A power amplifier

Abstract

The present invention discloses a power amplifier, comprising a controller, a driving module, a power amplifier module, and a filtering module. The controller is electrically connected to the power amplifier module via the driving module and transmits a PWM modulated signal. The output end of the power amplifier module is electrically connected to the filtering module. The power amplifier module includes n power amplifier units, each of which includes an input end and an output end. The input ends of the n power amplifier units are connected in series, and the output ends of the n power amplifier units are connected in parallel. The input end of the power amplifier module is connected to an external high-voltage DC power supply unit. The n power amplifier units of the power amplifier module of the present invention are connected in series with their inputs connected and in parallel with their outputs. Multiple amplified signal powers are synthesized. The level of the operating input voltage and the magnitude of the output signal power of the power amplifier can be adjusted by adjusting the number of power amplifier units to adapt to applications with different power outputs and different voltage inputs.

Description

Technical Field

[0001] The present invention relates to the technical field of power electronics, and in particular to a power amplifier. Background Art

[0002] Since the beginning of the 21st century, power electronics technology has experienced rapid development, and power amplifiers have been widely used in many areas of social life. Traditional analog and Class AB amplifiers suffer from drawbacks such as low efficiency, bulk, and weight. Digital power amplifiers, on the other hand, not only offer a simple structure, high transmission efficiency, and ease of integration, but also offer significant advantages in size, weight, efficiency, and reliability, leading to their rapid development in recent years.

[0003] However, due to the limitations of the process level and technology of power switching devices, the power level, voltage level and switching frequency of single-module digital power amplifiers are limited, making it difficult to meet the needs of some high-voltage input, high-power, and low-distortion applications.

[0004] To address this issue, currently known high-power digital amplifiers suitable for high-voltage DC input typically employ a two-stage power conversion process: DC / DC high-voltage power conversion and digital power amplification. This achieves the high-voltage input and high-power output requirements. The power amplifier typically utilizes higher-power transistors connected in series or parallel, or cascaded power modules, to achieve the high-power requirements.

[0005] However, due to the non-ideal switching characteristics of the devices, the series-parallel combination increases the equivalent input capacitance, further reducing the actual switching frequency, worsening the digital amplifier's distortion, and increasing the size of the filter module. Furthermore, since the characteristics of each device / module may not be exactly the same, the voltage and current experienced by each device / module are uneven, potentially causing damage and degrading system reliability. Furthermore, the use of two-stage power conversion significantly reduces amplifier efficiency and increases control logic complexity.

[0006] Therefore, it is of great significance to provide a high-power digital power amplifier with high reliability, modularity, low distortion and suitable for high voltage DC input. Summary of the Invention

[0007] In order to solve the above technical problems, the present invention provides a power amplifier.

[0008] According to one aspect of the present application, a power amplifier is provided, including a controller, a driving module, a power amplification module and a filtering module, the controller being electrically connected to the power amplification module through the driving module and transmitting a PWM modulation signal, and the output end of the power amplification module being electrically connected to the filtering module; wherein the power amplification module includes n power amplification units, each power amplification unit respectively including an input end and an output end, the input ends of the n power amplification units being connected in series, the output ends of the n power amplification units being connected in parallel, the input end of the power amplification module being connected to an external high-voltage DC power supply unit, 1≤n≤32.

[0009] Optionally, the controller is used to complete signal sampling / caching, and perform PWM pulse width modulation with 2n digital triangular carriers with the same frequency and a phase difference of π / n, to generate 2n groups of PWM modulation signals with the same frequency and a phase difference of π / n, and each group of PWM modulation signals includes two PWM modulation signals with complementary levels, and its duty cycle is proportional to the amplitude of the input signal.

[0010] Optionally, the driving circuit module is located between the controller and the power amplifier module, and is used to receive 2n groups of PWM modulation signals output by the controller and perform power amplification of the PWM modulation signals so as to drive the power amplifier module.

[0011] Optionally, each power amplification unit includes a full-bridge inverter circuit, and each full-bridge inverter circuit includes an H-bridge circuit, an input capacitor and a transformer; the H-bridge circuit is formed by four groups of power switching units with the same circuit structure connected in an H-bridge form, wherein each group of power switching units includes a power switching device.

[0012] Optionally, the input terminals of the H-bridge circuit and the input capacitor are connected in parallel between the positive electrode of the power amplifier module input terminal and the negative electrode of the power amplifier module input terminal, and the H-bridge circuit receives high-voltage DC power from the high-voltage DC power supply unit; the two power switching devices in the same bridge arm of the H-bridge circuit receive a set of PWM modulation signals output by the drive circuit module, so as to realize power amplification of the output signal of the drive module.

[0013] Optionally, the transformer includes a primary winding and a secondary winding, and the two output ends of the H-bridge circuit are respectively connected to the two ends of the primary winding of the transformer; the two ends of the secondary winding of the transformer are respectively connected to the positive pole of the output end of the power amplifier module and the negative pole of the output end of the power amplifier module.

[0014] Optionally, the controller includes a sampling / buffering module, a timer, 2n PWM modulators, and a fault processing module running in parallel under the same clock beat;

[0015] The sampling / buffering module is used to receive the input signal, digitize and buffer the input signal, and then transmit it to 2n PWM modulators;

[0016] The timer is used to receive the start / stop signal and send 2n phase trigger signals with a time interval of T / 2n to 2n PWM modulators, where T is the carrier period of the PWM modulator.

[0017] The 2n PWM modulators are used to complete PWM modulation of the signal output by the sampling / buffering module; and are also used to control the carrier phase of the output PWM modulated signal according to the phase trigger signal after receiving the phase trigger signal;

[0018] The fault processing module is used to obtain fault information of the power amplifier unit in the power amplifier module, send a fault bypass control signal to the faulty power amplifier unit, and send an output phase shift control signal and an enable control signal to the timer and PWM modulator corresponding to the faulty power amplifier unit respectively.

[0019] Optionally, the power amplifier also includes a status acquisition module, which is electrically connected to the controller, the driving module and the power amplification module respectively. The status acquisition module is used to collect the working status of the driving module and the power amplification module, and output fault information to the fault processing module of the controller according to the working status. The fault information includes the number and fault location of the power amplification unit in the power amplification module.

[0020] Optionally, each PWM modulator includes a counter and a comparator arranged in a one-to-one correspondence, wherein the counter is started by the corresponding phase trigger signal output by the timer to generate a periodic digital triangular modulated carrier; the comparator is used to compare the count value of the counter with the digital quantization value of the input signal in real time and output a PWM modulated signal.

[0021] Optionally, the input signal is pulse-width modulated to generate 2n groups of PWM modulation signals, including:

[0022] The input signal is pulse-width modulated with 2n digital triangle modulation carriers with the same frequency and a phase difference of π / n to generate 2n groups of PWM modulation signals.

[0023] The power amplifier provided in the present application includes a power amplifier module, wherein n power amplifier units of the power amplifier module are connected in a series input and parallel output manner, and the n power amplifier units respectively power amplify and process multiple groups of PWM modulated signals, and the power of multiple amplified signals is synthesized. The level of the working input voltage and the size of the output signal power of the power amplifier of the present application can be adjusted by adjusting the number of power amplifier units to adapt to applications with different power outputs and different voltage inputs.

[0024] The n power amplification units of the power amplification module of the power amplifier of the present application are independently arranged, have a high degree of modularization, and are easy to expand and maintain.

[0025] The single-stage power conversion structure of the power amplifier of the present application can meet the requirements of high-voltage input and high-power output, improve the working efficiency and integration of the power amplifier, simplify the equipment control process, and the signal enters the power amplifier module for single-stage amplification and then power synthesis. The signal output after power synthesis has low distortion. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings, which constitute part of the present invention, are provided to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are provided to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0027] Figure 1 is a block diagram of a power amplifier in an example;

[0028] Figure 2 This is a circuit diagram of a full-bridge inverter circuit in an example;

[0029] Figure 3 is a schematic diagram of a controller in an example;

[0030] Figure 4 This is a block diagram of a full-bridge inverter circuit in an example. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. It should be noted that, in the absence of conflict, the embodiments in this application and the feature vectors in the embodiments can be arbitrarily combined with each other.

[0032] Due to the limitations of the process level and technology of power switching devices, the power level, voltage level and switching frequency of single-module digital power amplifiers are limited, making it difficult to meet the needs of some high-voltage input, high-power, and low-distortion applications.

[0033] To address this issue, currently known high-power digital amplifiers suitable for high-voltage DC input typically employ a two-stage power conversion process: DC / DC high-voltage power conversion and digital power amplification. This achieves the high-voltage input and high-power output requirements. The power amplifier typically utilizes higher-power transistors connected in series or parallel, or cascaded power modules, to achieve the high-power requirements.

[0034] However, due to the non-ideal switching characteristics of the devices, the series-parallel combination increases the equivalent input capacitance, further reducing the actual switching frequency, worsening the digital amplifier's distortion, and increasing the size of the filter module. Furthermore, since the characteristics of each device / module may not be exactly the same, the voltage and current experienced by each device / module are uneven, potentially causing damage and degrading system reliability. Furthermore, the use of two-stage power conversion significantly reduces amplifier efficiency and increases control logic complexity.

[0035] Therefore, it is of great significance to provide a high-power digital power amplifier with high reliability, modularity, low distortion and suitable for high voltage DC input.

[0036] To this end, the present application provides a power amplifier, including a controller, a driving module, a power amplification module and a filtering module. The power amplification module includes n power amplification units, the input ends of the n power amplification units are connected in series, and the output ends of the n power amplification units are connected in parallel. The n power amplification units respectively power amplify and process the PWM modulated signals and then output them in parallel to achieve power synthesis. The level of the working input voltage and the size of the output signal power adapted by the power amplifier of the present application can be adjusted by adjusting the number of power amplification units.

[0037] In the embodiment of the present application, the power amplifier of the present application, such as Figure 1 As shown, it includes a controller, a driving module, a power amplification module and a filtering module. The controller is electrically connected to the power amplification module through the driving module and transmits a PWM modulation signal. The output end of the power amplification module is electrically connected to the filtering module. The power amplification module includes n power amplification units, each power amplification unit includes an input end and an output end. The input ends of the n power amplification units are connected in series, and the output ends of the n power amplification units are connected in parallel. The input end of the power amplification module is connected to the high-voltage DC power supply unit, and 1≤n≤32.

[0038] Among them, the working input voltage of the high-voltage DC power supply unit is 500V~16kV.

[0039] In the power amplifier of the present application, the PWM modulated signal received by the power amplifier module enters n power amplifier units for power amplification respectively, and the power-amplified signal is output through the output end of the power amplifier unit to achieve power synthesis, and the power amplifier module outputs the power-synthesized signal. The power amplifier of the present application is a single-stage power conversion structure. The present application connects n power amplifier units in series input and parallel output, so that the power amplifier of the present application can meet the use requirements of high-voltage DC input and high-power output. Moreover, in the present application, the PWM modulated signal enters the power amplifier module for single-stage amplification and then power synthesis, and the distortion of the power synthesized signal is significantly better than that of the power signal of multi-stage amplification.

[0040] In an embodiment of the present application, the controller is used to complete signal sampling / caching, and perform PWM pulse width modulation with 2n digital triangular carriers with the same frequency and a phase difference of π / n, to generate 2n groups of PWM modulation signals with the same frequency and a phase difference of π / n, and each group of PWM modulation signals includes two PWM modulation signals with complementary levels, and its duty cycle is proportional to the amplitude of the input signal.

[0041] In an embodiment of the present application, the driving circuit module is located between the controller and the power amplifier module, and is used to receive 2n groups of PWM modulation signals output by the controller and complete power amplification of the PWM modulation signals so that they can drive the power amplifier module.

[0042] As an embodiment of the present application, most of the contents of this embodiment are the same as those of the above embodiments, except that Figure 2 As shown, each power amplifier unit includes a full-bridge inverter circuit, which includes an H-bridge circuit, input capacitor C, and transformer T. The H-bridge circuit is formed by four groups of power switching units Q with identical circuit structures connected in an H-bridge configuration. Each group of power switching units Q includes a power switching device. Two power switching units Q in the same arm of the H-bridge circuit receive a set of PWM modulation signals output by the driver module.

[0043] In this embodiment, each power amplifier unit receives two sets of PWM modulation signals, and the two bridge arms of the H-bridge circuit each receive one set of PWM modulation signals and perform power amplification processing on the one set of PWM modulation signals. The two bridge arms of the H-bridge circuit each process the two sets of PWM modulation signals, thereby improving the operating efficiency of the power amplifier unit, increasing the integration of the power amplifier module, and simplifying the power amplification process of the power amplifier of the present application.

[0044] like Figure 2As shown, the input terminals of the H-bridge circuit and the input capacitor C are connected in parallel between the positive and negative terminals of the power amplifier module input. The two bridge arms of the H-bridge circuit receive high-voltage DC power from the high-voltage DC power supply unit. The two power switch units Q in the same bridge arm are each connected to the driver module. The transformer T includes a primary winding and a secondary winding. The H-bridge circuit is connected to the two terminals of the primary winding of the transformer T, and the two terminals of the secondary winding of the transformer T are connected to the positive and negative terminals of the output terminal of the power amplifier module, respectively.

[0045] As an embodiment of the present application, Figure 2 As shown, each leg of the H-bridge circuit includes a first power switch unit Q1 and a second power switch unit Q2 connected in series. The gate of the first power switch unit Q1 is connected to a driver module, and the emitter of the first power switch unit Q1 is connected to the collector of the second power switch unit Q1 and the positive or negative electrode of the primary winding of the transformer, respectively. The collector of the first power switch unit Q1 is connected to the positive electrode of the input terminal. The gate of the second power switch unit Q2 is connected to the driver module, and the emitter of the second power switch unit Q2 is connected to the negative electrode of the input terminal.

[0046] In this embodiment, the emitter of the first power switch unit Q1 in one of the two bridge arms of the H-bridge circuit is connected to the positive electrode of the primary winding of the transformer, while the emitter of the first power switch unit Q1 in the other bridge arm is connected to the negative electrode of the primary winding of the transformer. One bridge arm of the H-bridge circuit receives a set of PWM modulation signals from a driver module and transmits them to the positive electrode of the primary winding of the transformer T, while the other bridge arm receives another set of PWM modulation signals from the driver module and transmits them to the negative electrode of the primary winding of the transformer T. The primary winding is excited by the high-voltage DC current at the input terminal, and the secondary winding and the primary winding are inductively coupled, generating an excitation response that amplifies the PWM modulation signal received by the primary winding and outputs it to the output terminal.

[0047] The power switching device on each power switching unit Q is an insulated gate bipolar transistor IGBT, a semiconductor field effect transistor MOSFET or a silicon carbide MOSFET tube.

[0048] In this embodiment, if Figure 2 As shown, each full-bridge inverter circuit further includes a bypass switch K, which is arranged between the positive electrode of the input terminal and the negative electrode of the input terminal, and the bypass switch K is connected in parallel with the input capacitor C.

[0049] When the power amplifier unit is in operation, the bypass switch K is in the open state. When the bypass switch K is closed, the input capacitor C is short-circuited, and the power amplifier unit stops operating. The power amplifier of the present application can adjust the number of power amplifier units performing power amplification by adjusting the open or closed state of the bypass switches K of n power amplifier units, thereby adjusting the adaptive operating input voltage level and output signal power of the power amplifier of the present application.

[0050] Moreover, when one or n power amplification units of the power amplifier of the present application fail, the bypass switch K of the failed power amplification unit can be closed, and the power amplifier can continue to work.

[0051] As an embodiment of the present application, Figure 3 As shown, the power amplifier controller of the present application includes a sampling / buffer module, a timer, and 2n PWM modulators running in parallel under the same clock beat.

[0052] The sampling / buffering module is used to receive input signals, digitally quantize and buffer the input signals, and then transmit them to 2n PWM modulators.

[0053] The timer is used to receive the start / stop signal and send 2n phase trigger signals TRG with a time interval difference of T / (2n) to 2n PWM modulators, where T is the carrier period of the PWM modulator.

[0054] The 2n PWM modulators are used to complete PWM modulation of the signal output by the sampling / buffering module; and are also used to control the carrier phase of the output PWM modulated signal according to the phase trigger signal TRG after receiving the phase trigger signal TRG.

[0055] Each PWM modulator includes a counter and a comparator set in a one-to-one correspondence. The counter is activated by the corresponding phase trigger signal TRG output by the timer to generate a periodic digital triangular modulated carrier; the comparator is used to compare the counter count value with the digital quantization value of the input signal in real time and transmit the PWM modulated signal to the drive module.

[0056] In this embodiment, the comparator includes a PWM / output terminal and a / PWM output terminal. The comparator compares the digital size of the triangular carrier and the signal. The PWM / output terminal outputs a PWM / modulation signal, and the / PWM output terminal outputs a / PWM modulation signal. The PWM / modulation signal and the / PWM modulation signal constitute a set of PWM modulation signals output by the comparator to the driving module.

[0057] Among them, when the value of the signal is greater than the value of the triangular carrier, the PWM / output end outputs a high-level modulation signal, and the / PWM output end outputs a low-level modulation signal. When the value of the signal is less than the value of the triangular carrier, the PWM / output end outputs a low-level modulation signal, and the / PWM output end outputs a high-level modulation signal.

[0058] Based on this implementation, in a group of modulation signals output by the comparator, the levels of the / PWM modulation signal and the PWM / modulation signal are complementary, and the duty cycle is linearly correlated with the amplitude of the signal.

[0059] As an embodiment of the present application, Figure 3 As shown, the controller includes a fault processing module, which is electrically connected to the timer, 2n PWM modulators and the power amplifier module respectively, and outputs a fault modulation signal.

[0060] As a preferred embodiment of the present application, the fault information includes the fault number and fault location of the faulty power amplifier unit in the power amplifier module, m≤n. The fault control signal sent by the fault processing module includes a phase shift control signal, an enable control signal EN, and a fault bypass control signal.

[0061] like Figure 3 、 4 As shown, the fault processing module sends a phase-shift control signal to the timer. The phase-shift control signal includes the number of faulty power amplifier units. The timer adjusts the number of phase trigger signals generated based on the number of faulty power amplifier units. The fault processing module sends an enable control signal Em to the PWM modulator corresponding to the faulty power amplifier unit, shielding the PWM modulated signal output by the PWM modulator corresponding to the faulty power amplifier unit. The fault processing module also sends a bypass control signal to the faulty power amplifier unit, causing the faulty power amplifier unit to stop operating.

[0062] As an embodiment of the present application, the fault processing module is respectively connected to the bypass switches K of the n power amplification units of the power amplification module. The fault processing module receives the fault information and sends a bypass control signal to the bypass switch K of the faulty power amplification unit. The bypass switch K that receives the bypass control signal is closed, and the faulty power amplification unit stops working.

[0063] As an embodiment of the present application, most of the contents of this embodiment are the same as the above embodiments, except that the power amplifier of the present application also includes a state acquisition module, which is electrically connected to the controller, the driver module, and the power amplifier module, respectively, for transmitting fault information to the fault processing module. The state acquisition module is electrically connected to the driver module and the power amplifier module, and is used to collect the operating status of the driver module and the power amplifier module and obtain fault information of the driver module and the power amplifier module in real time. The state acquisition module is electrically connected to the controller and is used to transmit the collected fault information to the controller so that the controller can process the fault based on the fault information.

[0064] The filtering module of the present application includes a passive low-pass ladder filter. The filtering module is used to receive the power-synthesized signal output by the power amplification module and filter the power-synthesized signal to generate a high-power analog power signal.

[0065] As an embodiment of the present application, the power amplifier of the present application includes a controller, a driving module, a power amplification module, a filtering module, and a state acquisition module, wherein the state acquisition module is electrically connected to the controller, the driving module, and the power amplification module, respectively. The controller is electrically connected to the power amplification module through the driving module and transmits a modulation signal; the filtering module is electrically connected to the power amplification module. The power amplification module includes n power amplification units, each of which includes an input terminal DC_in and an output terminal out, the input terminals DC_in of the n power amplification units are connected in series, the output terminals out of the n power amplification units are connected in parallel, and the power amplification module is connected to a high-voltage DC power supply unit, where 0 < n ≤ 32, and n is a positive integer.

[0066] Each power amplifier unit includes a full-bridge inverter circuit, which includes an H-bridge circuit, an input capacitor C, a bypass switch K, and a transformer T. The two arms of the H-bridge circuit, the input capacitor C, and the bypass switch K are connected in parallel between the positive input terminal (DC_in+) and the negative input terminal (DC_in-). The two arms of the H-bridge circuit receive high-voltage direct current (DC) from the high-voltage DC power supply unit via the input terminal (DC_in). The two power switch units Q in the same arm are each connected to a driver module.

[0067] Each leg of the H-bridge circuit includes a first power switch unit Q1 and a second power switch unit Q2 connected in series. The gate of the first power switch unit Q1 is connected to the driver module, and the emitter of the first power switch unit Q1 is connected to the positive collector of the second power switch unit Q2. The collector of the first power switch unit Q1 is connected to the positive input terminal DC_in+. The gate of the second power switch unit Q2 is connected to the driver module, and the emitter of the second power switch unit Q2 is connected to the negative input terminal DC_in-. The emitter of the first power switch unit Q1 in one leg of the H-bridge circuit is also connected to the positive terminal of the primary winding of the transformer T, while the emitter of the first power switch unit Q1 in the other leg is also connected to the negative terminal of the primary winding of the transformer T. The two ends of the secondary winding of the transformer T are respectively connected to the positive output terminal out+ and the negative output terminal out- of the power amplifier module.

[0068] The controller comprises a sampling / buffering module, a timer, 2n PWM modulators, and a fault processing module. The fault processing module is electrically connected to the timer, the 2n PWM modulators, and the power amplification module respectively.

[0069] Each PWM modulator includes a counter and a comparator. The counter is connected to the timer and is used to receive the phase trigger signal TRG output by the timer. The comparator is electrically connected to the sampling / buffer module and the counter, respectively, and receives the triangular carrier output by the counter and the signal output by the sampling / buffer module.

[0070] In this embodiment, if Figures 2-4 As shown, the working process of the power amplifier of this application is:

[0071] The sampling / buffer module receives the input signal, performs digital quantization processing on the input signal, and then sends it to the comparator.

[0072] The timer receives the switching signal and generates 2n phase trigger signals TRG1, TRG2, TRG3...TRG2n with time intervals differing by T / 2n, and sends the 2n phase trigger signals to counter 1, counter 2, counter 3...counter 2n of the 2n PWM modulators respectively, where T is the carrier period of the triangular carrier of the counter.

[0073] Taking the PWM modulator 2n as an example, the counter 2n of the PWM modulator 2n receives the phase trigger signal TRGn transmitted by the timer and starts counting up from zero. When the count reaches the period count value, it counts down to zero. This cycle repeats to generate a triangular carrier 2n and sends the triangular carrier 2n to the comparator 2n.

[0074] Comparator 2n receives and compares the signal transmitted by the sampling / buffer module with the triangular carrier value transmitted by comparator 2n in real time. When the signal value is greater than the triangular carrier value, the PWM / 2n output terminal outputs a high-level modulation signal, and the / PWM2n output terminal outputs a low-level modulation signal. When the signal value is less than the triangular carrier value, the PWM / 2n output terminal outputs a low-level modulation signal, and the / PWM2n output terminal outputs a high-level modulation signal. The PWM / 2n modulation signal output by the comparator and the PWM / 2n modulation signal are transmitted as a set of PWM2n modulation signals to the power amplifier module through the driver module.

[0075] like Figure 4 As shown, the comparators of the 2n PWM modulators send 2n groups of PWM modulation signals, namely the first group of PWM modulation signals, the second group of PWM modulation signals, ... the 2nth group of PWM modulation signals, to the power amplification module through the driving module.

[0076] Each power amplifier unit in the power amplifier module receives two sets of PWM modulation signals. One arm of the power amplifier unit's H-bridge circuit receives one set of PWM modulation signals and transmits them to the positive terminal of the primary winding of transformer T, while the other arm receives one set of PWM modulation signals and transmits them to the negative terminal of the primary winding of transformer T. Under the excitation of high-voltage DC power, the secondary winding of transformer T outputs an amplified signal to the output of the power amplifier unit. This signal is then combined with the amplified signals output by other power amplifier units at the output of the power amplifier unit to produce a power-combined signal.

[0077] Specifically, such as Figure 2 As shown, taking any power amplifying unit a among the n power amplifying units as an example, one of the bridge arms of the power amplifying unit a receives the ath group of PWM modulation signals, the first power switch unit Q1 receives the PWM / a modulation signal of the ath group of PWM modulation signals, and the second power switch unit Q2 receives the / PWMa modulation signal of the ath group of PWM modulation signals; the other bridge arm of the power amplifying unit a receives the n+ath group of PWM modulation signals, the first power switch unit Q1 receives the PWM / n+a modulation signal of the n+ath group of PWM modulation signals, and the second power switch unit Q2 receives the / PWMn+a modulation signal of the n+ath group of PWM modulation signals.

[0078] The power amplification module sends the power-synthesized signal to the filtering module, and the filtering module performs filtering processing on the power-synthesized signal to obtain a high-power signal.

[0079] The status acquisition module collects the operating status of the driver module and the power amplifier module to obtain real-time fault information about the driver module and the power amplifier module. The module then sends this fault information to the controller's fault processing module. The fault information includes the number m of faulty power amplifier units in the power amplifier module and the fault location, where m is a positive integer less than n. Upon receiving the fault information from the status acquisition module, the fault processing module transmits a fault control signal.

[0080] like Figure 3 、 4 As shown, the fault processing module includes a phase shift control signal, an enable control signal EN and a fault bypass control signal.

[0081] The fault processing module sends a phase shift control signal to the timer, where the phase shift control signal includes the number m of faults in the power amplifier unit. The timer adjusts the phase trigger signal of the output channel according to the number m of faults in the power amplifier unit.

[0082] The fault processing module sends enable control signals E1, E2 to Em to the 2m PWM modulators corresponding to the m faulty power amplifying units respectively, and shields the 2m groups of PWM modulation signals corresponding to the m faulty power amplifying units.

[0083] The fault processing module sends a bypass control signal to the bypass switches K of the m faulty power amplifying units, the bypass switches K of the m faulty power amplifying units are closed, and the m faulty power amplifying units stop working.

[0084] It should be noted that, in this document, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that an article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such article or device. In the absence of further limitations, the elements defined by the phrase "includes..." do not exclude the presence of other identical elements in the article or device comprising the elements.

[0085] The above embodiments are intended to illustrate the technical solutions of the present invention and are not intended to limit the present invention. The present invention is described in detail with reference to the preferred embodiments only. It should be understood by those skilled in the art that the technical solutions of the present invention may be modified or replaced with equivalents without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications and replacements should be included within the scope of the claims of the present invention.

Claims

1. A power amplifier, characterized in that: The invention comprises a controller, a driving module, a power amplifier module and a filtering module. The controller is electrically connected to the power amplifier module through the driving module and transmits a PWM modulation signal. The output end of the power amplifier module is electrically connected to the filtering module. The power amplifier module comprises n power amplifier units, each of which comprises an input end and an output end. The input ends of the n power amplifier units are connected in series, and the output ends of the n power amplifier units are connected in parallel. The input end of the power amplifier module is connected to an external high-voltage DC power supply unit, where 1≤n≤32. The PWM modulation signal received by the power amplifier module enters the n power amplifier units for power amplification, and the power-amplified signal is output through the output ends of the n power amplifier units to achieve power synthesis. The power amplifier module is used to output the power-synthesized signal. Each of the power amplification units includes a full-bridge inverter circuit, each of which includes an H-bridge circuit, an input capacitor, a bypass switch, and a transformer; the H-bridge circuit is formed by four groups of power switch units with the same circuit structure connected in an H-bridge form, and each group of power switch units includes a power switch device; The input terminals of the H-bridge circuit and the input capacitor are connected in parallel between the positive electrode of the input terminal of the power amplifier module and the negative electrode of the input terminal of the power amplifier module; the bypass switch is connected in parallel with the input capacitor; The controller includes a sampling / buffering module, a timer, 2n PWM modulators and a fault processing module running in parallel under the same clock beat; The sampling / buffering module is used to receive an input signal, digitally quantize and buffer the input signal, and then transmit the input signal to the 2n PWM modulators; The timer is used to receive the start / stop signal and send 2n phase trigger signals with time intervals of T / 2n to the 2n PWM modulators, where T is the carrier period of the PWM modulator; The 2n PWM modulators are used to complete PWM modulation of the signal output by the sampling / buffering module; and are also used to control the carrier phase of the output PWM modulated signal according to the phase trigger signal after receiving the phase trigger signal; The fault processing module is used to obtain fault information of the power amplification unit in the power amplification module, send a fault bypass control signal to the bypass switch of the faulty power amplification unit, and send an output phase shift control signal and an enable control signal to the timer and the PWM modulator corresponding to the faulty power amplification unit respectively; Among them, the fault bypass control signal is used to close the bypass switch to stop the faulty power amplifier unit from working; the phase shift control signal includes the fault number of the power amplifier unit, so that the timer adjusts the number of phase trigger signals generated according to the fault number; the enable control signal is used to shield the PWM modulation signal output by the PWM modulator corresponding to the faulty power amplifier unit.

2. The power amplifier according to claim 1, wherein The controller is used to complete signal sampling / caching, and perform PWM pulse width modulation with 2n digital triangular carriers with the same frequency and a phase difference of π / n, to generate 2n groups of PWM modulation signals with the same frequency and a phase difference of π / n, and each group of PWM modulation signals includes two PWM modulation signals with complementary levels, and its duty cycle is proportional to the amplitude of the input signal.

3. The power amplifier according to claim 1, wherein The driving circuit module is located between the controller and the power amplifying module, and is used to receive the 2n groups of PWM modulation signals output by the controller and complete power amplification of the PWM modulation signals so as to drive the power amplifying module.

4. The power amplifier according to claim 1, wherein The H-bridge circuit receives high-voltage direct current from the high-voltage direct current power supply unit; The two power switch devices in the same bridge arm of the H-bridge circuit receive a set of PWM modulation signals output by the driving circuit module, so as to achieve power amplification of the output signal of the driving module.

5. The power amplifier according to claim 1, wherein The transformer includes a primary winding and a secondary winding, and the two output ends of the H-bridge circuit are respectively connected to the two ends of the primary winding of the transformer; the two ends of the secondary winding of the transformer are respectively connected to the positive pole of the output end of the power amplifier module and the negative pole of the output end of the power amplifier module.

6. The power amplifier according to claim 1, wherein: The power amplifier also includes a status acquisition module, which is electrically connected to the controller, the driving module and the power amplification module respectively. The status acquisition module is used to collect the working status of the driving module and the power amplification module, and output the fault information to the fault processing module of the controller according to the working status. The fault information includes the number and fault location of the power amplification unit in the power amplification module.

7. The power amplifier according to claim 1, wherein: Each of the PWM modulators includes a counter and a comparator arranged in a one-to-one correspondence, wherein the counter is activated by the corresponding phase trigger signal output by the timer to generate a periodic digital triangular modulated carrier; the comparator is used to compare the count value of the counter with the digital quantization value of the input signal in real time and output the PWM modulated signal.

8. The power amplifier according to claim 2, wherein: The step of pulse width modulating the input signal to generate 2n groups of PWM modulation signals includes: The input signal is pulse-width modulated with 2n digital triangular modulation carriers with the same frequency and a phase difference of π / n to generate 2n groups of PWM modulation signals.

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