TWI728728B - Smart grid system and power management method thereof - Google Patents

Abstract

A smart grid system includes a current measurement unit, and plural power conversion devices coupled to the AC grid. The current measurement unit measures a total current flowed through the AC grid, thereby providing a measured current value. The power conversion devices include a master power conversion device and plural slave power conversion devices. The master power conversion device is configured to control an output power of the master power conversion device according to the measured current value and to provide a first duty signal. A first one of the slave power conversion devices which is coupled with the master power conversion device controls an output power of the first one of the slave power conversion devices according to the first duty signal. The master power conversion device and the slave power conversion devices are communicated via a daisy chain manner.

Description

Smart grid system and its power management method

The embodiment of the disclosure relates to a smart grid system, and particularly relates to a smart grid system and a power management method thereof.

In the conventional smart grid, the power purchase and sale between the user end and the power supply end of the power grid requires a monitoring system (such as a remote control system (RCS)), so that the power conversion device at the user end can accept the power control of the power company . The above-mentioned monitoring system needs to receive the electrical information of the main line measured by the power meter, and analyze it, and then use the corresponding communication method (such as RS-485 communication or wireless fidelity). (WiFi), etc.) Send commands to each power conversion device on the user side, so that the power conversion device on the user side can emit energy that meets the demand. However, some users do not need to sell electricity for their own use, and still need a monitoring system to prevent the conversion device from accidentally supplying power to the power grid without being under the control of the power company. However, due to the above-mentioned communication process for each power conversion device There will be unavoidable transmission, waiting, receiving, polling and other time delays. Therefore, it is likely that the energy cannot be regulated within the specified time due to the inability to respond immediately, thereby violating the current regulatory requirements.

The purpose of this disclosure is to propose a smart grid system that is applied to loads and AC power grids. The smart grid system includes: a current measurement unit and a plurality of conversion devices. The current measurement unit is used to measure the total current flowing through the AC power grid to provide a current measurement value. The plurality of conversion devices are coupled to the AC power grid and used to supply power to the load. The multiple conversion devices include: a master conversion device and a plurality of slave conversion devices. The main control conversion device is used for receiving the current measurement value and controlling the output power of the main control conversion device according to the current measurement value and providing a first duty signal. The first of the plurality of slave conversion devices coupled to the master conversion device is used for receiving the first duty signal and controlling the plurality of slave conversion devices according to the first duty signal The output power of the first. The master conversion device and the plurality of slave conversion devices communicate in a daisy chain manner.

In some embodiments, the first of the plurality of slave conversion devices is further used to provide a second duty signal according to the first duty signal.

In some embodiments, the second one of the plurality of slave conversion devices is used to receive the second duty signal and control the output of the second one of the plurality of slave conversion devices according to the second duty signal power.

In some embodiments, each of the plurality of conversion devices includes: a DC input port for receiving DC power, an AC output port for outputting AC power, and a microcontroller unit. The microcontroller unit is used to control the AC power at least according to the DC power supply.

In some embodiments, each of the plurality of conversion devices further includes a current measurement port. The current measurement port of the main control conversion device is used for receiving the current measurement value.

In some embodiments, the microcontroller unit of the above-mentioned main control conversion device is used to control all the output from the AC output port of the main control conversion device according to the DC power supply and the current measurement value. Said alternating current.

In some embodiments, each of the above-mentioned multiple conversion devices further includes an input/output port. The input/output port of the master conversion device is used to provide the first duty signal. The input/output port of the first one of the plurality of slave conversion devices is used for receiving the first duty signal and used for providing the second duty signal.

In some embodiments, the microcontroller unit of the first one of the plurality of slave conversion devices is used to control the first of the plurality of slave conversion devices according to the DC power source and the first duty signal. The alternating current output from the alternating current output port of the person.

In some embodiments, the above-mentioned main control conversion device determines the flow direction of the total current according to the current measurement value, and the main control conversion device controls the main control conversion device according to the flow direction of the total current And provide the first duty signal.

In some embodiments, the above-mentioned main control conversion device controls the output power of the main control conversion device and provides the first duty signal by determining whether the current measurement value is less than the current setting value.

The purpose of this disclosure is to provide another power management method for a smart grid system, including: measuring the total current flowing through the AC power grid to provide a current measurement value; The control conversion device receives the current measurement value, wherein the main control conversion device controls the output power of the main control conversion device according to the current measurement value and provides a first duty signal; and The first of the plurality of slave conversion devices of the plurality of conversion devices coupled to the master conversion device receives the first duty signal, wherein the first of the plurality of slave conversion devices is based on the first A duty signal is used to control the output power of the first of the plurality of slave conversion devices. The multiple conversion devices are used to supply power to the load. The master conversion device and the plurality of slave conversion devices communicate in a daisy chain manner.

In some embodiments, the first of the plurality of slave conversion devices provides a second duty signal according to the first duty signal.

In some embodiments, the power management method of the above-mentioned smart grid system further includes: receiving the second duty signal by a second of the plurality of slave conversion devices, wherein the first of the plurality of slave conversion devices Both control the output power of the second one of the plurality of slave conversion devices according to the second duty signal.

In some embodiments, the above-mentioned main control conversion device determines the flow direction of the total current according to the current measurement value, and the main control conversion device controls the main control conversion device according to the flow direction of the total current And provide the first duty signal.

In some embodiments, when the direction of the total current flows to the load, the main control conversion device increases the duty cycle of the first duty signal; when the direction of the total current flows to the load Load, the main control conversion device reduces the duty cycle of the first duty signal.

In some embodiments, after increasing or decreasing the duty cycle of the first duty signal, the main control conversion device again determines the flow direction of the total current; when the flow direction of the total current flows to the load The main control conversion device does not adjust the duty ratio of the first duty signal; when the total current does not flow to the load, the main control conversion device reduces the duty of the first duty signal ratio.

In some embodiments, the above-mentioned main control conversion device controls the output power of the main control conversion device and provides the first duty signal by determining whether the current measurement value is less than the current setting value.

In some embodiments, when the current measurement value is less than the current setting value, the main control conversion device increases the duty cycle of the first duty signal; when the current measurement value is not less than the The current setting value, the main control conversion device reduces the duty ratio of the first duty signal.

In some embodiments, after the above-mentioned increase or decrease of the duty ratio of the first duty signal, the main control conversion device again determines whether the current measurement value is less than the current setting value; when the current When the measured value is less than the current setting value, the main control conversion device does not adjust the duty ratio of the first duty signal; when the current measurement value is not less than the current setting value, the main control conversion The device reduces the duty cycle of the first duty signal.

In some embodiments, the first of the plurality of slave conversion devices determines whether the duty cycle of the first duty signal decreases; when the duty cycle of the first duty signal decreases, the plurality of slave conversion devices The first of the conversion devices reduces the output power of the first of the plurality of slave conversion devices; when the duty cycle of the first duty signal does not decrease, the first of the plurality of slave conversion devices determines Whether the output power of the first of the plurality of slave conversion devices reaches its own maximum power of the first of the plurality of slave conversion devices; when the output power of the first of the plurality of slave conversion devices reaches the own maximum power Maximum power, the first of the plurality of slave conversion devices does not adjust the output power of the first of the plurality of slave conversion devices; when the output power of the first of the plurality of slave conversion devices does not reach the For its own maximum power, the first of the plurality of slave conversion devices increases the output power of the first of the plurality of slave conversion devices.

In order to make the above-mentioned features and advantages of the present disclosure more obvious and understandable, the following specific embodiments are described in detail in conjunction with the accompanying drawings.

The embodiments of the present invention are discussed in detail below. However, it can be understood that the embodiments provide many applicable concepts, which can be implemented in various specific contents. The discussed and disclosed embodiments are for illustrative purposes only, and are not intended to limit the scope of the present invention. Regarding the "first", "second", "third", etc. used in this text, it does not specifically refer to the order or sequence, but only distinguishes elements or operations described in the same technical terms.

FIG. 1 is a schematic diagram of the architecture of a smart grid system 100 according to an embodiment of the disclosure. The smart grid system 100 includes: an AC power grid 110, a current measuring unit 120, a load 130, conversion devices 140 ₀ , 140 ₁ , 140 _2, and DC power supply devices 150 ₀ , 150 ₁ , 150 ₂ .

As shown in FIG. 1, the conversion devices 140 ₀ , 140 ₁ , and 140 _{2 are} coupled to the AC power grid 110 and to the load 130. In the embodiment of the present disclosure, the load 130 can be used to represent a general household load or any load that accepts AC power. As shown in FIG. 1, the conversion devices 140 ₀ , 140 ₁ , and 140 ₂ are respectively coupled to the DC power supply devices 150 ₀ , 150 ₁ , and 150 _2. In the embodiment of the disclosure, each of the DC power supply devices 150 ₀ , 150 ₁ , 150 ₂ may include regenerative power sources, secondary batteries, or other devices that can provide DC power sources. In the disclosed embodiment, the conversion devices 140 ₀ , 140 ₁ , and 140 ₂ respectively receive DC power from the DC power supply devices 150 ₀ , 150 ₁ , and 150 ₂ and output AC power to the load 130.

As shown in FIG. 1, the current measuring unit 120 is coupled between the AC power grid 110 and the conversion device 140 ₀ . In the disclosed embodiment, the current measuring unit 120 may be a current transformer (CT) or a Hall sensor (Hall Sensor), which is used to measure the total current flowing through the AC power grid 110 to provide The current measurement value (that is, the current value flowing through the main line) is sent to the conversion device 140 ₀ . In the embodiment of the present disclosure, the direction of the total current flowing through the AC power grid 110 can also be obtained according to the current measurement value provided by the current measurement unit 120.

The conversion devices 140 ₀ , 140 ₁ , and 140 ₂ include a master (Master) conversion device 140 ₀ and a slave (Slave) conversion device 140 ₁ , 140 ₂ . FIG. 2a is a schematic structural diagram _{of the master conversion device 140 0} of the smart grid system 100 according to an embodiment of the disclosure. Figure 2b slave system architecture diagram of the conversion apparatus of the present disclosure smart grid system 100 according to an embodiment of the _1401's. FIG. 2c is a schematic structural diagram _{of the slave conversion device 140 2} of the smart grid system 100 according to an embodiment of the disclosure.

It should be noted that the number of the aforementioned slave conversion devices 140 ₁ and 140 ₂ may vary with different application scenarios, and is not limited to two.

As shown in FIGS. 2a, 2b, and 2c, each of the master conversion device 140 ₀ and the slave conversion devices 140 ₁ and 140 ₂ may include a DC-to-DC converter 11 (DC-to-DC converter) and an inverter 12 (DC-to-AC converter), sensor 13, circuit breaker 14, micro control unit 15, communication unit 16, communication port 17, current/voltage measurement unit 18, input/output (Input/Output, I/O ) Port I/O ₁ , I/O _2, and current measurement port CT.

Each of the master conversion device 140 ₀ and the slave conversion devices 140 ₁ and 140 ₂ further includes a DC input port IN and an AC output port OUT. The DC input ports IN of the master conversion device 140 ₀ and the slave conversion devices 140 ₁ , 140 ₂ are respectively arranged between the DC power supply devices 150 ₀ , 150 ₁ , 150 ₂ and the DC converter 11, the master conversion device 140 ₀ and the slave converters 11 The conversion devices 140 ₁ and 140 ₂ respectively receive the DC power output from the DC power _{supply devices 150 0} , 150 ₁ , and 150 ₂ from the DC input port IN. The AC output port OUT is set between the circuit breaker 14 and the AC power grid 110, and the master conversion device 140 ₀ and the slave conversion devices 140 ₁ and 140 ₂ output AC power to the AC power grid 110 from the AC output port OUT.

The DC converter 11 is used for receiving DC power from the DC input port IN and performing conversion to output the converted DC power, for example, as a DC converter for boosting the DC power. The inverter 12 is used to convert the converted DC power output from the DC converter 11 into AC power. The sensor 13 is used to sense the alternating current output by the inverter 12. The circuit breaker 14 is used to confirm that its corresponding conversion device (140 ₀ , 140 ₁ or 140 ₂ ) can normally output the alternating current converted by the inverter 12, and then the circuit breaker 14 is turned on and put into operation, so that the alternating current is passed from the AC output port OUT is output and integrated into the AC power grid 110.

The current/voltage measuring unit 18 is used to measure the current/voltage that needs to be measured inside the _{conversion device (140 0} , 140 ₁ or 140 _{2 ).} The current/voltage measurement unit 18 transmits the measured current/voltage to the micro-control unit 15. The micro-control unit 15 multiplies the received current/voltage to obtain power information.

The micro control unit 15 may be a microcontroller (Micro Control Unit, MCU), a microprocessor (Micro Processor Unit, MPU), an application-specific integrated circuit (ASIC), or a system on a chip (System on a chip). Chip, SoC) one of them.

In the conventional smart grid system, the calculated power information (which may also include current and voltage information) is transmitted through the communication unit 16 in a wireless (wireless) form (such as wireless fidelity (WiFi)) or via the communication port 17. Wired (such as RS-485 or CAN bus) communication methods are connected to the monitoring system, and then communicate with the management center (such as private or state-owned power companies or power utilities) for the management center to perform power dispatch or The basis of power management is to realize the mastery, integration and management of power information in the smart grid system. However, in applications that require only self-use without selling electricity, there will be unavoidable transmission, waiting, receiving, polling and other time delays during the process of this architecture communication method, so it is likely to be unable to respond immediately And fail to regulate the energy within the stipulated time, thus violating the current regulatory requirements.

FIG. 3 is a schematic diagram of the communication mode of the smart grid system 100 according to an embodiment of the disclosure. As shown in FIG. 3, the master conversion device 140 ₀ and the slave conversion devices 140 ₁ and 140 ₂ communicate in a daisy chain manner. In other words, the master conversion device 140 ₀ and the slave conversion devices 140 ₁ , The 140 ₂ is serially connected one by one in a daisy chain through the input/output ports I/O ₁ and I/O _2. Please refer to FIGS. 2a, 2b, 2c, and 3 together. In the disclosed embodiment, _{the current measurement port CT of the main control conversion device 140 0} is used to receive the current measured by the current measurement unit 120 Measured value. The micro-control unit 15 of the main control conversion device 140 ₀ is used to control the output of the AC output port OUT of the _{main control conversion device 140 0 according to the DC power output by the DC power supply device 150 0} and the current measurement value output by the current measurement unit 120 AC, in other words, the micro control unit ₁₄₀₀ of the main switching means 15 for outputting to the main control means according to current measurement value converter 120 outputs the output of the DC power supply ₁₅₀₀ a DC power supply device and the current measuring unit ₁₄₀₀ power. In addition, the micro-control unit 15 of the master conversion device 140 ₀ is also used to provide a first duty signal to the master _{through the input/output port I/O 2} according to the current measurement value output by the current measurement unit 120. The communication mode of the control conversion device 140 ₀ is the slave conversion device 140 ₁ coupled in series.

The input/output port I/O _{1 of the} slave conversion device 140 ₁ is used to receive the first duty signal provided by the master conversion device 140 _{0 , and the micro-control unit 15 of the slave conversion device 140 1} is used to respond to the DC power supply device 150 _a DC power output to the first duty control signal to the slave device converting alternating current AC output OUT of the output _1401, in other words, the slave converter ₁₄₀₁ to the micro control unit 15 according to the output of the DC power supply 150 ₁ DC power source and a first duty signal to control the output power of the slave converter ₁₄₀₁ is. In addition, the micro-control unit 15 of the slave conversion device 140 ₁ is also used to provide a second duty signal to the slave conversion device 140 ₁ through the input/output port I/O ₂ according to the first duty signal. The communication method with the slave conversion device 140 1 is series coupling. Connected to the slave conversion device 140 ₂ .

Slave converter ₁₄₀₂ input / output port I / O ₁ slave converter means for receiving a second duty signal provided by _1401, and the slave converter ₁₄₀₂ in the micro control unit 15 according to a second duty signal slave control means for converting alternating current AC ₁₄₀₂ output from the output port OUT is, in other words, the slave converter ₁₄₀₂ of the micro control unit 15 for controlling the output power of the slave converter ₁₄₀₂ according to a second duty signal.

In the disclosed embodiment, the above-mentioned first duty signal and second duty signal are the duty ratio (Duty Ratio or Duty Cycle) generated by using Pulse Width Modulation (PWM) to modulate the square wave. ) Is a square wave signal from 0% to 100%. In an embodiment of the present disclosure, the greater the duty cycle of the first duty signal, the output power of the slave converter ₁₄₀₁ is also greater. In other words, when the master conversion device 140 ₀ increases the duty ratio of the first duty signal provided by it, _{the output power of the slave conversion device 140 1} also increases; when the master conversion device 140 ₀ reduces the duty ratio of the first duty signal provided by it, the output power of the slave conversion device 140 1 also increases; With the duty ratio of the first duty signal, _{the output power of the slave conversion device 140 1} is also reduced accordingly. In an embodiment of the present disclosure, the second duty ratio greater duty signal, the output power of the slave converter ₁₄₀₂ is also greater. In other words, when the slave conversion device 140 ₁ increases the duty cycle of the second duty signal provided by it, _{the output power of the slave conversion device 140 2} also increases; when the slave conversion device 140 ₁ decreases the second duty cycle provided by the slave conversion device 140 1 With the duty ratio of the duty signal, _{the output power of the slave conversion device 140 2} is also reduced accordingly. However, the trend of duty cycle and output power is not limited to this, and the opposite configuration can also be set. For example, the larger the duty cycle, the output power will decrease accordingly.

Compared with the conventional smart grid system, the smart grid system 100 of the embodiment of the present disclosure does not require an additional monitoring system to monitor the electrical information of the main line and to control the power of each conversion device through communication. Therefore, the present disclosure The smart grid system 100 of this embodiment does not need to configure complicated peripheral lines, which can not only reduce the cost of installing the device, but also reduce the labor and time cost of maintaining the device, and it can also reduce the probability of electromagnetic interference due to the reduction of intensive line configuration. In turn, the loss of transmission power is reduced, so as to save manpower and time, simplify peripheral circuits, reduce electromagnetic interference, and reduce hardware costs.

In addition, compared with the conventional smart grid system, the smart grid system 100 of the disclosed embodiment does not use a monitoring system to communicate with each conversion device by means of wireless fidelity (WiFi), RS-485, or CAN bus, etc. _{To send commands, the master conversion device 140 0} and the slave conversion devices 140 ₁ , 140 ₂ of the smart grid system 100 of the embodiment of the present disclosure communicate in a daisy chain manner and through input/ The output ports I/O ₁ and I/O _{2 are} used to transmit commands (the first duty signal, the second duty signal). The daisy-chain communication method is independent, and the energy of the transmitted command is determined by the previous conversion device. Provide, avoid unnecessary transmission, waiting, receiving, polling and other time delays. Specifically, the smart grid system 100 of the embodiment of the present disclosure has a relatively small time delay, so that it can respond instantly and regulate energy within a specified time to meet current regulatory requirements.

FIG. 4 is a flowchart of a power management method 1000 of the smart grid system 100 according to an embodiment of the disclosure. Please refer to FIG. 1 and FIG. 4 together, the power management method 1000 includes steps 1100-1400. In step 1100, the current measurement unit 120 of the smart grid system 100 measures the total current flowing through the AC power grid 110 to provide a current measurement value. In step 1200, ₁₄₀₀ from the current measuring unit 120 receives the measured value of the master current conversion means and switching means ₁₄₀₀ to the master control of the control means output power converter ₁₄₀₀ according to a first current measurement values and provides accounting The communication mode from the empty signal to the master conversion device 140 ₀ is the slave conversion device 140 ₁ coupled in series. In step 1300, the slave converter ₁₄₀₁ converts autonomous control means ₁₄₀₀ receives the first duty signal, and the slave converter ₁₄₀₁ converting apparatus according to a first slave control duty signal output ₁₄₀₁ and a second duty The communication mode of the signal to the slave conversion device 140 ₁ is the slave conversion device 140 ₂ coupled in series. In step 1400, the slave converter ₁₄₀₂ since ₁₄₀₂ to control the switching means according to a second slave signal output duty slave converter ₁₄₀₂ genus converting apparatus ₁₄₀₁ receives the second duty signal, and.

5 is a flowchart of a first application example of the power control method of _{the master conversion device 140 0} and the slave conversion device 140 ₁ of the smart grid system 100 according to the embodiment of the disclosure. As shown in FIG. 5, in step 2100, the main control conversion device 140 _{0 of the} smart grid system 100 receives the current measurement value from the current measurement unit 120, and the main control conversion device 140 ₀ determines the current flow through the AC according to the current measurement value. The direction of the total current flow of the grid 110. Next, in step 2200, the main control conversion device 140 ₀ determines whether the total current flowing through the AC power grid 110 flows to the load 130. If the total current of the AC power grid 110 flows to the load, it can be understood as the power provided by all conversion devices. Not enough for the load. When the main control conversion device 140 ₀ determines that the direction of the total current flowing through the AC power grid 110 flows to the load 130, step 2300 is entered; when the main control conversion device 140 ₀ determines that the direction of the total current flowing through the AC power grid 110 does not flow to the load 130, go to step 2400. In step 2300, the master switching means ₁₄₀₀ increases the output power of the master switching means _1400, and the master converter ₁₄₀₀ increases the first duty so that the duty cycle of the slave empty signal conversion means ₁₄₀₁ increases the output power, And then go to step 2500. In step 2400, the master unit ₁₄₀₀ converts the output power of the master to reduce the conversion means _1400, and the main switching means ₁₄₀₀ reduces the duty cycle of the first account so that the slave empty signal converting means reduces the output power of 140 _1, And then go to step 2500. In step 2500, the main control conversion device 140 ₀ receives the current measurement value from the current measurement unit 120 again, and the main control conversion device 140 ₀ again determines the direction of the total current flowing through the AC power grid 110 based on the current measurement value. Next, in step 2600, the main control conversion device 140 ₀ again determines whether the total current flowing through the AC power grid 110 flows to the load 130. When the main control conversion device 140 ₀ determines the flow direction of the total current flowing through the AC power grid 110 To load 130, the main control conversion device 140 ₀ does not adjust the duty ratio of the first duty signal, and the entire flow chart is executed repeatedly; when the main control conversion device 140 ₀ determines that the total current flowing through the AC grid 110 is not flowing To load 130, go back to step 2400.

_{Specifically, the first application example of the power control method of the master conversion device 140 0} and the slave conversion device 140 ₁ of the smart grid system 100 of the present disclosure is that the AC power output by the conversion device only flows to the load 130 and does not flow to The application example of the AC grid 110 means an application method that does not sell electricity to the power company for self-regulation. Application of this first embodiment, the master system conversion apparatus ₁₄₀₀ according to the total flow of current through the AC grid 110 to the main control means outputs the power converter _1400, the converter ₁₄₀₀ and the master exchange system according flowing The flow of the total current of the power grid 110 adjusts the duty ratio of the first duty signal to regulate the output power of the _{slave conversion device 140 1.}

6 is a flowchart of a second application example of the power control method of _{the master conversion device 140 0} and the slave conversion device 140 ₁ of the smart grid system 100 according to the embodiment of the present disclosure. As shown in FIG. 6, in step 3100, the main control conversion device 140 _{0 of the} smart grid system 100 receives the current measurement value from the current measurement unit 120, and the main control conversion device 140 ₀ determines whether the current measurement value is less than the current setting value. , Wherein the current setting value is, for example, a current threshold value set by an operating personnel's application situation or a current threshold value transmitted to the main control conversion device through any device. Then, in step 3200, when the main control conversion device 140 ₀ determines that the current measurement value is less than the current setting value, then step 3300 is entered; when the main control conversion device 140 ₀ determines that the current measurement value is not less than the current setting value, then step 3400 is entered . In step 3300, the master switching means ₁₄₀₀ increases the output power of the master switching means _1400, and the master converter ₁₄₀₀ increases the first duty so that the duty cycle of the slave empty signal conversion means ₁₄₀₁ increases the output power, And then enter step 3500. In step 3400, the master converting means ₁₄₀₀ reduces the output power of the master switching means _1400, and the main switching means ₁₄₀₀ reduces the duty cycle of the first account so that the slave empty signal converting means reduces the output power of 140 _1, And then enter step 3500. In step 3500, the main control conversion device 140 ₀ receives the current measurement value from the current measurement unit 120 again, and the main control conversion device 140 ₀ again determines whether the current measurement value is less than the current setting value. Next, in step 3600, when the main control conversion device 140 ₀ determines that the current measurement value is less than the current setting value, the main control conversion device 140 ₀ does not adjust the duty ratio of the first duty signal; when the main control conversion device 140 ₀ determines If the current measurement value is not less than the current setting value, go back to step 3400.

_{Specifically, the second application example of the power control method of the master conversion device 140 0} and the slave conversion device 140 ₁ of the smart grid system 100 of the present disclosure is to limit the output of the smart grid system 100 to the The energy of the AC power grid, in other words, the second application example allows the AC power output by the conversion device to flow to the AC power grid 110, that is, the application method of selling electricity to the power company for self-regulation. Application of this second embodiment, the master system conversion apparatus ₁₄₀₀ is determined by the measured current value is less than the current set value to the main control means outputs the power converter _1400, the converter ₁₄₀₀ and the host system is determined by current measurement value is smaller than a first current set value representing the duty cycle is adjusted empty signals, means to regulate the output power of the slave converter ₁₄₀₁ is. The second application example differs from the first application example only in the current setting value. The first application example sets the current setting value to avoid output of current to the AC grid, while the second application example can increase the current setting value according to the demand and allow the current Output to AC grid.

FIG. 7 is a flowchart of an application example of the self-power control method of _{the slave conversion device 140 1} and/or 140 ₂ of the smart grid system 100 according to the embodiment of the disclosure. As shown in FIG. 7, in step 4100, the slave conversion device of the smart grid system 100 determines whether the duty cycle of the received duty signal is reduced. For example, the slave conversion device 140 ₁ determines whether the duty cycle of the received first duty signal is decreased. For another example, the slave conversion device 140 ₂ determines whether the duty cycle of the received second duty signal decreases. Then, in step 4200, when the slave conversion device determines that the duty cycle of the received duty signal has decreased, it proceeds to step 4300; when the slave conversion device determines that the duty cycle of the received duty signal has not decreased, it enters Step 4400. In step 4300, the slave conversion device reduces its output power. For example, when the slave converter ₁₄₀₁ determines whether the received first signal representing the duty cycle is decreased empty, slave converter ₁₄₀₁ to reduce the output power of the slave converter and the slave converter ₁₄₀₁ to decrease the second device ₁₄₀₁ The duty cycle of the duty signal. For another example, when the slave conversion device 140 ₂ determines that the duty ratio of the received second duty signal is decreased, the slave conversion device 140 ₂ reduces the output power of the slave conversion device 140 _2. In step 4400, the slave conversion device determines whether its output power has reached its own maximum power, and then proceeds to step 4500. For example, the slave converter ₁₄₀₁ determines whether the output power of the slave converter ₁₄₀₁ itself reaches the maximum power conversion apparatus ₁₄₀₁ is the slave. For another example, the slave converter ₁₄₀₂ determines whether the output power of the slave converter ₁₄₀₂ converting means slave itself reaches the maximum power of _1402. In step 4500, when the slave conversion device determines that its output power reaches its own maximum power, the slave conversion device does not adjust its output power; when the slave conversion device determines that its output power does not reach its own maximum power, step 4600 is entered. In step 4600, the slave conversion device increases its output power. When For example, when the slave converter ₁₄₀₁ determines the output power of the slave converter ₁₄₀₁ does not reach the maximum power of the slave converter ₁₄₀₁ itself, the slave converter ₁₄₀₁ to increase the output power of the slave converter ₁₄₀₁ and slave converter 140 ₁ Increase the duty cycle of the second duty signal. When For another example, when the slave converter ₁₄₀₂ determines the output power of the slave converter ₁₄₀₂ itself does not reach the maximum power conversion device 140 slave _2, slave converter ₁₄₀₂ to increase the output power of the slave converter ₁₄₀₂ is.

Specifically, the application example of the self-power control method of _{the slave conversion device 140 1} and/or 140 ₂ of the smart grid system 100 in the embodiment of the present disclosure _{describes that the slave conversion device 140 1} /140 ₂ is based on the received first The duty cycle of the first/second duty signal and its own maximum power regulate its output power.

It is worth mentioning that in the embodiment of the present disclosure, in order to comply with the current regulatory requirements, the output power of the conversion device needs to be reduced within a certain period of time so that energy is not transmitted to the AC power grid. Therefore, the smart grid of the embodiment of the present disclosure is The system allows the output power of the conversion device to be increased at a relatively slow speed, and the increase of the output power of the conversion device can be that the output power of all the conversion devices increase at the same time, or the output power of each conversion device is at different time points. Individual increases. However, in order to comply with current regulatory requirements, it is required to simultaneously reduce the output power of all the conversion devices at a relatively fast speed, so as to reduce the output power of the conversion devices in real time. The smart grid system of the embodiment of the present disclosure balances its own grid through the above-mentioned mechanism.

In summary, this disclosure proposes a smart grid system and a power management method for the smart grid system. A master control conversion device is used to use the current measurement value of the total current flowing through the AC grid as the basis for power dispatch or power management. , In order to adjust the output power of each conversion device, so as to realize the mastery, integration and management of the power information of the smart grid system, and at the same time to meet the current regulatory requirements.

The features of several embodiments are summarized above, so those who are familiar with the art can better understand the aspect of the present disclosure. Those who are familiar with this art should understand that they can easily use the present disclosure as a basis to design or modify other processes and structures, thereby achieving the same goals and/or the same advantages as the embodiments described herein. . Those who are familiar with this technique should also understand that these equivalent constructions do not depart from the spirit and scope of this disclosure, and they can make various changes, substitutions and alterations without departing from the spirit and scope of this disclosure.

100: Smart grid system 110: AC power grid 120: Current measurement unit 130: Load 140 ₀ , 140 ₁ , 140 ₂ : Conversion device 150 ₀ , 150 ₁ , 150 ₂ : DC power supply device 1000: Power management method 1100~1400, 2100~2600, 3100~3600, 4100~4600: Step 11: DC converter 12: Inverter 13: Sensor 14: Circuit breaker 15: Micro control unit 16: Communication unit 17: Communication port 18: Current/voltage Measurement unit IN: DC input port OUT: AC output port I/O ₁ , I/O ₂ : Input/output port CT: Current measurement port

From the following detailed description in conjunction with the accompanying drawings, a better understanding of the aspect of the present disclosure can be obtained. It should be noted that, according to industry standard practice, each feature is not drawn to scale. In fact, in order to make the discussion clearer, the size of each feature can be increased or decreased arbitrarily.

[Figure 1] is a schematic diagram of the architecture of a smart grid system according to an embodiment of the disclosure.

[Figure 2a] is a schematic diagram of the architecture of the master conversion device of the smart grid system according to the embodiment of the disclosure.

[Fig. 2b] and [Fig. 2c] are schematic diagrams of the structure of the slave conversion device of the smart grid system according to the embodiment of the disclosure.

[Fig. 3] is a schematic diagram of the communication mode of the smart grid system according to the embodiment of the disclosure.

[Fig. 4] is a flowchart of a power management method of a smart grid system according to an embodiment of the disclosure.

[Fig. 5] is a flowchart of the first application example of the power control method of the master conversion device and the slave conversion device of the smart grid system according to the embodiment of the present disclosure.

[Fig. 6] is a flowchart of a second application example of the power control method of the master conversion device and the slave conversion device of the smart grid system according to the embodiment of the disclosure.

[Fig. 7] is a flowchart of an application example of the self-power control method of the slave conversion device of the smart grid system according to the embodiment of the disclosure.

100: Smart grid system

110: AC grid

120: Current measurement unit

130: load

140 ₀ ,140 ₁ ,140 ₂ : Conversion device

150 ₀ ,150 ₁ ,150 ₂ : DC power supply device

Claims (20)

A smart grid system applied to a load and an AC power grid, including: A current measurement unit for measuring a total current flowing through the AC grid to provide a current measurement value; and A plurality of conversion devices are coupled to the AC power grid and used to supply power to the load, wherein the conversion devices include: A main control conversion device for receiving the current measurement value and controlling the output power of the main control conversion device according to the current measurement value and providing a first duty signal; and A plurality of slave conversion devices, wherein a first of the slave conversion devices coupled to the master conversion device is used for receiving the first duty signal and controlling the slave conversion devices according to the first duty signal The output power of the first person; The master conversion device and the slave conversion devices communicate in a daisy chain manner. The smart grid system according to claim 1, wherein the first of the slave conversion devices is further used to provide a second duty signal according to the first duty signal. The smart grid system according to claim 2, wherein a second of the slave conversion devices is used to receive the second duty signal and control the second of the slave conversion devices according to the second duty signal The output power of the person. The smart grid system according to claim 2, wherein each of the conversion devices includes: A DC input port for receiving DC power; An AC output port for outputting an AC power; and A microcontroller unit is used to control the AC power at least according to the DC power supply. The smart grid system according to claim 4, wherein each of the conversion devices further includes a current measurement port, and the current measurement port of the master conversion device is used to receive the current measurement value. The smart grid system according to claim 4, wherein the microcontroller unit of the main control conversion device is used to control the output of the AC output port of the main control conversion device according to the DC power source and the current measurement value The alternating current. The smart grid system according to claim 4, wherein each of the conversion devices further includes an input/output port, wherein the input/output port of the master conversion device is used to provide the first duty signal, wherein the The input/output port of the first one of the slave conversion devices is used for receiving the first duty signal and used for providing the second duty signal. The smart grid system according to claim 4, wherein the microcontroller unit of the first one of the slave conversion devices is used to control the slave conversion devices according to the DC power source and the first duty signal The AC output from the AC output port of the first. The smart grid system according to claim 1, wherein the main control conversion device determines the flow direction of the total current according to the current measurement value, and the main control conversion device controls the main control conversion according to the flow direction of the total current The output power of the device and the first duty signal are provided. The smart grid system according to claim 1, wherein the main control conversion device controls the output power of the main control conversion device and provides the first duty signal by determining whether the measured current value is less than a current setting value . A power management method for a smart grid system includes: Measure a total current flowing through an AC power grid to provide a current measurement value; A main control conversion device of a plurality of conversion devices coupled to the AC power grid receives the current measurement value, wherein the main control conversion device controls the output power of the main control conversion device according to the current measurement value and Provide a first occupancy signal; and The first duty signal is received by a first of the plurality of slave conversion devices of the conversion devices coupled with the master conversion device, wherein the first of the slave conversion devices is based on the first Duty signal to control the output power of the first one of the slave conversion devices; The conversion devices are used to supply power to a load, and the master conversion device and the slave conversion devices communicate in a daisy chain manner. The power management method of the smart grid system according to claim 11, wherein the first one of the slave conversion devices provides a second duty signal according to the first duty signal. The power management method of the smart grid system as described in claim 12 further includes: The second duty signal is received by a second one of the slave conversion devices, wherein the second one of the slave conversion devices controls the second duty signal of the slave conversion devices according to the second duty signal The output power of the person. The power management method of the smart grid system according to claim 11, wherein the main control conversion device determines the flow direction of the total current according to the current measurement value, and the main control conversion device controls the flow direction according to the total current The main control converts the output power of the device and provides the first duty signal. The power management method of the smart grid system according to claim 14, wherein When the total current flows to the load, the main control conversion device increases the duty ratio of the first duty signal; When the total current does not flow to the load, the main control conversion device reduces the duty ratio of the first duty signal. The power management method of a smart grid system according to claim 15, wherein After increasing or decreasing the duty ratio of the first duty signal, the main control conversion device judges the flow direction of the total current again; When the total current flows to the load, the main control conversion device does not adjust the duty ratio of the first duty signal; When the total current does not flow to the load, the main control conversion device reduces the duty ratio of the first duty signal. The power management method of the smart grid system according to claim 12, wherein the main control conversion device controls the output power of the main control conversion device by determining whether the current measurement value is less than a current setting value and provides the second A duty signal. The power management method of a smart grid system according to claim 17, wherein When the current measurement value is less than the current setting value, the main control conversion device increases the duty ratio of the first duty signal; When the current measurement value is not less than the current setting value, the main control conversion device reduces the duty ratio of the first duty signal. The power management method of the smart grid system according to claim 18, wherein After increasing or decreasing the duty cycle of the first duty signal, the main control conversion device again determines whether the current measurement value is less than the current setting value; When the current measurement value is less than the current setting value, the main control conversion device does not adjust the duty ratio of the first duty signal; When the current measurement value is not less than the current setting value, the main control conversion device reduces the duty ratio of the first duty signal. The power management method of a smart grid system according to claim 17, wherein The first one of the slave conversion devices judges whether the duty cycle of the first duty signal decreases; When the duty cycle of the first duty signal decreases, the first of the slave conversion devices reduces the output power of the first of the slave conversion devices; When the duty cycle of the first duty signal does not decrease, the first of the slave conversion devices determines whether the output power of the first of the slave conversion devices reaches the first of the slave conversion devices的一 Maximum power of oneself; When the output power of the first of the slave conversion devices reaches the maximum power of its own, the first of the slave conversion devices does not adjust the output power of the first of the slave conversion devices; When the output power of the first of the slave conversion devices does not reach the maximum power of its own, the first of the slave conversion devices increases the output power of the first of the slave conversion devices.

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