Utility model content
The technical problem that the utility model mainly solves is to provide a kind of new two-way isolation DC-DC converter, and it is simple for structure, applies extensivelyr, and practicality is stronger, and antijamming capability is stronger, and reliability is higher.
For solving the problems of the technologies described above, the technical scheme that the utility model adopts is: a kind of two-way isolation DC-DC converter is provided, and it comprises the first port, the second port, the first voltage and current isolation collecting unit, second voltage and electric current isolation collecting unit, processing module, the first filter circuit unit, the second filter circuit unit and bi-directional power conversion module.Wherein, in described the first port and described the second port one of optionally as the input of described two-way isolation DC-DC converter, and another one in the two is accordingly as output.Described the first voltage and current isolation collecting unit connects described the first port to gather the voltage and current of described the first port and to produce corresponding feedback signal.Described second voltage is connected described the second port to gather the voltage and current of described the second port and to produce corresponding feedback signal with electric current isolation collecting unit.Described processing module connects described the first voltage and current isolation collecting unit and described second voltage and electric current isolation collecting unit, gather to receive described the first voltage and current isolation collecting unit and described second voltage and electric current isolation the described feedback signal being produced, and export corresponding control signal according to described feedback signal.Described the first filter circuit unit is connected to described the first port by described the first voltage and current isolation collecting unit.Described the second filter circuit unit is connected to described the second port by described second voltage and electric current isolation collecting unit.Described bi-directional power conversion module connects described processing module, and be connected to described the first port by described the first filter circuit unit and described the first voltage and current isolation collecting unit, and being connected to described the second port by described the second filter circuit unit and described second voltage and electric current isolation collecting unit, described bi-directional power conversion module is carried out the conversion between different voltage according to the described control signal of described processing module output between described the first port and described the second port.
Wherein, described two-way isolation DC-DC converter further comprises the first Electromagnetic interference filter unit and the second Electromagnetic interference filter unit.Described the first Electromagnetic interference filter unit is connected between described the first port and described the first voltage and current isolation collecting unit; Described the second Electromagnetic interference filter unit is connected between described the second port and described second voltage and electric current isolation collecting unit.
Wherein, described bi-directional power conversion module comprises transformer, the first switches set, second switch group, the first control switch, the first driver element, the first diode, the second control switch, the second driver element and the second diode.Described transformer at least comprise the first winding to the second winding pair, wherein, described the first winding is to comprising corresponding the first left side winding and the first right side winding, described the second winding is to comprising corresponding the second left side winding and the second right side winding.Described the first switches set is used for controlling described the first winding to whether working, wherein, described the first switches set comprises corresponding the first left way switch and the first right wing switch, one end of the described first left side winding of described the first winding centering is connected to described the first filter circuit unit by described the first left way switch, and one end of the described first right side winding of described the first winding centering is connected to described the second filter circuit unit by described the first right wing switch.Described second switch group is used for controlling described the second winding to whether working, wherein, described second switch group comprises corresponding the second left way switch and the second right wing switch, one end of the second left side winding of described the second winding centering is connected to described the first filter circuit unit by described the second left way switch, and one end of the described second right side winding of described the second winding centering is connected to described the second filter circuit unit by described the second right wing switch.Described the first control switch comprises the first path terminal, alternate path end and control end, wherein, the other end of the described second left side winding of the other end of the described first left side winding of described the first winding centering and described the second winding centering is connected to respectively described first path terminal of described the first control switch, the described alternate path end ground connection of described the first control switch.The described control end that described the first driver element connects described the first control switch is to control the whether conducting of described first path terminal of described the first control switch and described alternate path end.Described the first diode reverse is connected in parallel between described first path terminal and described alternate path end of described the first control switch.Described the second control switch comprises the first path terminal, alternate path end and control end, wherein, the other end of the described second right side winding of the other end of the described first right side winding of described the first winding centering and described the second winding centering is connected to respectively described first path terminal of described the second control switch, the described alternate path end ground connection of described the second control switch.The described control end that described the second driver element connects described the second control switch is to control the whether conducting of described first path terminal of described the second control switch and described alternate path end.Described the second diode reverse is connected in parallel between described first path terminal and described alternate path end of described the second control switch.Wherein, the control signal of described processing module output comprises first pair of control signal, second pair of control signal, the first pulse-width signal and the second pulse-width signal, described the first switches set receives described first pair of control signal to control described the first winding to whether working, and described second switch group receives described second pair of control signal to control described the second winding to whether working; Described the first driver element receives described the first pulse-width signal to control the whether conducting of described the first path terminal in described the first control switch and described alternate path end according to described the first pulse-width signal, and described the second driver element receives described the second pulse-width signal to control the whether conducting of described the first path terminal in described the second control switch and described alternate path end according to described the second pulse-width signal.
Wherein, described bi-directional power conversion module further comprises the first absorptive unit and the second absorptive unit.Described the first absorptive unit is connected in parallel between described first path terminal and described alternate path end of described the first control switch; Described the second absorptive unit is connected in parallel between described first path terminal and described alternate path end of described the second control switch.
Wherein, described processing module comprises the first pulse width modulation controlled unit and the second pulse width modulation controlled unit.Described the first pulse width modulation controlled unit connects described second voltage and electric current isolation collecting unit isolates to receive described second voltage and electric current the described feedback signal that collecting unit was produced, and exports described the first pulse-width signal to described the first driver element.Described the second pulse width modulation controlled unit connects described the first voltage and current isolation collecting unit and isolates to receive described the first voltage and current the described feedback signal that collecting unit was produced, and exports described the second pulse-width signal to described the second driver element.
Wherein, described the first voltage and current isolation collecting unit and described second voltage and electric current isolation collecting unit comprise respectively electric current isolation collecting unit and voltage isolation collecting unit.Described electric current isolation collecting unit is for the electric current of described the first port or described the second port is isolated to collection, and the voltage bias signal that the current conversion gathering is become to isolate.Described voltage isolation collecting unit, for the voltage of described the first port or described the second port is isolated to collection, and becomes voltage feedback signal by the voltage transitions of collection.
Wherein, described electric current isolation collecting unit comprises the current sensor based on Hall effect, and described voltage isolation collecting unit comprises the first light coupling relay, the second light coupling relay, programmable a reference source and the 3rd light coupling relay.Described the first light coupling relay comprises light-emitting component and optical coupled switch, and one end of wherein said light-emitting component is connected to the first power supply by the first resistance, and its other end receives the 3rd control signal; The control end of described optical coupled switch and described light-emitting component are coupled, and one path terminal is connected to the first collection voltage, and another path terminal is by the second resistance and the 3rd grounding through resistance, wherein, described another path terminal is as first node, and junction between described the second resistance and described the 3rd resistance is as Section Point.Described the second light coupling relay comprises light-emitting component and optical coupled switch, and wherein, one end of described light-emitting component is connected to described the first power supply by the 4th resistance, and its other end receives the 4th control signal; The control end of described optical coupled switch and described light-emitting component are coupled, and one path terminal is connected to described Section Point, and another path terminal is by the 5th grounding through resistance.One end of described programmable a reference source is connected to described first node by the 6th resistance, its other end ground connection, and its control end is connected to described Section Point.Described the 3rd light coupling relay comprises light-emitting component and optical coupled switch, and one end of wherein said light-emitting component is connected to described first node by the 7th resistance, and its other end is connected to the junction between described the 6th resistance and described programmable a reference source; The control end of described optical coupled switch and described light-emitting component are coupled, and one path terminal is connected to by the 8th resistance the fixed reference voltage that described the first pulse width modulation controlled unit or described the second pulse width modulation controlled unit produce, and its another path terminal is passed through the 9th grounding through resistance, and the output that described another path terminal is isolated collecting unit as described voltage is to export described voltage feedback signal.
Wherein, described the first pulse width modulation controlled unit and described the second pulse width modulation controlled unit comprise respectively PDM keyer, wherein, and integrated two-way error amplifier described fixed reference voltage is provided in described PDM keyer.
Wherein, described the first left way switch in described the first switches set and described the first right wing switch comprise respectively the 4th light coupling relay and switch element.Described the 4th light coupling relay comprises light-emitting component and optical coupled switch, and one end of wherein said light-emitting component is connected to described the first power supply by the 11 resistance, and its other end receives the corresponding control signal in described first pair of control signal; The control end of described optical coupled switch and described light-emitting component are coupled, one path terminal ground connection, and another path terminal is connected to described the first filter circuit unit or described the second filter circuit unit as the port of described bi-directional power conversion module after by the 12 resistance and the 13 resistance.The control end of described switch element is connected to the node between described the 12 resistance and described the 13 resistance, one path terminal is connected to described the first filter circuit unit or described the second filter circuit unit, and another path terminal is connected to the described first left side winding of described the first winding centering or one end of described the first right side winding.
Wherein, described the second left way switch and described the second right wing switch in described second switch group comprise respectively relay and switch element, and described relay is connected between the described second left side winding or described the second right side winding of described the first filter circuit unit or described the second filter circuit unit and described the second winding centering; The control end of described switch element receives the corresponding control signal in described second pair of control signal, one path terminal ground connection, and another path terminal is connected to described relay.
The beneficial effects of the utility model are: the situation that is different from prior art, the structural design of two-way isolation DC-DC isolator of the present utility model has symmetry, structure is very succinct and ingenious, and its compatibility the voltage transformation between change in voltage or high-tension battery group and accessory power supply between the high-tension battery group group of the voltage transformation between battery unit and series connection in high-tension battery group group, its application is more extensive.Separately, two-way isolation DC-DC isolator of the present utility model can be realized constant voltage and the constant current control of both sides, and can be as required, automatically change constant voltage value and constant current value, practicality is stronger, and its not only input and output isolation, and relevant collecting unit and control unit are also isolated, antijamming capability is stronger, and reliability is higher, has improved electromagnetic compatibility characteristic.
Embodiment
Refer to Fig. 1, it is the schematic diagram of the two-way isolation DC-DC converter shown in the utility model one embodiment.As shown in Figure 1, two-way isolation DC-DC converter 100 of the present utility model comprises the first port 110, the second port one 20, the first voltage and current isolation collecting unit 130, second voltage and electric current isolation collecting unit 140, processing module 150, the first filter circuit unit 161, the second filter circuit unit 162 and bi-directional power conversion module 170.
Wherein, in the first port 110 and the second port one 20 one optionally as the input of two-way isolation DC-DC converter 100, and another one in the two is accordingly as the output of two-way isolation DC-DC converter 100.That is to say, when the first port 110 is during as input, the second port one 20 is as output; Otherwise when the second port one 20 is during as input, the first port 110 is as output.
Thereby the first voltage and current isolation collecting unit 130 connects the first port 110 and produces corresponding feedback signal with the voltage and current that gathers the first port 110 places; Thereby second voltage is connected the second port one 20 with electric current isolation collecting unit 140 produces corresponding feedback signal with the voltage and current that gathers the second port one 20 places.
Processing module 150 connects the first voltage and current isolation collecting unit 130 and second voltage and electric current isolation collecting unit 140, the feedback signal being produced to receive the first voltage and current isolation collecting unit 130 and second voltage and electric current isolation collecting unit 140, and export corresponding control signal according to feedback signal.In the utility model, processing module 150 can be Embedded processing module, for example micro-control unit (Micro Controller Unit, MCU), central processing unit (Central Processing Unit, or arm processor CPU), it is taking embedded software as core, and peripheral circuit flexible configuration as required.
The first filter circuit unit 161 is connected to the first port 110 by the first voltage and current isolation collecting unit 130, and the second filter circuit unit 162 is connected to the second port one 20 by second voltage and electric current isolation collecting unit 140.Wherein, the first filter circuit unit 161 and the second filter circuit unit 162 can adopt respectively capacitor filter, or LC filter circuit or π filter circuit.
Bi-directional power conversion module 170 connects processing module 150, and be connected to the first port 110 by the first filter circuit unit 161 and the first voltage and current isolation collecting unit 130, and be connected to the second port one 20 by the second filter circuit unit 162 and second voltage and electric current isolation collecting unit 140.The control signal that bi-directional power conversion module 170 can be exported according to processing module 150 and carry out the conversion between different voltage between the first port 110 and the second port one 20.
Particularly, bi-directional power conversion module 170 can be the flyback power supply structure of two-way isolation, and it comprises transformer 171, the first switches set 172, second switch group 173, the first control switch 174, the first driver element 175, the first diode 176, the second control switch 177, the second driver element 178 and the second diode 179.
Wherein, transformer 171 at least comprise the first winding to 171a and the second winding to 171b, wherein, the first winding comprises corresponding the first left side winding 1711 and the first right side winding 1712 to 171a, and the second winding comprises corresponding the second left side winding 1715 and the second right side winding 1716 to 171b.The first winding can be set as 1 to the first left side winding 1711 in 171a and the turn ratio of the first right side winding 1712, and the second winding also can be set as 1 to the second left side winding 1715 in 171b and the turn ratio of the second right side winding 1716.
Whether the first switches set 172 works to 171a for controlling the first winding, and it comprises corresponding the first left way switch 1721 and the first right wing switch 1722.Wherein, the first winding is connected to the first filter circuit unit 161 to one end of the first left side winding 1711 in 171a by the first left way switch 1721, and the first winding is connected to the second filter circuit unit 162 to one end of the first right side winding 1712 in 171a by the first right wing switch 1722.
Whether second switch group 173 works to 171b for controlling the second winding, and it comprises corresponding the second left way switch 1731 and the second right wing switch 1732.Wherein, the second winding is connected to the first filter circuit unit 161 to one end of the second left side winding 1715 in 171b by the second left way switch 1731, and the second winding is connected to the second filter circuit unit 162 to one end of the second right side winding 1716 in 171b by the second right wing switch 1732.
The first control switch 174 comprises the first path terminal, alternate path end and control end.Wherein, the other end of the first winding to the first left side winding 1711 in 171a and the second winding are connected to respectively the first path terminal of the first control switch 174 to the other end of the second left side winding 1715 in 171b, and the alternate path end ground connection of the first control switch 174.
The control end that the first driver element 175 connects the first control switch 174 is to control the whether conducting of the first path terminal of the first control switch 174 and alternate path end.In the present embodiment, the first control switch 174 can adopt PMOS pipe and realize, and its grid is as control end, and a source/drain electrode is as the first path terminal, and another source/drain electrode is as alternate path end.
The first diode 176 is connected in reverse parallel between first path terminal and alternate path end of the first control switch 174.
Similarly, the second control switch 177 comprises the first path terminal, alternate path end and control end.Wherein, the other end of the first winding to the first right side winding 1712 in 171a and the second winding are connected to respectively the first path terminal of the second control switch 177 to the other end of the second right side winding 1716 in 171b, and the alternate path end ground connection of the second control switch 177.
The control end that the second driver element 178 connects the second control switch 177 is to control the whether conducting of the first path terminal of the second control switch 177 and alternate path end.In the present embodiment, the second control switch 177 also can adopt PMOS pipe and realize, and its grid is as control end, and a source/drain electrode is as the first path terminal, and another source/drain electrode is as alternate path end.
The second diode 179 is connected in reverse parallel between first path terminal and alternate path end of the second control switch 177.
In addition,, in the utility model, bi-directional power conversion module 170 may further include the first absorptive unit 1701 and the second absorptive unit 1702.Wherein, the first absorptive unit 1701 is connected in parallel between first path terminal and alternate path end of the first control switch 174, and the second absorptive unit is connected in parallel between first path terminal and alternate path end of the second control switch 177.The first absorptive unit 1701 and the second absorptive unit 1702 can adopt RC absorbing circuit, or adopt RCD absorbing circuit.
The first left way switch 1721 and the first right wing switch 1722 in the first switches set 172 can be the switching circuit based on PMOS pipe or the switching circuit based on relay.Accordingly, the second left way switch 1731 in the first switches set 173 and the second right wing switch 1732 are the switching circuit based on relay or the switching circuit based on PMOS pipe.The first driver element 175 and the second driver element 178 can adopt combination or the isolation drive chip portfolio of non-polar capacitor combination or bus buffer and polarity free capacitor.
The control signal that processing module 150 is exported comprises first pair of control signal, second couple of control signal, the first pulse-width signal PWM_LEFT and the second pulse-width signal PWM_RIGHT.Wherein first pair of control signal comprises the first left side control signal LEFT_HIGH and the first right side control signal RIGHT_HIGH, and whether the first left side control signal LEFT_HIGH and the first right side control signal RIGHT_HIGH that the first left way switch 1721 in the first switches set 172 and the first right wing switch 1722 receive respectively in the first control signal work to 171a to control the first winding.Second pair of control signal comprises the second left side control signal LEFT_LOW and the second right side control signal RIGHT_LOW, and whether the second left side control signal LEFT_LOW and the second right side control signal RIGHT_LOW that the second left way switch 1731 in second switch group 173 and the second right wing switch 1732 receive respectively in second pair of control signal work to 171b to control the second winding.Wherein, the first left way switch 1721 in the first switches set 172 and the first right wing switch 1722 conducting simultaneously or shutoffs, to carry out the first change in voltage, for example change in voltage between any one battery pack and accessory power supply in series battery.And the second left way switch 1731 in second switch group 173 and the second right wing switch 1732 conducting simultaneously or shutoffs, to carry out the second change in voltage, for example change in voltage of the battery cell in battery pack to battery cell.
The first pulse-width signal PWM_LEFT that the first driver element 175 receiving processing modules 150 are exported is to control the whether conducting of the first path terminal in the first control switch 174 and alternate path end according to the first pulse-width signal PWM_LEFT; And the second pulse-width signal PWM_RIGHT that the second driver element 178 receiving processing modules 150 are exported is to control the whether conducting of the first path terminal in the second control switch 177 and alternate path end according to the second pulse-width signal PWM_RIGHT.
In the present embodiment, processing module 150 comprises the first pulse-width modulation (PWM) control unit 151 and the second pulse width modulation controlled unit 152.Wherein, the first pulse width modulation controlled unit 151 connects second voltage and electric current isolation collecting unit 162 isolates to receive second voltage and electric current the feedback signal that collecting unit was produced, and export the first pulse-width signal PWM_LEFT to the first driver element 175.The second pulse width modulation controlled unit 152 connects the feedback signal that the first voltage and current isolation collecting unit 161 is produced to receive the first voltage and current isolation collecting unit 161, and exports the second pulse-width signal PWM_RIGHT to the second driver element 178.Preferably, the first pulse width modulation controlled unit 151 and the second pulse width modulation controlled unit 152 can comprise respectively an independently pulse-width modulation (PWM) controller, and also can provide fixing reference voltage at the inner integrated two-way error amplifier of PDM keyer, described PDM keyer can adopt the PDM keyer of conventional TL594 model.In addition, the feedback signal that the first voltage and current isolation collecting unit 161 produces comprises voltage bias signal CUR_LEFT and voltage feedback signal VOLT_LEFT, accordingly, the feedback signal that second voltage and electric current isolation collecting unit 162 produce comprises voltage bias signal CUR_RIGHT and voltage feedback signal VOLT_RIGHT.
Preferably, two-way isolation DC-DC converter 100 of the present utility model also further comprises the first electromagnetic interference (electromagnetic interference, EMI) filter cell 181 and the second Electromagnetic interference filter unit 182.Wherein, the first Electromagnetic interference filter unit 181 is connected between the first port 110 and the first voltage and current isolation collecting unit 130, and the first voltage and current isolation collecting unit 130 connects the first port 110 by the first Electromagnetic interference filter unit 181; In like manner, the second Electromagnetic interference filter unit 182 is connected between the second port one 20 and second voltage and electric current isolation collecting unit 140, and second voltage is connected the second port one 20 with electric current isolation collecting unit 140 by the second Electromagnetic interference filter unit 182.The first Electromagnetic interference filter unit 181 and the second Electromagnetic interference filter unit 182 can adopt discrete common mode inductance, or the integrated device such as common mode inductance and differential mode inductance.
As shown in Figure 1, the primary structure symmetry of two-way isolation DC-DC variator 100 of the present utility model, for example the first Electromagnetic interference filter unit 181 and the second Electromagnetic interference filter unit 182 symmetries; The first filter circuit unit 161 and the second filter circuit unit 162 symmetries; The first voltage and current isolation collecting unit 130 and second voltage and electric current isolation collecting unit 140 symmetries; The first pulse width modulation controlled unit 151 in processing module 150 and the second pulse width modulation controlled unit 152 symmetries; The first absorptive unit 1701 in bi-directional power conversion module 170 and the second absorptive unit 1702 symmetries; The first driver element 175 and the second driver element 175 symmetries; The first left way switch 1721 in the first switches set 172 and the first right wing switch 1722 symmetries; The second left way switch 1731 in second switch group 173 and the second right wing switch 1732 symmetries; Etc..Therefore, very succinct of the circuit structure of two-way isolation DC-DC converter 100 of the present utility model.
The operation principle of two-way isolation DC-DC converter 100 of the present utility model will be introduced particularly below.
In the time carrying out the first voltage transformation, for example in the battery pack of series connection when the change in voltage between any one battery pack and accessory power supply, if the first port 110 is as input, and the second port one 20 is during as output, send energy from the first port 110 to the second port one 20, input terminal voltage V1 on the first port 110 is as input terminal voltage, and voltage V2 on the second port one 20 is as output end voltage, the high potential V1+ of the voltage V1 on the first port 110 is by the first Electromagnetic interference filter unit 181, the first voltage and current isolation collecting unit 130, the first filter circuit unit 161 and being applied on the port COM_LEFT of bi-directional power conversion module 170.
The first left side control signal LEFT_HIGH and the first right side control signal RIGHT_HIGH in first pair of control signal that processing module 150 is sent enable simultaneously, the first left side control signal LEFT_HIGH in the first control signal and the first right side control signal RIGHT_HIGH be simultaneously in low level state, the first left way switch 1721 in the first switches set 172 and the first right wing switch 1722 conductings simultaneously.And now, the second left side control signal LEFT_LOW in second pair of control signal that processing module 150 is sent and the second right side control signal RIGHT_LOW be disable simultaneously, the second left side control signal LEFT_LOW in second pair of control signal and the second right side control signal RIGHT_LOW are simultaneously in high level state, and the second left way switch 1731 in second switch group 173 and the second right wing switch 1732 are in off state.Therefore, at this moment, the first winding in transformer 171 is connected 171a, and it is in running order; And the second winding is to the non-connection of 171b, it is in non operating state.
Because the first port 110 is as input, and the second port one 20 is as output, therefore the first pulse width modulation controlled unit 151 sends the first pulse-width signal PWM_LEFT to the first driver element 175, and the second pulse width modulation controlled unit 152 does not send the second pulse-width signal PWM_RIGHT to the second driver element 178.
The first pulse-width signal PWM_LEFT that the first pulse width modulation controlled unit 151 sends inputs to the first driver element 175, the pulse-width signal that the first driver element 175 is exported homophase with drive the first control switch 174 with identical duty ratio turn-on and turn-off alternately.According to the principle of circuit of reversed excitation, in the time of the first control switch 174 conducting, the first winding is to the first left side winding 1711 stored energys in 171a, and the first diode 176 oppositely ends.Because the second pulse width modulation controlled unit 152 does not send the second pulse-width signal PWM_RIGHT to the second driver element 178, therefore the second driver element 178 and the second corresponding control switch 177 turn-off always.In the time that the first control switch 174 turn-offs, Energy Transfer to the first right side winding 1712 that the first left side winding 1711 in the first winding 171a is stored, and the first right wing switch 1722 of the first right side winding 1712, conducting, the second filter circuit unit 162, second voltage and electric current isolation collecting unit 140, the second Electromagnetic interference filter unit 182 and the second diode 179 form continuous current circuit, send energy thereby realize from the first port 110 to the second port one 20.
In this process, the first absorptive unit 1701 can be in the time that the first control switch 174 turn-offs, absorb transformer 171 due to the due to voltage spikes that leakage inductance produces, make the work that the first control switch 174 can safety, and simultaneously can avoid producing the problem of electromagnetic interference.
In addition, because the duty ratio of the first pulse-width signal PWM_LEFT that is input to the first driver element 175 is to be determined by the first pulse width modulation controlled unit 151 in processing module 150, and the first pulse width modulation controlled unit 151 is to connect second voltage and electric current isolation collecting unit 140 (it is connected the second port one 20), second voltage and electric current isolation collecting unit 140 obtains the electric current in voltage and the above-mentioned continuous current circuit at the second port one 20 places, input to the first pulse width modulation controlled unit 151 and compare with the setting threshold of the built-in two-way error amplifier in the first pulse width modulation controlled unit 151 respectively, in the time that it is greater than setting threshold, reduce the duty ratio of the first pulse-width signal PWM_LEFT, and in the time that it is less than setting threshold, increase the duty ratio of the first pulse-width signal PWM_LEFT, thereby by regulating the duty ratio of the first pulse-width signal PWM_LEFT, can realize the current constant in voltage constant and the above-mentioned continuous current circuit at the second port one 20 places.
Under the first voltage transformation pattern, if the first port 110 is as output, and the second port one 20 is as input, send energy from the second port one 20 to the first port 110, voltage V2 on the second port one 20 is as input terminal voltage, voltage V1 on the first port 110 is as output end voltage, the high potential V2+ of the input terminal voltage V2 on the second port one 20 is by the second Electromagnetic interference filter unit 182, second voltage and electric current isolation collecting unit 140, the second filter circuit unit 162 and being applied on the port COM_RIGHT of bi-directional power conversion module 170.
Similarly, two control signals in first pair of control signal that processing module 150 is sent enable simultaneously, two switches conducting simultaneously in the first switches set 172; And two control signals disable simultaneously in second pair of control signal, two switches in second switch group 172 are in off state.That is, at this moment, the first winding in transformer 171 is in running order to 171a, and the second winding to 171b in non operating state.
Because the second port one 20 is as input, and the first port 110 is as output, therefore the second pulse width modulation controlled unit 152 sends the second pulse-width signal PWM_RIGHT to the second driver element 178, and the first pulse width modulation controlled unit 151 does not send the first pulse-width signal PWM_LEFT to the first driver element 175.
The second driver element 178 receives the second pulse-width signal PWM_RIGHT, and the pulse-width signal of exporting homophase with drive the second control switch 177 with identical duty ratio turn-on and turn-off alternately.In the time of the second control switch 177 conducting, the first right side winding 1712 stored energys in the first winding 171a, the second diode 179 oppositely ends.The first driver element 175 and the first corresponding control switch 174 turn-off always.In the time that the second control switch 177 turn-offs, Energy Transfer to the first left side winding 1711 that the first right side winding 1712 in the first winding 171a is stored, and the first left way switch 1721, the first filter circuit unit 161, the first voltage and current isolation collecting unit 130, the first Electromagnetic interference filter unit 181 and first diode 176 of the first winding 1711, conducting form continuous current circuit, send energy thereby realize the second port one 20 to the first port 110.
Similarly, in this process, the second absorptive unit 1702 can be in the time that the second control switch 177 turn-offs, and absorbs transformer 171 due to the inductance spike that leakage inductance produces, and makes the second control switch 177 trouble free services, and avoids producing the problem of electromagnetic interference.
In addition, because the second pulse width modulation controlled unit 152 is to connect the first voltage and current isolation collecting unit 130 (it connects the first port 110), therefore by the first voltage and current isolation collecting unit 130, the voltage and current at the first port 110 places is gathered, the duty ratio of the second pulse-width signal PWM_RIGHT that exports the second driver element 178 to can be adjusted in the second pulse width modulation controlled unit 152, thereby realizes the current constant in voltage constant and the relevant continuous current circuit at the first port 110 places.
In the time carrying out the second voltage transformation, for example, while being cell in battery pack to change in voltage between battery cell, the similar process of itself and the first change in voltage, its difference is only, in the time carrying out the second voltage transformation, the first left side control signal LEFT_HIGH in first pair of control signal that processing module 150 is sent and the first right side control signal RIGHT_HIGH be disable simultaneously, and two switches in the first switches set 172 are turn-offed; And the second left side control signal LEFT_LOW and the second right side control signal RIGHT_LOW in second pair of control signal enable simultaneously, make two switch conductions in second switch group 173.That is to say, at this moment, the first winding in transformer 171 is to 171a in non operating state, and the second winding is in running order to 171b.
Refer to Fig. 2, it is the schematic diagram of the voltage and current isolation collecting unit shown in the utility model one embodiment.Wherein, the first voltage and current isolation collecting unit 130 shown in Fig. 1 and second voltage and electric current isolation collecting unit 140 all can adopt this structure, at this, are introduced particularly as an example of the first voltage and current isolation collecting unit 130 shown in Fig. 1 example.
As shown in Figure 2, voltage and current isolation collecting unit 200 comprises electric current isolation collecting unit 210 and voltage isolation collecting unit 220.Wherein, electric current isolation collecting unit 210 is for isolating the voltage bias signal CUR_LEFT that gathers and the current conversion gathering is become to isolation to the first port 110 shown in Fig. 1; And voltage is isolated collecting unit 220 for the voltage at the first port 110 places shown in Fig. 1 being isolated to collection, and the voltage transitions of collection is become to voltage feedback signal VOLT_LEFT.
Electric current isolation collecting unit 210 comprises the current sensor U1 based on Hall effect, for example common ACS712, electric current is changed into the voltage bias signal CUR_LEFT of isolation, wherein the electric current of the voltage amplitude of voltage bias signal CUR_LEFT and current flowing transducer U1 is linearly proportional.
Particularly, current sensor U1 comprises the first high voltage port IP+1, the second high voltage port IP+2, the first low-voltage port IP-1, the second low-voltage port IP-2, power port VCC, output port VIOUT, filtering port FILTER and grounding ports GND.Wherein, the first high voltage port IP+1 and the second high voltage port IP+2 link together, and isolate a port of collecting unit 200 as electric current, receive the first collection voltage IP1+ and (that is to say, as shown in Figure 1, be connected to the first filter circuit unit 130).The first low-voltage port IP-1 and the second low-voltage port IP-2 link together, and as a port of electric current isolation collecting unit 200, receive second and gather voltage IP1-(that is to say, as shown in Figure 1, be connected to the first Electromagnetic interference filter unit 181).Grounding ports GND ground connection, filtering port FILTER is connected to grounding ports GND by capacitor C 1, and voltage port VCC is connected to the first power supply VCC1, for example+5V, and be connected to grounding ports GND by capacitor C 2, and output port VIOUT is for output voltage offset signal CUR_LEFT.
In the time not having electric current to flow through from the path of the first collection voltage IP1+ to the second collection voltage IP1-, voltage bias signal CUR_LEFT is a fixing bias voltage, represents that the electric current flowing through is 0; In the time that electric current flows to the second collection voltage IP1-place from the first collection voltage IP1+, the voltage of voltage bias signal CUR_LEFT is greater than fixing bias voltage; In the time that electric current flows to the first collection voltage IP1+ place from the second collection voltage IP1-, the voltage of voltage bias signal CUR_LEFT is less than fixing bias voltage.
Voltage isolation collecting unit 220 comprises the first light coupling relay 221, the second light coupling relay 222, programmable a reference source 223 and the 3rd light coupling relay 224.
Wherein, the first light coupling relay 221 comprises light-emitting component 2211 and optical coupled switch 2212, and one end of light-emitting component 2211 is connected to the first voltage VCC1 by the first resistance R 1, and its other end receives the 3rd control signal LEFT_VFB1; The control end of optical coupled switch 2212 and light-emitting component 2211 are coupled, one path terminal is connected to the first collection voltage, and another path terminal is by the second resistance R 2 and the 3rd resistance R 3 ground connection, wherein, described another path terminal is as first node A, and junction between the second resistance R 2 and the 3rd resistance R 3 is as Section Point B.
The second light coupling relay 222 comprises light-emitting component 2221 and optical coupled switch 2222, and one end of light-emitting component 2221 is connected to the first power supply VCC1 by the 4th resistance R 4, and its other end receives the 4th control signal LEFT_VFB2; The control end of optical coupled switch 2222 and light-emitting component 2221 are coupled, and one path terminal is connected to Section Point B, and another path terminal is by the 5th resistance R 5 ground connection.
Programmable a reference source 223 can adopt common TL431 chip, and its one end is connected to first node A by the 6th resistance R 6, and other end ground connection, and its control end is connected to Section Point B.
The 3rd light coupling relay 224 comprises light-emitting component 2241 and optical coupled switch 2242, and one end of light-emitting component 2241 is connected to first node A by the 7th resistance R 7, and the other end is connected to the junction between the 6th resistance R 6 and programmable a reference source 223; The control end of optical coupled switch 2242 and light-emitting component 2241 are coupled, and one path terminal is connected to by the 8th resistance R 8 the fixed reference voltage REF_LEFT (referring to subsequent descriptions) that shown in Fig. 1, the first pulse width modulation controlled unit 151 produces, and its another path terminal is passed through the 9th resistance R 9 ground connection, and the output that described another path terminal is isolated collecting unit 200 as voltage is with output voltage feedback signal VOLT_LEFT.
Wherein, the programming device in the 3rd control signal LEFT_VFB1 and the 4th control signal LEFT_VFB2 processing module 150 as shown in Figure 1, the such as device such as MCU or CPLD control output.
In the time that the 3rd control signal LEFT_VFB1 is high level, the light-emitting component 2211 in the first light coupling relay 221 is not luminous, and optical coupled switch 2212 ends, and the first light coupling relay 221 is ended.Because the first light coupling relay 221 is ended, therefore the light-emitting component 2241 in the 3rd light coupling relay 224 is not luminous, and optical coupled switch 2242 ends, and the 3rd light coupling relay 224 is ended equally.
When the 3rd control signal LEFT_VFB1 is low level and the 4th control signal LEFT_VFB2 while being high level, the first light coupling relay 221 conductings, and the second light coupling relay 222 is ended.When after the first light coupling relay 221 conductings, the first collection voltage IP1+ powers to programmable a reference source 223 by the optical coupled switch 2212 in the first light coupling relay 221 of conducting and the 6th resistance R 6, in addition, due to optical coupled switch 2212 conductings in the first light coupling relay 221, the second resistance R 2 and the 3rd resistance R 3 are connected between the first collection voltage IP1+ and ground and carry out dividing potential drop, and the branch pressure voltage at Section Point B place inputs to the control end of programmable a reference source 223.Owing to being integrated with voltage error comparator in programmable a reference source 223, therefore in the time that the branch pressure voltage at Section Point B place is less than its compare threshold, programmable a reference source 223 conductings, the voltage of the junction of the light-emitting component 2241 of itself and the 6th resistance R 6 and the 3rd optical coupled switch 224 is pulled low to ground, the voltage at first node A place is by the 7th resistance R 7, discharge in the light-emitting component 2241 of the 3rd optical coupled switch 224 and programmable a reference source 223 loop that forms of conducting, therefore the light-emitting component 2241 of the 3rd optical coupled switch 224 is luminous, and optical coupled switch 2242 conductings, i.e. the 3rd optical coupled switch 224 conductings, therefore power supply feedback signal VOLT_LEFT is pulled to high level by the 8th resistance R 8.And in the time that the branch pressure voltage at Section Point B place is greater than its compare threshold, programmable a reference source 223 is turn-offed, therefore the programmable a reference source 223 of the light-emitting component 2241 of the 7th resistance R 7, the 3rd optical coupled switch 224 and shutoff can not form loop, light-emitting component 2241 can not be luminous, optical coupled switch 2242 ends, the 3rd optical coupled switch 224 ends, and therefore power supply feedback signal VOLT_LEFT is pulled down to low level by the 9th resistance R 9.After said process balance, it is stable that the voltage at first node A place keeps, and the first voltage that gathers voltage IP1+ place keeps stable.
In said process, in the time that the 4th control signal LEFT_VFB2 is also low level, the second light coupling relay 220 conductings, therefore the 5th resistance R 5 is in parallel with the 3rd resistance R 3, it changes the partial pressure value at Section Point B place, thereby can realize the stable voltage that changes first node A place, change the stable voltage at the first collection voltage IP1+ place.
In addition, it will be understood by those skilled in the art that, the above-mentioned introduction about voltage and current isolation collecting unit 200 is to be specifically introduced as an example of the first voltage and current isolation collecting unit 130 shown in Fig. 1 example, but the second voltage shown in Fig. 1 and electric current isolation collecting unit 140 also have identical structure and operation principle, only need be by relevant signal and the corresponding change of annexation.
Refer to Fig. 3, it is the schematic diagram of the pulse width modulation controlled unit shown in the utility model one embodiment.Wherein, the first pulse width modulation controlled unit 151 shown in Fig. 1 and the second pulse width modulation controlled unit 152 all can adopt this structure, at this, are introduced particularly as an example of the second pulse width modulation controlled unit 152 shown in Fig. 1 example.
As shown in Figure 3, pulse width modulation controlled of the present utility model unit 300 mainly comprises PDM keyer U13, and it is integrated two-way error amplifier also can provide fixed reference voltage REF_LEFT, for example common TL594 chip.
Particularly, PDM keyer U13 comprises 16 ports, i.e. port one IN+, port one IN-, port 2IN+, port 2IN-, port FB, port DTC, port CT, port RT, port GND, port C1, port REF, port O.C, port VCC, port C2, port E2, port E1.
Wherein, fixed reference voltage REF_LEFT is by resistance R 31 and the rear ground connection of resistance R 32, and junction between resistance R 31 and resistance R 32 is defined as node C.
Port one IN+ receives above-mentioned voltage feedback signal VOLT_LEFT, and port 2IN+ is by the rear receiver voltage offset signal of resistance R 33 CUR_LEFT, port one IN-connected node C.The loop that port FB contact resistance R34, resistance R 35 and capacitor C 31 form, and the further connectivity port 1IN-of node between resistance R 34 and resistance R 35.Port DTC ground connection.Port CT is by the rear ground connection of capacitor C 32.Port RT is by the rear ground connection of resistance R 36.Port GND ground connection.Port C1 connects second source VCC2, and second source VCC2 is by the rear ground connection of capacitor C 33.Port 2IN-is connected to a path terminal of transistor Q1 by resistance R 37, the control end of transistor Q1 receives a control signal LEFT_CFB, wherein, the programming device of control signal LEFT_CFB in can processing module 150 as shown in Figure 1, the such as device such as MCU or CPLD control output.And another path terminal ground connection of transistor Q1.Port REF output fixed reference voltage REF_LEFT, and by resistance R 38a and another path terminal the ground connection that are connected transistor Q1 after resistance R 38b.Port O.C ground connection.Port VCC and port C2 link together, and connect second source VCC2.Port E2 and port E1 link together and pass through resistance R 39 ground connection, and port E2 and port E2 are for output pulse width modulation signal PWM_RIGHT.
The fixed reference voltage that fixed reference voltage REF_LEFT produces for PDM keyer U13, and it carries out dividing potential drop through resistance R 31, resistance R 32, resistance R 43 and resistance R 51, thereby respectively as the voltage error comparator of PDM keyer U13 inside and the compare threshold of current error comparator.
In the time that control signal LEFT_CFB is high level, transistor Q1 conducting.After transistor Q1 conducting, resistance R 37 is in parallel with resistance R 38b, change the compare threshold of current error comparator, thereby change the stationary value of voltage bias signal CUR_LEFT, change first shown in Fig. 2 gather between voltage IP1+ and the second collection voltage IP1-stable electrical flow valuve.
In addition, it will be understood by those skilled in the art that, the above-mentioned introduction about pulse width modulation controlled unit 300 is to be specifically introduced as an example of the second pulse width modulation controlled unit 152 shown in Fig. 1 example, but the first pulse width modulation controlled unit 151 shown in Fig. 1 also has identical structure and operation principle, only need change corresponding relevant signal.
Refer to Fig. 4, it is the schematic diagram of the switch in switch and the second switch group in the first switches set shown in the utility model one embodiment.Wherein, the first left way switch 1721 in the first switches set 172 shown in Fig. 1 and the first right wing switch 1722 all can adopt the structure of the first switch 410 shown in Fig. 4, and the second left way switch 1731 in the second switch group 173 shown in Fig. 1 and the second right wing switch 1732 all can adopt the structure of the second switch 420 shown in Fig. 4.At this, be introduced particularly as an example of the first left way switch 1721 shown in Fig. 1 and the second left way switch 1731 example.
As shown in Figure 4, the first switch 410 comprises the 4th light coupling relay 411 and switch element 412.Wherein, the 4th light coupling relay 411 comprises light-emitting component 4111 and optical coupled switch 4112, one end of light-emitting component 4111 is connected to the first power supply VCC1 by the 11 resistance R 11, and its other end receives the corresponding control signal in first pair of control signal, at this, be the first left side control signal LEFT_HIGH.The control end of optical coupled switch 4112 and light-emitting component 4111 are coupled, one path terminal ground connection, and another path terminal is connected to the first filter circuit unit 130 by the rear port as the bi-directional power conversion module shown in Fig. 1 of the 12 resistance R the 12 and the 13 resistance R 13, i.e. COM_LEFT node in Fig. 1.The control end of switch element 412 is connected to the node D between the 12 resistance R the 12 and the 13 resistance R 13, one path terminal is connected to the first filter circuit unit 130 shown in Fig. 1, it is COM_LEFT node in Fig. 1, and the one end to the first left side winding 1711 in 171a of the first winding shown in its another path terminal connection layout 1, i.e. S1A node shown in Fig. 1.
In the time that the first left side control signal LEFT_HIGH is low level, the light-emitting component 4111 in the 4th light coupling relay 411 is luminous, optical coupled switch 4112 conductings, i.e. the 4th light coupling relay 411 conductings.Now, the loop that the voltage at node COM_LEFT place forms through the optical coupled switch 4112 of the 13 resistance R the 13, the 12 resistance R 12 and conducting, the 13 resistance R the 13 and the 12 resistance R 12 is carried out after dividing potential drop, the branch pressure voltage at node D place is greater than the threshold voltage of switch element 412, therefore switch element 412 conductings, the voltage at node COM_LEFT place passes through the switch element 412 of conducting and is passed to node S1A node, passes to the first winding to the first left side winding 1711 in 171a.
And in the time that the first left side control signal LEFT_HIGH is high level, the light-emitting component 4111 in the 4th light coupling relay 411 is not luminous, optical coupled switch 4112 ends, and the 4th light coupling relay 411 is ended.Therefore, the optical coupled switch 4112 of the 13 resistance R the 13, the 12 resistance R 12 and cut-off can not form loop, and the voltage at node D place is lower than the threshold voltage of switch element 412, and therefore switch element 412 ends.
Second switch 420 comprises relay 421 and switch element 422.Wherein, relay 421 is connected to the first filter circuit unit 130 shown in Fig. 1 (being the node COM_LEFT shown in Fig. 1) and the second winding between the second left side winding 1715 in 171b (being the node S2A shown in Fig. 1).The control end of switch element 422 receives the corresponding control signal in second pair of control signal, at this, is the second left side control signal LEFT_LOW, and one path terminal ground connection, and another path terminal is connected to relay 421.
In the time that the second left side control signal LEFT_LOW is high level, switch element 422 conductings, therefore it makes relay 421 adhesives, and node COM_LEFT communicates with node S2A, and node COM_LEFT transfers to node S2A.In the time that the second left side control signal LEFT_LOW is low level, switch element 422 ends, thereby makes relay 421 disconnect, and node COM_LEFT communicates with node S2A is non-.
In addition, it will be understood by those skilled in the art that, the above-mentioned introduction about the first switch 410 and second switch 420 is to be introduced as an example of the first left way switch 1721 shown in Fig. 1 and the second left way switch 1731 example, but the first right wing switch 1722 shown in Fig. 1 and the second right wing switch 1732 also have the operation principle of identical mechanism, only need be by relevant signal and the corresponding change of annexation.
In sum, the structural design of two-way isolation DC-DC isolator 100 of the present utility model has symmetry, structure is very succinct and ingenious, and its compatibility the voltage transformation between change in voltage or high-tension battery group and accessory power supply between the high-tension battery group group of the voltage transformation between battery unit and series connection in high-tension battery group group, its application is more extensive.Separately, two-way isolation DC-DC isolator 100 of the present utility model can be realized constant voltage and the constant current control of both sides, and can be as required, automatically change constant voltage value and constant current value, practicality is stronger, and its not only input and output isolation, and relevant collecting unit and control unit are also isolated, antijamming capability is stronger, and reliability is higher, has improved electromagnetic compatibility characteristic.
The foregoing is only execution mode of the present utility model; not thereby limit the scope of the claims of the present utility model; every equivalent structure or conversion of equivalent flow process that utilizes the utility model specification and accompanying drawing content to do; or be directly or indirectly used in other relevant technical fields, be all in like manner included in scope of patent protection of the present utility model.