Power amplifier n+1 backup system and method allowing safe hot plug of power amplifier unit

Abstract

The invention discloses a power amplifier (n + 1) backup system and method allowing safe hot plug of power amplifier units. The power amplifier (n + 1) backup system comprises n 2-in-1 units, n main power amplifier units and a standby power amplifier unit, each two-in-one unit comprises a first 3dB coupler, a second 3dB coupler and a reflective phase shifter; the power synthesis proportion of the two-in-one unit is adjusted through the reflective phase shifter; when any main power amplifier unit breaks down, the power synthesis proportion of the main power amplifier unit which breaks down is adjusted to be 0 by adjusting the power synthesis proportion of the two-in-one unit connected to the main power amplifier unit, the power synthesis proportion of all the preceding two-in-one synthesis units is adjusted, the standby power amplifier unit is connected to the first two-in-one unit, and full-power output is achieved. And replacing the failed main power amplifier unit with a new power amplifier unit, inserting the new power amplifier unit into the power amplifier n + 1 backup system, and adjusting the output power of the backup power amplifier unit to be 0 by adjusting the power synthesis proportion of the accessed 2-in-1 unit and all the preceding-stage 2-in-1 synthesis units.

Description

Technical Field

[0001] The invention belongs to the field of electronic information / radio frequency / broadcasting and television passive devices, and in particular relates to a power amplifier n+1 backup system and method that allows power amplifier units to be safely hot-swapped. Background Art

[0002] High-power synthesizers are an important component of high-power radio frequency systems and have important applications in basic scientific research, nuclear physics, military, agriculture, medical and other fields. High-power synthesizers combine the output power of multiple power sources, and the power can reach kilowatts or even megawatts. In order to achieve the required power level, some power synthesis systems need to synthesize the output power of several to thousands of power amplifier units for application, which requires the development of a power synthesis system with multiple inputs.

[0003] Power combiners have various structures and types. According to the power level, power combiners can be divided into chip-level power combiners, circuit-level power combiners, spatial power combiners, and other power combiners. Among them, circuit-level power combiners are a type of power combiner with moderate power levels, which are suitable for combining and applying the output power of multiple power amplifier modules. According to whether a resonant cavity is included, circuit-level power combiners can be divided into resonant cavity power combiners and nonresonant cavity power combiners.

[0004] Compared with the power source composed of electron tubes or traveling wave tubes, the power source system composed of multiple power amplifier units has a major competitive advantage in that there are a large number of power amplifier units in the system. When a power amplifier unit fails, the entire power source system can adjust itself to ensure the normal operation of the system without directly shutting down the entire system. Therefore, this requires the entire synthesizer system to have sufficient power capacity redundancy and stability.

[0005] When the power source system is used in the semiconductor etching industry or accelerator-related fields, the load state of the power source may change dramatically during operation, and even the power source output may be fully reflected. When the output is fully reflected, the application requires the entire power source system to work normally, and neither the power amplifier unit nor the synthesizer can be damaged. In other words, the power amplifier unit and the power synthesizer of this power source must have the "anti-total reflection" function.

[0006] When a power amplifier unit of the power source fails and the entire system cannot be shut down for maintenance, it is necessary to unplug the failed power amplifier unit while the power source is powered, and then replace it with a new power amplifier unit. The new power amplifier unit must also be plugged in while the power source is powered. This is the "hot plug" function requirement for the power amplifier unit. In fact, the process of hot plugging the power amplifier unit is very complicated. When the metal parts of the power amplifier unit and the power synthesizer are in a state of quasi-contact or non-contact, sparking and discharge are very likely to occur, which may cause equipment damage or even personal injury to the operator in severe cases. Therefore, when the power source is powered, there is a greater risk of directly hot plugging the power amplifier unit. In particular, when the power source system has output total reflection, when a power amplifier unit is hot plugged at this time, the risk of equipment damage or even personal injury will be greater.

[0007] In order to achieve safe hot-swapping of power amplifier units, one method is to "decouple" the input port corresponding to the power synthesizer before plugging in or out the power amplifier unit. After decoupling, the coupling coefficient between the synthesizer input port and the outside is close to 0, and the plug-in power amplifier no longer outputs or bears power. At this time, unplugging or plugging in the power amplifier unit will indeed effectively improve the safety of the hot-swapping process. However, the decoupling structure of this synthesizer port is often more complicated, requiring a motor to drive the port component to move or rotate, which will significantly increase the complexity and cost of the entire system. Moreover, when the faulty power amplifier is unplugged, in order to ensure that the output power of the entire power source remains basically unchanged, the output power of other power amplifier units needs to be pushed up. The output power of each power amplifier unit may reach 130% of its rated output power or even higher, which also puts higher requirements on the design of the power amplifier unit. Summary of the invention

[0008] Purpose of the invention: To achieve safe hot-swapping of power amplifier units, the present invention proposes a power amplifier n+1 backup system and method that allows safe hot-swapping of power amplifier units.

[0009] Technical solution: An n+1 backup system for power amplifiers that allows safe hot swapping of power amplifier units, comprising: n 2-in-1 units, n main power amplifier units and 1 backup power amplifier unit;

[0010] Each 2-in-1 unit includes a first 3dB coupler, a second 3dB coupler and a reflective phase shifter;

[0011] An input port of the first 3dB coupler serves as the first input port of the 2-in-1 unit, and another input port of the first 3dB coupler serves as the second input port of the 2-in-1 unit; an output port of the first 3dB coupler is connected to an input port of the second 3dB coupler, and another output port of the first 3dB coupler is connected to an input port of the reflective phase shifter; another input port of the second 3dB coupler is connected to another input port of the reflective phase shifter; an output port of the second 3dB coupler serves as the output port of the 2-in-1 unit, and another output port of the second 3dB coupler serves as the load port of the 2-in-1 unit, and a load unit is connected to the load port;

[0012] The power synthesis ratio of the 2-in-1 unit is adjusted by a reflective phase shifter;

[0013] For the first 2-in-1 unit, its first input port is connected to the backup power amplifier unit, and its second input port is connected to a main power amplifier unit. For other 2-in-1 units, their first input port is connected to the output port of the previous 2-in-1 unit. For the last 2-in-1 unit, its output port is the total output port of the entire power amplifier n+1 backup system.

[0014] Further, the reflective phase shifter includes a third 3dB coupler, a first adjustable short-circuit branch and a second adjustable short-circuit branch;

[0015] An input port of the third 3dB coupler is connected to another output port of the first 3dB coupler, another input port of the third 3dB coupler is connected to another output port of the second 3dB coupler, an output port of the third 3dB coupler is connected to the first adjustable short-circuit branch, and another output port of the third 3dB coupler is connected to the second adjustable short-circuit branch;

[0016] The positions of the short-circuit surfaces of the first adjustable short-circuit branch and the second adjustable short-circuit branch are adjusted by an external driving mechanism to change the phase difference between the two ports of the third 3dB coupler, thereby adjusting the power synthesis ratio of the 2-in-1 unit.

[0017] Furthermore, the changing of the phase difference between the two ports of the third 3dB coupler, thereby adjusting the power synthesis ratio of the 2-in-1 unit, specifically includes:

[0018] When the phase difference = 0, the power synthesis ratio of the two input ports of the 2-in-1 unit is 0%:100%;

[0019] When the phase difference = -36.8, the power synthesis ratio of the two input ports of the 2-in-1 unit is 10%:90%;

[0020] When the phase difference = -53.1, the power synthesis ratio of the two input ports of the 2-in-1 unit is 20%:80%;

[0021] When the phase difference = -66.4, the power synthesis ratio of the two input ports of the 2-in-1 unit is 30%:70%;

[0022] When the phase difference = -78.5, the power synthesis ratio of the two input ports of the 2-in-1 unit is 40%:60%;

[0023] When the phase difference = -90, the power synthesis ratio of the two input ports of the 2-in-1 unit is 50%:50%;

[0024] When the phase difference = -101.5, the power synthesis ratio of the two input ports of the 2-in-1 unit is 60%:40%;

[0025] When the phase difference = -113.6, the power synthesis ratio of the two input ports of the 2-in-1 unit is 70%:30%;

[0026] When the phase difference = -126.8, the power synthesis ratio of the two input ports of the 2-in-1 unit is 80%:20%;

[0027] When the phase difference = -143.1, the power synthesis ratio of the two input ports of the 2-in-1 unit is 90%:10%;

[0028] When the phase difference = -180, the power synthesis ratio of the two input ports of the 2-in-1 unit is 100%:0%;

[0029] Where, phase difference = (Φ (2-2) -Φ (1-3) )-(Φ (2-1) -Φ (1-4) ), where Φ (2-2) represents the phase of the other output port of the second 3dB coupler, Φ (1-3) represents the phase of the other output port of the first 3dB coupler, Φ (2-1) represents the phase of an output port of the second 3dB coupler, Φ (1-4) represents the phase of an output port of the first 3dB coupler.

[0030] Furthermore, two adjacent 2-in-1 units are connected via a hard feeder.

[0031] The present invention also discloses a method for safely plugging and unplugging a power amplifier unit, comprising the following steps:

[0032] Step 1: constructing a power amplifier n+1 backup system; the power amplifier n+1 backup system is a power amplifier n+1 backup system that allows safe hot swapping of power amplifier units;

[0033] Step 2: When any main power amplifier unit fails, adjust the power synthesis ratio of the 2-in-1 unit connected to it to adjust the power synthesis ratio of the main power amplifier unit with the failure to 0, and adjust the power synthesis ratio of all the previous 2-in-1 synthesis units, connect the backup power amplifier unit to the first 2-in-1 unit, output at full power, and then unplug the main power amplifier unit with the failure;

[0034] Step 3: Replace the faulty main power amplifier unit with a new one and insert it back into the power amplifier n+1 backup system. Adjust the power synthesis ratio of the connected 2-in-1 unit and the power synthesis ratio of all the preceding 2-in-1 synthesis units to adjust the output power of the backup power amplifier unit to 0.

[0035] Beneficial effect: Compared with the prior art, the present invention designs a backup power amplifier unit in addition to n main power amplifier units. When any main power amplifier unit fails, the backup power amplifier unit is connected to the power source system by adjusting the power ratio of each power synthesis unit, and the power ratio of the faulty main power amplifier unit is adjusted to 0. At this time, the output power of the backup power amplifier unit replaces the faulty main power amplifier unit, ensuring the normal operation of the entire power source system and the total output power can remain unchanged; at this time, the faulty power amplifier unit can be safely unplugged without any safety issues. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a schematic diagram of the 8+1 power amplifier backup system proposed in Example 1;

[0037] Figure 2 A three-dimensional diagram of the 8+1 power amplifier backup system proposed in Example 1;

[0038] Figure 3 for Figure 2 A front view of

[0039] Figure 4 for Figure 2 A top view of

[0040] Figure 5 It is a schematic diagram of the structure of a single 2-in-1 synthesis unit;

[0041] Figure 6 This is a schematic diagram of the backup switching principle of the 8+1 power amplifier backup system;

[0042] Figure 7 Schematic diagram for a single 2-in-1 unit. DETAILED DESCRIPTION

[0043] The technical solution of the present invention is now further described in conjunction with the accompanying drawings and embodiments.

[0044] This embodiment proposes an 8+1 power amplifier backup system that allows safe hot swapping of power amplifier units, including: 8 2-in-1 units with arbitrarily adjustable power ratios, 8 main power amplifier units and a backup power amplifier unit (in Figure 1 The eight 2-in-1 units are cascaded, such as Figure 1 As shown, unit 1 to unit 8 are 8 2-in-1 units, and the power synthesis ratio of each 2-in-1 unit is adjusted by electronic control.

[0045] When any 2-in-1 unit fails, the spare power amplifier unit P_spare is connected to the power source system by adjusting the power synthesis ratio, and the power ratio of the faulty power amplifier unit is adjusted to 0. At this time, the output power of the spare power amplifier unit P_spare replaces the faulty power amplifier unit, ensuring the normal operation of the entire power source system and the total output power can remain unchanged. At this time, the faulty power amplifier unit can be safely unplugged without any safety issues.

[0046] Figure 6 The backup switching principle of the entire power amplifier 8+1 backup system is shown. Under normal working conditions, the 8 2-in-1 units are adjusted to "0+1", "1+1" ... "7+1" modes respectively, the 8 main power amplifier units output power normally, and the backup power amplifier unit outputs 0 power. When any main power amplifier unit fails and becomes 0 power output, all the front-stage 2-in-1 synthesis units corresponding to this power amplifier must adjust the working mode, and the backup power amplifier unit outputs at full power to ensure that the output power of the entire system remains unchanged. For example, when P4 is damaged, the 2-in-1 synthesis unit of the front stage of this power amplifier unit needs to be adjusted to "1+1", "2+1", "3+1", "4+0" modes respectively. In particular, the working mode of the 4th 2-in-1 synthesis unit needs to be adjusted to "4+0", that is, the front-stage input power of the synthesis unit is 4P, plus the 0 power of the 4th main power amplifier unit (fault), the output power of the synthesis unit is still 4P. The rear-stage synthesizer does not need to be adjusted. When the faulty amplifier unit has zero power output and the entire combiner has been adjusted, the amplifier unit can be safely unplugged. After inspection, or directly replace a new amplifier unit, plug it back into the power combiner. After that, reverse the above steps to switch the system back to normal working state.

[0047] Figure 5 shows the structure of the 2-in-1 unit constituting the above backup system, Figure 7The principle of the 2-in-1 unit constituting the backup system is shown. Each 2-in-1 unit includes: 2 3dB couplers for coupling strip lines, 1 reflective phase shifter and connection accessories required for system connection. The reflective phase shifter includes: 1 3dB coupler, 2 adjustable short-circuit branches, a motor and a drive system for driving the adjustable short-circuit branches. By changing the position of the short-circuit surfaces of the two adjustable short-circuit branches, the phase between the two ports of the reflective phase shifter can be changed to achieve the purpose of phase shifting.

[0048] By adjusting the positions of the short-circuit surfaces of the two adjustable short-circuit branches and changing the phase difference between the two ports of the reflective phase shifter, the power ratio of the two input ports of the 2-in-1 synthesis unit can be changed, as shown in the following table.

[0049]

[0050] In the table, ΔΦ represents the phase difference between the two ports of the reflective phase shifter, ΔΦ=(Φ (2-2) -Φ (1-3) )-(Φ (2-1) -Φx 1-4) ), where Φ (2-2) represents the phase of port 2-2 of the second 3dB coupler, Φ (1-3) represents the phase of port 1-3 of the first 3dB coupler, Φ (2-1) represents the phase of port 2-1 of the second 3dB coupler, Φ (1-4) represents the phase of ports 1-4 of the first 3dB coupler.

[0051] In this embodiment, the 2-in-1 unit constituting the above backup system can be realized by adjusting the phase of the reflective phase shifter in the unit. For example, when the power of the two input ports is 50%, it is the "1+1" mode; when the power of the two input ports is 25% and 75% respectively, it is the "1+3" mode; when the power of the two input ports is 100% and 0 respectively, it is the "n+0" mode, and so on.

[0052] Figure 5The hardware structure of the 2-in-1 unit is shown, including: a first 3dB coupler 1, a second 3dB coupler 2, a third 3dB coupler 3, a first input port 4, a second input port 5, an output port 6, a load port 7, a load unit 8, a first adjustable short-circuit branch 9, a second adjustable short-circuit branch 10 and a drive system 11. Port 1-1 of the first 3dB coupler 1 is connected to the first input port 4, port 1-2 of the first 3dB coupler 1 is connected to the second input port 5, port 1-4 of the first 3dB coupler 1 is connected to port 2-1 of the second 3dB coupler 2 through a hard feeder, port 1-3 of the first 3dB coupler 1 is connected to port 3-2 of the third 3dB coupler 3; port 2-2 of the second 3dB coupler 2 is connected to port 3-1 of the third 3dB coupler 3, port 2-4 of the second 3dB coupler 2 is connected to the output port 6, port 2-3 of the second 3dB coupler 2 is connected to the load port 7, and a load unit 8 is connected to the load port 7; port 3-3 of the third 3dB coupler 3 is connected to the first adjustable short-circuit branch node 9, and port 3-4 of the third 3dB coupler 3 is connected to the second adjustable short-circuit branch node 10. The driving system 11 changes the positions of the short-circuit surfaces of the two adjustable short-circuit branches to change the phase between the two ports of the third 3dB coupler 3, thereby achieving the purpose of phase shifting.

[0053] like Figure 2 , Figure 3 and Figure 4 As shown, the hardware structure of an 8+1 power amplifier backup system that allows safe hot swapping of power amplifier units proposed in this embodiment includes: 8 2-in-1 units, 8 main power amplifier units and 1 backup power amplifier unit; Figure 4 The schematic diagram of the cascade connection of 8 2-in-1 units is shown. For the first 2-in-1 unit, its first input port 4 is connected to the backup power amplifier unit, and its second input port 5 is connected to the main power amplifier unit. The output port of each 2-in-1 unit is connected to the first input port of the next 2-in-1 unit through a hard feeder. The output port of the 8th 2-in-1 unit is the final total output port P.

[0054] The n+1 power amplifier backup system proposed in this embodiment can meet the following technical index requirements:

[0055] Working frequency: 470~700MHz;

[0056] Number of power amplifier units: 8+1;

[0057] Rated power: 8×2kW average power;

[0058] Input and output port standing wave ratio: ≤1.10;

[0059] Insertion loss: ≤0.30dB (excluding theoretical distribution loss);

[0060] Isolation: ≥25dB;

[0061] Amplitude balance: ±0.5dB;

[0062] Phase balance: in phase, ±5°;

[0063] Input and output port specifications: EIA3 1 / 8” flange port;

[0064] Cooling method: natural cooling.

Claims

1. A power amplifier n+1 backup system that allows safe hot swapping of power amplifier units, characterized in that: include: n 2-in-1 units, n main amplifier units and 1 spare amplifier unit; Each 2-in-1 unit includes a first 3dB coupler, a second 3dB coupler and a reflective phase shifter; An input port of the first 3dB coupler serves as the first input port of the 2-in-1 unit, and another input port of the first 3dB coupler serves as the second input port of the 2-in-1 unit; an output port of the first 3dB coupler is connected to an input port of the second 3dB coupler, and another output port of the first 3dB coupler is connected to an input port of the reflective phase shifter; another input port of the second 3dB coupler is connected to another input port of the reflective phase shifter; an output port of the second 3dB coupler serves as the output port of the 2-in-1 unit, and another output port of the second 3dB coupler serves as the load port of the 2-in-1 unit, and a load unit is connected to the load port; The power synthesis ratio of the 2-in-1 unit is adjusted by a reflective phase shifter; For the first 2-in-1 unit, its first input port is connected to the backup power amplifier unit, and its second input port is connected to a main power amplifier unit. For other 2-in-1 units, their first input port is connected to the output port of the previous 2-in-1 unit. For the last 2-in-1 unit, its output port is the total output port of the entire power amplifier n+1 backup system.

2. The power amplifier n+1 backup system that allows safe hot swapping of power amplifier units according to claim 1, characterized in that: The reflective phase shifter comprises a third 3dB coupler, a first adjustable short-circuit branch and a second adjustable short-circuit branch; An input port of the third 3dB coupler is connected to another output port of the first 3dB coupler, another input port of the third 3dB coupler is connected to another output port of the second 3dB coupler, an output port of the third 3dB coupler is connected to the first adjustable short-circuit branch, and another output port of the third 3dB coupler is connected to the second adjustable short-circuit branch; The positions of the short-circuit surfaces of the first adjustable short-circuit branch and the second adjustable short-circuit branch are adjusted by an external driving mechanism to change the phase difference between the two ports of the third 3dB coupler, thereby adjusting the power synthesis ratio of the 2-in-1 unit.

3. The power amplifier n+1 backup system that allows safe hot swapping of power amplifier units according to claim 2, characterized in that: The changing of the phase difference between the two ports of the third 3dB coupler, thereby adjusting the power synthesis ratio of the 2-in-1 unit, specifically includes: When the phase difference = 0, the power synthesis ratio of the two input ports of the 2-in-1 unit is 0%:100%; When the phase difference = -36.8, the power synthesis ratio of the two input ports of the 2-in-1 unit is 10%:90%; When the phase difference = -53.1, the power synthesis ratio of the two input ports of the 2-in-1 unit is 20%:80%; When the phase difference = -66.4, the power synthesis ratio of the two input ports of the 2-in-1 unit is 30%:70%; When the phase difference = -78.5, the power synthesis ratio of the two input ports of the 2-in-1 unit is 40%:60%; When the phase difference = -90, the power synthesis ratio of the two input ports of the 2-in-1 unit is 50%:50%; When the phase difference = -101.5, the power synthesis ratio of the two input ports of the 2-in-1 unit is 60%:40%; When the phase difference = -113.6, the power synthesis ratio of the two input ports of the 2-in-1 unit is 70%:30%; When the phase difference = -126.8, the power synthesis ratio of the two input ports of the 2-in-1 unit is 80%:20%; When the phase difference = -143.1, the power synthesis ratio of the two input ports of the 2-in-1 unit is 90%:10%; When the phase difference = -180, the power synthesis ratio of the two input ports of the 2-in-1 unit is 100%:0%; Where, phase difference = (Φ (2-2) -Φ (1-3) )-(Φ (2-1) -Φ (1-4) ), where Φ (2-2) represents the phase of the other output port of the second 3dB coupler, Φ (1-3) represents the phase of the other output port of the first 3dB coupler, Φ (2-1) represents the phase of an output port of the second 3dB coupler, Φ (1-4) represents the phase of an output port of the first 3dB coupler.

4. The power amplifier n+1 backup system that allows safe hot swapping of power amplifier units according to claim 2, characterized in that: Two adjacent 2-in-1 units are connected via a hard feeder.

5. A method for safely plugging and unplugging a power amplifier unit, characterized in that: The following steps are involved: Step 1: constructing a power amplifier n+1 backup system; the power amplifier n+1 backup system is a power amplifier n+1 backup system that allows safe hot swapping of power amplifier units as described in any one of claims 1 to 4; Step 2: When any main power amplifier unit fails, adjust the power synthesis ratio of the 2-in-1 unit connected to it to adjust the power synthesis ratio of the main power amplifier unit with the failure to 0, and adjust the power synthesis ratio of all the previous 2-in-1 synthesis units, connect the backup power amplifier unit to the first 2-in-1 unit, output at full power, and then unplug the main power amplifier unit with the failure; Step 3: Replace the faulty main power amplifier unit with a new one and insert it back into the power amplifier n+1 backup system. Adjust the power synthesis ratio of the connected 2-in-1 unit and the power synthesis ratio of all the preceding 2-in-1 synthesis units to adjust the output power of the backup power amplifier unit to 0.

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