifth pin of the operational amplifier UF80B through a first pin of the operational amplifier UF80A, a sixth pin of the operational amplifier UF80B is connected with actual output current, then the actual output current is compared with the reference current, the current is connected with a main control unit through a communication connector, and output display is carried out through the main control unit. Meanwhile, when the voltage is compared with the +2.5V voltage at the operational amplifier UG00B and is overlarge, the gate of the field effect transistor QG12 is connected with a turn-off signal output end (SHT-DWN-Nsht6) to output a turn-off signal in an off mode, and the turn-off signal is connected with the power module and used for turning off the power module. When the output voltage is in a normal range, the voltage signal is output and displayed through the main control unit through the field effect transistor QG11 and the communication connector.

The first over-temperature protection unit is used for detecting and protecting the temperature of the power tube radiator. The first temperature control switch SWG20 and the second temperature control switch SWG21 are arranged on a heat dissipation sheet of the power tube radiator, when the temperature of the power tube radiator is too high, the temperature control switches are turned on, high-temperature signals sequentially pass through the triode QG65 and the field effect tube QG22 and then are transmitted to the output end of a turn-off signal, and a turn-off signal is output and connected with the power module and used for turning off the power module. When the temperature is in the normal range, the field effect transistor QG21 and the communication connector are connected with the main control unit, and the temperature is displayed under the control of the main control unit.

And the second over-temperature protection unit is used for realizing the temperature detection of the PCB, and the temperature detection is mainly realized through a temperature detection chip UG 70. When the temperature of the PCB is too high, the chip UG70 sends a high-temperature signal, and the high-temperature signal passes through the triode QG65 and the field-effect tube QG22 in sequence and then reaches the turn-off signal output end to output a turn-off signal, and the turn-off signal is connected with the power module and used for turning off the power module. When the temperature is in a normal range, the chip UG70 sends a normal temperature signal, and the normal temperature signal is connected with the main control unit after passing through the triode QG65, the field effect transistor QG21 and the communication connector in sequence, and the temperature is displayed under the control of the main control unit.

The utility model discloses have excessive pressure, overflow, connect anti-and dual excess temperature protection (radiator and PCB board temperature detection) function, protection power module that can be better improves the life of whole circuit. The circuit structure is improved, firstly, the EMI filter circuit is arranged, the power factor of a circuit or a system can be improved, more importantly, the problems of electromagnetic interference and electromagnetic compatibility can be solved, and the EMI filter circuit adopts discrete devices and is convenient to replace and maintain. And secondly, the power conversion unit works alternately in two paths, and each branch of the circuit consists of a field effect tube and a diode, so that a straight-through phenomenon cannot occur. Moreover, the input end and the output end are provided with current detection, so that the protection of the load can be realized, the protection of circuit structures such as a power conversion unit and a current setting unit can be realized, and the safety is higher.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A power control system for a charging post, comprising: the power supply comprises an input unit, a power conversion unit, an output unit, a current setting unit, an oscillation control unit, a main control unit and a protection unit, wherein the input unit comprises an input interface, an EMI (electro-magnetic interference) filter circuit and a rectification filter circuit which are sequentially connected, and the rectification filter circuit is connected with the power conversion unit; the power conversion unit comprises a first conversion circuit and a second conversion circuit, wherein the first conversion circuit and the second conversion circuit are respectively in inductive connection with the output unit and the oscillation control unit through transformers; the current setting unit is respectively connected with the output unit and the main control unit; the protection unit comprises an overvoltage protection unit, an overcurrent protection unit, a first over-temperature protection unit, a second over-temperature protection unit and a communication connector, wherein the overvoltage protection unit, the overcurrent protection unit, the first over-temperature protection unit and the second over-temperature protection unit are all connected with the communication connector, and the communication connector is connected with the main control unit.

2. The power control system for a charging pile of claim 1, characterized in that: the overvoltage protection unit comprises a light emitting diode UD10A, a chip UD00, a triode UD10B, a diode DG00, an operational amplifier UG00A, a field effect tube QG00, a field effect tube QG01, a field effect tube QG02, a resistor RG02 and a resistor RG05, wherein the light emitting diode UD10A is connected with a first pin of the chip UD00, an emitter of the triode UD10B is connected with a positive input end of the operational amplifier UG00A after passing through a resistor RG02, and an output end of the operational amplifier UG00A is respectively connected with a gate of the field effect tube QG01 and a gate of the field effect tube QG 02; the drain electrode of the field effect transistor QG01 is connected with the communication connector after passing through the resistor RG05, the drain electrode of the field effect transistor QG00 is connected with the grid electrode of the field effect transistor QG02 after passing through the diode DG00, and the source electrode of the field effect transistor QG02 is grounded.

3. The power control system for a charging pile of claim 1, characterized in that: the overcurrent protection unit comprises a field effect transistor QG10, a diode DG10, a field effect transistor QG11, a field effect transistor QG12, an operational amplifier UG00B and a resistor RG15, wherein the drain electrode of the field effect transistor QG10 is connected with the gate electrode of the field effect transistor QG12 after passing through the diode DG 10; the negative input end of the operational amplifier UG00B is connected with a reference voltage, and the output end of the operational amplifier UG00B is respectively connected with the grid of the field-effect tube QG11 and the grid of the field-effect tube QG 12; the drain electrode of the field effect transistor QG11 is connected with the communication connector through the resistor RG15, and the source electrode of the field effect transistor QG11 and the source electrode of the field effect transistor QG12 are both grounded.

4. The power control system for a charging pile of claim 1, characterized in that: the first over-temperature protection unit comprises a first temperature control switch SWG20, a second temperature control switch SWG21, a resistor RG20, a resistor RG25, a resistor RG65, a capacitor CG20, a capacitor CG65, a triode QG65, a field-effect tube QG21 and a field-effect tube QG22, wherein the first temperature control switch SWG20 and the second temperature control switch SWG21 are both connected with the gate of the field-effect tube QG21 and the gate of the field-effect tube QG 22; the resistor RG65 and the capacitor CG65 are arranged between the base electrode and the emitter electrode of the triode QG65 in parallel, and the collector electrode of the triode QG65 is respectively connected with the grid electrode of the field-effect tube QG21 and the grid electrode of the field-effect tube QG 22; the resistor RG20 and the capacitor CG20 are arranged between the gate and the source of the field effect transistor QG22 in parallel; the source electrode of the field effect transistor QG21 is connected with the communication connector through a resistor RG 25.

5. The power control system for a charging pile of claim 1, characterized in that: the second over-temperature protection unit comprises a chip UG70, an operational amplifier UG80A, an operational amplifier UG80B, a resistor RG80, a resistor RG82, a resistor RG83, a resistor RG84 and a resistor RG85, wherein a third pin of the chip UG70 is connected with a positive input end of the operational amplifier UG80A, and the resistor RG80 is arranged between a negative input end and an output end of the operational amplifier UG 80A; the output end of the operational amplifier UG80A is connected with the negative input end of the operational amplifier UG80B, the positive input end of the operational amplifier UG80B is respectively connected with the resistor RG84 and the resistor RG85, and the other end of the resistor RG85 is grounded; the output end of the operational amplifier UG80B is connected with the communication connector after passing through the resistor RG82 and the resistor RG 83.

6. The power control system for a charging pile of claim 1, characterized in that: the oscillation control unit comprises an oscillation chip U630, a transformer winding TC05A end, a transformer winding TC25A end, a transformer winding TC10C end, a transformer winding TC30C end, a zener diode DF00, a zener diode DF10, a zener diode DF20, a zener diode DF21, a resistor RF00, a resistor RF10, a resistor RF02, a resistor RF12, a resistor RF30, a capacitor CF 30, a triode QF 30 and a triode 30, wherein the transformer winding TC05 30 end is connected with emitters of the triode QF 30 and the triode QF 30 respectively after passing through the resistor RF30 and the capacitor CF 30 in sequence, bases of the triode QF 30 and the triode QF 30 are connected with a fourteenth pin of the oscillation chip U630 through the resistor RF30, and the zener diode is arranged at two ends of the capacitor CF 30 in parallel; the terminal of the transformer winding TC25A is connected with the emitting electrodes of the triode QF10 and the triode QF11 respectively after sequentially passing through the resistor RF10 and the capacitor CF10, the base electrodes of the triode QF10 and the triode QF11 are connected with the eleventh pin of the oscillating chip U630 after passing through the resistor RF12, and the zener diode DF10 is arranged at the two ends of the capacitor CF10 in parallel; the terminal TC10C of the transformer winding is connected with the ninth pin of the oscillating chip U630 after passing through a voltage stabilizing diode DF20 and a resistor RF30 in sequence; and the end of the transformer winding TC30C is connected with the ninth pin of the oscillating chip U630 after passing through a voltage stabilizing diode DF21 and a resistor RF30 in sequence.

7. The power control system for a charging pile of claim 1, characterized in that: the current setting unit comprises an operational amplifier UF00A, an operational amplifier UF20A, an operational amplifier UF00B, an operational amplifier UF10B, an operational amplifier UF20B, a diode DE10, a resistor RE02, a resistor RE03, a resistor RE08, a resistor RE11, a resistor RE18 and a capacitor CE03, wherein a fifth pin of the operational amplifier UF00B is connected with the main control unit through a resistor RE02, and the resistor RE02, the resistor RE03 and the capacitor CE03 are arranged between the fifth pin of the operational amplifier UF00B and a first pin of the operational amplifier UF00A in parallel; the seventh pin of the operational amplifier UF00B is connected with the fifth pin of the operational amplifier UF20B through a diode DE 10; the fifth pin of the operational amplifier UF10B is connected with the output unit through a resistor RE11, and the seventh pin of the operational amplifier UF10B is connected with the sixth pin of the operational amplifier UF20B through a resistor RE 18.

8. The power control system for a charging pile of claim 1, characterized in that: the output unit comprises a transformer winding TC15C end, a transformer winding TC35C end, a diode DC50, a diode DC51, a diode DC60, a diode DC61, an inductor LC50, an inductor LC60, an output interface J5, an output interface J6, a capacitor CC90, a capacitor CC91 and a capacitor CC92, wherein the transformer winding TC15C end is connected with the output interface J5 after passing through the diode DC51 and the inductor LC50 in sequence, and the diode DC51 is connected to two ends of the diode DC50 in parallel; the terminal of the transformer winding TC35C is connected with an output interface J5 after passing through a diode DC61 and an inductor LC60 in sequence, and a diode DC61 is connected with two ends of a diode DC60 in parallel; the capacitor CC90, the capacitor CC91 and the capacitor CC92 are connected in parallel between the output interface J5 and the output interface J6.

9. The power control system for a charging pile of claim 1, characterized in that: the first conversion circuit comprises a transformer winding TC05B end, a transformer winding TC05C end, a transformer winding TC15A end, a transformer winding TC15B end, a field effect tube QC00, a field effect tube QC10, a diode DC04, a diode DC14, a capacitor CC00, a capacitor CC10, a resistor RC00, a resistor RC01, a resistor RC10 and a resistor RC11, wherein the transformer winding TC05B end is connected with the gate of the field effect tube QC00 after sequentially passing through the resistor RC00 and the resistor RC01, and the capacitor CC00 and the diode DC04 are connected between the drain and the source of the field effect tube QC00 in series; the end of the transformer winding TC05C is connected with the grid of a field effect tube QC10 after sequentially passing through a resistor RC10 and a resistor RC11, and a capacitor CC10 and a diode DC14 are connected between the drain and the source of the field effect tube QC10 in series; the source electrode of the field effect transistor QC00 is connected with the end of the transformer winding TC15A, and the drain electrode of the field effect transistor QC10 is connected with the end of the transformer winding TC 15B.

10. The power control system for a charging pile of claim 1, characterized in that: the second conversion circuit comprises a transformer winding TC25B end, a transformer winding TC25C end, a transformer winding TC35A end, a transformer winding TC35B end, a field effect tube QC20, a field effect tube QC30, a diode DC24, a diode DC34, a capacitor CC20, a capacitor CC30, a resistor RC20, a resistor RC21, a resistor RC30 and a resistor RC31, wherein the transformer winding TC25B end is connected with the gate of the field effect tube QC20 after sequentially passing through the resistor RC20 and the resistor RC21, and the capacitor CC20 and the diode DC24 are connected between the drain and the source of the field effect tube QC20 in series; the end of the transformer winding TC25C is connected with the grid of a field effect tube QC30 after sequentially passing through a resistor RC30 and a resistor RC31, and a capacitor CC30 and a diode DC34 are connected between the drain and the source of the field effect tube QC30 in series; the source electrode of the field effect transistor QC20 is connected with the end of the transformer winding TC35A, and the drain electrode of the field effect transistor QC30 is connected with the end of the transformer winding TC 35B.