Carrier modulation method and optical storage integrated system

Abstract

The invention relates to a carrier modulation method and an optical storage integrated system, and relates to the technical field of carrier modulation. A specific embodiment of the method comprises the following steps: respectively acquiring carrier signals of a plurality of DC / DC converters in the optical storage integrated system, taking one of the carrier signals as a reference carrier signal and the rest as carrier signals to be controlled, and calculating a carrier phase difference value between the carrier signals to be controlled and the reference carrier signal; and calculating an error value between the carrier phase difference value and a carrier phase preset difference value, and adjusting the carrier signal to be controlled according to the error value and an error value threshold value so as to realize carrier modulation on the DC / DC converter. According to the embodiment of the invention, automatic control of carrier wave interleaving parallel connection is realized, the situation of direct connection of a switching circuit in a carrier wave modulation process is avoided, the carrier wave modulation effect is improved, and the application scene of a carrier wave modulation scheme is expanded.

Description

Technical Field

[0001] The present application relates to the field of carrier modulation technology, and in particular to a carrier modulation method and an integrated optical-storage system. Background Art

[0002] The photovoltaic storage integrated system combines photovoltaic power generation and energy storage technology to achieve the generation, storage and use of electric energy and improve the energy utilization efficiency of the system. With the increase of system capacity, existing equipment mostly adopts a circuit topology of multiple photovoltaics and multiple batteries in parallel, that is, the boost circuit drivers of multiple photovoltaic components are in an interlaced parallel form, and the boost and buck circuit drivers of multiple energy storage batteries are in an interlaced parallel form. For the carrier modulation of the multi-drive interlaced parallel system, the relevant technology is generally realized by configuring the synchronization function of the chip, that is, TBPHS (Time Base Phase Shift, phase register value) is directly loaded into TBCTR (Time Base Counter, time base counter) at the synchronization moment. This method is simple to configure and widely used, but directly loading a new TBPHS value at the synchronization moment may cause a sudden change in the time base counter TBCTR, which in turn affects the switching state of the switch in the converter, and sometimes even causes a direct-through problem in the switch circuit, resulting in poor carrier modulation effect.

[0003] Currently, no effective solution has been proposed to solve the problems that the count value in the carrier modulation implemented based on the chip synchronization function in the related technology is prone to sudden changes, there is a risk of direct connection of the switching circuit, and the carrier modulation effect is poor. Summary of the invention

[0004] The carrier modulation method and integrated optical-storage system provided by the embodiments of the present invention at least solve the problems in the related art that the count value is prone to sudden changes during the carrier modulation process, there is a risk of the switch circuit being directly connected, and the carrier modulation effect is poor.

[0005] In order to solve the above problem, one aspect of an embodiment of the present invention provides a carrier modulation method, including:

[0006] The carrier signals of multiple DC / DC converters in the integrated photovoltaic and energy storage system are respectively obtained, one of which is used as a reference carrier signal, and the rest are carrier signals to be controlled, and the carrier phase difference between the carrier signal to be controlled and the reference carrier signal is calculated;

[0007] The error value between the carrier phase difference value and the carrier phase preset difference value is calculated, and the carrier signal to be controlled is adjusted according to the error value and the error value threshold value to realize carrier modulation of the DC / DC converter.

[0008] In some embodiments, the photovoltaic-storage integrated system includes a multi-channel photovoltaic power management circuit and a multi-channel energy storage battery management circuit, the photovoltaic power management circuit includes photovoltaic modules and DC / DC converters connected in series, and the energy storage battery management circuit includes energy storage batteries and DC / DC converters connected in series; the method also includes:

[0009] For a multi-channel photovoltaic power management circuit, a first carrier phase difference and a first error value are calculated respectively, and a first carrier signal to be controlled is adjusted according to the first error value and the first error value threshold; wherein the first carrier phase difference refers to a carrier phase difference between a first carrier signal to be controlled and a first reference carrier signal in the multi-channel photovoltaic power management circuit;

[0010] For a multi-channel energy storage battery management circuit, a second carrier phase difference and a second error value are calculated respectively, and the second carrier signal to be controlled is adjusted according to the second error value and the second error value threshold; wherein the second carrier phase difference refers to the carrier phase difference between the second carrier signal to be controlled and the second reference carrier signal in the multi-channel energy storage battery management circuit.

[0011] In some embodiments, the step of adjusting the carrier signal to be controlled according to the error value and the error value threshold includes:

[0012] Determine a target carrier cycle adjustment coefficient according to the error value and the relationship curve, and determine a carrier cycle adjustment value according to the carrier cycle adjustment threshold and the target carrier cycle adjustment coefficient; wherein the relationship curve includes a mapping relationship between the error value and the carrier cycle adjustment coefficient;

[0013] The carrier signal to be controlled is adjusted according to the carrier period adjustment value.

[0014] In some of the embodiments, after the step of determining the carrier period adjustment value, the method further includes:

[0015] The carrier period frequency jitter step cumulative value is obtained, and the carrier period of the carrier signal to be controlled is updated according to the carrier period frequency jitter step cumulative value and the carrier period adjustment value.

[0016] In some of the embodiments, the method further comprises the step of determining a preset carrier phase difference:

[0017] Obtaining the layout information of multiple photovoltaic power management circuits and multiple energy storage battery management circuits in the photovoltaic and energy storage integrated system;

[0018] A digital signal processing device is used to determine, based on the arrangement information, a first carrier phase preset difference between a first carrier signal to be controlled and a first reference carrier signal in a multi-channel photovoltaic power management circuit; and a second carrier phase preset difference between a second carrier signal to be controlled and a second reference carrier signal in a multi-channel energy storage battery management circuit.

[0019] In some embodiments, the step of calculating the carrier phase difference between the carrier signal to be controlled and the reference carrier signal includes:

[0020] Based on the time base counter in the digital signal processing device, a first time base count value and a second time base count value corresponding to the carrier signal to be controlled are respectively obtained, and the carrier phase difference value is calculated according to the first time base count value and the second time base count value.

[0021] In some of these embodiments, the method further comprises:

[0022] At least one external interface is configured to receive a carrier modulation requirement based on the external interface, and perform carrier modulation on the integrated optical storage system according to the carrier modulation requirement.

[0023] In order to solve the above problems, one aspect of an embodiment of the present invention provides a photovoltaic storage integrated system, the system includes a multi-channel photovoltaic power management circuit, a multi-channel energy storage battery management circuit, a DC / AC converter, and a digital signal processing device; wherein,

[0024] The photovoltaic power management circuit includes photovoltaic modules and DC / DC converters connected in series;

[0025] The energy storage battery management circuit includes an energy storage battery and a DC / DC converter connected in series;

[0026] After multiple photovoltaic power management circuits and multiple energy storage battery management circuits are connected in parallel to the DC bus, they are connected to the AC grid via a DC / AC converter;

[0027] The digital signal processing device is connected to the control port of the DC / DC converter and is used to execute any of the above carrier modulation methods.

[0028] In some of the embodiments, the digital signal processing device also includes a frequency jittering control module, which is used to: obtain a cumulative value of the carrier period frequency jittering step length, and update the carrier period of the controlled carrier signal according to the cumulative value of the carrier period frequency jittering step length.

[0029] In some of the embodiments, the digital signal processing device further includes a plurality of external interfaces. The digital signal processing device receives carrier modulation requirements based on the external interfaces, and performs carrier modulation on the integrated optical storage system according to the carrier modulation requirements.

[0030] The beneficial effects of the embodiments of the present invention are as follows: by respectively acquiring carrier signals of multiple DC / DC converters in the integrated optical storage system, one of which is used as the reference carrier signal and the rest are the carrier signals to be controlled, the carrier phase difference between the carrier signal to be controlled and the reference carrier signal is calculated; the error value between the carrier phase difference and the preset carrier phase difference is calculated, and the carrier signal to be controlled is adjusted according to the error value and the error value threshold, so as to realize the technical means of carrier modulation of the DC / DC converter, and overcome the problem that the counter is prone to mutation due to the synchronization function of the configuration chip directly loading the new TBPHS value at the synchronization moment, thereby affecting the switching state of the switch in the converter, and sometimes even causing the problem of direct conduction of the switch circuit, and the problem of poor carrier modulation effect, and realizes the real-time detection of the carrier phase difference between the carrier signal to be controlled and the reference carrier signal without using an additionally configured chip, and adaptively adjusts the carrier signal to be controlled based on the detection result and the preset carrier phase difference, avoiding the direct conduction risk of the switch circuit caused by the chip synchronization function, achieving the technical effect of improving the carrier modulation effect, realizing the automatic control of the carrier interleaved parallel connection and the adaptive adjustment of the carrier modulation, and expanding the applicable scenarios of the carrier modulation.

[0031] The details of one or more embodiments of the invention are set forth in the following drawings and description so that other features, objects, and advantages of the invention are more readily apparent. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art descriptions. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other embodiments can be obtained based on these drawings without creative work.

[0033] Figure 1 It is a flowchart of a carrier modulation method according to an embodiment of the present invention.

[0034] Figure 2 It is a schematic diagram of adjusting the carrier period of a carrier signal to be controlled according to an embodiment of the present invention.

[0035] Figure 3 It is a schematic diagram of a reference carrier and a carrier to be controlled that are phase-staggered and satisfy a carrier phase difference according to an embodiment of the present invention.

[0036] Figure 4 It is a schematic diagram of a relationship curve between an error value and a carrier cycle adjustment coefficient according to an embodiment of the present invention.

[0037] Figure 5 A schematic diagram of a photovoltaic-storage integrated system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0038] Embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although certain embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be construed as being limited to the embodiments described herein, which are instead provided for a more thorough and complete understanding of the present invention. It should be understood that the drawings and embodiments of the present invention are only for exemplary purposes and are not intended to limit the scope of protection of the present invention.

[0039] In the photovoltaic storage integrated system in the related art, a circuit topology of multiple photovoltaic modules and multiple energy storage batteries in parallel is often used. Specifically, multiple independent DC / DC converters are used, and each DC / DC converter is responsible for processing one photovoltaic module input or energy storage battery output. After multiple DC / DC converters are staggered and connected in parallel to the DC bus, they are connected to the AC power grid via the DC / AC converter on the inverter. In order to coordinate and control the duty cycle of the switching devices in each converter, the related art is generally implemented by configuring the synchronization function of the chip, that is, TBPHS (Time Base Phase Shift, phase register value) is directly loaded into TBCTR (Time Base Counter, time base counter) at the synchronization moment. This method is simple to configure and widely used, but directly loading a new TBPHS value at the synchronization moment may cause a sudden change in the time base counter TBCTR, which in turn affects the switching state of the switch in the converter, and sometimes even causes a problem of direct connection of the switching circuit, and the carrier modulation effect is poor.

[0040] In order to solve the above problems, the embodiment of the present invention provides a carrier modulation method, such as Figure 1 As shown, the carrier modulation method mainly includes:

[0041] Step S101, respectively obtain carrier signals of multiple DC / DC converters in the photovoltaic energy storage integrated system, take one of them as the reference carrier signal, and the rest as the carrier signals to be controlled, and calculate the carrier phase difference between the carrier signal to be controlled and the reference carrier signal.

[0042] Among them, the multi-channel photovoltaic power management circuit and the multi-channel energy storage battery management circuit in the photovoltaic storage integrated system provided by the embodiment of the present invention are arranged in parallel in an interlaced manner, so that the load of each converter can be balanced and the peak current of a single converter can be reduced, thereby reducing thermal stress, simplifying the heat dissipation design, and improving the thermal stability of the system. Furthermore, through the carrier interlaced parallel control, the output current or voltage ripples of multiple DC / DC converters can be staggered in time. When these ripples are superimposed, they will cancel each other out, thereby significantly reducing the output ripple of the entire system, thereby improving the power quality and reducing the impact on the power grid. At the same time, it is also beneficial to extend the battery life and protect sensitive loads.

[0043] Through the above-mentioned settings, the embodiment of the present invention realizes real-time detection of the carrier phase difference between the carrier signal to be controlled and the reference carrier signal without using an additionally configured chip, and adaptively adjusts the carrier signal to be controlled based on the detection result and the preset difference of the carrier phase, thereby avoiding the direct-through risk of the switching circuit caused by the chip synchronization function, improving the carrier modulation effect, realizing the automatic control of the carrier interleaved parallel connection and the adaptive adjustment of the carrier modulation, and expanding the technical effect of the applicable scenarios of the carrier modulation.

[0044] In some embodiments, the above-mentioned photovoltaic storage integrated system includes multiple photovoltaic power management circuits and multiple energy storage battery management circuits, the photovoltaic power management circuit includes photovoltaic components and DC / DC converters connected in series, and the energy storage battery management circuit includes energy storage batteries and DC / DC converters connected in series; the above-mentioned method also includes: for the multiple photovoltaic power management circuits, respectively calculating the first carrier phase difference and the first error value, and adjusting the first carrier signal to be controlled according to the first error value and the first error value threshold; wherein the first carrier phase difference refers to the carrier phase difference between the first carrier signal to be controlled and the first reference carrier signal in the multiple photovoltaic power management circuits; for the multiple energy storage battery management circuits, respectively calculating the second carrier phase difference and the second error value, and adjusting the second carrier signal to be controlled according to the second error value and the second error value threshold; wherein the second carrier phase difference refers to the carrier phase difference between the second carrier signal to be controlled and the second reference carrier signal in the multiple energy storage battery management circuits.

[0045] By independently controlling the carrier phase of the DC / DC converters in the multi-channel photovoltaic power management circuit and the DC / DC converters in the multi-channel energy storage battery management circuit, the duty cycle of each DC / DC converter can be better adjusted, the ripple of the output voltage and current can be reduced, and the power quality can be improved; it can also more effectively match the input characteristics and output requirements of each other to maximize energy conversion. In addition, the independent control mechanism also helps to achieve fault isolation and avoid mutual influence between the photovoltaic power management circuit and the energy storage battery management circuit.

[0046] In some of the embodiments, the step of calculating the carrier phase difference between the carrier signal to be controlled and the reference carrier signal includes: based on the time base counter in the digital signal processing device, respectively obtaining the first time base count value and the second time base count value corresponding to the carrier signal to be controlled, and calculating the carrier phase difference according to the first time base count value and the second time base count value.

[0047] By using the TBCTR value provided by the EPWM (Enhanced Pulse Width Modulation) module inside the DSP (Digital Signal Processor), the phase difference between the two carrier signals can be accurately calculated, ensuring the precise execution of control instructions, improving the stability and response speed of the system, simplifying the design of the control algorithm, and helping to improve the efficiency of carrier modulation.

[0048] According to a specific implementation of an embodiment of the present invention, in the EPWM module of the DSP, the carrier signal can be configured in the form of a triangular wave or a sawtooth wave, which is mainly achieved by adjusting the counting mode of the time base counter TBCTR. In the Up-Down counting mode, the counting direction of TBCTR is indicated by the CTRDIR signal. When CTRDIR=0, it means that TBCTR is in a downward counting state, that is, counting from the maximum value to the minimum value. In order to convert the triangular wave into a sawtooth wave, we can fix the counting direction to one direction (for example, always counting down) and reset the value of TBCTR when it reaches a certain threshold, instead of letting it naturally drop to the minimum value and then reverse the direction.

[0049] Based on the TBCTR value of the time base counter and the direction signal CTRDIR, when the carrier is in down counting (CTRDIR = 0),

[0050] T ctrl，调整后 =2*P base -T ctrl，调整前

[0051] In the formula, T represents the carrier TBCTR signal, P represents the TBPRD signal, the subscript Base represents the base carrier, and the subscript Ctrl represents the carrier to be controlled. Since in the Up-Down counting mode, the counter will reverse direction after reaching the upper limit of the period, count down from the maximum value until it reaches 0 again, and then continue to count up. Here, P_base can be regarded as half of the period, because in the Up-Down counting mode, the counter will experience two counts: one up and one down, and P_base can help determine the direction and position of the counter. T ctrl，调整后Represents the cycle count value of the carrier signal to be controlled after the adjustment, that is, when the carrier signal to be controlled will start a new cycle count after the phase adjustment. ctrl，调整前 Represents the cycle count value of the carrier signal to be controlled before adjustment, that is, the current cycle count value.

[0052] The above formula actually adjusts the phase based on the principle of origin symmetry. If we regard half of the cycle as the origin, then the count values ​​on both sides of the origin are symmetric about the origin. For example, if half of the cycle is 50, then the value 50 when counting up and the value 50 when counting down are symmetric about half of the cycle.

[0053] After the calculation method of the carrier signal to be controlled is determined based on the above, the current count difference between the carrier signal to be controlled and the reference carrier signal can be calculated, which is:

[0054] ΔT=T base -T ctrl

[0055] Furthermore, the carrier phase difference can be calculated based on the calculated difference:

[0056] Δθ=ΔT / 2P base

[0057] The phase difference signal can be used in the subsequent carrier modulation, or the count difference signal can be directly used to omit the phase difference calculation process to further improve the carrier modulation efficiency.

[0058] Step S102, calculating the error value between the carrier phase difference value and the carrier phase preset difference value, and adjusting the carrier signal to be controlled according to the error value and the error value threshold value to achieve carrier modulation of the DC / DC converter.

[0059] By calculating the error value between the carrier phase difference (actual difference) and the carrier phase preset difference (preset difference), the carrier phase of the carrier signal to be controlled can be accurately adjusted to ensure that the carrier phase difference meets the expected setting, and finally output a multi-channel carrier signal that meets the phase difference requirements, achieving precise carrier interleaving parallel control, thereby improving the overall efficiency and stability of the system. When the system load or working conditions change, by quickly calculating the error value and adjusting the carrier signal, the system can quickly achieve dynamic response and maintain a stable output result (adjusted carrier signal), improving the carrier modulation effect of the DC / DC converter and expanding the applicable scenarios of the carrier modulation method.

[0060] According to a specific implementation of the embodiment of the present invention, when the carriers are interlaced in parallel, the count difference between each carrier signal to be controlled and the reference carrier signal has a standard value ΔT ref(According to the above statement, it can be expressed by count difference or carrier phase difference.) When the carrier phase difference meets the requirements, the count differences should meet the following requirements:

[0061] Δε=ΔT-ΔT rwf ; Δε∈[-ε,ε]

[0062] Wherein, ε represents the allowable carrier interleaving control error (ie, the upper and lower limits of the error value threshold), and Δε represents the difference between the detected count difference and the standard count difference (ie, the above-mentioned error value).

[0063] In some embodiments, the method further includes a step of determining a preset carrier phase difference: obtaining layout information of multiple photovoltaic power management circuits and multiple energy storage battery management circuits in a photovoltaic and energy storage integrated system; determining, by a digital signal processing device, a first preset carrier phase difference between a first carrier signal to be controlled and a first reference carrier signal in the multiple photovoltaic power management circuits based on the layout information; and determining a second preset carrier phase difference between a second carrier signal to be controlled and a second reference carrier signal in the multiple energy storage battery management circuits.

[0064] The embodiment of the present invention provides an EPWM module in a DSP to generate a precisely controllable pulse width modulation (PWM) signal, thereby realizing carrier modulation of a multi-channel converter. In order to achieve a better carrier modulation effect, it is necessary to dynamically detect the carrier signal and the carrier phase difference, so as to determine the carrier signal adjustment strategy according to the comparison result of the carrier phase preset difference and the carrier phase difference. The DSP determines the optimal carrier phase preset difference in advance based on the system layout conditions such as the physical layout, electrical connection and system configuration to adapt to the specific system architecture and operation requirements. At the same time, the correct carrier phase preset difference helps to reduce the circulating current between parallel DC / DC converters, reduce losses and improve the efficiency of the entire system. By optimizing the carrier phase difference, the ripple of the output voltage and current can also be reduced, and the power quality can be improved, which is crucial for the compatibility of sensitive loads and power grids.

[0065] In some of the embodiments, the step of adjusting the carrier signal to be controlled according to the error value and the error value threshold includes: if the error value is greater than the upper limit of the error value threshold, controlling to reduce the carrier period of the carrier signal to be controlled; if the error value is less than the lower limit of the error value threshold, controlling to increase the carrier period of the carrier signal to be controlled; until the error value is between the error value thresholds.

[0066] like Figure 2 As shown, if the error value is greater than the upper limit of the error value threshold, the carrier period of the carrier signal to be controlled can be controlled to be reduced (shortened); if the error value is less than the lower limit of the error value threshold, the carrier period of the carrier signal to be controlled can be controlled to be increased (extended), so that the final phase difference between the carrier signal to be controlled and the reference carrier signal meets the preset phase difference, and the following is obtained: Figure 3 The carrier shown meets the phase difference interleaving requirements.

[0067] The embodiment of the present invention adopts dynamic detection of carrier phase difference and then performs dynamic adjustment to realize staggered parallel control of carrier. The TBPRD (Time Base Period Register) in the EPWM module directly determines the carrier period. When there are slight differences in the TBPRD values ​​of multi-loop carriers, the TBCTR (TimeBase Counter) errors of the carriers between the loops will gradually accumulate. The effect brought by this error value is essentially similar to the effect of the staggered parallel carrier phase difference. Therefore, the carrier phase difference can be gradually approached to the standard value by increasing or decreasing the carrier period within a certain range. When the phase difference is too large, the adjustment speed is accelerated by reducing the carrier period to reduce the phase angle; when the phase difference is too small, the adjustment speed is slowed down by increasing the carrier period to widen the phase angle until the phase difference of the two carriers meets the requirements, and the carrier period restores the reference value, and finally outputs a multi-channel carrier that meets the staggered phase angle requirements.

[0068] The above provides a specific implementation method for carrier modulation of the carrier signal to be controlled based on the error value and the error value threshold. This control method can ensure that the phase difference between the carrier signal to be controlled and the reference carrier signal is maintained within the preset error value threshold, thereby achieving accurate phase matching. When the system operating conditions change and cause the carrier phase difference to deviate from the preset value, the control strategy can respond quickly, correct the phase difference by adjusting the carrier period, maintain system stability, and thus reduce power loss caused by phase mismatch, and improve the efficiency of DC / DC converters and DC / AC converters.

[0069] In some of the embodiments, the step of adjusting the controlled carrier signal according to the error value and the error value threshold includes: determining the target carrier cycle adjustment coefficient according to the error value and the relationship curve, and determining the carrier cycle adjustment value according to the carrier cycle adjustment threshold and the target carrier cycle adjustment coefficient; wherein the relationship curve includes a mapping relationship between the error value and the carrier cycle adjustment coefficient; and adjusting the controlled carrier signal according to the carrier cycle adjustment value.

[0070] The above provides another specific implementation method for carrier modulation of the controlled carrier signal based on the error value and the error value threshold. Compared with the dynamic adjustment method of directly increasing or decreasing the carrier period, the method provided by this specific implementation method can more accurately calculate the carrier period adjustment value, thereby significantly improving the carrier modulation efficiency.

[0071] Since the carrier period should not fluctuate too much, otherwise it is easy to cause pipe explosion problems, the maximum value of the carrier period adjustment (that is, the above-mentioned carrier period adjustment threshold) and the adjustment rate (carrier period adjustment coefficient) can be comprehensively considered to determine the carrier period adjustment value.

[0072] According to an embodiment of the present invention, the carrier period adjustment value ΔP is expressed as:

[0073] ΔP=k*ΔP max

[0074] Where k represents the carrier period adjustment coefficient, such as Figure 4 The mapping relationship curve between the carrier period adjustment coefficient and the error value is shown. It can be understood that the relationship curve can be designed according to the actual project requirements and is not limited to Figure 4 The form shown; ΔP max Indicates the carrier period adjustment threshold.

[0075] According to a specific implementation of an embodiment of the present invention, a relationship curve between the corresponding error value and the carrier cycle adjustment coefficient can be designed according to actual project requirements, thereby obtaining a carrier cycle adjustment coefficient that is more in line with the actual project requirements, so as to further improve the accuracy of the determined carrier cycle adjustment value.

[0076] In some of the embodiments, after the step of determining the carrier period adjustment value, the method further includes: obtaining the cumulative value of the carrier period frequency jittering step, and updating the carrier period of the controlled carrier signal according to the cumulative value of the carrier period frequency jittering step and the carrier period adjustment value.

[0077] Frequency jittering technology can disperse the spectrum of electromagnetic radiation by slightly changing the carrier frequency, thereby reducing peak electromagnetic radiation, improving the electromagnetic compatibility of the system, and reducing interference to surrounding electronic equipment. Considering that both frequency jittering and interleaved parallel connection are operations on the carrier, the two can be integrated into a carrier modulation function module. At the same time, since the synchronization function of the chip is not used, the phase adjustment value of the original frequency jittering algorithm does not need to be updated, and it can be autonomously controlled by the carrier interleaved parallel connection algorithm. Through the above settings, the output of the carrier interleaved parallel control module is set to the carrier period adjustment value, and the output of the frequency jittering algorithm is set to the cumulative value of the carrier period frequency jittering step length, which can realize the integration of adaptive adjustment of the carrier period and frequency jittering control, and further improve the accuracy of the carrier period corresponding to the carrier signal to be controlled.

[0078] In some of the embodiments, the method further includes: configuring at least one external interface to receive a carrier modulation requirement based on the external interface, and performing carrier modulation on the integrated optical storage system according to the carrier modulation requirement.

[0079] The design and implementation of the external interface is the key to the flexibility of the carrier modulation functional module. Specifically, necessary GPIO (general purpose input and output) pins can be reserved on the DSP to receive external signals, such as enable signals, limit signals, etc.

[0080] According to a specific implementation of an embodiment of the present invention, multiple external interfaces can be configured: Enable bit interface (carrier synchronization control / frequency jitter control): This interface allows the user to enable or disable the carrier interleaving parallel control and frequency jittering functions, so as to select the most suitable control mode according to actual needs. Limit interface: Provides upper and lower limits for carrier period adjustment and boundary conditions for carrier interleaving control errors to ensure that control is within a safe range and avoid over-adjustment. Step value interface: Defines the minimum unit of frequency jitter change, which is used to fine-tune the carrier period to optimize EMC (electromagnetic compatibility). Carrier address pointer interface: Allows users to access different carrier information through indexes, including reference carriers and carriers to be controlled, to achieve independent control of multi-loop converters. Carrier phase preset difference interface: Sets a preset difference (standard value) for adjusting the carrier phase to ensure that the phase relationship between each converter meets the requirements of interleaving parallel connection. Adaptive adjustment coefficient relationship curve: Provides a configurable curve to dynamically adjust the sensitivity of carrier modulation according to the system status to achieve more precise control.

[0081] The above-mentioned carrier modulation method provided by the embodiment of the present invention adopts the method of separately acquiring the carrier signals of multiple DC / DC converters in the integrated optical storage system, taking one of them as the reference carrier signal and the rest as the carrier signals to be controlled, calculating the carrier phase difference between the carrier signal to be controlled and the reference carrier signal; calculating the error value between the carrier phase difference and the preset carrier phase difference, and adjusting the carrier signal to be controlled according to the error value and the error value threshold, so as to realize the technical means of carrier modulation of the DC / DC converter, overcoming the problem that the counter is prone to mutation due to directly loading the new TBPHS value at the synchronization moment by configuring the synchronization function of the chip in the related art, thereby affecting the switching state of the switch in the converter, and sometimes even causing the problem of direct conduction of the switch circuit, and the problem of poor carrier modulation effect, realizing the real-time detection of the carrier phase difference between the carrier signal to be controlled and the reference carrier signal without using an additionally configured chip, and adaptively adjusting the carrier signal to be controlled based on the detection result and the preset carrier phase difference, avoiding the direct conduction risk of the switch circuit caused by the chip synchronization function, achieving the technical effect of improving the carrier modulation effect, realizing the automatic control of the carrier interleaved parallel connection and the adaptive adjustment of the carrier modulation, and expanding the applicable scenarios of the carrier modulation.

[0082] The embodiment of the present invention also provides a photovoltaic storage integrated system, such as Figure 4As shown, the photovoltaic-storage integrated system includes a multi-channel photovoltaic power management circuit, a multi-channel energy storage battery management circuit, a DC / AC converter, and the above-mentioned digital signal processing device; wherein the photovoltaic power management circuit includes photovoltaic components and DC / DC converters connected in series; the energy storage battery management circuit includes energy storage batteries and DC / DC converters connected in series; after the multi-channel photovoltaic power management circuit and the multi-channel energy storage battery management circuit are connected to the DC bus in parallel, they are connected to the AC power grid via the DC / AC converter; the digital signal processing device is connected to the control port of the DC / DC converter to execute any of the above-mentioned carrier modulation methods.

[0083] Since the DC / DC converters in the photovoltaic power management circuit and the DC / DC converters in the energy storage battery management system in the above-mentioned integrated photovoltaic and energy storage system are staggered and connected in parallel to the DC bus, in this configuration, the photovoltaic components and energy storage batteries first adjust the voltage and current to a level suitable for the DC bus through the DC / DC converters; these adjusted DC powers are combined on a shared DC bus, and then converted into AC power through a centralized DC / AC inverter, and finally sent to the grid. This design can reduce the number of inverters, reduce the overall cost and complexity of the system, but has higher requirements for the efficiency and stability of the DC / DC converter.

[0084] At the same time, the above-mentioned digital signal processing device is used to overcome the problem in the related technology that the new TBPHS value is directly loaded at the synchronization moment by configuring the synchronization function of the chip, which causes the counter to be prone to mutation, thereby affecting the switching state of the switch in the converter, and sometimes even causing the switch circuit to be directly connected, and the carrier modulation effect is poor. It realizes real-time detection of the carrier phase difference between the carrier signal to be controlled and the reference carrier signal without using an additionally configured chip, and adaptively adjusts the carrier signal to be controlled based on the detection result and the preset difference between the carrier phase, avoiding the direct connection risk of the switch circuit caused by the chip synchronization function, achieving the technical effect of improving the carrier modulation effect, realizing the automatic control of the carrier interleaving and parallel connection and the adaptive adjustment of the carrier modulation, and expanding the applicable scenarios of the carrier modulation.

[0085] In some of the embodiments, the digital signal processing device further includes a frequency jittering control module, which is used to obtain a cumulative value of a carrier period frequency jittering step length, and update a carrier period of a carrier signal to be controlled according to the cumulative value of the carrier period frequency jittering step length.

[0086] Frequency jittering technology can disperse the spectrum of electromagnetic radiation by slightly changing the carrier frequency, thereby reducing peak electromagnetic radiation, improving the electromagnetic compatibility of the system, and reducing interference to surrounding electronic equipment. Considering that both frequency jittering and interleaved parallel connection are operations on the carrier, the two can be integrated into a carrier modulation function module. At the same time, since the synchronization function of the chip is not used, the phase adjustment value of the original frequency jittering algorithm does not need to be updated, and it can be autonomously controlled by the carrier interleaved parallel connection algorithm. Through the above settings, the output of the carrier interleaved parallel control module is set to the carrier period adjustment value, and the output of the frequency jittering algorithm is set to the cumulative value of the carrier period frequency jittering step length, which can realize the integration of adaptive adjustment of the carrier period and frequency jittering control, and further improve the accuracy of the carrier period corresponding to the carrier signal to be controlled.

[0087] In some of the embodiments, the digital signal processing device further includes a plurality of external interfaces. The digital signal processing device receives carrier modulation requirements based on the external interfaces, and performs carrier modulation on the integrated optical storage system according to the carrier modulation requirements.

[0088] According to a specific implementation of an embodiment of the present invention, multiple external interfaces can be configured: Enable bit interface (carrier synchronization control / frequency jitter control): This interface allows the user to enable or disable the carrier interleaving parallel control and frequency jittering functions, so as to select the most suitable control mode according to actual needs. Limit interface: Provides upper and lower limits for carrier period adjustment and boundary conditions for carrier interleaving control errors to ensure that control is within a safe range and avoid over-adjustment. Step value interface: Defines the minimum unit of frequency jitter change, which is used to fine-tune the carrier period to optimize EMC (electromagnetic compatibility). Carrier address pointer interface: Allows users to access different carrier information through indexes, including reference carriers and carriers to be controlled, to achieve independent control of multi-loop converters. Carrier phase preset difference interface: Sets a preset difference (standard value) for adjusting the carrier phase to ensure that the phase relationship between each converter meets the requirements of interleaving parallel connection. Adaptive adjustment coefficient relationship curve: Provides a configurable curve to dynamically adjust the sensitivity of carrier modulation according to the system status to achieve more precise control.

[0089] It should be noted that the term "including" and its variations used in the embodiments of the present invention are open inclusions, that is, "including but not limited to". The term "based on" means "based at least in part on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one other embodiment"; the term "some embodiments" means "at least some embodiments". The modifications of "one" and "multiple" mentioned in the embodiments of the present invention are illustrative rather than restrictive. Those skilled in the art should understand that unless the context clearly indicates otherwise, it should be understood as "one or more".

[0090] The various steps described in the method implementation methods provided in the embodiments of the present invention may be performed in different orders and / or in parallel. In addition, the method implementation methods may include additional steps and / or omit the steps shown. The scope of protection of the present invention is not limited in this respect.

[0091] The term "embodiment" in this specification refers to specific features, structures or characteristics described in conjunction with the embodiment that can be included in at least one embodiment of the present invention. The appearance of this phrase in various places in the specification does not necessarily mean the same embodiment, nor does it mean that it is mutually exclusive with other embodiments and is independent or optional. The various embodiments in this specification are described in a related manner, and the same or similar parts between the various embodiments refer to each other. In particular, for the device, equipment, and system embodiments, since they are basically similar to the method embodiments, the description is relatively simple, and the relevant parts refer to the partial description of the method embodiment.

[0092] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of protection. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the attached claims.

Claims

1. A carrier modulation method, characterized in that: include: Respectively obtain carrier signals of multiple DC / DC converters in the integrated photovoltaic and energy storage system, take one of them as a reference carrier signal, and the rest as carrier signals to be controlled, and calculate the carrier phase difference between the carrier signal to be controlled and the reference carrier signal; An error value between the carrier phase difference value and a preset carrier phase difference value is calculated, and the carrier signal to be controlled is adjusted according to the error value and an error value threshold value to achieve carrier modulation of the DC / DC converter.

2. The method according to claim 1, characterized in that The photovoltaic-storage integrated system includes a multi-channel photovoltaic power management circuit and a multi-channel energy storage battery management circuit, wherein the photovoltaic power management circuit includes photovoltaic modules and DC / DC converters connected in series, and the energy storage battery management circuit includes energy storage batteries and DC / DC converters connected in series; the method further includes: For the multi-channel photovoltaic power management circuit, a first carrier phase difference value and a first error value are calculated respectively, and the first carrier signal to be controlled is adjusted according to the first error value and the first error value threshold; wherein the first carrier phase difference value refers to the carrier phase difference value between the first carrier signal to be controlled and the first reference carrier signal in the multi-channel photovoltaic power management circuit; For the multi-channel energy storage battery management circuit, the second carrier phase difference and the second error value are calculated respectively, and the second carrier signal to be controlled is adjusted according to the second error value and the second error value threshold; wherein the second carrier phase difference refers to the carrier phase difference between the second carrier signal to be controlled and the second reference carrier signal in the multi-channel energy storage battery management circuit.

3. The method according to claim 1, characterized in that: The step of adjusting the carrier signal to be controlled according to the error value and the error value threshold comprises: Determine a target carrier cycle adjustment coefficient according to the error value and the relationship curve, and determine a carrier cycle adjustment value according to the carrier cycle adjustment threshold and the target carrier cycle adjustment coefficient; wherein the relationship curve includes a mapping relationship between the error value and the carrier cycle adjustment coefficient; The carrier signal to be controlled is adjusted according to the carrier period adjustment value.

4. The method according to claim 3, characterized in that: After the step of determining the carrier period adjustment value, the method further includes: The carrier period frequency jitter step cumulative value is obtained, and the carrier period of the carrier signal to be controlled is updated according to the carrier period frequency jitter step cumulative value and the carrier period adjustment value.

5. The method according to claim 1, characterized in that The method further comprises the step of determining a preset carrier phase difference: Acquire the layout information of multiple photovoltaic power management circuits and multiple energy storage battery management circuits in the photovoltaic and energy storage integrated system; Determine, by a digital signal processing device, respectively, a first carrier phase preset difference between a first carrier signal to be controlled and a first reference carrier signal in multiple photovoltaic power management circuits based on the arrangement information; And determine a second carrier phase preset difference between a second carrier signal to be controlled and a second reference carrier signal in a multi-channel energy storage battery management circuit.

6. The method according to claim 1, characterized in that The step of calculating the carrier phase difference between the carrier signal to be controlled and the reference carrier signal comprises: Based on a time base counter in a digital signal processing device, a first time base count value and a second time base count value corresponding to the carrier signal to be controlled are respectively obtained, and the carrier phase difference value is calculated according to the first time base count value and the second time base count value.

7. The method according to claim 1, characterized in that The method further comprises: At least one external interface is configured to receive a carrier modulation requirement based on the external interface, and to perform carrier modulation on the integrated optical-storage system according to the carrier modulation requirement.

8. A photovoltaic storage integrated system, characterized in that: The system includes a multi-channel photovoltaic power management circuit, a multi-channel energy storage battery management circuit, a DC / AC converter, and a digital signal processing device; wherein, The photovoltaic power management circuit includes a photovoltaic module and a DC / DC converter connected in series; The energy storage battery management circuit includes an energy storage battery and a DC / DC converter connected in series; After the multiple photovoltaic power management circuits and the multiple energy storage battery management circuits are connected in parallel to the DC bus, they are connected to the AC power grid via the DC / AC converter; The digital signal processing device is connected to the control port of the DC / DC converter, and is used to execute the carrier modulation method described in any one of claims 1-7.

9. The system according to claim 8, characterized in that The digital signal processing device also includes a frequency jittering control module, which is used to obtain a carrier period frequency jittering step cumulative value, and update the carrier period of the carrier signal to be controlled according to the carrier period frequency jittering step cumulative value.

10. The system according to claim 8, characterized in that The digital signal processing device also includes a plurality of external interfaces. The digital signal processing device receives carrier modulation requirements based on the external interfaces, and performs carrier modulation on the integrated optical-storage system according to the carrier modulation requirements.

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