Power distribution unit, power distribution module, and electronic device

Abstract

The utility model discloses a power distribution unit, a power distribution module and electronic equipment. The pre-charging main circuit comprises a power resistor and a first switching tube, the first end of the first switching tube is connected with the power supply port through the power resistor, the second end of the first switching tube is connected with the power distribution port, and the third end of the first switching tube is connected with the control port; each pre-charging branch comprises a second switch tube, the first end of the second switch tube is connected with the power supply port, the second end of the second switch tube is connected with the power distribution port, and the third end of the second switch tube is connected with the control port; and the control port is used for receiving the first control signal and the at least one second control signal which are input in sequence, so that the pre-charging main circuit and the at least one pre-charging branch circuit are subjected to pre-charging operation in sequence. According to the scheme, time-sharing multi-point through-flow heat dissipation can be realized, and the through-flow heat dissipation pressure and the through-flow heat dissipation limit of the power distribution unit can be reduced, so that the through-flow heat dissipation requirement is met.

Description

TECHNICAL FIELD

[0001] The utility model relates to electronic technical field especially relates to a distribution unit, distribution module and electronic equipment. BACKGROUND

[0002] The present running various high -power electric appliances, whether it is DC electric appliance or AC electric appliance, generally needs to set up distribution unit between power supply and load element, the load element here includes but is not limited to the bus capacitor connected with distribution unit through power bus, at the power -on instant, bus capacitor is regarded as short circuit to ground, its process will produce greater inrush current, leads to power bus and distribution unit to bear greater stress, and further causes overcurrent protection action, device overheat even damage etc. problem, therefore, need to set up precharge circuit in distribution unit.

[0003] The existing precharge circuit generally includes seriesly arranged power resistor and control switch, and the precharge circuit is at the charging start instant, current flow and heat dissipation are concentrated on power resistor, that is, the existing precharge circuit is single time single point flow and heat dissipation, and cannot satisfy the flow and heat dissipation demand. SUMMARY

[0004] The utility model discloses a distribution unit, distribution module and electronic equipment to solve the problem that the existing precharge circuit cannot satisfy the flow and heat dissipation demand.

[0005] A distribution unit, including power supply port, distribution port and control port, the distribution unit still includes precharge main road and at least one precharge branch:

[0006] The precharge main road includes power resistor and first switch tube, and the first end of the first switch tube is connected with the power supply port through the power resistor, the second end of the first switch tube is connected with the distribution port, and the third end of the first switch tube is connected with the control port;

[0007] Each precharge branch includes a second switch tube, the first end of the second switch tube is connected with the power supply port, the second end of the second switch tube is connected with the distribution port, and the third end of the second switch tube is connected with the control port;

[0008] The control port is used to receive the first control signal and at least one second control signal input in turn;The first control signal is used for controlling the first switch tube to be in the on state all the time in the precharge stage, so that the precharge main road carries out precharge operation;Each second control signal is used for controlling a second switch tube to be in the on state all the time in the precharge stage, so that the precharge branch corresponding to the second switch tube carries out precharge operation.

[0009] Preferably, the first switch tube is an NMOS tube or a PMOS tube; and the second switch tube is a PMOS tube.

[0010] Preferably, the first switch tube is an NMOS tube, and the pre-charge main path further comprises 2N driving circuits, the 2N driving circuits being connected in series between the control port and a third terminal of the first switch tube, and used for performing even times of phase conversion on the first control signal to drive the NMOS tube to work.

[0011] Alternatively, the first switch tube is a PMOS tube, and the pre-charge main path further comprises 2N-1 driving circuits, the 2N-1 driving circuits being connected in series between the control port and a third terminal of the first switch tube, and used for performing odd times of phase conversion on the first control signal to drive the PMOS tube to work; wherein N≥1.

[0012] Preferably, the pre-charge main path further comprises a first driving circuit and a second driving circuit.

[0013] The first driving circuit comprises a first load resistor and a bias circuit, the first load resistor and the bias circuit being connected in series between the power supply port and the ground, and the bias circuit being further connected to the control port.

[0014] The second driving circuit comprises a third switch tube and a second load resistor, a first terminal of the third switch tube being connected to the power supply port, a second terminal of the third switch tube being connected to the ground through the second load resistor, and a third terminal of the third switch tube being connected to a connection node between the first load resistor and the bias circuit.

[0015] A third terminal of the first switch tube is connected to a connection node between the third switch tube and the second load resistor.

[0016] Preferably, the bias circuit comprises a first triode, a first bias resistor and a second bias resistor.

[0017] The first bias resistor and the second bias resistor are connected in series between the control port and the ground.

[0018] A first terminal of the first triode is connected to the first load resistor and the third switch tube, a second terminal of the first triode is connected to the ground, and a third terminal of the first triode is connected to a connection node between the first bias resistor and the second bias resistor.

[0019] Preferably, the pre-charge branch further comprises a current source and a soft start circuit.

[0020] The first end of the current source is connected with the control port, and the second end of the current source is connected with the soft start circuit, for outputting a soft start current to the soft start circuit based on the second control signal;

[0021] The first end of the soft start circuit is connected with the power supply port, and the second end of the soft start circuit is connected with the third end of the second switch tube and the current source, for outputting a soft start voltage to the second switch tube based on the soft start current, so that the second switch tube is always in a conducting state in the pre-charging stage.

[0022] Preferably, the current source comprises a second triode, a third bias resistor, a fourth bias resistor and a third load resistor;

[0023] The third bias resistor and the fourth bias resistor are connected in series between the control port and the ground;

[0024] The first end of the second triode is connected with the second end of the soft start circuit, the second end of the second triode is grounded through the third load resistor, and the third end of the second triode is connected with a connection node between the third bias resistor and the fourth bias resistor.

[0025] Preferably, the soft start circuit comprises a soft start circuit, a first diode and a pull-up resistor;

[0026] The pull-up resistor and the current source are connected in series between the power supply port and the ground;

[0027] The first end of the soft start circuit is connected with the power supply port, and the second end of the soft start circuit is connected with the anode of the first diode, and the cathode of the first diode is connected with the third end of the second switch tube;

[0028] The cathode of the first diode is also connected with a connection node between the pull-up resistor and the current source, for outputting a soft start voltage to the second switch tube based on the soft start current output by the current source, so as to control the second switch tube to be always in a conducting state in the pre-charging stage.

[0029] Preferably, the soft start circuit comprises a soft start resistor and a soft start capacitor connected in parallel.

[0030] Preferably, the pre-charging branch further comprises a pressure-sensitive gating circuit;

[0031] The first end of the pressure-sensitive gating circuit is connected with the third end of the second triode, and the second end of the pressure-sensitive gating circuit is connected with the power distribution port.

[0032] Preferably, the voltage-sensitive gating circuit comprises a second diode, an anode of the second diode being connected to the third terminal of the second transistor, and a cathode of the second diode being connected to the power distribution port.

[0033] Alternatively, the voltage-sensitive gating circuit comprises at least two second diodes connected in series, an anode of a first second diode being connected to the third terminal of the second transistor, and a cathode of a last second diode being connected to the power distribution port.

[0034] A power distribution module comprises a control unit and the power distribution unit.

[0035] The control unit is connected to the control port and is configured to output a first control signal and at least one second control signal to the control port in sequence.

[0036] Preferably, the control unit is configured to output a first control signal to the first switch tube at the moment when the power distribution unit is powered on, so as to control the first switch tube to be in a conductive state all the time in the pre-charging stage, so that the pre-charging main branch performs pre-charging operation and obtains the power distribution voltage corresponding to the control port.

[0037] When the power distribution voltage reaches a turn-on voltage corresponding to any of the pre-charging branches, a second control signal is output to the second switch tube of the pre-charging branch that reaches the turn-on voltage, so as to control the second switch tube to be in a conductive state all the time in the pre-charging stage, so that the pre-charging branch corresponding to the second switch tube performs pre-charging operation.

[0038] An electronic device comprises a power supply, a power bus, a bus capacitor, and the power distribution module.

[0039] The power supply is connected to the power supply port of the power distribution unit.

[0040] The bus capacitor is connected to the power distribution port of the power distribution unit through the power bus.

[0041] The power distribution unit, the power distribution module, and the electronic device have the pre-charging main branch and the at least one pre-charging branch connected in parallel between the power supply port and the power distribution port, so that the pre-charging main branch and the at least one pre-charging branch can be turned on in time according to the first control signal and the at least one second control signal input to the control port in sequence, so that the power distribution unit can realize time-sharing multi-point current flow heat dissipation, which helps to reduce the current flow heat dissipation pressure and the current flow heat dissipation capacity of the power distribution unit, so as to meet the current flow heat dissipation demand. BRIEF DESCRIPTION OF DRAWINGS

[0042] In order to more clearly illustrate the technical scheme of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the description of the embodiments of the present application. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0043] Figure 1 is a circuit schematic diagram of a power distribution unit in an embodiment of the present application;

[0044] Figure 2 is Figure 1 the operation mode of the power distribution unit shown in the figure is compared with the operation mode of the power distribution unit in the prior art, Figure 2 A, Figure 2 B and Figure 2 C are respectively the comparison diagrams of the current I, voltage V and heat dissipation W of two power distribution units changing with time, Figure 2 D is used to reflect the comparison diagram of the conduction time and conduction voltage of the pre-charging main path and two pre-charging branch paths.

[0045] Figure 3 is the working envelope waveform of the soft start circuit in an embodiment of the present application, Figure 3 A is the working envelope waveform of the level signal with a duty ratio of 100, Figure 3 B is the working envelope waveform of the PWM signal with a duty ratio of 40%, Figure 3 C is the working envelope waveform of the PWM signal with a duty ratio of 20%.

[0046] Figure 4 is a circuit schematic diagram of an electronic device in an embodiment of the present application;

[0047] Figure 5 is a flow chart of the simulation design method of the power distribution unit in an embodiment of the present application;

[0048] Figure 6 is a circuit schematic diagram of a prototype circuit in an embodiment of the present application;

[0049] Figure 7 is a schematic diagram of the simulation result of the pre-charging main path in an embodiment of the present application;

[0050] Figure 8 is a specific circuit diagram of the power distribution unit in an embodiment of the present application;

[0051] Figure 9 is Figure 8 the application example simulation result of the power distribution unit shown in the figure;

[0052] Figure 10 is Figure 8Simulation results of the power distribution unit shown for different control signals.

[0053] Figure 11 is Figure 8 Simulation results of the power distribution unit shown and the RC pre-charge circuit of the prior art.

[0054] In the figure: 1, power distribution unit; Vi, power supply port; Vo, power distribution port; Vc, control port; 11, pre-charge main path; Rpow, power resistor; M1, first switch tube; 111, first drive circuit; Rn3, first load resistor; 1111, bias circuit; Q1, first triode; Rn1, first bias resistor; Rn2, second bias resistor; 112, second drive circuit; M3, third switch tube; Rn4, second load resistor; 12, pre-charge branch; M2, second switch tube; 121, current source; Q2, second triode; Rp1, third bias resistor; Rp2, fourth bias resistor; Rpc, third load resistor; 122, soft start circuit; 1221, slow start circuit; Rp4, slow start resistor; Cp1, slow start capacitor; Dp1, first diode; Rp3, pull-up resistor; 123, pressure-sensitive gating circuit; Dp2, second diode; 2, control unit; 3, power supply; 4, power bus; 5, bus capacitor. DETAILED DESCRIPTION

[0055] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0056] The embodiment of the present application provides a power distribution unit 1, which is arranged between a power supply 3 and a load element. The load element includes, but is not limited to, a bus capacitor 5 connected to the power distribution unit 1 through a power bus 4.

[0057] The embodiment of the present application provides a power distribution unit 1, which is arranged between a power supply 3 and a load element. The load element includes, but is not limited to, a bus capacitor 5 connected to the power distribution unit 1 through a power bus 4. Figure 1As shown, the power distribution unit 1 includes a power supply port Vi, a power distribution port Vo and a control port Vc, and further includes a pre-charge main path 11 and at least one pre-charge branch path 12. The pre-charge main path 11 includes a power resistor Rpow and a first switch tube M1, the first end of the first switch tube M1 is connected to the power supply port Vi through the power resistor Rpow, the second end of the first switch tube M1 is connected to the power distribution port Vo, and the third end of the first switch tube M1 is connected to the control port Vc. Each pre-charge branch path 12 includes a second switch tube M2, the first end of the second switch tube M2 is connected to the power supply port Vi, the second end of the second switch tube M2 is connected to the power distribution port Vo, and the third end of the second switch tube M2 is connected to the control port Vc. The control port Vc is used to receive a first control signal and at least one second control signal input in sequence. The first control signal is used to control the first switch tube M1 to be always in a conduction state in the pre-charge stage, so that the pre-charge main path 11 performs pre-charge operation. Each second control signal is used to control a second switch tube M2 to be always in a conduction state in the pre-charge stage, so that the corresponding pre-charge branch path 12 performs pre-charge operation.

[0058] The first control signal is a control signal used to control the first switch tube M1 to be always in a conduction state in the pre-charge stage, so that the pre-charge main path 11 performs pre-charge operation in the pre-charge stage. The second control signal is a control signal used to control the second switch tube M2 to be always in a conduction state in the pre-charge stage, so that the corresponding pre-charge branch path 12 performs pre-charge operation in the pre-charge stage.

[0059] The power supply port Vi is a port used to connect a power supply 3, the power distribution port Vo is a port used to connect a load element, and the control port Vc is a port used to connect a control unit 2 to receive a control signal input by the control unit 2.

[0060] As an example, the power distribution unit 1 includes the pre-charge main path 11 and at least one pre-charge branch path 12, and the number of the at least one pre-charge branch path 12 can be determined autonomously according to actual conditions. In this example, the pre-charge main path 11 and the at least one pre-charge branch path 12 are arranged in parallel between the power supply port Vi and the power distribution port Vo, and are both connected to the control port Vc. The pre-charge main path 11 and the at least one pre-charge branch path 12 can be controlled to work in time division according to the control signal input by the control port Vc, so as to avoid damage to components in the circuit caused by a large inrush current generated at the power-on moment of the power distribution unit 1.

[0061] In this example, the pre-charge main circuit 11 includes a power resistor Rpow and a first switch tube M1 connected in series, that is, the first end of the first switch tube M1 is connected to the power supply port Vi through the power resistor Rpow, and the power supply port Vi is used to connect the power supply 3, which can be a power supply for charging the bus capacitor 5 during the pre-charge process, including but not limited to a battery arranged in the electronic device; the second end of the first switch tube M1 is connected to the power distribution port Vo, and the power distribution unit 1 is connected to the bus capacitor 5 or other load elements; the third end of the first switch tube M1 is connected to the control port Vc, and the first control signal input based on the control port Vc is always in a conductive state in the pre-charge stage. When the first switch tube M1 is always in a conductive state in the pre-charge stage, the on-resistance of the first switch tube M1 can be almost negligible compared to the resistance value of the power resistor Rpow. During the charging process of the pre-charge main circuit 11, the bus capacitor 5 discharges through the power resistor Rpow, and the capacitor voltage of the bus capacitor 5 changes with time according to the RC charging curve corresponding to the pre-charge main circuit 11. After charging for 3 RC constants, the capacitor voltage of the bus capacitor 5 rises to 95% of the power supply voltage Vs, and after charging for 5 RC constants, the capacitor voltage of the bus capacitor 5 rises to 99.3% of the power supply voltage Vs.

[0062] The RC charging curve can be shown in the following formula (1);

[0063] Vc(t)=Vs*[1-e (-t / RC) ] ……(1)

[0064] The working process of the pre-charge main circuit 11, the charge is transferred from the power supply 3 to the bus capacitor 5 through the power distribution unit 1 to charge the bus capacitor 5. The charge flows through the power resistor Rpow, and the related parameters are shown in the following formula (2):

[0065] Q=C*Vs=I*Trc,R=Trc / C,E=C*Vs 2 / 2,Ppk=Vs 2 / R ……(2)

[0066] Wherein, Q is the charging charge amount in the power-on process, C is the capacitance value of the power bus 4 to the ground, Vs is the power supply voltage, I is the charging current, R is the resistance value of the power resistor Rpow, Trc is the RC charging time, E is the energy transfer work and heat in the power-on process, and Ppk is the peak heat power of the power resistor Rpow.

[0067] In the example, the pre-charge branch 12 includes a second switch tube M2, a first end of the second switch tube M2 is connected with a power supply port Vi, and the power supply port Vi is used for connecting a power supply 3; a second end of the second switch tube M2 is connected with a distribution port Vo, and the distribution port Vo of the distribution unit 1 is connected with a bus capacitor 5 or other load elements through a power bus 4; a third end of the second switch tube M2 is connected with a control port Vc, and the second switch tube M2 can be always in a conduction state in the pre-charge stage based on a second control signal input by the control port Vc; when the second switch tube M2 is always in the conduction state in the pre-charge stage, the bus capacitor 5 is discharged through a conduction resistance of the second switch tube M2, at this time, a capacitor voltage of the bus capacitor 5 changes with time according to an RC charging curve (see formula (1) described above) corresponding to the pre-charge branch 12, and because a resistance value of the conduction resistance of the second switch tube M2 is much smaller than a resistance value of the power resistor Rpow, conduction voltages of the pre-charge main branch 11 and the at least one pre-charge branch 12 are different, and then RC charging curves and charging delays between the pre-charge main branch 11 and the at least one pre-charge branch 12 are completely different.

[0068] In the example, the first switch tube M1 and the at least one second switch tube M2 in the distribution unit 1 can receive a first control signal and at least one second control signal input by the control port Vc in sequence, the first control signal received first can control the first switch tube M1 to be always in a conduction state in the pre-charge stage, so that the pre-charge main branch 11 performs a pre-charge operation; during the pre-charge operation of the pre-charge main branch 11, the second control signal received later can control the second switch tube M2 in one pre-charge branch 12 to be always in a conduction state in the pre-charge stage, so that the pre-charge branch 12 performs a pre-charge operation, so that the first switch tube M1 and the at least one second switch tube M2 are controlled to be in a conduction state in time based on the control signal, thereby making the pre-charge main branch 11 and the at least one pre-charge branch 12 perform pre-charge operations in time.

[0069] As Figure 2As shown, when the number of pre-charging branches 12 is 2, the pre-charging process of the power distribution unit 1 is divided into three pre-charging stages, namely, a pre-charging initial stage, a pre-charging middle stage and a pre-charging final stage. In the pre-charging initial stage (i.e., the 0-Ta stage), based on the first control signal input by the control port Vc, the first switch tube M1 of the pre-charging main branch 11 is controlled to be in a conductive state throughout the pre-charging stage. At this time, only the pre-charging main branch 11 is started, so that the power supply 3 charges the bus capacitor 5 through the pre-charging main branch 11, and the capacitor voltage of the bus capacitor 5 is charged from 0V to Va. In the pre-charging middle stage (i.e., the Ta-Tb stage), based on the first second control signal input by the control port Vc, the second switch tube M2 of the first pre-charging branch 12 is controlled to be in a conductive state throughout the pre-charging stage, so that the pre-charging main branch 11 and the first pre-charging branch 12 are started, so that the power supply 3 charges the bus capacitor 5 through the pre-charging main branch 11 and the pre-charging branch 12, and the capacitor voltage of the bus capacitor 5 is charged from Va to Vb. In the pre-charging final stage (i.e., after Tb), based on the second second control signal input by the control port Vc, the second switch tube M2 of the second pre-charging branch 12 is controlled to be in a conductive state throughout the pre-charging stage, so that the pre-charging main branch 11 and the two pre-charging branches 12 are started, so that the power supply 3 charges the bus capacitor 5 through the pre-charging main branch 11 and the two pre-charging branches 12.

[0070] In this example, the pre-charging main branch 11 and at least one pre-charging branch 12 are arranged in parallel between the power supply port Vi and the power distribution port Vo, so that the pre-charging main branch 11 and at least one pre-charging branch 12 can be time-sharing conductive according to the first control signal and at least one second control signal input by the control port Vc in sequence, so that the power distribution unit 1 can realize time-sharing multi-point through-flow heat dissipation, which helps to reduce the through-flow heat dissipation pressure and the through-flow heat dissipation capacity of the power distribution unit 1 to meet the through-flow heat dissipation demand.

[0071] In an embodiment, the control signal is a level signal or a PWM signal.

[0072] As an example, the control signal (including the first control signal and the second control signal) input by the control port Vc can be a level signal or a PWM signal with a fixed duty cycle, without the need for closed-loop control of the control unit, i.e., without the need for closed-loop control of the MCU. In this example, when a level signal is used as the control signal, the charging time is significantly shortened compared to the RC scheme; when a PWM signal is used as the control signal, the duty cycle can be set as needed, which extends the charging time while reducing the through-flow heat dissipation capacity requirement of the device. The smaller the duty cycle, the longer the charging time, and the lower the through-flow heat dissipation capacity requirement.

[0073] In an embodiment, the first switch tube M1 is an NMOS tube or a PMOS tube; the second switch tube M2 is a PMOS tube.

[0074] As an example, the first switch tube M1 can be an NMOS tube or a PMOS tube, which can be determined autonomously according to actual conditions. Generally, under the same current specification, the NMOS tube is lower in cost than the PMOS tube, and therefore, the first switch tube M1 in the pre-charge main path 11 is preferably an NMOS tube. When the first switch tube M1 is an NMOS tube, the first end of the first switch tube M1 is the drain of the NMOS tube, the second end of the first switch tube M1 is the source of the NMOS tube, and the third end of the first switch tube M1 is the gate of the NMOS tube.

[0075] As an example, the second switch tube M2 is a PMOS tube, the first end of the second switch tube M2 is the source of the PMOS tube, the second end of the second switch tube M2 is the drain of the PMOS tube, and the third end of the second switch tube M2 is the gate of the PMOS tube.

[0076] Generally, at the end of charging, the drain-source voltage (i.e., the voltage between the source and the source) of the NMOS tube rises, causing the gate-source voltage (i.e., the voltage between the gate and the source) of the NMOS tube to become smaller, and the on-resistance of the NMOS tube to increase, so that the impedance of the NMOS tube at the end of charging increases, and there is a situation of incomplete charging; but at the end of charging, the gate-source voltage of the PMOS tube does not become smaller, and therefore, the PMOS tube does not have the situation of incomplete charging.

[0077] In this example, the power distribution unit 1 includes a pre-charge main path 11 and at least one pre-charge branch path 12 that are turned on at different times, the pre-charge main path 11 is used for charging at the initial stage of charging, and at least one pre-charge branch path 12 is started at the middle stage and the end of charging to charge. Since the NMOS tube does not have the situation of incomplete charging at the initial stage of charging, the first switch tube M1 in the pre-charge main path 11 can be an NMOS tube or a PMOS tube; since the pre-charge branch path 12 mainly starts to charge at the middle stage and the end of charging, if an NMOS tube is used, there will be a situation of incomplete charging, and therefore, the second switch tube M2 in the pre-charge branch path 12 needs to be a PMOS tube to ensure normal charging at the middle stage and the end of charging.

[0078] In an embodiment, the first switch tube M1 is an NMOS tube, and the pre-charge main path 11 further includes 2N driving circuits, the 2N driving circuits are connected in series between the control port Vc and the third end of the first switch tube M1, and are used for performing even-numbered phase conversion on the first control signal to drive the NMOS tube to work; or, the first switch tube M1 is a PMOS tube, and the pre-charge main path 11 further includes 2N-1 driving circuits, the 2N-1 driving circuits are connected in series between the control port Vc and the third end of the first switch tube M1, and are used for performing odd-numbered phase conversion on the first control signal to drive the PMOS tube to work; wherein, N≥1.

[0079] As an example, the first switching transistor M1 in the pre-charge main circuit 11 can be an NMOS transistor. In this case, 2N driving circuits can also be set on the pre-charge main circuit 11 to drive the NMOS transistor. Specifically, the 2N driving circuits are connected in series between the control port Vc and the third terminal of the first switching transistor M1, so that the 2N driving circuits perform an even number of phase transitions on the first control signal input to the control port Vc. That is, each upper-level driving circuit inverts the first control signal it receives and inputs the inverted first control signal to its lower-level driving circuit to provide the NMOS transistor with a driving signal with the same phase as the first control signal, thereby meeting the high efficiency requirements of the NMOS transistor and driving it to work. In this example, by inverting the first control signal through 2N driving circuits, a driving signal with the same phase as the NMOS transistor can be provided, ensuring that it has a large driving capability and dynamic range.

[0080] As another example, the first switching transistor M1 in the pre-charge main circuit 11 can be a PMOS transistor. In this case, the pre-charge main circuit 11 can also be equipped with 2N-1 driving circuits to drive the PMOS transistors. Specifically, the 2N-1 driving circuits are connected in series between the control port Vc and the third terminal of the first switching transistor M1, so that the 2N-1 driving circuits can perform an odd number of phase transitions on the first control signal. That is, each upper-level driving circuit inverts the first control signal it receives and inputs the inverted first control signal to its lower-level driving circuit to provide the PMOS transistor with a driving signal that is opposite in phase to the first control signal, thereby meeting the low efficiency requirements of the PMOS transistor and driving it to work. In this example, by inverting the first control signal through 2N-1 driving circuits, a driving signal with opposite phase to the PMOS transistor can be provided, ensuring that it has a large driving capability and dynamic range.

[0081] In one embodiment, such as Figure 1 As shown, the pre-charge main circuit 11 also includes a first drive circuit 111 and a second drive circuit 112; the first drive circuit 111 includes a first load resistor Rn3 and a bias circuit 1111; the first load resistor Rn3 and the bias circuit 1111 are connected in series between the power supply port Vi and ground, and the bias circuit 1111 is also connected to the control port Vc; the second drive circuit 112 includes a third switch M3 and a second load resistor Rn4; the first end of the third switch M3 is connected to the power supply port Vi, the second end of the third switch M3 is grounded to GND through the second load resistor Rn4, and the third end of the third switch M3 is connected to the connection node between the first load resistor Rn3 and the bias circuit 1111; the third end of the first switch M1 is connected to the connection node between the third switch M3 and the second load resistor Rn4.

[0082] As an example, the first switching transistor M1 is an NMOS transistor, and the precharge main circuit 11 also includes two driving circuits, namely the first driving circuit 111 and the second driving circuit 112.

[0083] The first drive circuit 111 includes a first load resistor Rn3 and a bias circuit 1111 connected in series. The first end of the first load resistor Rn3 is connected to the power supply port Vi, the second end of the first load resistor Rn3 is grounded to GND through the bias circuit 1111, and the third end of the bias circuit 1111 is connected to the control port Vc. The bias circuit 1111 processes the first control signal input to the control port Vc and outputs a first bias voltage to the second drive circuit 112. The first load resistor Rn3 is the load of the bias circuit 1111 and is used to adjust the voltage swing of its node, i.e., to adjust the voltage swing of the first drive circuit 111. The resistance value of the first load resistor Rn3 can be determined based on the on-state voltage of its downstream switching transistor, specifically based on the on-state voltage of the third switching transistor M3.

[0084] The second drive circuit 112 includes a third switch M3 and a second load resistor Rn4 connected in series. The first terminal of the third switch M3 is connected to the power supply port Vi, and the second terminal of the third switch M3 is grounded to GND through the second load resistor Rn4. The third terminal of the third switch M3 is connected to the connection node between the first load resistor Rn3 and the bias circuit 1111. The third switch M3 can be turned on based on the first bias voltage output by the first drive circuit 111. When the third switch M3 is turned on, it can provide a first voltage Vng to the third terminal of the first switch M1. The first voltage Vng can keep the first switch M1 in the on state during the pre-charge stage to start the pre-charge main circuit 11 for pre-charge. The second load resistor Rn4 is the load of the third switch M3 and is used to adjust the voltage swing of its node, that is, to adjust the voltage swing of the second drive circuit 112. The resistance value of the second load resistor Rn4 can be determined according to the conduction voltage of its downstream switch, that is, according to the conduction voltage of the first switch M1.

[0085] In this example, the first drive circuit 111 includes a first load resistor Rn3 and a bias circuit 1111 connected in series. The bias circuit 1111 can process the first control signal input to the control port Vc to provide a first bias voltage to the third terminal of the third switch M3 for controlling the third switch M3 to conduct. The second drive circuit 112 includes a third switch M3 and a second load resistor Rn4 connected in series. When the third switch M3 conducts based on the first bias voltage, the on-resistance of the third switch M3 and the second load resistor Rn4 form a voltage divider circuit to divide the power supply voltage input to the power supply port Vi and provide a first voltage Vng to the third terminal of the first switch M1 so that the first switch M1 is always in the conducting state during the pre-charge stage to start the pre-charge main circuit 11 for pre-charge. Understandably, by using the first driving circuit 111 to invert the first control signal input to the control port Vc, and then using the second driving circuit 112 to invert the inverted first control signal output by the first driving circuit 111 again, a driving signal with the same phase as the first switching transistor M1 can be provided to ensure that it has a large driving capability and dynamic range, so as to control the operation of the first switching transistor M1.

[0086] In one embodiment, such as Figure 1 As shown, the bias circuit 1111 includes a first transistor Q1, a first bias resistor Rn1, and a second bias resistor Rn2; the first bias resistor Rn1 and the second bias resistor Rn2 are connected in series between the control port Vc and ground GND; the first terminal of the first transistor Q1 is connected to the first load resistor Rn3 and the third switch M3, the second terminal of the first transistor Q1 is grounded GND, and the third terminal of the first transistor Q1 is connected to the connection node between the first bias resistor Rn1 and the second bias resistor Rn2.

[0087] As an example, the bias circuit 1111 includes a first transistor Q1, a first bias resistor Rn1, and a second bias resistor Rn2. The first bias resistor Rn1 and the second bias resistor Rn2 are connected in series between the control port Vc and ground. That is, the first end of the first bias resistor Rn1 is connected to the control port Vc, the second end of the first bias resistor Rn1 is connected to the first end of the second bias resistor Rn2, and the second end of the second bias resistor Rn2 is grounded to GND. This allows the first control signal input to the control port Vc to be divided by the voltage divider circuit formed by the first bias resistor Rn1 and the second bias resistor Rn2. The first terminal of the first transistor Q1 is connected to the first load resistor Rn3 and the third terminal of the third switch M3. The second terminal of the first transistor Q1 is grounded to GND. The third terminal of the first transistor Q1 is connected to the connection node between the first bias resistor Rn1 and the second bias resistor Rn2, and conducts based on the second voltage Vnc between the two bias resistors. When the first transistor Q1 is conducting, the bias circuit 1111 can provide a first bias voltage to the third terminal of the third switch M3 to turn on the third switch M3. When the third switch M3 is conducting, the third switch M3, in conjunction with the second load resistor Rn4, can provide a first voltage Vng to the first switch M1 to control the first switch M1 to remain in the conducting state during the pre-charge phase. In this example, the first transistor Q1 and the third switch M3 cooperate to form an active circuit that controls the on / off state of the first switch M1, playing an inverting role in logic control.

[0088] In one embodiment, the third switch M3 has the opposite channel type to the first switch M1, and the first transistor Q1 has the opposite channel type to the third switch M3.

[0089] As an example, the third switch M3 has an opposite channel type to the first switch M1. This allows the second drive circuit 112, formed by the third switch M3 and the second load resistor Rn4, to invert the first control signal output from the first drive circuit 111 and output a drive signal to the first switch M1 that meets its operating requirements, ensuring that the first switch M1 remains in the on state during the pre-charge phase. Correspondingly, the first transistor Q1 has an opposite channel type to the third switch M3. This allows the first drive circuit 111, formed by the bias circuit 1111 containing the first transistor Q1 and the first load resistor Rn3, to invert the first control signal input to the control port Vc and output a drive signal to the first transistor Q1 that meets its operating requirements, thus turning on the third switch M3. The channel type here can be either N-channel or P-channel.

[0090] For example, when the first switch M1 is an NMOS transistor, the third switch M3 is a PMOS transistor, and the first transistor Q1 is an NPN transistor. Specifically, the source of the PMOS transistor is connected to the power supply port Vi, the drain of the PMOS transistor is connected to the first switch M1 and the second load resistor Rn4, and the gate of the PMOS transistor is connected to the first load resistor Rn3 and the NPN transistor in the bias circuit 1111. Correspondingly, the first transistor Q1 is an NPN transistor, the collector of the NPN transistor is connected to the second load resistor Rn4 and the gate of the PMOS transistor, the emitter of the NPN transistor is grounded to GND, and the base of the NPN transistor is connected to the connection node between the first bias resistor Rn1 and the second bias resistor Rn2. Specifically, it can be connected to the control port Vc through the first bias resistor Rn1. In this example, the PMOS transistor and the NPN transistor cooperate to form an inverting circuit that controls the on / off state of the NMOS transistor, thus playing an inverting role in logic control.

[0091] In one embodiment, such as Figure 1 As shown, the precharge branch 12 also includes a current source 121 and a soft start circuit 122; the first end of the current source 121 is connected to the control port Vc, and the second end of the current source 121 is connected to the soft start circuit 122, for outputting a soft start current to the soft start circuit 122 based on the second control signal; the first end of the soft start circuit 122 is connected to the power supply port Vi, and the second end of the soft start circuit 122 is connected to the current source 121 and the third end of the second switch M2, for outputting a soft start voltage to the second switch M2 based on the soft start current, so that the second switch M2 is always in the conducting state during the precharge stage.

[0092] As an example, the precharge branch 12 also includes a current source 121 and a soft-start circuit 122. The current source 121 is a circuit for providing a specific current; the soft-start circuit 122 is a circuit for soft-starting the second switching transistor M2 to reduce the starting current surge. Specifically, the first terminal of the current source 121 is connected to the control port Vc, and the second terminal of the current source 121 is connected to the soft-start circuit 122. After the current source 121 receives the second control signal input from the control port Vc, it processes the second control signal to form a soft-start current of a specific value and outputs the soft-start current to the soft-start circuit 122. Correspondingly, the first terminal of the soft start circuit 122 is connected to the power supply port Vi, and the second terminal of the soft start circuit 122 is connected to the current source 121 and the third terminal of the second switch M2. After receiving the soft start current, the soft start circuit 122 forms a soft start voltage to control the second switch M2, so that the second switch M2 is always in the conducting state during the pre-charging stage. This allows the corresponding pre-charging branch 12 to be connected to the power supply port Vi and the power distribution port Vo, and to charge in relay with the pre-charging main circuit 11. This allows the power distribution unit 1 to handle a larger proportion of current and heat dissipation compared to when the single pre-charging main circuit 11 is conducting.

[0093] In one embodiment, such asFigure 1 As shown, the current source 121 includes a second transistor Q2, a third bias resistor Rp1, a fourth bias resistor Rp2, and a third load resistor Rpc; the third bias resistor Rp1 and the fourth bias resistor Rp2 are connected in series between the control port Vc and ground GND; the first terminal of the second transistor Q2 is connected to the second terminal of the soft-start circuit 122, the second terminal of the second transistor Q2 is grounded to GND through the third load resistor Rpc, and the third terminal of the second transistor Q2 is connected to the connection node between the third bias resistor Rp1 and the fourth bias resistor Rp2.

[0094] As an example, the current source 121 includes a second transistor Q2, a third bias resistor Rp1, a fourth bias resistor Rp2, and a third load resistor Rpc. The first terminal of the third bias resistor Rp1 is connected to the control port Vc, and the second terminal of the third bias resistor Rp1 is connected to the first terminal of the fourth bias resistor Rp2. The second terminal of the fourth bias resistor Rp2 is grounded to GND. This allows the second control signal input to the control port Vc to be divided to provide a second bias voltage to the second transistor Q2, thereby controlling the second transistor Q2 to turn on or off. The first terminal of the second transistor Q2 is connected to the second terminal of the soft-start circuit 122, and the first terminal of the second transistor Q2 is also connected to the third terminal of the second switch M2. The second terminal of the second transistor Q2 is grounded to GND through the third load resistor Rpc. The third terminal of the second transistor Q2 is connected to the connection node between the third bias resistor Rp1 and the fourth bias resistor Rp2. The third load resistor Rpc is mainly used to convert the 3.3V or 5V second control signal into a soft-start current of a specific value, so that the soft-start circuit 122 outputs a soft-start voltage to the second switch M2 based on the soft-start current, so as to control the second switch M2 to always be in the conducting state during the pre-charge stage.

[0095] As an example, the channel type of the second transistor Q2 is opposite to that of the second switch M2, so that the current source 121 containing the second transistor Q2 has an inverting function, ensuring its driving capability and dynamic range for the subsequent switch. For example, if the second switch M2 is a PMOS transistor, then the second transistor Q2 can be an NPN transistor. The collector of the NPN transistor is the first terminal of the second transistor Q2, the emitter of the NPN transistor is the second terminal of the second transistor Q2, and the base of the NPN transistor is the third terminal of the second transistor Q2. That is, the collector of the NPN transistor is connected to the second terminal of the soft-start circuit 122 and the third terminal of the second switch M2; the emitter of the NPN transistor is grounded to GND through the third load resistor Rpc; the base of the NPN transistor is connected to the connection node between the third bias resistor Rp1 and the fourth bias resistor Rp2.

[0096] In one embodiment, such as Figure 1As shown, the soft-start circuit 122 includes a slow-start circuit 1221, a first diode Dp1, and a pull-up resistor Rp3; the pull-up resistor Rp3 and the current source 121 are connected in series between the power supply port Vi and ground GND; the first end of the slow-start circuit 1221 is connected to the power supply port Vi, the second end of the slow-start circuit 1221 is connected to the anode of the first diode Dp1, and the cathode of the first diode Dp1 is connected to the third end of the second switch M2; the cathode of the first diode Dp1 is also connected to the connection node between the pull-up resistor Rp3 and the current source 121, which is used to turn on the soft-start current based on the output of the current source 121, output a soft-start voltage to the second switch M2, and control the second switch M2 to be in the on state during the pre-charge stage.

[0097] As an example, the soft-start circuit 122 includes a soft-start circuit 1221, a first diode Dp1, and a pull-up resistor Rp3. The pull-up resistor Rp3 and the current source 121 are connected in series between the power supply port Vi and ground. That is, the first end of the pull-up resistor Rp3 is connected to the power supply port Vi, and the second end of the pull-up resistor Rp3 is grounded to GND through the current source 121. When the current source 121 receives the second control signal input from the control port Vc, it can output a soft-start current of a specific value, so that the soft-start current flows through the circuit where the pull-up resistor Rp3 and the current source 121 are located. The first terminal of the soft-start circuit 1221 is connected to the power supply port Vi, and the second terminal of the soft-start circuit 1221 is connected to the anode of the first diode Dp1. The cathode of the first diode Dp1 is connected to the third terminal of the second switch M2. The cathode of the first diode Dp1 is also connected to the connection node between the pull-up resistor Rp3 and the current source 121. When the current source 121 receives the PWM signal or level signal input from the control port Vc, it provides a pull-down voltage to the first diode Dp1, making the first diode Dp1 conduct. The soft-start circuit 1221 realizes the soft-start delay function and outputs a soft-start voltage to the second switch M2, controlling the second switch M2 to remain in the conducting state during the pre-charge stage. Conversely, when the current source 121 does not receive the PWM signal or level signal input from the control port Vc, the pull-up resistor Rp3 provides a pull-up voltage to the first diode Dp1, making the first diode Dp1 and the second switch M2 turn off.

[0098] The soft-start circuit 122 provided in this example is relatively simple, yet cleverly combines the characteristics of slow RC delay and fast PWM signal response. Specifically, the first diode Dp1 is used to achieve isolation and voltage limiting between the fast charging branch and the slow charging branch. Here, the fast charging branch refers to the branch where the pull-up resistor Rp3 is located, while the slow charging branch is the branch where the series-connected soft-start circuit 1221 is located. The soft-start circuit 1221 is used to achieve soft-start delay, the pull-up resistor Rp3 is used to achieve fast pull-up of the PWM signal, and the current source 121 is used to achieve fast pull-down of the PWM signal. This allows the soft-start circuit 122 to be controlled not only by a level signal but also by a rapidly changing PWM signal, enabling it to exhibit a specified delay and voltage soft-start.

[0099] In one embodiment, the soft-start circuit 1221 includes a soft-start resistor Rp4 and a soft-start capacitor Cp1 connected in parallel.

[0100] As an example, the soft-start circuit 1221 includes a soft-start resistor Rp4 and a soft-start capacitor Cp1 connected in parallel. The two ends of the soft-start resistor Rp4 are connected to the power supply port Vi and the anode of the first diode Dp1, respectively. The two ends of the soft-start capacitor Cp1 are connected to the power supply port Vi and the anode of the first diode Dp1, respectively. By utilizing the characteristic that the voltage across the soft-start capacitor Cp1 cannot change abruptly, the inrush current during startup is limited by the soft-start resistor Rp4. As the power supply voltage input to the power supply port Vi charges the soft-start capacitor Cp1, the voltage of the soft-start capacitor Cp1 gradually increases and the current gradually decreases, thereby achieving soft-start delay. This can effectively limit the inrush current during startup and ensure that the components in the circuit are not damaged.

[0101] As an example, let Vsup be the supply voltage of the power supply port Vi; Vc be the voltage at the connection node between the soft-start circuit 122 and the first diode Dp1; Vpg be the gate voltage of the second switch M2; Vrc be the charging voltage drop of the soft-start circuit 122; Vgs be the gate-source voltage of the second switch M2; Vd be the forward voltage drop of the first diode Dp1; Rp1 be the resistance of the third bias resistor Rp1; Rp2 be the resistance of the fourth bias resistor Rp2; Rpc be the resistance of the third load resistor Rpc; Vpn be the forward voltage drop of the second transistor Q2; Rp4 be the resistance of the soft-start resistor Rp4; and Cp1 be the capacitance of the soft-start capacitor Cp1. Then the working principle of the pre-charge branch 12 is as follows:

[0102] When the precharge branch 12 is powered on, the voltage Vc of the connection node between the soft start circuit 122 and the first diode Dp1 is the power supply voltage Vsup of the power supply port Vi, that is, Vc=Vsup.

[0103] (2) After the pre-charge branch 12 is enabled, that is, after the second control signal is input to the control port Vc, the current source 121 connected to the control port Vc pulls down the soft start circuit 122, causing the first diode Dp1 to conduct. At this time, the soft start circuit 122 charges slowly according to the RC constant. At this time, the gate-source voltage Vgs of the second switching transistor M2 is the sum of the charging voltage drop Vrc of the soft start circuit 122 and the conduction voltage drop of the first diode Dp1, that is, Vgs = Vrc + Vd. This gate-source voltage Vgs can keep the second switching transistor M2 in the conducting state during the pre-charge stage, so that the pre-charge branch 12 and the pre-charge main path 11 perform pre-charge operations together.

[0104] (3) During the slow charging process of the soft start circuit 122, the charging voltage drop Vrc of the soft start circuit 122 gradually increases. When the voltage difference between both ends of the first diode Dp1 is less than its conduction voltage drop, the first diode Dp1 is cut off and the soft start ends.

[0105] In this example, the unidirectional conducting first diode Dp1 captures and provides the gate voltage required by the second switching transistor M2 before and after soft start, enabling the soft start circuit 122 to support PWM signal inputs with a wide range of duty cycles and also support level signal inputs with a duty cycle of 100%. When the level signal has a duty cycle of 100%, the PWM signal has a duty cycle of 40%, and the PWM signal has a duty cycle of 20%, the corresponding working envelope waveforms of the soft start circuit 122 are respectively as Figure 3 shown in 3A, 3B, and 3C in.

[0106] In this example, the circuit parameters of the soft start circuit 122 are determined by the specific parameters of the pull-up resistor Rp3, the slow start resistor Rp4, the slow start capacitor Cp1, and the first diode Dp1. Its specific circuit parameters meet the following conditions:

[0107] Ip * Rp3 > Vd, Vrc = Vsup - Vc, Vgs = Vsup - Vpg;

[0108] Among them, the soft start current Ip output by the current source 121 can be determined based on the following formula (3):

[0109] Ip = (Vct1 * Rp2 / (Rp1 + Rp2) - Vpn) / Rpc... (3)

[0110] Among them, the charging voltage drop Vrc of the soft start circuit 122 can be determined based on the following formula (4):

[0111] If Vrc < Ip * Rp3 - Vd, then Vgs = Vd + Vrc;

[0112] If Vrc ≥ Ip * Rp3 - Vd, then Vgs = Ip(t) * Rp3... (4)

[0113] The soft-start delay of the soft-start circuit 122 can be determined based on the following formula (5):

[0114] Tpd=-Rp4*Cp1*ln⌊1-(Ip*Rp3-Vd) / Ip*Rp3⌋……(5)

[0115] In one embodiment, the precharge branch 12 further includes a varistor-sensitive gating circuit 123; the first terminal of the varistor-sensitive gating circuit 123 is connected to the third terminal of the second transistor Q2, and the second terminal of the varistor-sensitive gating circuit 123 is connected to the power distribution port Vo.

[0116] As an example, the varistor selection circuit 123 is a circuit based on a unidirectional conducting element, which can conduct unidirectionally when a specific condition is met. In this example, the varistor selection circuit 123 is connected across the third terminal of the second transistor Q2 (such as the base of an NPN transistor) and the power distribution port Vo. In the initial stage of charging, the voltage of the power distribution port Vo is low, and the voltage Vpt of the third terminal of the second transistor Q2 (such as the base of an NPN transistor) is pulled down, so that the entire current source 121 has no output. At this time, even if the second control signal Vct1 input to the control port Vc is shielded, the entire pre-charge branch 12 is in the closed state, that is, in the non-starting state. When the second control signal is shielded, according to the second control signal, and the specific circuit design of the current source 121 and the varistor selection circuit 123, the power distribution voltage Vout at the power distribution port Vo is designed according to the following formula (6):

[0117] Vout≥Vct1*Rp2 / (Rp1+Rp2)-Vdx……(6)

[0118] Wherein, Vout is the power distribution voltage of the pre-charge branch 12, which can control the pre-charge branch 12 to connect to the pre-charge main line 11 for charging; Vct1 is the voltage corresponding to the second control signal; Rp1 is the resistance value of the third bias resistor Rp1; Rp2 is the resistance value of the fourth bias resistor Rp2; and Vdx is the on-state voltage drop of the unidirectional conducting element.

[0119] In one embodiment, the varistor selection circuit 123 includes a second diode Dp2, the anode of which is connected to the third terminal of the second transistor Q2, and the cathode of which is connected to the power distribution port Vo; or, the varistor selection circuit 123 includes at least two second diodes Dp2 connected in series; the anode of the first second diode Dp2 is connected to the third terminal of the second transistor Q2, and the cathode of the last second diode Dp2 is connected to the power distribution port Vo.

[0120] As an example, the varistor selection circuit 123 can be a second diode Dp2. The anode of the second diode Dp2 is connected to the third terminal of the second transistor Q2, and the cathode of the second diode Dp2 is connected to the power distribution port Vo. When the power distribution voltage Vout of the power distribution port Vo is low, the base voltage of the NPN transistor can be pulled down, so that the NPN transistor does not conduct. Therefore, the current source 121 has no soft-start current output. When the power distribution voltage Vout of the power distribution port Vo is high and the above formula (6) is satisfied, the base voltage of the NPN transistor can be ensured to be high, so that it can conduct, thereby enabling the current source 121 to output soft-start current.

[0121] Similarly, the varistor selection circuit 123 can also include at least two second diodes Dp2 connected in series. The anode of the first second diode Dp2 is connected to the third terminal of the second transistor Q2, and the cathode of the last second diode Dp2 is connected to the power distribution port Vo. The number of second diodes Dp2 can be determined according to actual needs. Multiple second diodes Dp2 work together to determine the forward voltage drop of the entire varistor selection circuit so as to adapt to different power distribution voltages. Here, the second diode Dp2 is the unidirectional conducting element in formula (6).

[0122] This utility model embodiment provides a power distribution module, such as Figure 4 As shown, the power distribution module includes a control unit 2 and a power distribution unit 1 in the above embodiment; the control unit 2 is connected to the control port Vc and is used to output a first control signal and at least one second control signal to the control port Vc in sequence.

[0123] As an example, the power distribution module includes a control unit 2 and a power distribution unit 1 connected to the control unit 2. The control unit 2 is connected to the control port Vc in the power distribution unit 1. It can output a first control signal and at least one second control signal sequentially according to the actual situation. The first control signal output first can control the first switch M1 to be in the conducting state during the pre-charging stage, so that the pre-charging main circuit 11 can perform pre-charging operation. During the pre-charging operation of the pre-charging main circuit 11, the second control signal output later controls a second switch M2 to be in the conducting state during the pre-charging stage, so that the pre-charging branch 12 where the second switch M2 is located can be turned on. This realizes the control of the pre-charging main circuit 11 and at least one pre-charging branch 12 to be turned on at the same time for pre-charging operation, so that the power distribution unit 1 can realize time-sharing multi-point current flow heat dissipation, which helps to reduce the current flow heat dissipation pressure and current flow heat dissipation capacity of the power distribution unit 1 to meet the current flow heat dissipation requirements.

[0124] In one embodiment, the control unit 2 is configured to output a first control signal to the first switch M1 at the moment the power distribution unit 1 is powered on, controlling the first switch M1 to remain in the on state during the pre-charging phase, so that the pre-charging main circuit 11 can perform pre-charging operation, and to obtain the power distribution voltage corresponding to the control port Vc; when the power distribution voltage reaches the on-state voltage corresponding to any pre-charging branch 12, the control unit 2 outputs a second control signal to the second switch M2 of the pre-charging branch 12 that has reached the on-state voltage, controlling the second switch M2 to remain in the on state during the pre-charging phase, so that the pre-charging branch 12 corresponding to the second switch M2 can perform pre-charging operation.

[0125] As an example, the control unit 2 can output a first control signal to the first switch tube M1 at the moment the power distribution unit 1 is powered on, for example, when it is necessary to charge the power supply 3 connected to the power distribution unit 1 through a charging pile or other energy storage device. This allows the power supply 3 to precharge the bus capacitor 5 connected to the power distribution port Vo through the precharge main circuit 11, thus avoiding a large surge current at the moment of power-on. During the pre-charging process of the power supply 3 to the bus capacitor 5 through the pre-charging main circuit 11, the distribution voltage of the distribution port Vo will rise. Therefore, the control unit 2 can obtain the distribution voltage of the distribution port Vo through the detection circuit and compare it with the conduction voltage corresponding to each pre-charging branch 12. When the distribution voltage reaches the conduction voltage corresponding to any pre-charging branch 12, the control unit 2 can output a second control signal to the second switch M2 in the pre-charging branch 12 that has reached the conduction voltage, so that the corresponding second switch M2 is always in the conducting state during the pre-charging stage. This allows the power supply 3 to pre-charge the bus capacitor 5 through the pre-charging branch 12. By cooperating with the pre-charging main circuit 11 and at least one pre-charging branch 12, time-sharing multi-point current-carrying heat dissipation is achieved, which helps to reduce the current-carrying heat dissipation pressure and current-carrying heat dissipation capacity of the power distribution unit 1 to meet the current-carrying heat dissipation requirements. In this example, when the number of pre-charging branches 12 is at least two, the conduction voltages of at least two pre-charging branches 12 are different.

[0126] like Figure 2 As shown, the working process of the control unit 2 controlling the first switch M1 and at least one second switch M2 in the power distribution unit 1 to conduct in a time-sharing manner is as follows:

[0127] At the moment the power distribution unit 1 is powered on, the control unit 2 can control the first switch M1 of the pre-charge main circuit 11 to be in the on state during the pre-charge stage based on the first control signal input at the control port Vc. Only the pre-charge main circuit 11 is started, so that the power supply 3 charges the bus capacitor 5 through the pre-charge main circuit 11 and detects the capacitor voltage of the bus capacitor 5 in real time.

[0128] When the control unit 2 determines that the capacitor voltage of the bus capacitor 5 has been charged from 0V to Va, it can determine that it has reached the conduction voltage corresponding to the first pre-charge branch 12. At this time, it can output the first second control signal to the second switch M2 corresponding to the first pre-charge branch 12, and control the second switch M2 of the first pre-charge branch 12 to be in the conducting state during the pre-charge stage, so that the pre-charge main circuit 11 and the first pre-charge branch 12 are started, so that the power supply 3 charges the bus capacitor 5 through the pre-charge main circuit 11 and the pre-charge branch 12, and detects the capacitor voltage of the bus capacitor 5 in real time.

[0129] When the control unit 2 determines that the capacitor voltage of the bus capacitor 5 has been charged from Va to Vb, it can determine that it has reached the conduction voltage corresponding to the second pre-charge branch 12. At this time, it can output a second control signal to the second switch M2 corresponding to the second pre-charge branch 12, and control the second switch M2 of the second pre-charge branch 12 to be in the conducting state during the pre-charge stage, so that the pre-charge main circuit 11 and the two pre-charge branches 12 are started, and the power supply 3 charges the bus capacitor 5 through the pre-charge main circuit 11 and the two pre-charge branches 12.

[0130] This utility model embodiment provides an electronic device, such as... Figure 4 As shown, the electronic device includes a power supply 3, a power bus 4, a bus capacitor 5, and the power distribution module in the above embodiment; the power supply 3 is connected to the power supply port Vi of the power distribution unit 1; the bus capacitor 5 is connected to the power distribution port Vo of the power distribution unit 1 through the power bus 4.

[0131] As an example, the electronic device includes a power supply 3, a power bus 4, a bus capacitor 5, and a power distribution module. The power supply 3 can be, but is not limited to, a battery. The power bus 4 refers to the bus connected to the positive and negative terminals of the power supply 3. The power distribution module includes a control unit 2 and a power distribution unit 1 connected to the control unit 2. The power distribution unit 1 includes a pre-charge main circuit 11 connected in parallel to the power supply port Vi and the power distribution port Vo, and at least one pre-charge branch circuit 12. The pre-charge main circuit 11 includes a power resistor Rpow and a first switch M1 connected in series. The pre-charge branch circuit 12 includes a second switch M2. Capacitor 5 is connected to the power distribution port Vo of power distribution unit 1 via power bus 4; control unit 2 is connected to the control port Vc in power distribution unit 1, and can output a first control signal to the first switch M1 and a second control signal to at least one second switch M2 in a time-sharing manner according to the actual situation, so that the pre-charging main circuit 11 where the first switch M1 is located and the pre-charging branch circuit 12 where at least one second switch M2 is located are connected in a time-sharing manner to perform pre-charging operation, so that power distribution unit 1 can realize time-sharing multi-point current flow heat dissipation, which helps to reduce the current flow heat dissipation pressure and current flow heat dissipation capacity of power distribution unit 1 to meet the current flow heat dissipation requirements.

[0132] As an example, the electronic device is a vehicle.

[0133] This utility model embodiment provides a power distribution unit simulation design method. Taking the applicability of this power distribution unit simulation design method to any computer device capable of simulation calculation as an example, such as... Figure 5 As shown, the simulation design method for power distribution unit 1 includes the following steps:

[0134] S1: Obtain the target performance requirements of power distribution unit 1;

[0135] S2: Determine the pre-charge main circuit 11, perform simulation analysis on the pre-charge main circuit 11, and determine the target device type of the pre-charge main circuit 11;

[0136] S3: Determine the initial configuration information of power distribution unit 1. The initial configuration information includes the number of pre-charge branches 12, the heat dissipation ratio of pre-charge main line 11 and pre-charge branches 12, the start-up characteristic point of each pre-charge branch 12, the estimated duty cycle, and the device parameters of power distribution unit 1.

[0137] S4: Based on the target device type of the pre-charge main circuit 11 and the initial configuration information of the power distribution unit 1, perform simulation analysis to determine the simulation results corresponding to the power distribution unit 1;

[0138] S5: If the simulation results corresponding to power distribution unit 1 do not meet the target performance requirements, then update the initial configuration information of power distribution unit 1.

[0139] S6: If the simulation results corresponding to power distribution unit 1 meet the target performance requirements, then the initial configuration information will be determined as the target configuration information corresponding to the power distribution unit.

[0140] As an example, in step S1, the computer device can receive the target performance requirements input by the user. These target performance requirements are the performance requirements that the user needs to achieve when developing and designing the power distribution unit 1, including but not limited to the capacitance value C of the power bus 4 to ground, the power supply voltage Vs, and the allowable charging delay time S, so that the simulation design results of the power distribution unit 1 can be verified based on the target performance requirements, thereby ensuring that the designed power distribution unit 1 meets its predetermined design requirements.

[0141] As an example, in step S2, the computer device may receive user input of the precharge main circuit 11, which may receive the prototype circuit selected by the user, such as... Figure 6 As shown, the prototype circuit includes a pre-charge main circuit 11 formed by a power resistor Rpow and a first switching transistor M1 connected in series; simulation analysis is performed on the pre-charge main circuit 11 to determine the simulation results corresponding to the pre-charge main circuit 11 (e.g., Figure 7(as shown); then, based on the simulation results of the pre-charge main circuit 11, the target device type corresponding to the pre-charge main circuit 11 is determined. Specifically, the target device type corresponding to the power resistor Rpow is determined. The target device type corresponding to the power resistor Rpow can be any one of metal film resistor, chip resistor, cement resistor and aluminum shell resistor.

[0142] In this example, the computer device can use the above formulas (1) and (2) to calculate the peak current, peak thermal power and peak dissipation power of the power resistor Rpow and the first switching transistor M1, and compare the functional performance parameters of the pre-charge main circuit 11 with the target performance requirements. If the functional performance parameters of the pre-charge main circuit 11 meet the target performance requirements, the simulation design of the pre-charge main circuit 11 is directly considered to be completed. If the functional performance parameters of the pre-charge main circuit 11 do not meet the target performance requirements, step S3 needs to be executed.

[0143] As an example, in step S3, the computer device can also receive initial configuration information corresponding to the power distribution unit 1 input by the user. The initial configuration information includes the number of pre-charge branches 12, the determined heat dissipation ratio between the pre-charge main circuit 11 and the pre-charge branches 12, the startup characteristic point of each pre-charge branch 12, and the device parameters of the power distribution unit 1. Here, the heat dissipation ratio refers to the heat dissipation ratio between the pre-charge main circuit 11 and at least one pre-charge branch 12, which can also be understood as the current power consumption allocation ratio. Here, the startup characteristic point refers to the position of each pre-charge branch 12 in a pre-set power-on curve, used to reflect the startup time and conduction voltage of each pre-charge branch 12. This characteristic point position can be displayed in a (time, voltage) format, for example... Figure 2 The starting characteristic point corresponding to the first pre-charge branch 12 is (Ta, Va), and the starting characteristic point corresponding to the second pre-charge branch 12 is (Tb, Vb). The device parameters of the power distribution unit 1 here refer to the parameters of each component in the power distribution unit 1, including but not limited to the resistance value of resistors and the capacitance value of capacitors, specifically including the parameters of each component in the pre-charge main circuit 11 and the parameters of each component in the pre-charge branch 12.

[0144] As an example, in step S4, the computer device can determine the preliminary design of the power distribution unit 1 based on the target device type of the pre-charge main circuit 11 and the initial configuration information corresponding to the power distribution unit 1, perform simulation analysis on the preliminary design of the power distribution unit 1, and determine the simulation result corresponding to the preliminary design of the power distribution unit 1. In this example, after the computer device has preliminarily designed the power distribution unit 1, it also needs to receive the control parameters such as the soft start current Ip, charging voltage drop Vre, soft start delay Tpd, PWM period, soft start delay and estimated duty cycle of each pre-charge branch 12 input by the user, perform simulation analysis based on the above control parameters and the above formulas (3)-(5), determine the simulation charging curve, and determine the simulation result corresponding to the power distribution unit 1; then compare the simulation result with the target performance requirements determined in step S1, so as to determine whether to execute step S5 or step S6 according to the comparison result.

[0145] As an example, in step S5, when the simulation results corresponding to power distribution unit 1 do not meet the target performance requirements, the computer equipment can adjust the device parameters and / or control parameters such as the estimated duty cycle of power distribution unit 1. After adjustment, the simulation calculation is performed again. That is, using the updated initial configuration information, step S4 is repeated so that the comparison between the recalculated simulation results and the target performance requirements can be used to determine whether the initially designed power distribution unit 1 meets the target performance requirements.

[0146] As an example, in step S6, when the simulation results corresponding to power distribution unit 1 meet the target performance requirements, the computer device determines that the initially designed power distribution unit 1 is the power distribution unit 1 that meets the target performance requirements. The initial configuration information of the pre-charge main circuit 11 determined in the simulation process can be determined as the target configuration information of the pre-charge main circuit 11. The target configuration information here includes the number of pre-charge branches 12 determined through simulation analysis, the heat dissipation ratio of the pre-charge main circuit 11 and the pre-charge branches 12, the start-up characteristic point of each pre-charge branch 12, the estimated duty cycle, and the device parameters of power distribution unit 1.

[0147] For example, this utility model embodiment provides a power distribution unit 1, such as Figure 8 As shown, the power distribution unit 1 includes a pre-charging main circuit 11 and two pre-charging branch circuits 12 connected in parallel. Its design process is as follows:

[0148] (1) The computer equipment obtains the target performance requirements of the power distribution unit 1 input by the user. The target performance requirements include the capacitance value of the power bus 4 to ground C=23mF; the power supply voltage Vs=16V; and the allowable charging delay time S=0.5s.

[0149] (2) The computer equipment can obtain the pre-charge main circuit 11 determined by the user, perform simulation analysis on the pre-charge main circuit 11, and determine the simulation results corresponding to the pre-charge main circuit 11 as follows:Figure 7 As shown, when the pre-charge main circuit 11 includes a power resistor Rpow and a first switching transistor M1 connected in series, if the power resistor Rpow has a value of 5 ohms, the charging delay is 0.5s, the peak thermal power of the power resistor Rpow is 51.2W, and the peak dissipation power within the window time of 0.1s is 24.2W. Based on the simulation results corresponding to the pre-charge main circuit 11, the target device type of the power resistor Rpow is determined to be a cement resistor with a larger size.

[0150] (3) The computer equipment needs to determine the initial configuration information of the precharge branch 12, which includes, but is not limited to, the number of precharge branches 12, the heat dissipation ratio of the precharge main circuit 11 and the precharge branch 12, the start-up characteristic point of each precharge branch 12, the estimated duty cycle, and the device parameters of the power distribution unit 1. For example, the number of precharge branches 12 is set to 2, the heat dissipation ratio of the precharge main circuit 11 and the two precharge branches 12 is pre-designed to be 1:1:0.5, the start-up characteristic points of the two precharge branches 12 are (0.1s, 2V) and (0.2s, 5V) respectively, and the estimated duty cycle is 20%.

[0151] (4) After determining the target device type in the pre-charging main circuit 11 and the initial configuration information corresponding to the power distribution unit 1, the computer equipment forms a pre-designed power distribution unit 1, performs simulation analysis on the pre-designed power distribution unit 1, and determines the simulation results corresponding to the pre-designed power distribution unit 1; if the simulation results do not meet the pre-set target performance requirements, the device parameters and / or control parameters such as the estimated duty cycle in the power distribution unit 1 are adjusted, and the simulation analysis is performed again; if the simulation results meet the pre-set target performance requirements, the device parameters of the pre-charging main circuit 11 and the device parameters of the pre-charging branch circuit 12 are determined as follows:

[0152] The device parameters corresponding to the pre-charge main circuit 11 are as follows: power resistor Rpow = 10 ohms; first bias resistor Rn1 = 10K ohms; second bias resistor Rn2 = first load resistor Rn3 = 47K ohms; second load resistor Rn4 = 100K ohms.

[0153] The device parameters corresponding to the first precharge branch 121 are as follows: third bias resistor Rp11 = 10k ohms; fourth bias resistor Rp21 = third load resistor Rpc1 = 47k ohms; pull-up resistor Rp31 = 100k ohms; soft-start resistor Rp41 = 200k ohms; soft-start capacitor Cp11 = 0.22uF; the varistor gating circuit 123 corresponding to the first precharge branch 121 includes two ordinary second diodes Dp21 connected in series, and the forward voltage drop of the second diodes Dp21 is Vd = 0.6V.

[0154] The device parameters corresponding to the second precharge branch 122 are as follows: third bias resistor Rp12 = 10k ohms; fourth bias resistor Rp22 = third load resistor Rpc2 = 47k ohms; pull-up resistor Rp32 = 100k ohms; soft-start resistor Rp42 = 200k ohms; soft-start capacitor Cp12 = 0.47uF; the varistor gating circuit 123 corresponding to the first precharge branch 12 includes a general-purpose second diode Dp22, and the forward voltage drop of the second diode Dp22 is Vd = 0.6V.

[0155] Figure 9 yes Figure 8 The simulation results of the power distribution unit 1 shown are used to illustrate the changes in current I, voltage V, and heat dissipation W over time in the pre-charge main circuit 11 and the two pre-charge branches 12. The control signal is a 25% PWM signal. Figure 9 It can be seen that the peak currents of the first switch M1 in the pre-charge main circuit 11, the second switch M21 in the first pre-charge branch 121, and the second switch M22 in the second pre-charge branch 122 are 1.6A, 3.2A, and 2.2A, respectively, and occur at 0s, 0.25s, and 0.43s; the peak power occurs at 0s, 0.23s, and 0.32s, respectively. The three paths achieve time-sharing coordination to achieve power sharing between channels and a shorter power-on time.

[0156] Figure 10 yes Figure 8 The simulation results of the power distribution unit 1 shown are used to reflect the voltage curves of the PWM signal with Rpow=10 ohms and duty cycles of 10%, 25%, and 60%, and to compare them with the voltage curves of the existing series resistor scheme at 10 ohms and 5 ohms. Specifically, in the charging scenario, C=23mF and Vs=16V.

[0157] Figure 11 yes Figure 8 The simulation results of the power distribution unit 1 shown are compared with those of the existing RC pre-charging circuit. Figure 11 It can be seen that when the input PWM signal is 25%, the power-on delay time is 0.5s, the absolute peak power of the power resistor Rpow is 25.5W, and the 0.1s window power is 5.5W, which is 23% of the original 24.2W; the absolute peak power of the PMOS transistor in the precharge branch 121 is 29.2W, and the 0.1s window power is 6.5W; the absolute peak power of the PMOS transistor in the precharge branch 122 is 14.0W, and the 0.1s window power is 3.3W. The power-on curve is smoother than the traditional technology, and the characteristic points experienced by the power-on curve are (0.1s, 2V) and (0.2s, 4.2V).

[0158] The power distribution unit 1 provided in this embodiment of the present invention has the following advantages compared to the traditional series connection of power resistor Rpow and switch: First, it breaks through the conventional charging curve with varying RC charging exponent, allowing for deep customization of the charging voltage curve and time delay. When the charging time is comparable, the voltage and current are smoother than in conventional solutions. Second, the power of the power resistor Rpow on the pre-charging main circuit 11 is significantly derated, the resistor type can be adjusted, and the space requirement is reduced; the pre-charging branch 12 can be further derated, reducing the cost of electronic components. Third, the first switch M1 and the second switch M2 do not require boost charge pump support, helping to save costs. Fourth, the entire solution only requires one MCU output port. The charging curve and time delay are controlled in an open-loop manner through level signals or adjustment of the PWM duty cycle, eliminating the need for MCU closed-loop control support and minimizing MCU occupancy and dependency.

[0159] The above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model, and should all be included within the protection scope of this utility model.

Claims

1. A power distribution unit, comprising a power supply port, a power distribution port, and a control port, characterized in that, The power distribution unit also includes a pre-charge main circuit and at least one pre-charge branch circuit: The pre-charge main circuit includes a power resistor and a first switching transistor. The first end of the first switching transistor is connected to the power supply port through the power resistor, the second end of the first switching transistor is connected to the power distribution port, and the third end of the first switching transistor is connected to the control port. Each of the pre-charge branches includes a second switch, the first end of which is connected to the power supply port, the second end of which is connected to the power distribution port, and the third end of which is connected to the control port. The control port is used to receive a first control signal and at least one second control signal input sequentially. The first control signal is used to control the first switching transistor to remain in the conducting state during the pre-charge phase, so that the pre-charge main circuit can perform pre-charge operation; Each of the second control signals is used to control a second switch to remain in the on state during the pre-charge phase, so that the pre-charge branch corresponding to the second switch can perform a pre-charge operation.

2. The power distribution unit according to claim 1, characterized in that, The first switching transistor is an NMOS transistor or a PMOS transistor; the second switching transistor is a PMOS transistor.

3. The power distribution unit according to claim 2, characterized in that, The first switching transistor is an NMOS transistor. The precharge main circuit also includes 2N driving circuits. The 2N driving circuits are connected in series between the control port and the third terminal of the first switching transistor. They are used to perform an even number of phase transitions on the first control signal to drive the NMOS transistor to work. Alternatively, the first switching transistor is a PMOS transistor, and the pre-charge main circuit further includes 2N-1 driving circuits. The 2N-1 driving circuits are connected in series between the control port and the third terminal of the first switching transistor, and are used to perform an odd number of phase transitions on the first control signal to drive the PMOS transistor to work; wherein, N≥1.

4. The power distribution unit according to claim 2, characterized in that, The pre-charge main circuit also includes a first drive circuit and a second drive circuit. The first driving circuit includes a first load resistor and a bias circuit; the first load resistor and the bias circuit are connected in series between the power supply port and ground, and the bias circuit is also connected to the control port; The second driving circuit includes a third switching transistor and a second load resistor; the first end of the third switching transistor is connected to the power supply port, the second end of the third switching transistor is grounded through the second load resistor, and the third end of the third switching transistor is connected to the connection node between the first load resistor and the bias circuit. The third terminal of the first switching transistor is connected to the connection node between the third switching transistor and the second load resistor.

5. The power distribution unit according to claim 4, characterized in that, The bias circuit includes a first transistor, a first bias resistor, and a second bias resistor; The first bias resistor and the second bias resistor are connected in series between the control port and ground; The first terminal of the first transistor is connected to the first load resistor and the third switching transistor, the second terminal of the first transistor is grounded, and the third terminal of the first transistor is connected to the connection node between the first bias resistor and the second bias resistor.

6. The power distribution unit according to claim 1, characterized in that, The precharge branch also includes a current source and a soft start circuit; The first end of the current source is connected to the control port, and the second end of the current source is connected to the soft start circuit, for outputting a soft start current to the soft start circuit based on the second control signal; The first terminal of the soft-start circuit is connected to the power supply port, and the second terminal of the soft-start circuit is connected to the current source and the third terminal of the second switching transistor. It is used to output a soft-start voltage to the second switching transistor based on the soft-start current, so that the second switching transistor is always in the conducting state during the pre-charging stage.

7. The power distribution unit according to claim 6, characterized in that, The current source includes a second transistor, a third bias resistor, a fourth bias resistor, and a third load resistor; The third bias resistor and the fourth bias resistor are connected in series between the control port and ground; The first terminal of the second transistor is connected to the second terminal of the soft-start circuit, the second terminal of the second transistor is grounded through the third load resistor, and the third terminal of the second transistor is connected to the connection node between the third bias resistor and the fourth bias resistor.

8. The power distribution unit according to claim 6, characterized in that, The soft-start circuit includes a soft-start circuit, a first diode, and a pull-up resistor; The pull-up resistor and the current source are connected in series between the power supply port and ground. The first terminal of the soft-start circuit is connected to the power supply port, the second terminal of the soft-start circuit is connected to the anode of the first diode, and the cathode of the first diode is connected to the third terminal of the second switching transistor. The cathode of the first diode is also connected to the connection node between the pull-up resistor and the current source, for conducting based on the soft-start current output by the current source, outputting a soft-start voltage to the second switch, and controlling the second switch to remain in the conducting state during the pre-charge phase.

9. The power distribution unit according to claim 8, characterized in that, The soft-start circuit includes a soft-start resistor and a soft-start capacitor connected in parallel.

10. The power distribution unit according to claim 7, characterized in that, The pre-charge branch also includes a pressure-sensitive gating circuit; The first terminal of the varistor is connected to the third terminal of the second transistor, and the second terminal of the varistor is connected to the power distribution port.

11. The power distribution unit according to claim 10, characterized in that, The varistor selection circuit includes a second diode, the anode of which is connected to the third terminal of the second transistor, and the cathode of which is connected to the power distribution port. Alternatively, the varistor selection circuit includes at least two second diodes connected in series; the anode of the first second diode is connected to the third terminal of the second transistor, and the cathode of the last second diode is connected to the power distribution port.

12. A power distribution module, characterized in that, Includes a control unit and a power distribution unit as described in any one of claims 1-11; The control unit is connected to the control port and is used to output a first control signal and at least one second control signal to the control port in sequence.

13. The power distribution module according to claim 12, characterized in that, The control unit is used to output a first control signal to the first switch tube at the moment the power distribution unit is powered on, to control the first switch tube to remain in the conducting state during the pre-charging stage, so that the pre-charging main circuit can perform pre-charging operation, and to obtain the power distribution voltage corresponding to the control port. When the power distribution voltage reaches the conduction voltage corresponding to any of the pre-charge branches, a second control signal is output to the second switch of the pre-charge branch that has reached the conduction voltage, so that the second switch remains in the conduction state during the pre-charge stage, so that the pre-charge branch corresponding to the second switch performs the pre-charge operation.

14. An electronic device, characterized in that, Includes a power supply, a power bus, a bus capacitor, and a power distribution module as described in any one of claims 12-13; The power supply is connected to the power supply port of the power distribution unit; The bus capacitor is connected to the power distribution port of the power distribution unit through the power bus.

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