TWI767280B - Method for reducing line loss of power supply system and power supply system with reduced line loss - Google Patents

Abstract

A power supply system with reduced line loss supplies power to a load through a power line, and includes a boost converter, a detection circuit and a control unit. The control unit sets a terminal voltage required by the load and controls an output voltage of the boost converter to be the terminal voltage, and an output current corresponding to the terminal voltage detected by the detection circuit is a currently current. The control unit controls the output voltage of the boost converter to be an adjustment voltage, and the corresponding output current detected by the detection circuit is an adjustment current. The control unit adjusts the output voltage of the boost converter to a first predetermined voltage according to the terminal voltage, the currently current, the adjustment voltage and the adjustment current.

Description

Method for reducing line loss of power supply system and power supply system with reduced line loss system

The present invention relates to a method for reducing line loss of a power supply system and a power supply system with reduced line loss, in particular to a method for reducing line loss of a power supply system without measuring the impedance of a power line.

A base station usually includes a Baseband Unit (BBU), a Remote Radio Unit (RRU) and one or more antenna modules. In 5G applications, the RF module and the antenna module can also be integrated It is an Active Antenna Unit (AAU). Whether it is RRU or AAU, it usually needs to be installed in a higher place to facilitate the transmission and reception of signals. Therefore, communication equipment such as RRU/AAU is usually erected at the highest place by using an electric tower. At present, there is a certain distance between the power supply system and the load on the tower. This distance will bring about a certain degree of power loss and voltage drop in power line transmission. Especially in the 5G system, the power of the equipment on the tower will increase. Therefore, the power loss and voltage drop during transmission cannot be ignored, and it is necessary to think about how to reduce the power transmission loss.

Using a higher voltage for transmission will reduce power loss, but since it cannot affect the voltage of the base station equipment under the tower, a booster device will be added first, but it must be ensured that the load terminal voltage cannot exceed the maximum allowable voltage of the equipment. In a previous embodiment, a detector is installed on the load end of the tower to detect the voltage of the load end, and a communication device is used to communicate with the power supply system of the base station. When the load current is large, the output voltage of the power supply system is increased to maintain the voltage of the load end, and then This method increases the difficulty and cost of construction, and has the possibility of communication failure. Another way is to install another step-down device on the tower to convert the voltage transmitted to the tower to the voltage of the equipment on the tower, but its disadvantage is the loss of multiple step-down devices, and because the step-down device is located in the electrical tower. On the tower, causing maintenance difficulties. There is also another possible way to input the length, thickness and other information of the power line in advance, so as to estimate the impedance of the power line, and then compensate the voltage according to the output current. However, the problem with this method is that the impedance of the power line will change due to aging, or the re-installation will not be immediate. Updating the information can easily cause voltage compensation errors and damage the equipment.

Therefore, how to design a method for reducing line loss of a power supply system and a power supply system with reduced line loss, using special voltage compensation calculation steps and methods to accurately and quickly calculate the adjustment required to meet the needs of communication equipment The voltage of the power supply equipment is a major problem that the creator of this project intends to overcome and solve.

In order to solve the above problems, the present invention provides a method for reducing line loss of a power supply system to overcome the problems of the prior art. Therefore, the power supply system of the present invention includes a boost converter, and the boost converter provides a load voltage to the load through a power line, and the method for reducing line loss includes the following steps: setting a terminal voltage required by the load, and controlling the output of the boost converter The voltage is the terminal voltage. Detect terminal voltage The corresponding output current is the current current. The control output voltage is the modulation voltage, and the detected corresponding output current is the modulation current. The output voltage of the boost converter is adjusted to a first predetermined voltage according to the terminal voltage, the current current, the modulated voltage and the modulated current. Wherein, the load voltage obtained by deducting the voltage drop of the power line from the first predetermined voltage satisfies the preset terminal voltage.

In order to solve the above problems, the present invention provides a power supply system with reduced line loss to overcome the problems of the prior art. Therefore, the power supply system of the present invention provides the load with the load voltage through the power line, and the power supply system includes: a boost converter, which receives the input voltage from the input terminal, and supplies the load with the output voltage provided by the output terminal. The detection circuit is coupled to the output end. and a control unit, which is coupled to the boost converter and the detection circuit, and controls the boost converter to convert the input voltage into the output voltage. The control unit sets the terminal voltage required by the load, and the voltage at the control output terminal is the terminal voltage; the control unit detects the output terminal through the detection circuit and obtains the output current corresponding to the terminal voltage as the current current; the control unit controls the output terminal voltage as The voltage is modulated, and the output current corresponding to the modulated voltage is obtained by detecting the output terminal through the detection circuit as the modulated current; the control unit adjusts the output voltage according to the terminal voltage, the current current, the modulated voltage and the modulated current to be the first The predetermined voltage is such that the load voltage obtained by deducting the voltage drop of the power line from the predetermined voltage satisfies the terminal voltage preset by the control unit.

The main purpose and effect of the present invention is that the voltage drop of the power line can be obtained without adding conversion equipment, impedance measurement equipment or additional communication devices through the above-mentioned special line loss reduction steps and processes in this case, and can The effect of quickly calculating the voltage to be adjusted can increase the voltage of the load input terminal to reduce the transmission loss of the power line, and also ensure that the load input terminal voltage will not exceed the maximum allowable operating value of the equipment under different load conditions.

In order to further understand the technology, means and effect adopted by the present invention to achieve the predetermined purpose, please refer to the following detailed description and accompanying drawings of the present invention. It is believed that the purpose, features and The characteristics can be understood in depth and specific, but the accompanying drawings are only provided for reference and description, and are not used to limit the present invention.

100: Power supply system

10: Rectifier unit

20: Boost Converter

22: Input terminal

24: output terminal

30: Detection circuit

40: Control unit

50: Bypass switch

60: DC Converter

60-1: Renewable Energy

70: battery

200: Powerline

300: load

A: Electric tower

Vac: AC voltage

Vin: input voltage

Vo: output voltage

Vr: power line voltage drop

Vl: terminal voltage

Iin: input current

Io: output current

Sin: input signal

So: output signal

Sc1: The first control signal

Sc2: The second control signal

1 is a system structure diagram of a power supply system with reduced line loss according to the present invention; FIG. 2 is a circuit block diagram of a power supply system with reduced line loss according to the present invention; and FIG. 3B is a flow chart of the steps of the subsequent circuit adjustment of the method for reducing line loss of the power supply system of the present invention.

The technical content and detailed description of the present invention are described as follows in conjunction with the drawings: Please refer to FIG. 1 , which is a system architecture diagram of a power supply system with reduced line loss of the present invention. The power supply system 100 is mainly used in an environment where the power line 200 is used to couple the load 300 and the power supply system 100 and the load 300 have a long distance. Taking the electrical tower A in FIG. 1 as an example, the power supply system 100 is arranged under the electrical tower A, and the load 300 is arranged on the electrical tower A. As shown in FIG. The load 300 is a device with large power consumption, such as, but not limited to, a 5G communication device. Since the power line 200 connected to the load 300 needs to be pulled down from the power tower A to the power tower A, the loss of the power line 200 is very significant. Therefore, the output voltage of the power supply system 100 under the power tower A will be different from the load on the power tower A. The voltage received by the 300 has a large drop. When the current drawn by the load 300 is relatively large, the voltage difference may even exceed ten volts, and the larger the current flowing through the power line 200, the larger the line loss will be. Therefore, when the load 300 is a device that consumes a large amount of power, it is very important to reduce the loss of the power line 200 .

Please refer to FIG. 2 , which is a circuit block diagram of the power supply system with reduced line loss according to the present invention. Please refer to FIG. 1 again. The power supply system 100 under the tower A supplies power to the load 300 on the tower A through the power line 200 . The input end 22 of the boost converter 20 is coupled to the rectifier unit 10 , and the output end 24 is coupled to the load 300 through the power line 200 . The rectifying unit 10 receives the AC voltage Vac, and rectifies the AC voltage Vac into the input voltage Vin. The boost converter 20 receives the input voltage Vin, and converts the input voltage Vin into the output voltage Vo under the control of the control unit 40 . The power line 200 receives the output voltage Vo, and after passing through the power line voltage drop Vr of the power line, a load voltage V1 is provided to the load 300 at the terminal of the power line. Due to the influence of the voltage drop Vr of the power line, the voltage value of the load voltage Vl will be smaller than the voltage value of the output voltage Vo.

The detection circuit 30 is coupled to the output terminal 24 of the boost converter 20 and used to detect the output voltage Vo and the output current Io of the output terminal 24 . The detection circuit 30 provides the output signal So to the control unit 40 according to the magnitudes of the output voltage Vo and the output current Io, so that the control unit 40 can know the magnitudes of the output voltage Vo and the output current Io. The control unit 40 receives the output signal So, and provides the first control signal Sc1 to the boost converter 20 according to the output signal So, so as to adjust and stabilize the voltage value of the output voltage Vo to a predetermined voltage value. The boost converter 20, the detection circuit 30 and the control unit 40 can be integrated into a power supply, and the control unit 40 is a power control processor of the power supply.

Referring back to FIG. 2 , the power supply system 100 under the tower further includes a bypass switch 50 , a DC converter 60 , a renewable energy source 60 - 1 and a battery 70 . The bypass switch 50 is connected in parallel with the boost converter 20 (ie, one end is coupled to the input end 22 and the other end is coupled to the output end 24 ), and is coupled to the control unit 40 . The bypass switch 50 is turned on by the second control signal Sc2 provided by the control unit 40 to bypass the boost converter 20 so that the power supply system 100 does not provide the boost function. The DC converter 60 can be connected to another backup power source (such as but not Limited to the renewable energy 60-1) to output DC voltage, such as connecting renewable energy such as solar energy and wind power, the DC converter 60 can be selectively set according to the system requirements, or can be connected to other backup energy in different configurations. The battery 70 is coupled to the input terminal 22 of the boost converter 20 , and provides the input power Vin to power the boost converter 20 when the AC voltage Vac is not present or the DC converter 60 has no output. Among them, the input power Vin is mainly used to provide the voltage required by the base station equipment under the tower, including other base station equipment such as the baseband unit (not shown).

Please refer to FIG. 3A for a flow chart of the steps of the method for reducing line loss in the power supply system of the present invention, and refer to FIGS. 1-2 in combination. Since the reduction of line losses must be considered from the overall efficiency of the entire power supply system 100, the addition of a boost converter 20 or even a buck converter must be added to the tower A, the efficiency of these converters will affect the entire power supply. System 100 efficiency has a degrading effect. Therefore, the improvement of the transmission power loss of the power line 200 cannot be looked at alone, and the influence of these parameters on the overall efficiency must be comprehensively considered. Further, under different load conditions, there will be different adjustment mechanisms. In addition, the adjustment of the output voltage Vo needs to consider the influence of these parameters on the overall efficiency when the AC voltage Vac is present. When there is no AC voltage Vac, the power source is supplied by the battery 70. Therefore, the battery of the battery 70 must also be adjusted. The effect of capacity addition and the above parameters on the overall efficiency. Therefore, there are too many factors to consider in the adjustment of the output voltage Vo, which must be determined according to the efficiency and requirements of the overall power supply system 100 .

Therefore, the present invention proposes a special method for reducing line loss. The method firstly includes: setting the terminal voltage required by the load, controlling the output voltage of the boost converter to be the terminal voltage, and detecting the corresponding output current as the current current; obtaining the first output power by the product of the terminal voltage and the current current ( S100). The detection circuit 30 detects the output terminal 24 of the boost converter 20 to obtain the output signal So, and the control unit 40 can control the output voltage of the boost converter to the terminal voltage by receiving the output signal So, which is the general feedback control principle , and at the same time can detect the corresponding output current as the current current. Then, control The control unit 40 obtains the first output power provided by the boost converter 20 at this time through the product of the terminal voltage and the current current. Since the first output power provided by the boost converter 20 at this time will be equal to the power consumed by the power line 200 at this time plus the power consumed by the load 300, it can be expressed as: Vo1×Io1=Vr1×Io1+Vl1×Io1 . Among them, Vo1 represents the current output voltage of the boost converter, and the output voltage at this time is the terminal voltage set by the control unit, Io1 represents the current current, Vr1 represents the current power line voltage drop (ie the first voltage drop), and Vl1 represents the current load Voltage.

Then, the output voltage of the boost converter is controlled to be the modulated voltage, and the corresponding output current is detected to be the modulated current, so as to obtain the second output power by multiplying the modulated voltage and the modulated current ( S200 ). The control unit 40 modulates the output voltage Vo by controlling the boost converter 20 to adjust the output voltage to a modulated voltage (ie, to change the voltage value of the output voltage Vo). The control unit 40 can control the output voltage of the boost converter to be the modulated voltage by receiving the output signal So, and simultaneously detect the corresponding output current as the modulated current. Then, the control unit 40 calculates the second output power provided by the boost converter 20 at this time through the product of the modulation voltage and the modulation current. Since the second output power provided by the boost converter 20 at this time is also equal to the power consumed by the power line 200 at this time plus the power consumed by the load 300, it can be expressed as: Vo2×Io2=Vr2×Io2+Vl2× Io2. Among them, Vo2 represents the modulation voltage, Io2 represents the modulation current, Vr2 represents the voltage drop of the power line after modulation, and Vl2 represents the load voltage at this time.

Then, the power difference is obtained by subtracting the first output power and the second output power, and the power line voltage drop of the power line is obtained as the first voltage drop according to the power difference, the current current and the modulated current ( S300 ). In theory, under the condition that the power of the load 300 remains unchanged, the power of the load 300 before modulation will be equal to the power of the load 300 after the modulation, that is, Vl1×Io1=Vl2×Io2. In this way, the current power line voltage drop can be obtained as Vr1=ΔP×Io1/(Io1 ² −Io2 ² ). Wherein, ΔP is the power difference between the first output power and the second output power, which can be obtained by subtracting the first output power and the second output power. Therefore, when the power difference, the current current and the modulated current are known, the current power line voltage drop (ie, the first voltage drop) can be obtained. Through the above steps and processes, the present invention can obtain the voltage drop of the power line without measuring the impedance of the power line 200 . Among them, in order to prevent the power of the load 300 from changing during the modulation process of the output voltage Vo, the power of the load 300 before the modulation is not equal to the power of the load 300 after the modulation (this situation will cause the calculated value of the first voltage drop not the correct value). Therefore, the control unit 40 can set a confirmation mechanism to avoid the above situation from happening. That is, after the output voltage Vo of the boost converter 20 is adjusted from the terminal voltage to the modulation voltage, the control unit 40 adjusts the output voltage Vo back to the terminal voltage, and then uses the product of the terminal voltage and the output current Io at this time to obtain The output power at this time is to confirm whether the output power at this time is within the error range of the first output power, or, the output current Io at this time is detected as the confirmation current, and it is determined whether the confirmation current is within the current current Io1 detected previously. The error range can be selected according to the design requirements, such as but not limited to 3%. When the current output power or output current is within the error range, it means that the power of the load 300 is approximately or equal to maintaining the original value, and the calculated first voltage drop is an accurate value. On the contrary, it means that the power of the load 300 has changed, and the calculated first voltage drop is not an accurate value.

Finally, the output voltage of the boost converter is adjusted to a first predetermined voltage through the first voltage drop and the terminal voltage (S400). In step (S300), the current power line voltage drop (ie, the first voltage drop) has been obtained. Since the load power is approximately unchanged, it can be obtained under this condition, how much the voltage value of the output voltage Vo needs to be adjusted, and the load 300 The input terminal (load voltage) will be exactly equal to the set terminal voltage. Since the output voltage of the boost converter is adjusted, the corresponding output current will change, and the voltage drop of the power line will also change at the same time, so it is not necessary to directly add the obtained first voltage drop Vr1 and Vo1. The control unit 40 can obtain the adjusted output voltage Vo(set) (ie, the first predetermined voltage) by adding the terminal voltage Vo1 to the compensation amount of the power line voltage drop Vr1 in response to the current change. The above description is represented by the formula Vo(set)=Vo1+Vr1×(Vo1−Vr1)/Vo1, where Vo(set) is the first predetermined voltage. The control unit 40 according to the above steps After obtaining the first predetermined voltage, the output voltage Vo of the boost converter 20 is adjusted to the first predetermined voltage through the first control signal Sc1, so that the first predetermined voltage is transmitted to the input of the load 300 by deducting the loss of the power line 200 When the terminal is at the terminal, the voltage of the input terminal of the load 300 is exactly equal to the terminal voltage Vo1 preset by the control unit 40 . Therefore, the main purpose of the present invention is that, through the above steps and processes, the voltage and current output by the boost converter 20 can be measured according to the measurement circuit 30 without adding a conversion device or an impedance measurement device. The voltage drop of the power line 200 can be obtained without additionally obtaining and confirming the impedance of the power line 200 and the voltage at the input end of the load 300 , thus achieving the effect of accurately and quickly calculating the voltage to be adjusted without additional circuit cost. .

In short, the main purpose of the above steps is that due to the voltage drop of the power line 200 , it is desirable that the output voltage be as high as possible to reduce the transmission current and thus the loss, but cannot exceed the maximum allowable voltage of the equipment on the tower. The terminal voltage required by the load is preset by the control unit 40, and the output voltage of the boost converter is controlled to be the terminal voltage and the modulation voltage, and the corresponding currents are detected respectively, so as to obtain when the output voltage is the terminal voltage. The power line voltage drop (ie the first voltage drop). In this way, how to adjust the output voltage of the boost converter can be quickly obtained, and the voltage at the input end of the load can be maintained at the set terminal voltage value, which has the advantage of being fast and accurate.

Please refer to FIG. 3B for a flow chart of the steps of the subsequent circuit adjustment of the method for reducing line loss of the power supply system of the present invention, and refer to FIGS. 1 to 3A in combination. After the control unit 40 adjusts the output voltage Vo of the boost converter 20 to the first predetermined voltage, the output current Io at this time is the first predetermined current. When the load power of the load 300 changes, due to the influence of the power line voltage drop Vr on the power line 200, the voltage value of the load voltage V1 also changes accordingly and is no longer equal to the set terminal voltage. Therefore, when the load power of the load 300 changes, the control unit 40 must adjust the voltage value of the output voltage Vo to respond to the change of the load power. It can obtain the final adjustment value of the output voltage Vo through the following steps: when negative When the load power of the load changes so that the first predetermined current changes to the first changing current Io3, the second voltage drop Vr3 is obtained according to the first voltage drop, the first changing current Io3 and the current current Io1, and according to the second voltage drop Vr3, The terminal voltage Vo1 and the first predetermined voltage Vo(set) are used to adjust the output voltage to the second predetermined voltage (S500).

Specifically, when the load power changes, the current value of the output current Io will change (that is, from the first predetermined current to the first changing current Io3 ), and because the change of the output current Io is proportional to the power line voltage drop Vr Therefore, it can be obtained by the formula Vr3=Vr1×Io3/Io1 when the output current Io is the first changing current Io3 (obtained by the control unit 40 through the detection circuit 30 ), the change of the power line voltage drop Vr (that is, the change in the voltage drop Vr by the first changing current Io3 ) A voltage drop Vr1 is obtained as a second voltage drop Vr3). Wherein, Vr3 in the above formula is the second voltage drop, Io3 is the first changing current, and Io1 is the current current corresponding to the first voltage drop. Since the output voltage Vo of the boost converter 20 is the first predetermined voltage Vo(set) at this time, and the voltage drop of the power line becomes the second voltage drop Vr3, the aforementioned formula Vo(set)=Vo1+Vr1×(Vo1 -Vr1)/Vo1 is replaced to determine a new predetermined value of the output voltage Vo (ie, the second predetermined voltage Vo(set2)). The formula of the second predetermined voltage Vo(set2) is Vo(set2)=Vo1+Vr3×(Vo(set)−Vr3)/Vo1. The second predetermined voltage is obtained in the above manner, so that when the load power changes, the voltage value of the load terminal can still be maintained as the preset terminal voltage Vo1. When the subsequent load power continues to change, the same control method is adopted. For example, if the output current Io continues to change from the first changing current Io3 to the second changing current Io4, then the third voltage drop Vr4 can also be known as Vr4=Vr1× Io4/Io1, according to the aforementioned principle, the output voltage Vo can be adjusted to the third predetermined voltage Vo(set3) at this time, and the formula of the third predetermined voltage Vo(set3) is Vo(set3)=Vo1+Vr4×(Vo(set2 )-Vr4)/Vo1, so as to ensure that the load terminal voltage is the preset terminal voltage Vo1, and the following load changes all use the same replacement iteration principle, which will not be repeated.

Referring to FIG. 2 , in some special cases, the control unit 40 will provide the second control signal Sc2 to control the bypass switch 50 to be turned on, so as to bypass the boost converter 20 . Specifically, since the boost The converter 20 has different conversion efficiencies at different loads. Taking every 10% of the load as a point, the load is from 10% to 100%, a total of 10 points. The load may be the lowest at 10% efficiency, and from 10% to 40% efficiency shows an upward trend, usually at 50% efficiency point, and then 60% to 100% efficiency shows a downward trend. Therefore, when the load is not high, the conversion efficiency of the boost converter 20 is poor, resulting in a large power loss, and because the load is not high, the current is relatively small, and the loss on the power line is not large. The bypass switch 50 is turned on, saving losses in the boost converter. Therefore, the control unit 40 calculates how much the output voltage Vo needs to be adjusted, and can obtain how much the power line power loss is reduced, as well as the power loss of the boost converter 20 under this condition. In this way, the control unit 40 can determine whether to execute the boost mode or the bypass mode, so as to obtain the highest efficiency of the entire system.

The highest efficiency of the entire system can be confirmed by: confirming the conversion efficiency of the boost converter to obtain increased losses; evaluating the power line losses if the boost converter is bypassed, that is, directly supplying the input voltage Vin to the power line 200 The resulting power line losses; determine the boost converter and power line losses when the boost converter is boosting. Through these losses, the control unit 40 can determine whether to perform the boost mode or the bypass mode to obtain the highest efficiency of the entire system.

The following is an example of possible implementations of each loss, but it is not limited to this. The conversion efficiency of the boost converter can be known by the built-in pre-measurement of the conversion efficiency of each load, or by real-time detection of the boost converter. The input and output power of the boost converter under a specific load is known. The power line loss when the boost converter is bypassed, since the input voltage Vin, the terminal voltage Vo1, the power line voltage drop at this time and the first predetermined current at this time are all known, which is equivalent to the known load power consumption at this time, control The unit can calculate the power line loss when the boost converter is bypassed. For example, the control unit can use the Newton iteration method to solve the current when bypassing, so as to know the power line loss. If the boost converter boosts the voltage, the loss of the boost converter and the power line can also be easily known. Taking the aforementioned first predetermined voltage as an example, according to Vo(set)=Vo1+ Vr1×(Vo1−Vr1)/Vo1, it can be known that the power line loss at this time is equal to the product of the first predetermined current at this time and the current power line voltage drop (Vr1×(Vo1−Vr1)/Vo1).

In addition, another embodiment can also use a simpler method to determine, while maintaining the load terminal voltage as the set terminal voltage, if the voltage difference between the input voltage and the output voltage of the boost converter is lower than the threshold, in other words, the output The voltage of the load terminal can be maintained equal to the set terminal voltage without being too high, which means that the load may be low at this time, and the control unit 40 can also enter the bypass mode to avoid the self-loss of the boost converter from being lower than the loss after boosting. The threshold value can be appropriately selected according to the efficiency curve of the boost converter.

However, the above descriptions are only the detailed descriptions and drawings of the preferred embodiments of the present invention, but the features of the present invention are not limited thereto, and are not intended to limit the present invention. The scope of the patent shall prevail, and all embodiments that are consistent with the spirit of the scope of the patent application of the present invention and similar variations thereof shall be included in the scope of the present invention. Anyone who is familiar with the art in the field of the present invention can easily think Changes or modifications can be covered by the following patent scope of the present case.

100: Power supply system

10: Rectifier unit

20: Boost Converter

22: Input terminal

24: output terminal

30: Detection circuit

40: Control unit

50: Bypass switch

60: DC Converter

60-1: Renewable Energy

70: battery

200: Powerline

300: load

Vac: AC voltage

Vin: input voltage

Vo: output voltage

Vr: power line voltage drop

Vl: load voltage

Iin: input current

Io: output current

Sin: input signal

So: output signal

Sc1: The first control signal

Sc2: The second control signal

Claims (13)

A method for reducing line loss of a power supply system, the power supply system includes a boost converter, and the boost converter provides a load voltage to a load through a power line, the method for reducing line loss includes the following steps: setting the load to be a required terminal voltage, and control an output voltage of the boost converter to be the terminal voltage; detect an output current of the boost converter corresponding to the terminal voltage as a current current; control the boost converter The output voltage is a modulated voltage, and the output current of the boost converter corresponding to the modulated voltage is detected as a modulated current; a first output power is obtained by multiplying the terminal voltage and the current current; Obtain a second output power by multiplying the modulation voltage and the modulation current; obtain a power difference by subtracting the first output power and the second output power; and obtain a power difference according to the power difference, the terminal voltage, and the current current , the modulating voltage and the modulating current to adjust the output voltage of the boost converter to a first predetermined voltage; wherein, the load voltage after deducting a power line voltage drop of the power line from the first predetermined voltage satisfies the pre-set terminal voltage. The method for reducing line loss as described in claim 1, further comprising the following steps: obtaining the power line voltage drop as a first voltage drop according to the power difference, the current current, the modulated voltage and the modulated current voltage drop; the output voltage is adjusted to the first predetermined voltage through the first voltage drop and the terminal voltage. The method for reducing line loss as described in claim 1, wherein after the output voltage is adjusted from the terminal voltage to the modulated voltage, the output voltage is adjusted back to the terminal voltage to confirm that the terminal voltage is the same as the terminal voltage The product of the output current corresponding to the voltage is within an error range of the first output power. The method for reducing line loss as described in claim 2, wherein the first predetermined voltage satisfies: Vo(set)=Vo1+Vr1×(Vo1-Vr1)/Vo1, wherein Vo(set) is the first predetermined voltage The voltage, Vo1 is the terminal voltage, and Vr1 is the first voltage drop. The method for reducing line loss as described in claim 2, wherein when the output voltage is adjusted to the first predetermined voltage, the output current is a first predetermined current; when a load power of the load changes, the When the first predetermined current is changed to a first changing current, a second voltage drop is obtained according to the first voltage drop, the first changing current, and the current current, and a second voltage drop is obtained according to the terminal voltage, the first predetermined voltage and the The second voltage drop adjusts the output voltage to a second predetermined voltage. The method for reducing line loss as described in claim 5, wherein the second voltage drop satisfies: Vr3=Vr1×Io3/Io1, wherein Vr3 is the second voltage drop, Vr1 is the first voltage drop, and Io3 is the The first changing current, and Io1 is the current current. The method for reducing line loss as described in claim 1, wherein the output voltage is calculated as the first predetermined voltage under the condition that the load voltage is the predetermined terminal voltage when the output voltage is adjusted to the first predetermined voltage. When the first predetermined voltage is used, a first loss of the boost converter and the power line is calculated, and a second loss of the power line when the boost converter is bypassed is calculated; when the first loss is greater than or equal to the second loss , bypass the boost converter. The method for reducing line loss as described in claim 1 of the claimed scope, wherein when the output voltage is adjusted to the first predetermined voltage to satisfy the condition that the load voltage is the predetermined terminal voltage, when the boost converter is The boost converter is bypassed when a voltage difference between an input voltage and the output voltage is lower than a threshold. A power supply system with reduced line loss, which provides a load voltage to a load through a power line, the power supply system includes: a boost converter, an input terminal receives an input voltage, and an output terminal provides an output The load is powered by the voltage; a detection circuit is coupled to the output end; and a control unit is coupled to the boost converter and the detection circuit, and controls the boost converter to convert the input voltage into the output voltage; wherein, the control unit sets a terminal voltage required by the load, and controls the voltage of the output terminal to be the terminal voltage; the control unit detects the output terminal through the detection circuit to obtain the rise corresponding to the terminal voltage An output current of the voltage converter is a current current; the control unit controls the output voltage of the boost converter to be a modulation voltage, and detects the output terminal through the detection circuit to obtain the corresponding modulation voltage a modulating current; the control unit adjusts the output voltage to a first predetermined voltage according to the terminal voltage, the current current, the modulating voltage and the modulating current, so that the first predetermined voltage deducts a power line of the power line The load voltage after the voltage drop meets the terminal voltage preset by the control unit. The power supply system as described in claim 9, wherein after the output voltage is adjusted from the terminal voltage to the modulated voltage, the control unit adjusts the output voltage back to the terminal voltage The terminal voltage is detected, and the output current is detected as a confirmation current by the detection circuit; the control unit determines whether the confirmation current is within an error range of the current current. The power supply system as described in claim 9, wherein when the output voltage is adjusted to the first predetermined voltage, the output current is a first predetermined current; when the detection circuit detects the first predetermined current When changing to a first changing current, the control unit adjusts the output voltage to a second predetermined voltage. The power supply system as described in claim 9, further comprising: a bypass switch, connected in parallel with the boost converter, and coupled to the control unit; wherein the control unit calculates the output voltage as the first predetermined value voltage, a first loss of the boost converter and the power line, and calculate a second loss of the power line when the boost converter is bypassed; when the control unit determines that the first loss is greater than or equal to the second loss When loss occurs, the control unit turns on the bypass switch to bypass the boost converter. The power supply system as described in claim 9, further comprising: a bypass switch, connected in parallel with the boost converter, and coupled to the control unit; wherein the detection circuit is further coupled to the input end, and The control unit detects the input terminal through the detection circuit to obtain the input voltage; when the control unit learns through the detection circuit that a voltage difference between the input voltage and the output voltage is lower than a threshold, the control unit The unit turns on the bypass switch to bypass the boost converter.

Images