WO2012083746A1

WO2012083746A1 - Distributed wireless power supply system for base station

Info

Publication number: WO2012083746A1
Application number: PCT/CN2011/080576
Authority: WO
Inventors: 唐倬; 曹喜; 莫少勇
Original assignee: 华为技术有限公司
Priority date: 2011-10-09
Filing date: 2011-10-09
Publication date: 2012-06-28
Also published as: CN102439835A

Abstract

Provided is a distributed wireless power supply system for a base station, which relates to the field of wireless communication and includes: a battery, an AC to DC converter, a busbar, a power distribution unit used for distributing electric energy, a remote cable, and a load; the power distribution unit includes a voltage boosting circuit and a first switch; the battery is connected with the converter in parallel by means of an input terminal of the busbar, with the output terminal of the busbar connected to an input terminal of the voltage boosting circuit, wherein an output terminal of the voltage boosting circuit is connected to an input terminal of the first switch, with the output terminal thereof connected to an input terminal of the remote cable, and an output terminal of the remote cable is connected to the load; the voltage boosting circuit has a boosting setpoint, and the voltage boosting circuit stops working when the voltage of the busbar is higher than or equal to the boosting setpoint and starts working when the voltage is less than the boosting setpoint. By means of the solution in the present invention, in the case where the power is supplied by a battery, the cross-section of the cable and the height of the power distribution unit can be reduced, and the material cost of the cable is decreased, the remote distance of the cable is increased and the life of the RRU is prolonged.

Description

Wireless distributed base station power supply system

The present invention relates to the field of wireless communications, and in particular, to a wireless distributed base station power supply system. Background art

In a wireless distributed base station power supply system, the power supply needs to be remotely transmitted to the RRU (Remote Radio Unit) to supply power thereto.

The existing wireless distributed base station power supply system includes: a battery, an AC to DC converter, a bus bar, a power distribution unit for distributing power, a remote cable, and an RRU, wherein the battery pool and the AC to DC The converter is connected in parallel through the input end of the bus bar, and the output end of the bus bar is connected to the input end of the switch in the power distribution unit, the output end of the switch is connected to the input end of the cable, and the output end of the cable is connected to the RRU.

When the AC power is normal, the AC power is converted to a DC output by a converter that is AC-to-DC. The RRU is supplied to the RRU through the switch and the remote cable, and the battery is also floated. When the power is cut off, the AC to DC converter is turned off, and the battery is discharged to supply power to the RRU. When the battery is discharged for a period of time, the output voltage of the battery terminal gradually decreases. When the battery terminal voltage drops to 43V, the system will cut off the battery discharge circuit and stop supplying power to the RRU.

Since the minimum output voltage U _3⁄4IN of the bus bar is the battery terminal voltage 43V when the battery is powered off, and the lowest input voltage Ub _MIN of the RRU is a fixed value, usually 36V, therefore, the maximum allowable voltage on the remote cable Drop to AU _MX = Ua-Ub=7V „ Take copper wire as an example, R=2 XL/57S= AUX Ub/P. It can be seen that: (1) in the distance (L) and RRU power ( P) Keeping the same, because the output voltage of the battery terminal is gradually reduced, the AU is reduced, the cable cross section becomes larger, the material cost is increased, and as the cable cross section increases, the height dimension of the power distribution unit is also increased. (2) When the RRU power (Ρ) remains unchanged, the maximum distance (A) is limited by AU _x = 7V, and the cable's distance (L) is also limited. (3) Due to the RRU input side Electrolytic capacitors, the battery voltage is constantly getting lower under the battery power supply, the current on the cable is continuously increased, and the voltage drop AU on the cable is continuously increased. The working mode of the RRU107 is not transmitting power (static). And switching between transmit power (dynamic), and frequency High, the current on the cable leading to the rapidly changing, such that the voltage drop on the cable remote constantly fluctuating, resulting ripple current in the electrolytic capacitor life and reduce the service life of electrolytic capacitors RRU.

In the case of battery power supply, there is no corresponding problem in the prior art due to the problem that the cable cross section becomes large due to the low battery voltage, the power distribution unit height dimension increase port, the cable pull distance is limited, and the RRU life is reduced. solution. Summary of the invention

The present invention provides a wireless distributed solution in order to solve the problem that the cable cross-section becomes large due to the low battery voltage, the height of the power distribution unit is increased, the distance of the cable is limited, and the RRU life is reduced. Base station power supply system. The technical solution is as follows:

A wireless distributed base station power supply system, the system comprising: a battery, an AC to DC converter, a bus bar, a power distribution unit for distributing electrical energy, a remote cable, and a load; the power distribution unit includes: a booster circuit and a first switch;

The battery and the AC to DC converter are connected in parallel through an input end of the bus bar, an output end of the bus bar is connected to an input end of the boost circuit, and an output end of the boost circuit is connected to the An input end of the first switch, an output end of the first switch is connected to an input end of the remote cable, an output end of the remote cable is connected to the load; and the boost circuit has a boosting a fixed point, when the voltage of the bus bar is higher than or equal to the boosting set point, the boosting circuit is inactive, in a through state, when the voltage of the bus bar is lower than the boosting set point, The boost circuit begins to operate.

The beneficial effects of the technical solutions provided by the embodiments of the present invention are:

By adding a boosting circuit to the wireless distributed base station power supply system, when the battery voltage becomes lower and the voltage of the bus bar is lower than a certain value, the boosting circuit starts to work to increase the voltage of the bus bar to a set value, thereby ensuring the bus bar. In any case, the output voltage is not less than the system setting value, which reduces the cable section and the height dimension of the power distribution unit, reduces the material cost of the cable, increases the cable's distance, and extends the RRU life. DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly described. It is obvious that the drawings in the following description are only some embodiments of the present invention. Other drawings may also be obtained from those of ordinary skill in the art in view of the drawings.

1 is a schematic structural diagram of a wireless distributed base station power supply system according to an embodiment of the present invention;

FIG. 2 is another schematic structural diagram of a wireless distributed base station power supply system according to an embodiment of the present invention; FIG. 3 is another schematic structural diagram of a wireless distributed base station power supply system according to an embodiment of the present invention; The schematic diagram of the circuit structure of the booster circuit and the first switch provided by the embodiment of the invention. detailed description

The embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

Referring to FIG. 1, an embodiment of the present invention provides a wireless distributed base station power supply system, including: a battery 101, an AC to DC converter 102, a bus bar 103, a power distribution unit 104 for distributing power, and a remote The cable 105 and the load 107; the power distribution unit 104 includes: a booster circuit 108 and a first switch 106; the battery 101 and the AC to DC converter 102 are connected in parallel through the input terminal of the bus bar 103, and the output of the bus bar 103 is connected. The output end of the boosting circuit 108 is connected to the input end of the first switch 106, the output end of the first switch 106 is connected to the input end of the remote cable 105, and the output end of the remote cable 105 is connected. The boosting circuit 108 has a boosting setting point. When the voltage of the bus bar 103 is higher than or equal to the boosting set point, the boosting circuit 108 does not operate, and is in a through state, when the voltage of the bus bar 103 is lower than the rise. When the fixed point is pressed, the booster circuit 108 starts operating.

It should be noted that when power is supplied to n loads, 0 is a natural number of ≡3⁄4, and the output of the bus bar 103 is allocated as n branches, and each branch includes a boost circuit, a first switch, and a remote line. Cable, and load, see Figure 1 for the connections of the components in each branch.

Referring to FIG. 2, further, the wireless distributed base station power supply system may further include: a second switch 109, the second switch 109 is connected in parallel with the boosting circuit 108; when the voltage of the bus bar 103 is higher than or equal to the boosting set point, the second The switch 109 is closed, the boosting circuit 108 is inactive, and is in a through state. When the voltage of the bus bar 103 is lower than the boosting set point, the second switch 109 is turned off, and the boosting circuit 108 starts operating.

It should be noted that when power is supplied to n loads, n is a natural number, and the output of the bus bar is allocated as n branches, each of which includes a boost circuit, a first switch, a remote cable, and a load. And the second switch, the connection of each component in each branch is shown in Figure 2.

The first switch 106 or the second switch 109 may be an electrical device circuit breaker, or may be a MOSTEKMetal Oxid Semiconductor Field Effect Transistor, an IGBT (Insulated Gate Bipolar Transistor), an insulated gate bipolar transistor. ) Power semiconductor switching elements.

It should be noted that, if the wireless distributed base station power supply system has n branches, for the embodiment shown in FIG. 1, each branch includes a first switch 106, and the first of each path i Switch 106 is shown as QFi. For example, first switch 106 of the first branch is represented as QF1, and first switch 106 of the nth branch is represented as QFn. If the wireless distributed base station power supply system has n branches, for the embodiment shown in FIG. 2, each branch includes a first switch 106 and a second switch 109, and the first of each branch i A switch 106 is shown as QFi, and a second switch 109 in each branch i is represented as Si. For example, the second switch 109 of the first branch is represented as S1, and the second switch 109 of the nth branch is represented as Sn.

The load 107 can be a radio remote unit RRU, and an input capacitor of the RRU is connected to an electrolytic capacitor. Need to explain Yes, if the wireless distributed base station power supply system has n branches, that is, there are n ■ (ie, RRUU R rats..., RRUn), there are corresponding n electrolytic capacitors (Cl, C-2, ..., Cn).

The booster circuit 108 may be a circuit having a boost function such as B00ST, BUCK-BOOST, CUK, etc., and the specific implementation circuit is not limited in this embodiment. When the booster circuit 108 is a BOOST circuit, the booster circuit 108 is composed of an inductor L, a first MOSFET tube Q, a first diode D, and a first capacitor C; one end of the inductor L and the source of the first MOSFET tube Q The other end of the inductor L is the negative input terminal of the booster circuit 108, the source of the first MOSFET tube Q is the positive input terminal of the booster circuit 108, the source of the first MOSFET tube Q and the first diode D The negative pole is connected, the drain of the first MOSFET tube Q is connected to one end of the first capacitor C, the other end of the first capacitor C is connected to the anode of the first diode D, and the two ends of the first capacitor C are boost circuits The output of 108.

It should be noted that if the wireless distributed base station power supply system has n branches, each branch includes a boosting circuit 108, and the composition of the boosting circuit 108 in each of the paths i is represented as an inductance Li, The first MOSFET tube Qi, the first diode Di, and the first capacitor Ci, for example, for the first branch, the composition of the boosting circuit 108 is represented as an inductor L1, a first MOSFET tube Q1, and a first diode D1. And a first capacitor C1. For the nth branch, the composition of the boosting circuit 108 is represented by an inductor Ln, a first MOSFET tube Qn, a first diode Dn, and a first capacitor Cn.

According to the description of the structure of the load 107 and the booster circuit 108, the specific structure of the wireless distributed base station power supply system is shown in FIG. It should be noted that Figure 3 shows n branches.

Further, the combination of the boosting circuit 108 and the first switch 106 may further include: a second capacitor C', a second diode D', and a varistor RV; the first switch 106 is a second MOSFET tube Q' For example, the circuit structure of the booster circuit 108 and the first switch 106 is integrated as shown in FIG. 4: one end of the second capacitor C' is connected to the cathode of the second diode D', and the other end of the second capacitor C' is The source of the second MOSFET tube Q' is connected, the drain of the second MOSFET tube Q' is connected to the anode of the second diode D', and the cathode of the second diode D' is connected to the anode input terminal of the booster circuit 108. The anode of the second diode D' is connected to the negative input terminal of the booster circuit 108, and the output terminal of the booster circuit 108 is connected to the varistor RV.

In this embodiment, the minimum output voltage Uc of the power distribution unit is greatly increased by the booster circuit, and the maximum voltage drop allowed on the remote cable is AU=Uc - Ub _MIN is also greatly increased. Taking a copper wire as an example, R =2 XL/57S= AUX Ub/P, which shows: (1) In the case where the distance (L) and the RRU power (P) remain unchanged, the increase in Δ U can reduce the cable cross-sectional area (S). The height dimension of the power distribution unit is also reduced accordingly, which saves a lot of material costs. (2) In the case where the cable cross-sectional area (S) and the RRU power (P) remain unchanged, the increase in AU can increase the distance (L) of the cable and increase the distance of the cable. (3) Since the minimum output voltage Uc of the power distribution unit is greatly increased, the RRU input voltage Ub is also greatly improved. Under the conditions of the long distance (L), the cable cross-sectional area (S) and the RRU power (P), The AU becomes smaller, so that the voltage fluctuation of the RRU on the cable is also reduced when the RRU is switched, thereby reducing the ripple current flowing into the electrolytic capacitor and improving the ripple current. The life of the electrolytic capacitor increases the service life of the RRU accordingly. A person skilled in the art may understand that all or part of the steps of implementing the above embodiments may be completed by hardware, or may be instructed by a program to execute related hardware, and the program may be stored in a computer readable storage medium. The storage medium mentioned may be a read only memory, a magnetic disk or an optical disk or the like. The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., which are within the spirit and scope of the present invention, should be included in the protection of the present invention. Within the scope.

Claims

Claim

A wireless distributed base station power supply system, characterized in that: the system comprises: a battery, an alternating current to direct current converter, a bus bar, a power distribution unit for distributing electrical energy, a remote cable, and a load; The power distribution unit includes: a booster circuit and a first switch;

The battery and the AC to DC converter are connected in parallel through an input end of the bus bar, an output end of the bus bar is connected to an input end of the boost circuit, and an output end of the boost circuit is connected to the An input end of the first switch, an output end of the first switch is connected to an input end of the remote cable, an output end of the remote cable is connected to the load; and the boost circuit has a boosting a fixed point, when the voltage of the bus bar is higher than or equal to the boosting point, the boosting circuit is inactive, in a through state, when the voltage of the bus bar is lower than the boosting point, The boost circuit begins to operate.

2. The system according to claim 1, wherein the power distribution unit further comprises: a second switch, wherein the second switch is connected in parallel with the boosting circuit;

When the voltage of the bus bar is higher than or equal to the boosting point, the second switch is closed, and when the voltage of the bus bar is lower than the boosting point, the second switch is disconnected .

The system according to claim 1 or 2, wherein the boosting circuit is composed of an inductor L, a first MOSFET, a first diode, and a first capacitor;

One end of the inductor L is connected to the source of the first MOSFET, the other end of the inductor L is a negative input terminal of the booster circuit, and the source of the first MOSFET is the booster circuit a positive input terminal, a source of the first MOSFET is connected to a negative terminal of the first diode, and a drain of the first MOSFET is connected to one end of the first capacitor, the first capacitor The other end of the first capacitor is connected to the anode of the first diode, and the two ends of the first capacitor are the output ends of the booster circuit.

The system of claim 3, wherein the first switch is a second MOSFET, the system further comprising: a second capacitor, a second diode, and a varistor;

One end of the second capacitor is connected to a cathode of the second diode, the other end of the second capacitor is connected to a source of the second MOSFET, and a drain of the second MOSFET is The second diode is connected to the positive pole, the cathode of the second diode is connected to the positive input terminal of the booster circuit, and the anode of the second diode is connected to the negative input terminal of the booster circuit. An output of the booster circuit is coupled to the varistor.

The system according to claim 1, wherein the load is a radio remote unit, and an input side of the radio remote unit is connected to an electrolytic capacitor.