阅读说明：本技术 一种用于改善功率变换器性能的系统 (It is a kind of for improving the system of power inverter performance ) 是由 陈杰 于 2018-05-23 设计创作，主要内容包括：本发明公开了一种用于改善功率变换器性能的系统,包括功率变换器和控制系统,所述控制系统包括数字参考信号发生器、F/V变换器、第一PI控制器、控制信号组合器、PCM控制器和第二PI控制器；本发明在最大峰值功率跟踪操作模式和输出电压操作模式下操作,通过数字参考信号以及第一PI控制器和第二PI控制器,可以通过控制系统实现数字和模拟控制的组合,从而增加与功率变换器控制系统一起使用的功率变换器的性能。(The invention discloses a kind of for improving the system of power inverter performance, including power inverter and control system, the control system includes digital reference signal generator, F/V converter, the first PI controller, control signal combiner, PCM controller and the 2nd PI controller；The present invention makees in maximum peak power tracking modes of operation and output voltage mode of operation, pass through digital reference signal and the first PI controller and the 2nd PI controller, the combination of number and simulation control can be realized by control system, to increase the performance for the power inverter being used together with power inverter control system.)

1. a kind of for improving the system of power inverter performance, which is characterized in that including power inverter and control system, institute Stating control system includes digital reference signal generator, F/V converter, the first PI controller, control signal combiner, PCM control Device processed and the 2nd PI controller；The digital reference signal generator is configured as receiving output voltage from power inverter, and And the operation mode of the digital reference signal generator based on output voltage and currently selected and in MPPT operation mode and output It is selected between voltage control operation mode；The digital reference signal generator generates a reference frequency, this is with reference to frequency Rate is received by F/V converter, and reference frequency is transformed to reference input voltage by F/V converter, and reference input voltage is provided to First PI controller, while the first PI controller receives input voltage, output first control signal to control signal combiner First input end, the 2nd PI controller receive reference output voltage and output voltage, and output second control signal is to controlling signal Second input terminal of combiner, the output end for controlling signal combiner are coupled to PCM controller, the output end of the PCM controller It is coupled to power inverter.

2. according to claim 1 a kind of for improving the system of power inverter performance, which is characterized in that the power Converter is configured as receiving input voltage and input current and provides output voltage.

Technical field

The present invention relates to electrical equipment technical fields, and in particular to a kind of for improving the system of power inverter performance.

Background technique

In the presence of the several different types of control systems that can be used together with power inverter.One for power inverter The control system of a common type is peak-current mode (PCM) control system, usually utilizes analog component that will control signal Being provided to power inverter makes to reach desired output performance.Although in numerous applications usually effectively, when using such as It is difficult to when the variable power supply of renewable energy (for example, photocell, fuel cell and wind-driven generator) using PCM control system. Therefore, replaced PCM control system that maximum peak power tracking (MPPT) control system is utilized in such applications.

Due to the property of the calculating executed in MPPT control system, this control system is often in such as microprocessor And/or implement in the digital display circuit of digital signal processor (DSP).In general, MPPT control system uses disturbance observation controlling party Case is provided to power inverter to control signal, so that the output in power inverter reaches the power of maximum possible Amount.However, digital (for example, based on DSP's) MPPT control system is for such as when compared with conventional analog control system The external event of load impedance variation is generally subjected to reduced bandwidth and relatively slow transient response time.Further, with Conventional analog control system is compared, and digital MPPT control system is designing and implementing the aspect opposite consuming time.

Accordingly, there exist simultaneously include improved transient response time and wide bandwidth to that can implement MPPT control program The needs of control system for power inverter.

Summary of the invention

For above-mentioned technical problem of the existing technology, the present invention has deducted a percentage a kind of for improving power inverter performance System.

The present invention is achieved through the following technical solutions:

It is a kind of for improving the system of power inverter performance, including power inverter and control system, the control system System includes digital reference signal generator, F/V converter, the first PI controller, control signal combiner, PCM controller and the Two PI controllers；The digital reference signal generator is configured as receiving output voltage from power inverter, and based on defeated Out the operation mode of voltage and the digital reference signal generator currently selected and in MPPT operation mode and output voltage control It is selected between operation mode；The digital reference signal generator generates a reference frequency, which is become by F/V Parallel operation receives, and reference frequency is transformed to reference input voltage by F/V converter, and reference input voltage is provided to the first PI control Device, while the first PI controller receives input voltage, output first control signal extremely controls the first input end of signal combiner, 2nd PI controller receives reference output voltage and output voltage, output second control signal to the second of control signal combiner Input terminal, the output end for controlling signal combiner are coupled to PCM controller, and the output end of the PCM controller is coupled to power change Parallel operation.

Further, the power inverter is configured as receiving input voltage and input current and provides output voltage.

The present invention has the advantage that and the utility model has the advantages that

By the present invention in that with digital reference signal as described above and the first PI controller and the 2nd PI controller, it can With the combination controlled by control system realization number and simulation, thus what increase was used together with power inverter control system The performance of power inverter.

Detailed description of the invention

Attached drawing described herein is used to provide to further understand the embodiment of the present invention, constitutes one of the application Point, do not constitute the restriction to the embodiment of the present invention.In the accompanying drawings:

Fig. 1 shows the system block diagram of an embodiment of the invention.

Fig. 2 shows the principles of the first PI controller and the 2nd PI controller in system described in Fig. 1 of the invention Block diagram.

Fig. 3 shows the stream of tracking (MPPT) control method of maximum peak power in accordance with one embodiment of the present disclosure Cheng Tu.

Fig. 4 shows combined MPPT control method and output voltage control side in accordance with one embodiment of the present disclosure The flow chart of method.

Specific embodiment

To make the objectives, technical solutions, and advantages of the present invention clearer, below with reference to embodiment and attached drawing, to this Invention is described in further detail, and exemplary embodiment of the invention and its explanation for explaining only the invention, are not made For limitation of the invention.

Fig. 1 shows the system 10 for being used to improve power inverter performance in accordance with one embodiment of the present disclosure.It should System 10 includes power inverter 12 and power inverter control system 14.Power inverter 12 is configured as receiving input voltage The output voltage V_OUT that V_IN and offer have been conditioned and/or have converted.Power inverter 12 can be any kind of function Rate converter, such as, booster converter, buck converter, buck-boost converter etc..Power inverter control system 14 is configured To receive input voltage V_IN, input current I_IN, output voltage V_OUT and output electric current I_OUT, and will be one or more Power inverter control signal PCC is provided to power inverter 12 to control its operation.

Power inverter control system 14 includes digital reference signal generator 16, which is matched Be set to receive input voltage V_IN, via input current sensor 18 input current I_IN and output voltage V_OUT and An offer reference frequency in (MPPT) control program or output voltage control scheme is tracked based on maximum peak power REF_F.Reference frequency REF_F is received by voltage to frequency (F/V) converter 20, and voltage to frequency (F/V) converter is by reference frequency REF_F is transformed to reference input voltage REF_IN.Reference input voltage REF_IN is provided to the first proportional integration (PI) control Reference input voltage REF_IN is used together by device 22 in the first pi controller with input voltage V_IN, by One PI control signal PI_CONT1 is provided to control signal combiner 24.

2nd PI controller 26 receives reference output voltage REF_OUT and output voltage V_OUT, wherein with reference to output electricity Pressing REF_OUT is the constant reference voltage that can be provided by many external power supplies.2nd PI controller 26 is used with reference to output Voltage REF_OUT and output voltage V_OUT provides the 2nd PI and controls signal PI_CONT2, and the 2nd PI controls signal PI_CONT2 It is provided to control signal combiner 24.The output end of control signal combiner 24 is coupled to peak-current mode (PCM) control Device 28, the PCM controller transfer to be coupled to power inverter 12.PCM controller 28 is configured as via output current sensor 30 receive output electric current I_OUT and receive control signal from control signal combiner 24, and will be one or more based on this Power inverter control signal PCC is provided to power inverter 12.Power inverter, which controls signal PCC, can control output voltage V_ The amplitude of the amplitude of OUT, the amplitude for exporting electric current I_OUT or the two.In some embodiments, PCM controller 28 can The many pre-packaged power converter controllers operated with being often based on single control signal input.For example, PCM controller 28 can be the Part No. UCC28220 of the Texas Instruments from Dallas, Texas.

As described above, digital reference signal generator 16 is configured as operating in MPPT operation mode and output voltage control It is operated under mode.Under the MPPT operation mode of digital reference signal generator 16, digital reference signal generator 16 is configured To provide reference frequency REF_F based on input voltage V_IN and input current I_IN, and therefore provide reference input voltage REF_IN.Under the MPPT operation mode of digital reference signal generator 16, control signal combiner 24, which controls the first PI, to be believed Number PI_CONT1 is provided to PCM controller 28.

Under output voltage control operation mode, digital reference signal generator 16 is configured to supply constant reference frequency Rate REF_F, so that reference input voltage REF_IN is constant signal.Specifically, the offer of digital reference signal generator 16 is compared High reference frequency REF_F (for example, 4kHz) believes to drive reference input voltage REF_IN and therefore to control the first PI Number PI_CONT1 drives to its maximum value.As discussed in detail below, the first PI control signal PI_CONT1 is driven to it Maximum value make control signal combiner 24 by the 2nd PI control signal PI_CONT2 be provided to PCM controller 28, such as it is following in detail Carefully discuss.Therefore, power inverter control system 14 can change from MPPT control program to output voltage control scheme.

Fig. 2 shows the details of control signal combiner 24 in accordance with one embodiment of the present disclosure.For context Also show the first PI controller 22 and the 2nd PI controller 26.As shown in Fig. 2, the output end of the first PI controller 22 is coupled to Control the first input end 32 of signal combiner 24.The output end of 2nd PI controller 26 is coupled to control signal combiner 24 Second input terminal 34.Controlling signal combiner 24 further comprises the output end 36 for being coupled to the input terminal of PCM controller 28.Such as Upper described, control signal combiner 24 controls the first PI in signal PI_CONT1 or the 2nd PI control signal PI_CONT2 One is provided to PCM controller 28.The first input end 32 of control signal combiner 24 is coupled to defeated via first resistor device R1 Outlet 36.Further, the output end 36 for controlling signal combiner 24 is coupled to ground via second resistor R2.Control signal Diode 38 in combiner 24 includes being coupled to the anode of output end 36 and to be coupled to second via 3rd resistor device R3 defeated Enter the cathode at end 34.Further, the cathode of diode 38 is coupled to ground via the 4th resistor R4.

In operation, as discussed in detail below, under the MPPT operation mode of power inverter control system 14, number Reference signal generator 16 provides reference frequency using input voltage V_IN and input current I_IN according to MPPT control program REF_F.Under the MPPT operation mode of power inverter control system 14, because being no more than the threshold voltage of diode 38, institute Reverse bias is kept with diode 38.Therefore, only the first PI controls signal PI_CONT1 and is provided to PCM controller 28.In Under the output voltage control operation mode of power inverter control system 14, digital reference signal generator 16 is by reference frequency REF_F is provided as fixed frequency.Specifically, digital reference signal generator 16 provides high frequency fixed signal (for example, 4kHZ is sinusoidal Signal) it is used as reference frequency REF_F, which drives the first PI control signal PI_CONT1 to maximum value.The The maximum value of one PI control signal PI_CONT1 makes diode 38 become forward bias.When diode 38 becomes forward bias, The 2nd PI control signal PI_CONT2 modulation based on output voltage V_OUT passes through first resistor device R1's and second resistor R2 Electric current, the signal which is provided to PCM controller 28 make PCM controller 28 via the output electricity of power inverter 12 It presses V_OUT and controls.

In one embodiment, diode 38 is low pressure drop diode, so that the forward voltage drop for passing through diode is less than About 0.1V.In various embodiments, diode 38 can be silicon (Si) Schottky diode.When diode 38 is as described above Output voltage control mode under when becoming forward bias, the voltage (ideally) across the 4th resistor R4 should be believed with control The voltage of the output end 36 of number combiner 24 is identical.However, the pressure drop for passing through diode 38 has been added to the voltage.This is two poles The reason of pipe 38 should be the low pressure drop diode for minimizing the error this.

Fig. 3 is to show the flow chart of MPPT control program as described above in accordance with one embodiment of the present disclosure. Specifically, Fig. 3 shows the disturbance that can be used in various embodiments of the present disclosure and observation (P&O) MPPT control program. It can be provided by digital reference signal generator 16 using MPPT control program and be based on input voltage V_IN and input current I_IN Reference frequency REF_F.Firstly, Instantaneous input power P_IN (N) is calculated as P_IN (N)=V_IN (N) * I_IN (N) (step 100).Then determine whether Instantaneous input power P_IN (N) is greater than input power P_IN (N-1) (step of upper one calculating 102).If Instantaneous input power P_IN (N) is greater than the input power P_IN (N-1) of upper one calculating, it is determined that instantaneous reference Whether frequency REF_F (N) is greater than a upper reference frequency REF_F (N-1) (step 104).If instantaneous reference frequency REF_F (N) it is greater than a upper reference frequency REF_F (N-1), then reference frequency REF_F increases specific quantity Δ F (step 106).If wink When reference frequency REF_F (N) be less than a upper reference frequency REF_F (N-1), then reference frequency REF_F reduce specific quantity Δ F (step 108).If Instantaneous input power P_IN (N) is less than the input power P_IN (N-1) of upper one calculating, it is determined that instantaneous Whether reference frequency REF_F (N) is greater than a upper reference frequency REF_F (N-1) (step 110).If instantaneous reference frequency REF_F (N) is greater than a upper reference frequency REF_F (N-1), then reference frequency REF_F reduces specific quantity Δ F (step 112).Such as Fruit instantaneous reference frequency REF_F (N) is less than a upper reference frequency REF_F (N-1), then reference frequency REF_F increases specific quantity Δ F (step 114).As discussed above, reference frequency REF_F is transformed to reference input voltage REF_ by F/V converter 20 IN.First PI controller 22 is then based on reference input voltage REF_IN and provides the first PI control signal PI_CONT1, so that PCM Controller 28 is based on MPPT control program and provides power inverter control signal PCC.

Although showing P&OMPPT control program in Fig. 3, can be used without departing from the principle of the disclosure Any MPPT control program is in order to provide reference frequency REF_F.It, can be by for example, without departing from the principle of the disclosure Digital reference signal generator 16 uses MPPT control program, the current scanning MPPT control program, constant electricity for increasing electric conductivity Press MPPT control program etc..

Under the output voltage control mode of power inverter control system 14, the 2nd PI based on output voltage OUT_V Control signal PI_CONT2 is provided to PCM controller 28.Therefore, PCM controller 28 will be mentioned based on conventional PCM control program Signal PCC is controlled for power inverter, skilled persons will understand that their details.

Fig. 4 is to show the digital reference signal switched between MPPT operation mode and output voltage control operation mode The flow chart of the decision process of generator 16.Firstly, currently being operated under which mode based on digital reference signal generator 16 Determined (step 200).If digital reference signal generator 16 is currently made in output voltage control mode of operation, Determine whether output voltage V_OUT is less than scheduled under-voltage V_UV (step 202).If output voltage V_OUT is less than predetermined Under-voltage V_UV, then the operation mode of digital reference signal generator 16 changes to MPPT from output voltage control operation mode and grasps Operation mode (step 204).If digital reference signal generator 16 is currently made in MPPT mode of operation, it is determined that output electricity Press V_OUT whether on predetermined overvoltage V_OV (step 206).If output voltage V_OUT predetermined overvoltage V_OV it On, then the operation mode of digital reference signal generator 16 changes from MPPT operation mode to output voltage control operation mode (step 208).Therefore, digital reference signal generator 16 can be with switch mode to control power inverter control as needed System 14.

Predetermined under-voltage V_UV and predetermined overvoltage V_OV can be adjusted based on the specific requirement of power inverter 12. Further, without departing from the principle of the disclosure, digital reference signal generator 16 may be used at operation mode it Between any appropriate method for switching.

Above-described specific embodiment has carried out further the purpose of the present invention, technical scheme and beneficial effects It is described in detail, it should be understood that being not intended to limit the present invention the foregoing is merely a specific embodiment of the invention Protection scope, all within the spirits and principles of the present invention, any modification, equivalent substitution, improvement and etc. done should all include Within protection scope of the present invention.