TWI721818B - Dc-dc conversion system and control method of dc-dc conversion system - Google Patents

Abstract

A control method of a DC-DC conversion system, comprising: detecting, by an output sensor, an output signal of the DC-DC conversion system; detecting, by multiple input voltage sensors, multiple input voltage signals of multiple series-connected first sides of at least one conversion unit of multiple conversion modules respectively; receiving, by a controller, the output signal and input voltage signals; generating, by the controller, a first control signal according to the output signal and an output reference signal; generating, by the controller, multiple input reference voltage signals according to the input voltage signals; performing voltage-equalization, by the controller, according to the input voltage signals and the input reference voltage signals to generate multiple second control signals; and outputting, by the controller, a corresponding modulation signal according to the first control signal and the corresponding second control signal to control multiple switches of the corresponding conversion unit.

Description

DC conversion system and DC conversion system control method

The present disclosure relates to a circuit and a control method, and more particularly to a DC conversion system and a DC conversion system control method.

In a DC conversion system, to ensure that the DC conversion system can work stably, it is necessary to balance the voltages of the power conversion modules in series and the currents in parallel.

If uneven pressure occurs, it will affect the selection of components and thermal design, and easily reduce system performance and operational reliability. Therefore, how to ensure pressure equalization is one of the important issues in this field.

One aspect of the present disclosure relates to a DC conversion system, which includes a plurality of power conversion modules, an output sensor, a plurality of input voltage sensors, and a controller. Any one of the power conversion modules includes at least one conversion unit. The conversion unit includes a first side and a second side. The first sides of the conversion units are connected in series with each other, and the second sides are connected in parallel with each other. The output sensor is used to measure the output signal of the DC conversion system. The plurality of input voltage sensors are used to measure the plurality of input voltage signals on the first side of the conversion unit, respectively. The controller is coupled to the conversion unit, the input voltage sensor and the output sensor to: receive the output signal and the input voltage signal; generate the first control signal according to the output signal and the output reference signal; generate a plurality of control signals according to the input voltage signal Input a reference voltage signal; perform voltage equalization control according to the input voltage signal and the input reference voltage signal to generate a plurality of second control signals; and output a corresponding modulation signal according to one of the first control signal and the second control signal to control the conversion unit The plural switches corresponding to one are actuated.

In some embodiments, the output signal is an output current signal, an output voltage signal, or an output power signal.

In some embodiments, the voltage levels of the input reference voltage signals are different.

In some embodiments, the controller includes a main controller and a plurality of local controllers, and the main controller is coupled to the output sensor and the local controllers for receiving the output signal and the inputs Voltage signal, and generate the first control signal according to the output signal and the output reference signal, and generate the input reference voltage signals according to the input voltage signals, the local controllers are respectively coupled to the power conversion modules The corresponding one, the main controller and the corresponding one of the input voltage sensors, each of the local controllers is used to: receive the first control signal; receive the corresponding input voltage signal and the corresponding input reference voltage Signal, and perform voltage equalization control according to the corresponding input voltage signal and the corresponding input reference voltage signal to generate the corresponding second control signal; and output the corresponding corresponding second control signal according to the first control signal and the corresponding second control signal The modulated signal is used to control the corresponding switches of the conversion unit to actuate.

In some embodiments, the main controller includes an error unit and a voltage stabilization control unit. The error unit receives the output signal and subtracts the output signal from the output reference signal to obtain an output error value. The voltage control unit receives and generates the first control signal according to the output error value.

In some embodiments, the controller includes a main controller and a plurality of local controllers, and the main controller is coupled to the output sensor and the local controllers for receiving the output signal and the inputs Voltage signal, and generate an output error value according to the output signal and the output reference signal, and generate the input reference voltage signals according to the input voltage signals, and the local controllers are each coupled to the power conversion modules. One, the main controller and the corresponding one of the input voltage sensors, each of the local controllers is used to: receive the first control signal; receive the corresponding input voltage signal and the corresponding input reference voltage signal , And perform voltage equalization control according to the corresponding input voltage signal and the corresponding input reference voltage signal to generate the corresponding second control signal; and according to the first control signal and the corresponding second control signal to output the corresponding The modulation signal controls the corresponding switches of the conversion unit to actuate.

In some embodiments, the main controller includes an error unit, and each of the local controllers includes a voltage stabilization control unit. The error unit receives the output signal and subtracts the output signal from the output reference signal to obtain the The error value is output, and the output error value is output to the voltage stabilization control units, and the voltage stabilization control units respectively receive and generate the first control signal according to the output error value.

In some embodiments, the controller includes a plurality of local controllers, each of the local controllers is coupled to a corresponding one of the power conversion modules, and the input voltage corresponding to a corresponding one of the power conversion modules The sensor and the output sensor, each of the local controllers is used to receive the output signal and the corresponding input voltage signal, wherein one of the local controllers is also used to receive the local controllers The input voltage signals output by the others, and the input reference voltage signals are generated according to the input voltage signals, and the first control signal is generated according to the output signal and the output reference signal, and the local controllers are each used for Perform voltage equalization control according to the corresponding input voltage signal and the corresponding input reference voltage signal to generate the corresponding second control signal, and output the corresponding modulation according to the first control signal and the corresponding second control signal The signal is used to control the corresponding switches of the conversion unit to actuate.

In some embodiments, the one of the local controllers includes an error unit and a voltage stabilization control unit. The error unit receives the output signal and subtracts the output signal from the output reference signal to obtain an output error Value, the voltage stabilization control unit receives and generates the first control signal according to the output error value.

In some embodiments, the controller includes a plurality of local controllers, each of the local controllers is coupled to a corresponding one of the power conversion modules, and the input voltage corresponding to a corresponding one of the power conversion modules The sensor and the output sensor, each of the local controllers is used to receive the output signal and the corresponding input voltage signal, wherein one of the local controllers is also used to receive the local controllers The input voltage signals output by others, the input reference voltage signals are generated according to the input voltage signals, and an output error value is generated according to the output signal and the output reference signal, and the local controllers are each used according to The output error value generates the first control signal, each of the local controllers performs voltage equalization control according to the corresponding input voltage signal and the corresponding input reference voltage signal to generate the corresponding second control signal, and according to the first control signal A control signal and the corresponding second control signal are used to output the corresponding modulation signal to control the corresponding switches of the conversion unit to act.

In some embodiments, the one of the local controllers includes an error unit, and each of the local controllers includes a voltage stabilization control unit. The error unit receives the output signal, and the output signal and the output reference signal The output error value is subtracted to obtain the output error value, and the output error value is respectively output to the corresponding voltage stabilization control units, and the voltage stabilization control units respectively receive and generate the first control signal according to the output error value.

In some embodiments, the controller includes a plurality of local controllers, each of the local controllers is coupled to a corresponding one of the power conversion modules, and the input voltage corresponding to a corresponding one of the power conversion modules The sensor and the output sensor, each of the local controllers is used to receive the output signal and the corresponding input voltage signal, each of the local controllers includes an error unit and a voltage stabilization control unit, the error unit Receive the output signal, subtract the output signal and the output reference signal to obtain an output error value, and output the output error value to the corresponding voltage stabilization control units, and the voltage stabilization control units respectively receive and combine The first control signal is generated according to the output error value; wherein, one of the local controllers is also used to receive the input voltage signals output by the other of the local controllers, and according to the input voltage signals Generate the input reference voltage signals, the local controllers each perform voltage equalization control according to the corresponding input voltage signal and the corresponding input reference voltage signal to generate the corresponding second control signal, and according to the first control signal And the corresponding second control signal to output the corresponding modulation signal to control the corresponding switches of the conversion unit to act.

In some embodiments, each of the at least one conversion unit includes a DC conversion module, and the DC conversion module includes a full-bridge inverter circuit, a resonant circuit, a transformer, and a rectifier circuit, wherein the resonant circuit is coupled Connected between an AC side of the full-bridge inverter circuit and a primary winding of the transformer, a secondary winding of the transformer is connected to an input side of the rectifier circuit, and the DC side of the full-bridge inverter circuit is A first side of the DC conversion module and an output side of the rectifier circuit are a second side of the DC conversion module.

In some embodiments, any one of the power conversion modules includes a first side and a second side, the first sides of the power conversion modules are connected in series with each other, and the power conversion modules The second sides of are connected in series with each other.

In some embodiments, the controller is further used to control a first gain crossover frequency of the first control signal to be greater than a second gain crossover frequency of the second control signals.

Another aspect of the present disclosure relates to a DC conversion system control method, including: measuring the output signal of the DC conversion system by an output sensor; and measuring a plurality of power conversion modules by a plurality of input voltage sensors respectively A plurality of input voltage signals on the first side of at least one conversion unit connected in series with each other; the controller receives the output signal and some input voltage signals; the controller generates the first control signal according to the output signal and the output reference signal; The controller generates a plurality of input reference voltage signals according to the input voltage signal; the controller performs voltage equalization control according to the input voltage signal and the input reference voltage signal to generate a plurality of second control signals; the controller generates a plurality of second control signals according to the first control signal and the second control signal The signal responder outputs the corresponding modulation signal to control the multiple switches of the corresponding switch unit to actuate.

In some embodiments, it further includes: subtracting the output signal from the output reference signal by a main controller of the controller to obtain an output error value, wherein the first control signal is obtained according to the output error value; The plurality of local controllers of the controller subtract the input voltage signal and the input reference voltage signal received respectively to obtain a voltage error value; and the local controllers in the controller calculate the respective voltage The error value is subjected to voltage equalization control to respectively generate the corresponding second control signal.

In some embodiments, it further includes: receiving the output signal by an error unit of the main controller; subtracting the output signal from the output reference signal by the error unit to obtain the output error value; and controlling by the main controller A voltage stabilization control unit of the generator receives and generates the first control signal according to the output error value.

In some embodiments, it further includes: subtracting the output signal from the output reference signal by the main controller of the controller to obtain an output error value; and multiple local controllers of the controller according to the output error value Generate the first control signal, and subtract the corresponding input voltage signal and the corresponding input reference voltage signal respectively to obtain a corresponding voltage error value; and the local controllers will each corresponding to the voltage The error value is subjected to voltage equalization control to respectively generate the corresponding second control signal.

In some embodiments, the voltage levels of the input reference voltage signals are different.

In some embodiments, it further includes: subtracting the output signal from the output reference signal by one of the plurality of local controllers of the controller to obtain an output error value, wherein the first control signal is based on the output The corresponding input voltage signal and the corresponding input reference voltage signal are subtracted by a plurality of local controllers of the controller to obtain a corresponding voltage error value; and by the local controllers Performing voltage equalization control on the respective corresponding voltage error values to respectively generate the corresponding second control signals.

In some embodiments, it further includes: subtracting the output signal from the output reference signal by one of the plurality of local controllers of the controller to obtain an output error value; The first control signal is generated according to the output error value, and the corresponding input voltage signal received by each and the corresponding input reference voltage signal are respectively subtracted to obtain a corresponding voltage error value; The local controller performs voltage equalization control on the respective corresponding voltage error values to respectively generate the corresponding second control signals.

In some embodiments, it further includes: when one of the voltage error values is greater than a first threshold or less than a second threshold, the controller performs voltage equalization control to adjust the corresponding second control signal; And when one of the voltage error values is not greater than the first threshold and not less than the second threshold, the controller maintains the corresponding second control signal.

In some embodiments, the second threshold is different from the first threshold.

In some embodiments, it further includes: the controller adds the first control signal and the second control signals to respectively generate and output the modulation signals.

In some embodiments, the method further includes: obtaining the input voltage signals synchronously by a plurality of local controllers in the controller according to a timing flag of a main controller in the controller.

In some embodiments, the method further includes: the controller controls the first gain crossover frequency of the first control signal to be greater than the second gain crossover frequency of the second control signals.

Another aspect of the present disclosure relates to a decoupling method. The decoupling method is suitable for the total output signal control loop and the voltage equalization control loop of the DC conversion system. The total output signal control loop is used to generate the first control signal. The voltage equalization control loop is used to generate a plurality of second control signals. The decoupling method includes: detecting the second control signals by the controller; judging by the controller whether all the second control signals are out of the coupling tolerance range; and when the second control signals are all out of the coupling tolerance range, the controller compensates the first The control signal and the second control signal, wherein the compensation direction of the controller for the first control signal is opposite to the compensation direction for the second control signal.

In some embodiments, it further includes: determining by the controller whether the second control signals are all greater than a coupling tolerance upper limit value or are all less than a coupling tolerance lower limit value; when the second control signals are all greater than the coupling tolerance Tolerance upper limit, the controller subtracts a compensation value from the second control signals, and adds the compensation value to the first control signal; and when the second control signals are less than the coupling tolerance lower For the limit value, the controller adds the compensation value to the second control signals, and subtracts the compensation value from the first control signal.

In some embodiments, the total output signal control loop may be a total output voltage control loop, a total output current control loop, or a total output power control loop.

In some embodiments, the first control signal and the second control signal are both switching frequency, counter value, or duty cycle value.

In some embodiments, the first control signal is one of the switching frequency, the counter value, and the duty cycle value, and the second control signal is the other one of the switching frequency, the counter value, and the duty cycle value.

To sum up, in this case, according to the input voltage signal and output signal transmitted by each power conversion module, the controller can generate a feedback signal through calculation and voltage equalization control, etc., by applying the above-mentioned various embodiments, so that each power supply The input voltage of the conversion module is balanced to reduce the voltage stress of the switch. Under the condition of not increasing the hardware voltage equalization circuit, the problem of voltage unevenness is solved by the control method, and the effect of reducing the cost is achieved.

The following is a detailed description of the embodiments in conjunction with the accompanying drawings to better understand the aspect of the case, but the provided embodiments are not intended to limit the scope covered by the disclosure, and the description of the structural operations is not intended to limit The order of execution, any recombination of components, and a device with an equal effect are all within the scope of this disclosure. In addition, according to industry standards and common practices, the drawings are only for the purpose of supplementary explanation, and are not drawn in accordance with the original dimensions. In fact, the dimensions of various features can be arbitrarily increased or decreased for ease of explanation. In the following description, the same elements will be described with the same symbols to facilitate understanding.

Unless otherwise specified, the terms used in the entire specification and the scope of the patent application usually have the usual meaning of each term used in this field, in the content disclosed here, and in the special content. Some terms used to describe the present disclosure will be discussed below or elsewhere in this specification to provide those skilled in the art with additional guidance on the description of the present disclosure.

In addition, the terms "include", "include", "have", "contain", etc. used in this article are all open terms, meaning "including but not limited to". In addition, the "and/or" used in this article includes any one of one or more of the related listed items and all combinations thereof.

In this text, when an element is referred to as "connection" or "coupling", it can refer to "electrical connection" or "electrical coupling". "Connected" or "coupled" can also be used to indicate that two or more components cooperate or interact with each other. In addition, although terms such as “first”, “second”, etc. are used herein to describe different elements, the terms are only used to distinguish elements or operations described in the same technical terms. Unless the context clearly indicates, the terms do not specifically refer to or imply order or sequence, nor are they used to limit the present invention.

Please refer to Figure 1. FIG. 1 is a schematic diagram of a DC conversion system 100 according to some embodiments of the present application. As shown in Figure 1, the DC conversion system 100 adopts a DC conversion circuit structure in which the first side is connected in series and the second side is connected in parallel. In some embodiments, the first side is the high-pressure side, wherein the high-pressure side may be the input side, the second side is the low-pressure side, and the low-pressure side may be the output side. In other embodiments, the high-voltage side may be the output side, and the low-voltage side may be the input side. For the convenience of description, the following content will be described with an input-series-output-parallel (Input-Series-Output-Parallel, ISOP) embodiment, but this case is not limited to this.

The DC conversion system 100 includes a plurality of (n) power conversion modules MOD1 to MODn, an output sensor 120, a plurality (n) of input voltage sensors 140_1 to 140_n, a controller CON, and a load LOAD. Among them, n is a positive integer greater than or equal to 1. Any one of the power conversion modules MOD1 to MODn includes at least one conversion unit DC1 to DCn. The conversion units DC1 to DCn each include a first side and a second side. In some embodiments, the power conversion module includes a conversion unit. In some other embodiments, the power conversion module includes more than two conversion units.

Structurally, as shown in Fig. 1, the plurality of first sides of the conversion units DC1 to DCn are connected in series with each other. The plurality of second sides of the conversion units DC1 to DCn are connected in parallel to each other. The input voltage sensors 140_1 to 140_n are each coupled to the first side of the corresponding conversion unit DC1 to DCn. The output sensor 120 is coupled to the second side of the conversion units DC1 to DCn, that is, the output side of the DC conversion system. The controller CON is coupled to the input voltage sensors 140_1 to 140_n, the output sensor 120 and the conversion units DC1 to DCn. The load LOAD is coupled between the positive and negative cross voltages on the second side of the conversion units DC1 ˜DCn.

Specifically, the first side where the conversion units DC1 to DCn are connected in series is the high voltage side V1, and the second side where the conversion units DC1 to DCn are connected in parallel is the low voltage side V2. Each conversion unit includes a capacitor, and the capacitor is connected in parallel to the first side of the conversion unit. For example, the conversion unit DC1 includes a capacitor Ci1, and the capacitor Ci1 is connected in parallel to the first side of the conversion unit DC1, and the conversion unit DCn includes a capacitor Cin, And the capacitor Cin is connected in parallel to the first side of the conversion unit DCn. The input voltage sensors 140_1 to 140_n are respectively coupled to both ends of the capacitors Ci1 to Cin (for example, the input voltage sensor 140_1 is coupled to both ends of the capacitor Ci1). In addition, the output capacitor Co is coupled between the positive and negative cross-voltages on the output side of the DC conversion system, that is, between the positive and negative cross-voltages on the second side of the conversion units DC1 to DCn. In some embodiments, the output sensor 120 may be coupled to both ends of the output capacitor Co to measure the output voltage V2 (as shown in FIG. 1). In some other embodiments, the output sensor 120 can be coupled to any end of the output side of the DC conversion system for measuring the output current (as shown in FIG. 3). In some other embodiments, the output sensor 120 is coupled to any end of the output side of the DC conversion system and to both ends of the output capacitor Co for measuring the output power.

In operation, as shown in FIG. 1, the output sensor 120 is used to measure the output signal Sout of the DC conversion system 100. The output signal Sout can be an output current signal, an output voltage signal, or an output power signal. The input voltage sensors 140_1 to 140_n are used to measure a plurality of input voltage signals Vi1 to Vin on the first side of the conversion units DC1 to DCn, respectively. The controller CON is used to receive the output signal Sout and the input voltage signals Vi1 to Vin, and to generate the modulation signals M1 to Mn to the corresponding conversion units DC1 to DCn. The multiple switches of the conversion units DC1 to DCn are actuated according to the corresponding modulation signals M1 to Mn.

In this way, by the conversion unit DC1～DCn in each power conversion module MOD1～MODn transmitting their respective input voltage signals Vi1～Vin to the controller CON, the controller CON can judge the current status based on the input voltage signals Vi1～Vin The number of conversion units DC1 to DCn in the power conversion modules MOD1 to MODn is calculated to generate modulation signals M1 to Mn that are fed back to the plurality of switches of the conversion units DC1 to DCn in the corresponding power conversion modules MOD1 to MODn.

In some embodiments, the controller CON can be implemented by various processing circuits, digital signal processors (DSP), complex programmable logic devices (CPLD), and field programmable gate arrays (Field-Programmable Logic Device). Various methods such as programmable gate array, FPGA) are implemented. In some embodiments, the modulation signal may be a frequency modulation signal (FM) or a pulse width modulation signal (pluse width modulation, PWM).

It is worth noting that the lowercase English indexes 1 to n in the component numbers and signal numbers used in the description and drawings of this case are only for the convenience of referring to individual components and signals, and are not intended to limit the number of the aforementioned components and signals to a specific number. . In the specification and drawings of this case, if a component number or signal number is used without indicating the index of the component number or signal number, it means that the component number or signal number refers to the component group or signal group to which it belongs. Any component or signal of. For example, the object referred to by the component number DC1 is the conversion unit DC1, and the object referred to by the component number DC is an unspecified arbitrary conversion unit among the conversion units DC1 to DCn. For another example, the object referred to by the element number 140_1 is the input voltage sensor 140_1, and the object referred to by the element number 140 is any unspecified input voltage sensor among the input voltage sensors 140_1 to 140_n. For another example, the signal number Vi1 refers to the input voltage signal Vi1, and the signal number Vi refers to any unspecified input voltage signal among the input voltage signals Vi1 to Vin.

Please refer to Figure 2A and Figure 2B. FIG. 2A and FIG. 2B are schematic diagrams illustrating a conversion unit DC according to some embodiments of the present disclosure. As shown in FIG. 2A, each conversion unit DC includes a DC conversion module, and the DC conversion module includes a full-bridge inverter circuit 132, a resonance circuit 134, a transformer 136, and a rectifier circuit 138. In some embodiments, the full-bridge inverter circuit 132 includes a plurality of switches, but the number and connection manner of the switches are not limited to this case.

Structurally, the input terminal of the full-bridge inverter circuit 132 is the first side of the conversion unit DC, and the capacitor Ci is connected in parallel to the input terminal of the full-bridge inverter circuit 132. The input terminal of the full-bridge inverter circuit 132 is used to receive the voltage Vi of the high-voltage side V1. The input voltage sensor 140 is coupled to both ends of the input capacitor Ci for measuring the voltage Vi on both sides of the capacitor Ci and outputting the measured voltage Vi to the controller CON. The output terminal of the full-bridge inverter circuit 132 is electrically coupled to the input terminal of the resonance circuit 134 for outputting the AC signal Sig converted by the full-bridge inverter circuit 132 by the DC voltage Vi to the resonance circuit 134. The output terminal of the resonance circuit 134 is electrically coupled to the primary side of the transformer 136. The input terminal of the rectifier circuit 138 is electrically coupled to the secondary side of the transformer 136. The output terminal of the rectifier circuit 138 is electrically coupled to the output capacitor Co to provide a DC output voltage to the load or other subsequent circuits. In other words, the resonance circuit 134 is coupled between the AC side of the full-bridge inverter circuit 132 and the primary winding Np of the transformer 136. The secondary winding Ns of the transformer 136 is connected to the input side of the rectifier circuit 138. The DC side of the full-bridge inverter circuit 132 is the first side of the DC conversion module, that is, the DC side of the full-bridge inverter circuit 132 is the first side of the conversion unit, and the output side of the rectifier circuit 138 is the first side of the DC conversion module. The second side, that is, the output side of the rectifier circuit 138, is the output side of the DC conversion system.

In some embodiments, as shown in FIG. 2A, the full-bridge inverter circuit 132 includes switches SW1 to SW4. The resonance circuit 134 includes a resonance capacitor Lc, a resonance inductance Lr, and an excitation inductance Lm. The primary side of the transformer 136 may include a set of primary windings Np, and the secondary side may include a set of secondary windings Ns. The rectifier circuit 138 may adopt a full-bridge rectifier circuit, including diodes Di1 to Di4.

Specifically, the first terminals of the switches SW1 and SW2 are electrically coupled to the positive terminal of the voltage Vi (that is, the positive terminal of the first side of the full-bridge inverter circuit 132), and the second terminals of the switches SW1 and SW2 are respectively It is electrically coupled to the resonance circuit 134. The first ends of the switches SW3 and SW4 are electrically coupled to the second ends of the switches SW1 and SW2, respectively, and the second ends of the switches SW3 and SW4 are electrically coupled to the negative end of the voltage Vi (that is, the full-bridge inverter circuit 132 on the first side of the negative terminal). The control ends of the switches SW1 to SW4 are respectively used to receive the modulation signal, so that the switches SW1 to SW4 are selectively turned on or off according to the modulation signal. Thereby, the full-bridge inverter circuit 132 can output the AC signal Sig by selectively turning on the switches SW1 to SW4.

The resonance capacitor Lc, the resonance inductance Lr, and the primary winding Np of the transformer 136 are connected in series with each other. The magnetizing inductance Lm and the primary winding Np of the transformer 136 are connected in parallel with each other. The anode end of the diode Di1 and the cathode end of the diode Di3 are electrically coupled to the first end of the secondary winding Ns. The anode end of the diode Di2 and the cathode end of the diode Di4 are electrically coupled to the second end of the secondary winding Ns. The cathode terminals of the diodes Di1 and Di2 are electrically coupled to the positive terminal of the output capacitor Co. The anode terminals of the diodes Di3 and Di4 are electrically coupled to the negative terminal of the output capacitor Co.

In other embodiments, as shown in Figure 2B, each power conversion module MOD includes two conversion units DCa, DCb, and each conversion unit DCa, DCb includes a DC conversion module: a full-bridge inverter circuit 132 , The resonant circuit 134, the transformer 136, and the rectifier circuit 138 (in the embodiment of FIG. 2B, only a total of two conversion units DCa and DCb are shown, but this case is not limited to this number). In the embodiment shown in FIG. 2B, components similar to those in the embodiment shown in FIG. 2A are denoted by the same component symbols, and the operations have been described in the previous paragraphs, and will not be repeated here. Compared with the embodiment shown in FIG. 2A, in this embodiment, the power conversion module MOD includes full-bridge inverter circuits 132a and 132b, resonance circuits 134a and 134b, transformers 136a and 136b, and rectifier circuits 138a and 138b. Structurally, the full-bridge inverter circuits 132a and 132b are connected in series with each other, and the rectifier circuits 138a and 138b are connected in parallel with each other. The capacitor Cia is connected in parallel to the first side of the full-bridge inverter circuit 132a. The input voltage sensor 140a is used to measure the voltage Via on both sides of the capacitor Cia. Similarly, the capacitor Cib is connected in parallel to the first side of the full-bridge inverter circuit 132b. The input voltage sensor 140b is used to measure the voltage Vib on both sides of the capacitor Cib.

It is worth noting that the implementation of the above circuit is not used to limit this case. For example, the resonant circuit 134 can also implement an LC resonant circuit, an LCC resonant circuit, and an LLC resonant circuit by one or more sets of inductance units and capacitor units. Therefore, the LLC resonant circuit depicted in the diagram in this case is only possible in this case. One of the implementation methods is not intended to limit the case. In other words, the resonant circuit, transformer, and rectifier circuit in each embodiment of the present case can be implemented in any form well known to those skilled in the art.

Please refer to Figure 3. FIG. 3 is a detailed schematic diagram of a DC conversion system 100 according to some embodiments of the present disclosure. In the embodiment shown in FIG. 3, components similar to those in the embodiment in FIG. 1 are denoted by the same component symbols, and the operations have been described in the previous paragraphs, and will not be repeated here. Compared with the embodiment shown in Fig. 1, in this embodiment, the controller CON1 includes a main controller MCU and a plurality of local controllers LCU1 to LCUn. For the convenience of description, only 3 local controllers are shown in Figure 3, but the number is not limited to this.

Structurally, the main controller MCU is coupled to the output sensor 120 and the local controllers LCU1-LCUn. The local controllers LCU1 to LCUn are respectively coupled to the corresponding power conversion modules MOD1 to MODn (for example, the local controller LCU1 is coupled to the power conversion module MOD1). The local controllers LCU1 to LCUn are respectively coupled to the corresponding input voltage sensors 140_1 to 140_n (for example, the local controller LCU1 is coupled to the input voltage sensor 140_1). The local controllers LCU1 to LCUn are coupled to the main controller MCU.

In operation, the local controllers LCU1 to LCUn are respectively used to receive the input voltage signals Vi1 to Vin from the corresponding input voltage sensors 140_1 to 140_n, and to output the input voltage signals Vi1 to Vin to the main controller MCU. The main controller MCU is used to receive the input voltage signals Vi1-Vin, and the output signal Sout from the output sensor 120. The main controller MCU generates the input reference voltage signals according to the received input voltage signals Vi1 to Vin. Then, the main controller MCU and the local controllers LCU1～LCUn are used to generate the first and second control signals according to the output signal Sout, the input voltage signals Vi1～Vin and the output reference signal, and output modulation according to the first and second control signals The signal is actuated by the switch in the control conversion unit. The detailed operation content will be described in subsequent paragraphs.

Please refer to Figure 4. FIG. 4 is a detailed schematic diagram of another DC conversion system 100 according to other embodiments of the present disclosure. In the embodiment shown in FIG. 4, similar components to those in the embodiment shown in FIG. 1 and FIG. 3 are denoted by the same component symbols, and the operations have been described in the previous paragraphs, and will not be repeated here. Compared with the embodiment shown in Fig. 3, in this embodiment, the controller CON2 includes a plurality of local controllers MAS, SLA1 to SLAn. For convenience of description, only 3 local controllers are shown in Figure 4, but the number is not limited to this.

Structurally, the local controllers MAS, SLA1-SLAn are electrically coupled to each other. Specifically, the multiple local controllers included in the controller CON2 have a master-slave architecture. Operationally, any one of the multiple local controllers will act as the master (Master) to perform the master control function, while the other local controllers will act as the slaves (Slave). In this way, the host can be switched freely according to actual conditions and requirements, and has better redundancy.

Specifically, after determining the host, the local controllers SLA1 to SLAn are used to receive the input voltage signals Vi2 to Vin from the corresponding input voltage sensors 140_2 to 140_n, and to output the input voltage signals Vi2 to Vin to the host computer. Local controller MAS. The local controller MAS is used for receiving the output signal Sout from the output sensor 120, receiving the input voltage signal Vi1 through the corresponding input voltage sensor 140_1, and receiving the input voltage signals Vi2~Vin from other local controllers SLA1~SLAn. Then, the local controllers MAS, SLA1 to SLAn are used to generate the first and second control signals according to the output signal Sout, the input voltage signals Vi1 to Vin and the output reference signal, and output the modulation signal according to the first and second control signals to control The switch in the conversion unit is activated. The detailed operation content will be described in subsequent paragraphs.

Because the hardware parameters in the power conversion modules MOD1～MODn may be inconsistent, the voltage on the input side may be uneven. Moreover, the wider the input or output voltage range, the more serious the uneven voltage problem may be. Therefore, to ensure the stable operation of the DC conversion system 100, it is necessary to ensure the voltage equalization and current equalization of the power conversion modules MOD1 to MODn.

Please refer to Figure 5. FIG. 5 is a schematic diagram of a controller CON according to some embodiments of the present disclosure. As shown in FIG. 5, the controller CON includes error units 162_1 to 162_n, voltage stabilization control units 164_1 to 164_n, superposition units 166_1 to 166_n, error unit 182, voltage stabilization control unit 184, and input reference voltage signal generator 186.

In some embodiments, the error unit 182 receives the output signal Sout, and subtracts the output signal Sout from the output reference signal Sref to obtain the output error value Serr. Then, the voltage stabilization control unit 184 receives the output error value Serr, and generates the first control signal CS1 according to the output error value Serr. On the other hand, the input reference voltage signal generator 186 generates corresponding input reference voltage signals Vf1 ˜Vfn according to the input voltage signals Vi1 ˜Vin. Then, the error units 162_1 to 162_n respectively receive the corresponding input voltage signals Vi1 to Vin and the corresponding input reference voltage signals Vf1 to Vfn, and phase the corresponding input voltage signals Vi1 to Vin and the corresponding input reference voltage signals Vf1 to Vfn. Subtract to obtain the corresponding voltage error value Vr1 ~ Vrn. Then, the voltage stabilization control units 164_1 to 164_n receive the corresponding voltage error values Vr1 to Vrn, and perform voltage equalization control according to the corresponding voltage error values Vr1 to Vrn to generate the corresponding second control signals CS2_1 to CS2_n. The detailed operation of the pressure equalization control will be described in the subsequent paragraphs.

After that, the superimposing units 166_1 to 166_n respectively receive the first control signal CS1 and the corresponding second control signals CS2_1 to CS2_n, and superimpose the first control signal CS1 and the corresponding second control signals CS2_1 to CS2_n to obtain the corresponding modulation signal M1～Mn. Then, the controller CON outputs the modulation signals M1 to Mn to the corresponding driving signal generators DSG1 to DSGn, respectively. The drive signal generators DSG1 to DSGn generate corresponding drive signals D1 to Dn according to the corresponding modulation signals M1 to Mn, and output the drive signals D1 to Dn to the corresponding conversion units DC1 to DCn of the full-bridge inverter circuit 132 Multiple switches. The multiple switches of the full-bridge inverter circuit 132 can be selectively turned on or off according to the corresponding driving signals D1 to Dn.

In this way, through the operation of the above-mentioned controller CON, the conversion units DC1 to DCn can be feedback controlled according to the output signal Sout and the input voltage signals Vi1 to Vin, so that the DC conversion system 100 achieves the effects of voltage equalization and voltage stabilization.

In addition, according to the deduction of the equivalent circuit model, it can be known that when the number of conversion units DC1 to DCn connected in series and parallel in the DC conversion system 100 is greater than two (ie, n>2), the total amount used to generate the first control signal CS1 The output signal control loop will not affect the voltage equalization control loop used to generate the second control signals CS2_1 to CS2_n, but the voltage equalization control loop will affect the total output signal control loop. In other words, due to the coupling of the voltage equalization control loop to the total output signal control loop, the operation of the total output signal control loop will be inhibited, and the voltage equalization capability of the voltage equalization control loop will decrease. Therefore, in order to avoid this problem, the speed of the total output signal control loop should be increased, and the speed of the voltage equalization control loop should be slowed down to reduce the adverse effects of coupling. Accordingly, in some embodiments, the controller CON will ensure that the response speed of the total output signal control loop is greater than the response speed of the voltage equalization control loop. For example, the controller CON controls the gain crossover frequency of the voltage equalization control loop to be less than half of the gain crossover frequency of the total output signal control loop.

In other embodiments, for the coupling of the voltage equalization control loop to the total output signal control loop, the controller CON will detect the second control signals CS2_1 to CS2_n output by the voltage equalization control loop. When the controller CON determines that the bias generated by the control coupling is too large, it will correct the voltage equalization control loop and the total output signal control loop to achieve decoupling. Please refer to Figure 14. FIG. 14 is a flowchart of a decoupling method 200 according to some embodiments of the present disclosure. As shown in FIG. 14, the decoupling method 200 includes operations S210, S220, and S230.

First, in operation S210, the coupling tolerance range of the second control signals CS2_1 to CS2_n is set. Specifically, the upper limit value and the lower limit value of the coupling tolerance are preset by the controller CON according to the second control signals CS2_1 to CS2_n.

Then, in operation S220, it is determined whether all the second control signals CS2_1 to CS2_n exceed the coupling tolerance range. Specifically, the controller CON continuously detects the second control signals CS2_1 to CS2_n, and determines whether all the second control signals CS2_1 to CS2_n are greater than the coupling tolerance upper limit, or all the second control signals CS2_1 to CS2_n are less than the coupling tolerance. Tolerate the lower limit.

When all the second control signals CS2_1 to CS2_n are out of the coupling tolerance range, operation S230 is performed to compensate the first control signal CS1 and the second control signals CS2_1 to CS2_n according to the offset direction. Specifically, when all the second control signals CS2_1 to CS2_n are greater than the upper limit of coupling tolerance, the controller CON subtracts a preset compensation value from all the second control signals CS2_1 to CS2_n, and the first control signal CS1 A preset compensation value is added accordingly. On the other hand, when all the second control signals CS2_1 to CS2_n are less than the lower limit of the coupling tolerance, the controller CON adds a preset compensation value to all the second control signals CS2_1 to CS2_n, and the first control signal CS1 A preset compensation value is subtracted accordingly. In other words, the compensation directions of the second control signals CS2_1 to CS2_n and the first control signal CS1 are opposite.

After the compensation is performed, operation S220 will be performed again. If all the second control signals CS2_1 to CS2_n still exceed the coupling tolerance range, compensation will be performed again until at least one of the second control signals CS2_1 to CS2_n is within the coupling tolerance range, then the compensation is stopped. In this way, by monitoring the second control signals CS2_1 to CS2_n by the decoupling method 200 and compensating according to the reverse direction of the offset direction, the problems of coupling and offset can be avoided.

In some embodiments, the aforementioned coupling tolerance range (ie, the upper limit of coupling tolerance and the lower limit of coupling tolerance) and the compensation value are all preset values, which can be based on the actual working condition of the DC conversion system 100 (eg, load size) Design and adjust. For example, when the load becomes larger, the tolerance range becomes wider and the compensation value becomes larger. When the load becomes smaller, the tolerance range becomes narrower and the compensation value becomes smaller.

It is worth noting that the above-mentioned total output signal control loop may include a total output voltage, total output current, or total output power control loop. In addition, the second control signal detected in the decoupling method 200 and its coupling tolerance range can all be the switching frequency, the counter value, the duty cycle value or other detected values. In other embodiments, the detected second control signal and its coupling tolerance range can be different types of values among the various types mentioned above, and after conversion based on the relationship between the two, the judgment condition and corresponding compensation are performed.

Please refer to Figure 6. FIG. 6 is a schematic diagram showing a main controller MCU and a plurality of local controllers LCU1 ˜LCUn according to some embodiments of the present disclosure. Specifically, FIG. 6 is a schematic diagram of the controller CON1 in FIG. 3 including a main controller MCU and a plurality of local controllers LCU1 to LCUn. In the embodiment shown in FIG. 6, elements similar to those in the embodiment shown in FIG. 5 are denoted by the same reference numerals. In this embodiment, the main controller MCU includes an error unit 182, a voltage stabilization control unit 184, and an input reference voltage signal generator 186. The main controller MCU subtracts the output signal Sout and the output reference signal Sref to obtain the output error value Serr, and the voltage stabilization control unit 184 receives and outputs the error value Serr to generate the first control signal CS1. The input reference voltage signal generator 186 in the main controller MCU generates corresponding input reference voltage signals Vf1 to Vfn according to the input voltage signals Vi1 to Vin. The local controllers LCU1 to LCUn each include corresponding error units 162_1 to 162_n, voltage stabilization control units 164_1 to 164_n, and superposition units 166_1 to 166_n (for example, the local controller LCU1 includes error unit 162_1, voltage stabilization control unit 164_1, and superposition unit 166_1). ). The detailed component operation has been explained in the previous paragraph, and will not be repeated here.

Please refer to Figure 7. FIG. 7 is a schematic diagram illustrating another main controller MCU and multiple local controllers LCU1 ˜LCUn according to some embodiments of the present disclosure. Specifically, FIG. 7 is a schematic diagram of the controller CON1 in FIG. 3 including a main controller MCU and a plurality of local controllers LCU1 to LCUn. In the embodiment shown in FIG. 7, elements similar to those in the embodiment shown in FIG. 5 are denoted by the same reference numerals. In this embodiment, the main controller MCU includes an error unit 182 and an input reference voltage signal generator 186. The main controller MCU subtracts the output signal Sout and the output reference signal Sref to obtain the output error value Serr. The input reference voltage signal generator 186 in the main controller MCU generates corresponding input reference voltage signals Vf1 to Vfn according to the input voltage signals Vi1 to Vin. The local controllers LCU1 ~ LCUn each include corresponding voltage stabilization control units 184_1 ~ 184_n, error units 162_1 ~ 162_n, voltage stabilization control units 164_1 ~ 164_n, and superposition units 166_1 ~ 166_n (for example, the local controller LCU1 includes a voltage stabilization control unit 184_1 , Error unit 162_1, voltage stabilization control unit 164_1, and superposition unit 166_1).

Furthermore, the error unit 182 in the main controller MCU outputs the output error value Serr obtained by subtracting the output signal Sout and the output reference signal Sref to the respective local controllers LCU1 ˜LCUn. The voltage stabilization control units 184_1 to 184_n in the respective local controllers LCU1 to LCUn receive the output error value Serr, and respectively generate the first control signal CS1 according to the output error value Serr. The detailed operations of other components have been explained in the previous paragraphs, and will not be repeated here.

Please refer to Figure 8. FIG. 8 is a schematic diagram showing a plurality of local controllers MAS, SLA1 ˜SLAn according to other embodiments of the present disclosure. Specifically, Fig. 8 is a schematic diagram of the controller CON2 in Fig. 4 including multiple local controllers MAS, SLA1 to SLAn. In the embodiment shown in FIG. 8, elements similar to those in the embodiment shown in FIG. 5 are denoted by the same reference numerals. In operation, any one of the multiple local controllers is used as the master to perform the master control, and the other local controllers are used as slaves to receive the control of the master. Therefore, in this embodiment, each local controller MAS , SLA1-SLAn each include an error unit 182, a voltage stabilization control unit 184, and an input reference voltage signal generator 186.

In operation, for example, the error units 182_1 to 182_n of the local controllers MAS and SLA1 to SLAn can receive and share the same output signal Sout and/or output reference signal Sref. The voltage stabilization control units 184_1~184_n of each local controller MAS, SLA1~SLAn can respectively receive the output error value Serr output by the corresponding error unit 182_1~182_n, or can be controlled by each voltage stabilization control unit 184_1~184_n from the error unit 182_1~ One of 182_n receives and shares the same output error value Serr. The input reference voltage signal generators 186_1 to 186_n of each local controller MAS, SLA1 to SLAn can respectively generate corresponding input reference voltage signals Vf1 to Vfn, or one of the input reference voltage signal generators 186_1 to 186_n can generate input The reference voltage signals Vf1～Vfn are sent to other local controllers. For further description, please refer to the different embodiments in Figure 9, Figure 10 and Figure 11. In order to make the description concise and clear, in the embodiments in Figures 9, 10, and 11, only the functional blocks in use are drawn in each local controller, and the unused components will not be drawn, which does not represent The local controller does not have this function or component.

Please refer to Figure 9. FIG. 9 is a schematic diagram showing a plurality of local controllers MAS, SLA1 ˜SLAn according to other embodiments of the present disclosure. In the embodiment shown in FIG. 9, the components similar to those in the embodiment shown in FIG. 8 are denoted by the same reference numerals. In this embodiment, the input reference voltage signal generator 186 in the local controller MAS serving as the host generates corresponding input reference voltage signals Vf1 to Vfn according to the input voltage signals Vi1 to Vin. The local controller MAS as the host receives and generates the first control signal CS1 according to the output signal and the output reference signal. Each local controller is used to perform voltage equalization control according to the corresponding input voltage signals Vi1 to Vin and the corresponding input reference voltage signals Vf1 to Vfn to generate the corresponding second control signal CS2. The detailed element operation is similar to that of the embodiment in FIG. 6, and has been described in the previous paragraph, so it will not be repeated.

Please refer to Figure 10. FIG. 10 is a schematic diagram showing another multiple local controllers MAS, SLA1 ˜SLAn according to other embodiments of the present disclosure. In the embodiment shown in FIG. 10, elements similar to those in the embodiment shown in FIG. 8 are denoted by the same reference numerals. In this embodiment, the input reference voltage signal generator 186 in the local controller MAS serving as the host generates corresponding input reference voltage signals Vf1 to Vfn according to the input voltage signals Vi1 to Vin. The error unit 182 in the local controller MAS as the host receives and generates an output error value Serr according to the output signal Sout and the output reference signal Sref. The voltage stabilization control units 184_1 to 184_n in each local controller receive and generate the first control signal CS1 according to the output error value Serr. The detailed component operation is similar to that of the embodiment in FIG. 7 and has been described in the previous paragraph, so it will not be repeated.

Please refer to Figure 11. FIG. 11 is a schematic diagram showing another multiple local controllers MAS, SLA1 ˜SLAn according to other embodiments of the present disclosure. In the embodiment shown in FIG. 11, elements similar to those in the embodiment shown in FIG. 8 are denoted by the same reference numerals. In this embodiment, the input reference voltage signal generator 186 of the local controller MAS as the host generates corresponding input reference voltage signals Vf1 to Vfn according to the input voltage signals Vi1 to Vin, and outputs the input reference voltage signals Vf1 to Vfn to Corresponding local controllers MAS, SLA1～SLAn. The local controller MAS as the master outputs the output signal Sout received from the output sensor 120 to the other local controllers SLA1 to SLAn as slaves. The error units 182_1 to 182_n in all the local controllers MAS and SLA1 to SLAn respectively subtract the output signal Sout and the output reference signal Sref to obtain the output error value Serr. Then, the voltage stabilization control units 184_1 to 184_n in all the local controllers MAS and SLA1 to SLAn respectively generate the first control signal CS1 according to the output error value Serr. The detailed operations of other components have been explained in the previous paragraphs, and will not be repeated here.

It is worth noting that the input reference voltage signals Vf1 to Vfn in FIGS. 5 to 11 above may be at the same voltage level or not at the same voltage level. For example, when the power conversion modules MOD1 to MODn are connected in series on the first side, there is a midpoint where the potential is zero, and the number of power conversion modules between the midpoint and the positive voltage is greater than the midpoint and the negative voltage. When the number of power conversion modules is different, through different input reference voltage signals Vf1 to Vfn, it can be ensured that the positive and negative voltages have the same voltage at the midpoint. For example: the positive voltage is +120V, the negative voltage is -120V, there are 3 power conversion modules MOD1～MOD3 between the positive voltage and the midpoint, and 4 power conversion modules MOD4～MOD7 between the negative voltage and the midpoint. Set the input reference voltage signals Vf1 to Vf3 to 40V, and set the input reference voltage signals Vf4 to Vf7 to 30V. In this way, it can be ensured that the positive and negative voltages have the same voltage at the midpoint.

In addition, for the detailed operation of the equalizing control, please refer to Figure 12A and Figure 12B. FIG. 12A and FIG. 12B are schematic diagrams illustrating a signal of a voltage equalization control according to some embodiments of the present disclosure. As shown in Figures 12A and 12B, when the input voltage signal Vi is greater than the threshold Vth1 (as shown during T1, the input voltage signal Vi is higher than the set voltage VH) or the input voltage signal Vi is less than the threshold Vth2 (as shown during T3) As shown, when the input voltage signal Vi is lower than the set voltage VL), the controller CON performs voltage equalization control to adjust the corresponding second control signal CS2.

Conversely, as shown in Figures 12A and 12B, when the input voltage signal Vi is not greater than the threshold Vth1 (as shown during T2, the input voltage signal Vi is lower than the set voltage VH) and the input voltage signal Vi is not less than the threshold Vth2 (As shown during T4, when the input voltage signal Vi is higher than the set voltage VL), the controller CON maintains the corresponding second control signal CS2.

In some embodiments, the difference between the set voltage VH and the reference voltage Vf is the same as the difference between the set voltage VL and the reference voltage Vf. In other words, the threshold Vth1 and the threshold Vth2 are the same. In other embodiments, the difference between the set voltage VH and the reference voltage Vf is different from the difference between the set voltage VL and the reference voltage Vf. In other words, the threshold Vth1 and the threshold Vth2 are different.

In addition, in some embodiments, multiple local controllers LCU1 to LCUn (or local controllers SLA1 to SLAn) in the controller CON are synchronized according to the timing flags of the main controller MCU (or the local controller MAS as the host) Obtain input voltage signals Vi1～Vin. Specifically, the synchronization flag can be generated once in every cycle or every multiple cycles. In this way, the synchronization of the local controller LCU1～LCUn (or the local controller SLA1～SLAn) can be realized by taking the time sequence of the main controller MCU (or the local controller MAS as the host) as a benchmark, ensuring the local controller LCU1 ~ LCUn (or local controller SLA1 ~ SLAn) transmits the input voltage at the same time, which makes the voltage equalization control more accurate.

Please refer to Figure 13A and Figure 13B. FIG. 13A and FIG. 13B are schematic diagrams illustrating another DC conversion system 100 according to other embodiments of the present disclosure. In the embodiment shown in FIG. 13A and FIG. 13B, elements similar to those in the embodiment in FIG. 1 are denoted by the same reference numerals. Compared with the embodiment shown in FIG. 1, in the embodiment shown in FIG. 13A, the DC conversion system 100 includes a plurality of power conversion modules MOD1 and MOD2. The power conversion modules MOD1 and MOD2 each include a plurality of conversion units DC1 to DCn, and DCn+1 to DC2n. The conversion units DC1 to DCn and DCn+1 to DC2n each include a first side and a second side.

Structurally, the first sides of the power conversion modules MOD1 and MOD2 are connected in series with each other. The second sides of the power conversion modules MOD1 and MOD2 are also connected to each other in series. In other words, on the first side of the direct current conversion system 100, the conversion units DC1 to DCn and DCn+1 to DC2n are connected in series. On the second side of the DC conversion system 100, the conversion units DC1 to DCn and DCn+1 to DC2n are each connected in parallel, and the conversion units DC1 to DCn and DCn+1 to DC2n are connected to each other in series.

In addition, in the embodiment shown in FIG. 13B, the DC conversion system 100 includes a plurality of (k) power conversion modules MOD1 to MODk. Among them, k is a positive integer greater than or equal to 1. The power conversion modules MOD1 to MODk each include at least one conversion unit (for simplicity of description, only the conversion units DC1 to DCn in the power conversion module MOD1 are drawn). Structurally, similar to Figure 13A, the first sides of the power conversion modules MOD1 to MODk are connected in series with each other, and the second sides of the power conversion modules MOD1 to MODk are also connected in series with each other. Other detailed component operations have been explained in the previous paragraphs, and will not be repeated here.

It is worth noting that the number of conversion units included in each power conversion module may be the same or not exactly the same. The drawings all show that n power conversion units are connected in parallel on the second side, which are only examples for convenience of explanation, and are not intended to limit the case.

Although the disclosed methods are shown and described herein as a series of steps or events, it should be understood that the order of these steps or events shown should not be construed in a limiting sense. For example, some steps may occur in a different order and/or simultaneously with other steps or events other than the steps or events shown and/or described herein. In addition, when implementing one or more aspects or embodiments described herein, not all the steps shown here are necessary. In addition, one or more steps in this document may also be executed in one or more separate steps and/or stages.

It should be noted that, in the case of no conflict, the features and circuits in the various drawings, embodiments, and embodiments of the present disclosure can be combined with each other. The circuit shown in the figure is only an example, and is simplified to make the description concise and easy to understand, and is not intended to limit the case. In addition, the various devices, units, and components in the foregoing embodiments can be implemented by various types of digital or analog circuits, and can also be implemented by different integrated circuit chips, or integrated into a single chip. The foregoing is only an example, and the present disclosure is not limited thereto.

To sum up, in this case, according to the input voltage signals Vi1 to Vin and the output signal Sout transmitted by each power conversion module MOD1 to MODn, the controller CON can be calculated and controlled by equalizing voltage by applying the above embodiments. A feedback signal is generated to balance the input voltage of each power conversion module MOD1 to MODn, and reduce the voltage stress of the switching transistor. Under the condition of not increasing the hardware voltage equalization circuit, the problem of voltage unevenness is solved by the control method, and the effect of reducing the cost is achieved.

In addition, this case has strong scalability, and the number of power conversion modules can be adjusted according to actual applications. In some embodiments, only the voltage signal is sampled, and the voltage equalization can be realized with a small amount of control. A simple system design can be applied to medium and high voltage applications. In other embodiments, the control interconnection between the power conversion modules can be avoided, and the possibility of interference of the circuit and the signal can be reduced. The distributed system control method can improve the reliability and redundancy of the system.

Although the content of this disclosure has been disclosed in the above manner, it is not intended to limit the content of this disclosure. Those with ordinary knowledge in the technical field can make various changes and modifications without departing from the spirit and scope of this disclosure. Therefore, this The scope of protection of the disclosed content shall be subject to the scope of the attached patent application.

100: DC conversion system 120: output sensor 140,140_1~140_n,140_n+1~140_2n,140_(k-1)n+1~140_kn,140a,140b: input voltage sensor MOD1~MODn, MODn+1~MOD2n, MOD(k-1)n+1~MODkn: power conversion module CON, CON1, CON2: Controller LOAD: load DC, DC1~DCn, DCn+1~DC2n: conversion unit Co,Ci,Ci1~Cin,Cin+1~Ci2n,Cia,Cib: Capacitance V1, V2, Vi, Vi1~Vin, Vin+1~Vi2n, Vi(k-1)n+1~Vikn, Via, Vib: Input voltage signal Sout: output signal M1~Mn, Mn+1~M2n: modulation signal 132, 132a, 132b: Full-bridge inverter circuit 134, 134a, 134b: Resonant circuit 136, 136a, 136b: Transformer 138, 138a, 138b: rectifier circuit Sig: AC signal Np: Primary winding Ns: secondary winding SW1~SW4: switch Lc: Resonant capacitance Lr: Resonant inductance Lm: Magnetizing inductance Di1~Di4: Diode MCU: main controller LCU1~LCUn,MAS,SLA1~SLAn: local controller 162_1~162_n: Error unit 164_1~164_n: Voltage stabilization control unit 166_1~166_n: superposition unit 182,182_1~182_n: Error unit 184, 184_1~184_n: Voltage stabilization control unit 186, 186_1~186_n: input reference voltage signal generator Sref: output reference signal Serr: output error value CS1, CS2, CS2_1~CS2_n: control signal Vf1~Vfn: Input reference voltage signal Vr1~Vrn: Voltage error value DSG1~DSGn: drive signal generator D1~Dn: drive signal T1, T2, T3, T4: period Vth1, Vth2: Threshold VH, VL: set voltage Vf: Reference voltage 200: Decoupling method S210, S220, S230: Operation

FIG. 1 is a schematic diagram of a DC conversion system according to some embodiments of the present disclosure. 2A and 2B are schematic diagrams illustrating a power conversion module according to some embodiments of the present disclosure. FIG. 3 is a detailed schematic diagram of a DC conversion system according to some embodiments of the present disclosure. FIG. 4 is a detailed schematic diagram of another DC conversion system according to other embodiments of the present disclosure. FIG. 5 is a schematic diagram of a controller according to some embodiments of the present disclosure. FIG. 6 is a schematic diagram showing a main controller and multiple local controllers according to some embodiments of the present disclosure. FIG. 7 is a schematic diagram showing another main controller and multiple local controllers according to some embodiments of the present disclosure. FIG. 8 is a schematic diagram of a plurality of local controllers according to other embodiments of the present disclosure. FIG. 9 is a schematic diagram of a plurality of local controllers according to other embodiments of the present disclosure. FIG. 10 is a schematic diagram showing another type of multiple local controllers according to other embodiments of the present disclosure. FIG. 11 is a schematic diagram showing another type of multiple local controllers according to other embodiments of the present disclosure. FIG. 12A and FIG. 12B are schematic diagrams illustrating a signal of a voltage equalization control according to some embodiments of the present disclosure. FIG. 13A and FIG. 13B are schematic diagrams showing another DC conversion system according to other embodiments of the present disclosure. FIG. 14 is a flowchart of a decoupling method 200 according to some embodiments of the present disclosure.

CON: Controller

162_1~162_n: Error unit

164_1~164_n: Voltage stabilization control unit

166_1~166_n: superposition unit

182: Error Unit

184: Voltage stabilization control unit

186: Input reference voltage signal generator

Sout: output signal

Sref: output reference signal

Serr: output error value

Vi1~Vin: Input voltage signal

Vf1~Vfn: Input reference voltage signal

Vr1~Vrn: Voltage error value

CS1, CS2_1~CS2_n: control signal

M1~Mn: Modulation signal

DSG1~DSGn: drive signal generator

D1~Dn: drive signal

Claims (32)

A DC conversion system includes: a plurality of power conversion modules, any one of the power conversion modules includes at least one conversion unit; the conversion units include a first side and a second side, and the The first sides are connected in series with each other, and the second sides of the conversion units are connected in parallel with each other; an output sensor for measuring an output signal of the DC conversion system; a plurality of input voltage sensors, For measuring the input voltage signals of the first sides of the conversion units respectively; and a controller coupled to the conversion units, the input voltage sensors and the output sensor, the The controller is used for: receiving the output signal and the input voltage signals; generating a first control signal according to the output signal and an output reference signal; generating a plurality of input reference voltage signals according to the input voltage signals; according to the input voltages The signal and the input reference voltage signals are voltage-balanced to generate a plurality of second control signals; and a corresponding modulation signal is output according to the corresponding one of the first control signal and the second control signals to control the conversions The unit operates in response to a plurality of switches of one. The DC conversion system according to claim 1, wherein the output The output signal is an output current signal, an output voltage signal or an output power signal. The DC conversion system according to claim 1, wherein the voltage levels of the input reference voltage signals are different. The DC conversion system according to claim 1, wherein the controller includes a main controller and a plurality of local controllers, and the main controller is coupled to the output sensor and the local controllers for receiving the Output signal and the input voltage signals, and generate the first control signal according to the output signal and the output reference signal, and generate the input reference voltage signals according to the input voltage signals, the local controllers are respectively coupled to One of the power conversion modules, one of the main controller, and one of the input voltage sensors, and the local controllers are each used to: receive the first control signal; receive the corresponding input voltage signal and Corresponding to the input reference voltage signal, and perform voltage equalization control according to the corresponding input voltage signal and the corresponding input reference voltage signal to generate the corresponding second control signal; and according to the first control signal and the corresponding first control signal The second control signal is to output the corresponding modulation signal to control the corresponding switches of the conversion unit to act. The DC conversion system of claim 4, wherein the main controller includes an error unit and a voltage stabilization control unit, the error unit receives the output signal, and subtracts the output signal from the output reference signal to obtain a An error value is output, and the voltage stabilization control unit receives and generates the first control signal according to the output error value. The DC conversion system according to claim 1, wherein the controller includes a main controller and a plurality of local controllers, and the main controller is coupled to the output sensor and the local controllers for receiving the Output signal and the input voltage signals, and generate an output error value according to the output signal and the output reference signal, and generate the input reference voltage signals according to the input voltage signals, and the local controllers are respectively coupled to the The power conversion modules correspond to one, the main controller and the input voltage sensors correspond to one, and the local controllers are each used to: receive and generate the first control signal according to the output error value; and receive the corresponding The input voltage signal and the corresponding input reference voltage signal, and perform voltage equalization control according to the corresponding input voltage signal and the corresponding input reference voltage signal to generate the corresponding second control signal; and according to the first control Signal and the corresponding second control signal to output the corresponding modulation signal to control the corresponding switches of the conversion unit to act. The DC conversion system according to claim 6, wherein the main controller includes an error unit, each of the local controllers includes a voltage stabilization control unit, and the error unit receives the output signal and references the output signal to the output The signal is subtracted to obtain the output error value, and the output error value is output to the voltage stabilization control units, and the voltage stabilization control units respectively receive and generate the first control signal according to the output error value. The DC conversion system according to claim 1, wherein the controller includes a plurality of local controllers, each of the local controllers is coupled to a corresponding one of the power conversion modules, and a corresponding one of the power conversion modules Corresponding to the input voltage sensor and the output sensor, the local controllers are each used to receive the output signal and the corresponding input voltage signal, wherein one of the local controllers is also used Receiving the input voltage signals output by others of the local controllers, and generating the input reference voltage signals according to the input voltage signals and generating the first control signal according to the output signal and the output reference signal, the Each of the local controllers is used for performing voltage equalization control according to the corresponding input voltage signal and the corresponding input reference voltage signal to generate the corresponding second control signal, and according to the first control signal and the corresponding second control signal The corresponding modulation signal is output to control the corresponding switches of the conversion unit to act. The DC conversion system according to claim 8, wherein the one of the local controllers includes an error unit and a voltage stabilization control unit, and the error unit receives the output signal and compares the output signal with the output reference signal To obtain an output error value, the voltage stabilization control unit receives and generates the first control signal according to the output error value. The DC conversion system according to claim 1, wherein the controller includes a plurality of local controllers, each of the local controllers is coupled to a corresponding one of the power conversion modules, and a corresponding one of the power conversion modules Corresponding to the input voltage sensor and the output sensor, the local controllers are each used to receive the output signal and the corresponding input voltage signal, wherein one of the local controllers is also used Receiving the input voltage signals output by the others of the local controllers, and generating the input reference voltage signals according to the input voltage signals and generating an output error value according to the output signal and the output reference signal, the local The controllers are each used to generate the first control signal according to the output error value, and the local controllers each perform voltage equalization control according to the corresponding input voltage signal and the corresponding input reference voltage signal to generate the corresponding second control Signal, and according to the first control signal and the corresponding second control signal to output the corresponding modulation signal to control the corresponding switches of the conversion unit to act. The DC conversion system according to claim 10, wherein one of the local controllers includes an error unit, and each of the local controllers includes a voltage stabilization control unit, and the error unit receives the output signal and outputs the The signal is subtracted from the output reference signal to obtain the output error value, and the output error value is respectively output to the corresponding voltage stabilization control units, and the voltage stabilization control units respectively receive and generate the first One control signal. The DC conversion system according to claim 1, wherein the controller includes a plurality of local controllers, each of the local controllers is coupled to a corresponding one of the power conversion modules, and a corresponding one of the power conversion modules Corresponding to the input voltage sensor and the output sensor, the local controllers each are used to receive the output signal and the corresponding input voltage signal, and the local controllers each include an error unit and a voltage regulator The control unit, the error unit receives the output signal, subtracts the output signal and the output reference signal to obtain an output error value, and outputs the output error value to the corresponding voltage stabilization control units, and the stabilizers The voltage control units each receive and generate the first control signal according to the output error value; wherein one of the local controllers is also used to receive the input voltage signals output by the other of the local controllers, and According to these losses The input voltage signal generates the input reference voltage signals, the local controllers each perform voltage equalization control according to the corresponding input voltage signal and the corresponding input reference voltage signal to generate the corresponding second control signal, and according to the first control signal A control signal and the corresponding second control signal are used to output the corresponding modulation signal to control the corresponding switches of the conversion unit to act. The DC conversion system according to claim 1, wherein each of the at least one conversion unit includes a DC conversion module, and the DC conversion module includes a full-bridge inverter circuit, a resonance circuit, a transformer, and a rectifier circuit, Wherein, the resonance circuit is coupled between an AC side of the full-bridge inverter circuit and a primary winding of the transformer, a secondary winding of the transformer is connected to an input side of the rectifier circuit, and the full-bridge inverter The DC side of the circuit is a first side of the DC conversion module, and an output side of the rectifier circuit is a second side of the DC conversion module. The DC conversion system according to claim 1, wherein any one of the power conversion modules includes a first side and a second side, and the first sides of the power conversion modules are connected in series with each other, The second sides of the power conversion modules are connected in series with each other. The DC conversion system according to claim 1, wherein the controller is further configured to control a first gain crossover frequency of the first control signal to be greater than a second gain crossover frequency of the second control signals. A method for controlling a DC conversion system includes: measuring an output signal of a DC conversion system by an output sensor; measuring at least one conversion unit of a plurality of power conversion modules by a plurality of input voltage sensors respectively in series with each other A plurality of input voltage signals on the first side of a plurality of first sides; a controller receives the output signal and the input voltage signals; the controller generates a first control signal according to the output signal and an output reference signal; The controller generates a plurality of input reference voltage signals according to the input voltage signals; the controller performs voltage equalization control according to the input voltage signals and the input reference voltage signals to generate a plurality of second control signals; by the controller According to the corresponding one of the first control signal and the second control signals, a corresponding modulation signal is outputted to control a plurality of switches of the corresponding one of the conversion units to operate. The DC conversion system control method of claim 16, further comprising: subtracting the output signal from the output reference signal by a main controller of the controller to obtain an output error value, wherein the first control signal is According to the output error value; the plurality of local controllers of the controller subtract the input voltage signal and the input reference voltage signal respectively received to obtain a voltage error value; and The local controllers in the controller perform voltage equalization control on the respective voltage error values to respectively generate the corresponding second control signals. The DC conversion system control method of claim 17, further comprising: receiving the output signal by an error unit of the main controller; and subtracting the output signal from the output reference signal by the error unit to obtain the output error Value; and a voltage stabilization control unit of the main controller receives and generates the first control signal according to the output error value. The DC conversion system control method of claim 16, further comprising: subtracting the output signal from the output reference signal by the main controller of the controller to obtain an output error value; The local controller generates the first control signal according to the output error value, and subtracts the corresponding input voltage signal and the corresponding input reference voltage signal respectively to obtain a corresponding voltage error value; and The controller performs voltage equalization control on the respective corresponding voltage error values to respectively generate the corresponding second control signals. The DC conversion system control method of claim 16, wherein the voltage levels of the input reference voltage signals are different. The DC conversion system control method of claim 16, further comprising: subtracting the output signal from the output reference signal by one of the plurality of local controllers of the controller to obtain an output error value, wherein the first A control signal is obtained based on the output error value; a plurality of local controllers of the controller subtract the corresponding input voltage signal and the corresponding input reference voltage signal respectively to obtain a corresponding voltage error value; And the local controllers perform voltage equalization control on the corresponding voltage error values to respectively generate the corresponding second control signals. The DC conversion system control method of claim 16, further comprising: subtracting the output signal from the output reference signal by one of the plurality of local controllers of the controller to obtain an output error value; The plurality of local controllers of the device will generate the first control signal according to the output error value, and respectively subtract the corresponding input voltage signal and the corresponding input reference voltage signal to obtain a corresponding voltage error value; and The local controllers in the controller perform voltage equalization control on the corresponding voltage error values to respectively generate the corresponding second control signals. The DC conversion system control method described in claim 17, 19, 21 or 22 further includes: When one of the voltage error values is greater than a first threshold or less than a second threshold, the controller performs voltage equalization control to adjust the corresponding second control signal; and when one of the voltage error values If it is not greater than the first threshold and not less than the second threshold, the controller maintains the corresponding second control signal. The DC conversion system control method according to claim 23, wherein the second threshold is different from the first threshold. The DC conversion system control method of claim 16, further comprising: adding the first control signal and the second control signals to generate and output the modulation signals by the controller. The control method of the DC conversion system according to claim 17 or 19, further includes: obtaining the input voltage signals synchronously by a plurality of local controllers in the controller according to a timing mark of the main controller in the controller. The DC conversion system control method of claim 16, further comprising: controlling a first gain crossover frequency of the first control signal by the controller to be greater than a second gain crossover frequency of the second control signals. A decoupling method suitable for a total output signal control loop and a voltage equalization control loop of a DC conversion system. The total output signal control loop is used to generate a first control signal, and the voltage equalization control loop is used to generate a plurality of The second control signal. The decoupling method includes: detecting the second control signals by a controller; determining whether the second control signals are out of a coupling tolerance range by the controller; and when the second control signals are If the signal exceeds the coupling tolerance range, the controller compensates the first control signal and the second control signals, wherein the compensation direction of the controller for the first control signal is opposite to the compensation for the second control signals direction. The decoupling method according to claim 28, further comprising: determining by the controller whether the second control signals are all greater than a coupling tolerance upper limit value or all are less than a coupling tolerance lower limit value; when the second control signals are all greater than a coupling tolerance upper limit value or less than a coupling tolerance lower limit value; If the signals are all greater than the coupling tolerance upper limit, the controller subtracts a compensation value from the second control signals, and adds the compensation value to the first control signal; and when the second control signals are all If it is less than the coupling tolerance lower limit, the controller adds the compensation value to the second control signals, and subtracts the compensation value from the first control signal. The decoupling method according to claim 28, wherein the total output signal control loop can be a total output voltage control loop, a total output voltage control loop Flow control loop, or a total output power control loop. The decoupling method according to claim 28, wherein the first control signal and the second control signals are both a switching frequency, a counter value, or a duty cycle value. The decoupling method according to claim 28, wherein the first control signal is one of a switching frequency, a counter value, and a duty cycle value, and the second control signals are one of a switching frequency, a counter value, and a duty cycle value The other.

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