SOLID STATE TRANSFORMER FOR ROAD LIGHTING SYSTEMS

Abstract

The invention relates to a solid-state transformer developed to replace conventional transformers in electrical boxes used in highway lighting systems. The invention comprises a 3-Phase Unit Power Factor Rectifier (1), DC-AC Inverter (2), Resonant Capacitor (3), High Frequency Transformer (4), AC-DC Rectifier (5), 3-Phase Inverter (6), and Controller (7). This structure enables control of the output voltage, improvement of the power factor, reduction of harmonics, electrical isolation between input and output, and monitoring and protection of the system. High-frequency operation results in a compact and energy-efficient structure.

Description

1 TARIFF SOLID STATE FOR ROAD LIGHTING SYSTEMS TRANSFORMER TECHNICAL FIELD The invention relates to power electronics, electrical energy conversion systems, and medium-low voltage. Energy used in power conversion technologies and road lighting infrastructure. The invention relates to the technical field of supply systems. Specifically, it concerns 10 systems located on highways. reliable, efficient and controllable supply of electrical energy to lighting fixtures solid-state transformer-based energy conversion aimed at providing this. This approach relates to the systems. This approach is applied to existing road electricity distribution infrastructures. can be used as a replacement for traditional grid frequency transformers The invention deals with an energy conversion structure based on power electronics. 15 inside highway electrical boxes used in highway lighting systems power electronics circuits that can be positioned and integrated with the network interface. It includes a transformer structure that operates at high frequency, along with the input voltage. by controlling and providing the desired output voltage, improving power quality, energy increasing its efficiency and delivering the same power at 20 GHz compared to traditional grid frequency transformers. For Highway Lighting Systems with more compact dimensions at this level It relates to Solid State Transformers. Within this scope, the invention encompasses active power electronics. It can regulate the output voltage through its control, in conjunction with the grid. capable of providing electrical isolation between loads, operating at a power factor close to unity. It can offer this characteristic thanks to its high-frequency transformer structure, volume and 25 Reduced weight, monitoring, protection and control functions within a single system. compact, bringing together components suitable for use in road lighting infrastructures. It relates to a solid-state transformer architecture. STATE OF THE ART 30 Highways require the transmission of electrical energy over long distances, and this Therefore, various technical difficulties arise in the implementation of energy distribution. 2 It is one of the infrastructure areas where lighting is located along the highway route. In order for the lighting fixtures to be powered by electrical energy, the energy must be transmitted along the way. They need to be moved. The length of the road and the lighting fixtures Considering that the voltage drops are distributed along the route... 5 in order to limit the number of people who want the lighting system to be properly powered. there is a need for transformer substations that perform voltage transformation at specific distances. It is heard. However, large-scale transformer buildings along the highway route establishment; in terms of land allocation, construction, infrastructure, maintenance and operation requirements 10 This constitutes a costly and difficult-to-implement solution. Therefore, the current In road lighting infrastructures, smaller transformer substations are used instead of large ones. It has a compact design and reduces the input voltage of approximately 1 kV to 0.4 kV. Highway Electrical Box systems convert the output voltage to a certain level. It is used. The Highway Electrical Box, hereinafter referred to as "KEK", is 15 It will be stated that the basic functional component of existing KEK systems is 1 kV / 0.4 Designed for kV input and output voltages, operating at mains frequency. It forms a conventional electromagnetic transformer. Conventional transformers used in current KEK systems are mainly input 20 and a constant conversion via electromagnetic coupling between the output windings. They are passive elements that provide the operating ratio. Therefore, these transformers operate in a way that... During this process, it is unable to actively and continuously control and regulate the output voltage. It is unable to do so. The voltage value at the transformer output is determined by the voltage fluctuations in the input voltage. from the changes that occur, even the voltage drops and the connected load 25 It can be affected by the level. This situation applies to areas along the highway route. lighting fixtures at the desired voltage level under different operating conditions and This makes it difficult for them to get a consistent diet. Another limitation of traditional transformers is their 30% effect on the power factor of the connected load. It has no regulatory effect. In road lighting systems. mercury vapor lamps or similar lamps used that have a reactive power requirement Reactive power drawn by lighting loads, conventional transformer 3 It is transferred from the primary side and thus to the network. This situation is the network increase in current, additional load on energy transmission elements and power of the system This can lead to a decrease in the factor. In order to reduce this effect... The use of reactive power compensation devices in existing systems This eliminates the need for additional hardware, connections, and maintenance outside of the KEK system. It is emerging. The transformer used in existing KEK systems is of a passive nature. due to the operating parameters of the system such as voltage, current, load and temperature an integrated audit structure that allows for direct evaluation 10 It is not present. Therefore, low or high input voltage, high current, and overcurrent are not possible. Detection of undesirable operating conditions such as overload and high temperature, The system can be deactivated when necessary, and operational information can be monitored remotely. Additional control, protection and independent of the transformer are required for transferring the signal to the point. Communication equipment is needed. 15 The traditional transformer was used during the day when the lighting fixtures were not working. Even during peak hours, it remains connected to the grid and powered. This situation... No-load losses also occur during periods when loads are not in operation. This causes the transformer in question to operate at 50 Hz 20 Hz. Operating at mains frequency, the transformer core and windings have the same power creating them in larger sizes compared to high-frequency structures of their value This requires traditional cakes and cakes, therefore volume and weight. in terms of creating a larger structure and along the highway route This makes it difficult to implement them compactly in limited settlement areas. 25 A search of the patent literature revealed that; Patent document number DE102020108105A1 describes the enhancement of electrical energy. a distribution system for distributing voltage over a transmission voltage 30 It is explained. In one of the alternative applications of the document, 400 V The input voltage at this level is increased to 1 kV using a step-up transformer. converting it to the level and that voltage to a power supply line 4 It is planned that the power will be transported over this route. Low-voltage consumers and lighting. For the purpose of supplying power to the luminaires, a transmission voltage of 1 kV is provided to the consumer. via step-down transformers located in nearby areas, 230 V or 400 V It is being reduced to the level of a parking lot or road. The document states that the infrastructure in question is a parking lot or road. 5 in the combined power supply of road lighting and electric vehicle charging stations. It is also explained that it can be used. However, the 1 kV alternating current application in document number DE102020108105A1, step-up and step-down transformers that operate primarily at the mains frequency It is based on the principle of placement at different distribution points. In the document, 10 consumer side voltage drop transformer conversion ratio or winding This is met by selecting the stages. In contrast, the three-phase input voltage It forms a regulated DC busbar by rectifying at a unit power factor. voltage conversion via high-frequency isolated LLC resonant converter a single 15 that performs this function and generates a three-phase controlled alternating voltage again at its output. A KEK solid-state transformer with a unit is not described. Furthermore, the power of the load... The active input stage prevents the factor from being reflected in the grid, thus preventing the system from being affected. where protection and monitoring functions are combined within the same power conversion unit. There is no structure. Document number CN203775473U describes intelligent road lighting systems. An energy-efficient control cabinet developed for use is described. The control cabinet in question is connected to the three-phase power transmission line, the power distribution system, and the energy system. energy saving device, current transformer, smart electricity meter, carrier communication The configuration includes a connection, a communication concentrator, and a remote terminal. This structure comprises 25 thanks to this, the voltage, current and energy consumed values ​​in the lighting line This allows for monitoring and remote control of road lighting. However, document number CN203775473U mentions monitoring and remote control. 30 functions are added to the existing energy distribution infrastructure via separate devices. This is being implemented. The document describes reducing the three-phase input voltage from 1 kV to 0.4 kV. a solid-state converter that converts to a controlled three-phase output voltage at the specified level It does not reveal the transformer. Similarly, an active transformer with a unit power factor. rectifier, regulated DC busbar, LLC resonant converter, high frequency isolation transformer and three-phase output inverter in a single power conversion The structure within which the unit is integrated is not described. Therefore, the aforementioned The control cabinet enhances the monitoring and control capabilities of existing systems. Passive voltage conversion of a conventional transformer, volume, no-load loss and power 5 This factor does not directly eliminate the problems. Patent document number US5943229A describes electrical distribution systems. A solid-state distribution transformer is described for use in this project. The system generally consists of an input stage, an isolation stage, and an output stage. It consists of stages. In the input stage, a high-voltage single-phase alternating current system is used. Input voltage can be converted to multiple isolated input modules via series-connected input modules. The unprocessed direct voltage is converted to a direct voltage; subsequently, each direct voltage is a separate In the isolation module, it is isolated via a high-frequency transformer. The outputs of the isolation modules are connected in parallel. The output level is 15. It converts the received low-voltage direct voltage into an alternating current output voltage. The document also states that the input current should be sinusoidal and in phase with the input voltage. Reducing the effect of load-induced harmonics and achieving a unitary power factor at the input. The aim is to provide this. Document number US5943229A describes a general-purpose solid-state distribution transformer. However, in their independent requirements, they demonstrate a high-voltage single-phase input. a modular architecture based on processing through multiple serial input modules It is based on the preferred output structure of the document: low voltage single-phase. It is geared towards an alternative output, and the three-phase output structure is only a possible change. 25 This is stated as follows. Furthermore, the direct voltage is high in the insulation stage. It is converted into a high-frequency square wave and transmitted through a transformer, and Soft-switching converters are mentioned among the possible alternatives; However, a DC-AC inverter, the magnetization and leakage of a high-frequency transformer 30 from a resonant capacitor interacting with its inductances and an AC-DC rectifier. The resulting LLC resonant transducer configuration is the primary solution. It is not explained. Most importantly, the structure in question is a 1 kV / 0.4 watt system used on highways. 6 A single-unit system with three-phase input and three-phase output, adapted to kV KEK infrastructure. It is not designed as a lighting power supply system. Patent document number EP2568589A1 describes an active AA-DA input stage. a multi-level converter 5 which includes a resonant DC-DC converter stage It is explained that the active input stage converts the alternating input voltage into an intermediate direct voltage. It converts; a DC-DC converter containing a resonant circuit and transformer. It converts the intermediate voltage in question into a direct output voltage. As stated in the document... A resonant circuit consists of a resonant inductor, a resonant capacitor, and a parallel circuit. It contains inductance. The control unit provides the output DC voltage, input voltage, and input 10V. By using the current, the input current is kept sinusoidal and controllable power is achieved. It aims to ensure that this factor is provided. However, the output of document EP2568589A1 is of the direct voltage type. and will supply lighting loads after the resonant converter output 15 An output inverter that produces a controlled three-phase alternating voltage is not described. The document describes series-connected active input stages and parallel-connected DC-DC. It is designed for a multi-level and modular structure that includes converter outputs. Additionally... The document describes a resonant DC-DC converter in open loop and at resonance frequency. It is operated at a corresponding fixed operating point. In contrast, application 20 In the structure in question, the high applied to the DC-AC inverter of the LLC resonant converter The converter gain and output are adjusted by changing the frequency switching signals. It is anticipated that the correct voltage will be checked during operation. This The document also mentions the KEK application specific to road lighting, approximately 1 kV. Three-phase input at level 25, three-phase output at 0.4 kV with low harmonics. obtaining and combining all protection and monitoring functions in the same unit. Its introduction is not explained. Patent document number US11152918B1 describes a three-phase system with a low modulation index. A solid-state transformer is described. In this design, a transformer has 30 The primary and secondary windings on the core are located on the primary side and the secondary side. It is connected to four-zone semiconductor switch groups. The switches are six control based on a repeated switching sequence consisting of different configurations 7 In each configuration, two of the three input phases are connected to the primary winding, and three are connected to the output winding. Two of the phases are connected to the secondary winding. High-frequency components. primary and secondary in order to limit the transfer of power to the grid or load LC filters are used on this side. However, document US11152918B1 directly concerns AA-AA conversion. four-zone switch groups and a specific six-step switching It is based on this configuration. In this structure, a three-phase AC-DC rectifier with a unit power factor is used. a regulated direct current busbar was created, followed by an isolated LLC. resonant DC-DC converter and the output of said converter is a three-phase 10V There is no separate output inverter that converts to alternating voltage. Therefore The topology in the document is the rectifier-LLC envisioned for the system in question. structurally and functionally from the resonant converter–output inverter sequence It is separated. Furthermore, the document in question states that the solid-state transformer is used for highway transport. Application to the KEK system included in the lighting infrastructure, the reactive power of the load is 15 regardless of its characteristics, operating at a power factor close to unity on the grid side. to provide or to control the unit when the lighting is not in operation. There is no specific regulation to stop its operation in this manner. When the patent documents described above are evaluated together; 1 kV 20 distribution systems that transmit energy at this level, to lighting lines monitoring and remote control cabinets for general purpose solid-state distribution transformers, resonant DC-DC converters, and direct three-phase AC- AA solid-state transformers exist separately under the known state of the art. It is observed that, however, within the scope of the investigation, highways 25 To be positioned within the KEK structure used in lighting systems; Regulates the three-phase input voltage by rectifying it to operate close to a unity power factor. an input rectifier that forms a DC bus, DC bus a DC-AC inverter that converts the voltage to high-frequency alternating voltage, high Resonance of the frequency transformer including magnetization and leakage inductances 30 a resonant capacitor formed by electrical isolation between input and output high-frequency transformer that provides voltage conversion, high frequency The AC-DC rectifier converts alternating voltage back to direct voltage, and the load and 8 three-phase with constant and low harmonics, independent of input voltage variations. the output inverter that generates the output voltage and the analog and digital operation of the system. Switching, monitoring, control and protection functions by reading the parameters. a controller that performs this function integrally within a single power conversion unit It is assessed that no technical solution has been described that brings them together in this way. 5 The system in question consists of an LLC resonant converter; a DC-AC inverter, and a resonant converter. capacitor, high-frequency transformer and AC-DC rectifier together It provides voltage conversion and electrical insulation through its operation; three-phase input. The rectifier and output inverter are 10, regardless of the electrical characteristics of the load. It allows for the monitoring of power quality on both the grid and load sides. Therefore, traditional KEK (Key Electronic Equipment) used in highway lighting systems Output voltage variations resulting from the passive nature of transformers, reactive transferring power demand to the grid, need for additional compensation, limited monitoring and 15 Protection capability, no-load losses due to continuous energization, and 50 Hz operation. It will address the high volume and weight issues arising from its frequency; the same voltage transformation over time, power factor correction, harmonic limiting, Galvanic isolation, output voltage regulation, monitoring, protection, and controlled operation. Highways 20 will provide its functions within a single, compact structure. Solid-state transformers are required for lighting systems. DEFINITION OF INVENTION This invention eliminates the disadvantages described in the prior art. 25 It removes and provides solutions to current needs. The invention; Highway Electrical Boxes used in highway lighting systems. instead of traditional grid frequency transformers located within the (KEK) a power electronics-based solid-state transformer developed for use in 30 It includes the invention that saves energy for road lighting fixtures. its power supply is a passive transformer that only performs voltage conversion. not only through, but also through voltage regulation, power quality improvement, 9 an integrated energy system that can also perform monitoring, protection and control functions. This is carried out through the conversion system. The solid-state transformer used in this invention is a high-frequency power transformer. Thanks to its electronics-based structure, it is 5 times better than traditional mains frequency transformers. They can be manufactured in more compact sizes, and at the same power level. They can be produced with low volume and weight, and are electrical boxes used on highways. It can be integrated more effectively. In addition, active control... Thanks to its structure, it is independent of changes in input voltage or load conditions. In this way, it is possible to keep the output voltage at the desired level. 10 With this invention, the power factor is improved on the grid side, and harmonic distortion is reduced. is reduced and high power is supplied from the grid regardless of load characteristics. This ensures a current draw of sufficient quality. Thus, the needs of existing systems are met. The need for additional reactive power compensation is reduced, and energy distribution 15 This contributes to the more efficient operation of the infrastructure. The system developed within the scope of the invention provides input thanks to its active power electronics infrastructure. continuous monitoring of operating parameters such as voltage, output voltage, current, temperature, etc. This allows for monitoring. Overcurrent, overload, 20 through the same structure. protection functions against operating conditions such as low or high voltage This can be achieved, and system reliability is significantly increased. Furthermore, The ability to transfer the collected operational data to remote monitoring and control systems. This simplifies maintenance and operation processes. The main advantages offered by the invention are summarized below. Continuous regulation of the output voltage. Thanks to its active control structure, a solid-state transformer can control voltage or load fluctuations. Regardless of changes in conditions, the output voltage can be maintained at the desired level of 30. It is able to hold. In addition, the output inverter in the system is based on the characteristics of the load. independently of any time, high quality, with very low harmonic components. It produces sinusoidal voltages. Thus, road lighting fixtures are more efficient. They are provided with stable and reliable nutrition. Improving Power Quality The invention increases the power factor of the current drawn from the grid and reduces harmonics. The components are being reduced. As a result, the reactive power load on the grid decreases. Energy levels are being reduced and the quality of energy transmission is being improved. Compact Structure Provides Thanks to its high-frequency transformer structure, it can produce 10 transformers of the same power rating. Smaller in size and more efficient than traditional grid frequency transformers. A lightweight system is obtained. Thus, additional features are added within existing CEC structures. Ease of use is provided without requiring structural changes. Increasing Energy Efficiency 15 Since the system can only be activated when needed, the lighting... unnecessary energy losses that occur when the system is not in operation is reduced. In addition, energy conversion efficiency is improved thanks to the power electronics-based structure. By increasing [the amount], a contribution is made to reducing operating costs. Offering both monitoring and protection functions. The system developed within the scope of this invention does not require any additional control units. We can continuously monitor operating parameters without noticing and provide protection when necessary. It can activate its functions. This increases system reliability. Maintenance processes are also simplified. 25 Ensuring Compatibility with Smart Grid Applications Thanks to the active and controllable nature of the solid-state transformer, remote monitoring is possible. remote control and future smart grid functions It is possible to integrate it into the system, thus providing highway lighting. 30 enable its infrastructure to work in compatibility with digital energy management systems. is provided. 11 REFERENCE LIST 1. 3-Phase Unit Power Factor Rectifier 2. DC-Automated Converter 3. Resonance Capacitor 5 4. High-Frequency Transformer 5. AA-DA Rectifier 6. 3-Phase Inverter 7. Controller 8. 3-Phase Network 10 9. Load 10. Control and Feedback Connection 11. Grounding Connection AA: Alternating current DA: Direct current 15 V_R: R phase voltage V_S: S phase voltage V_T: T phase voltage n: Network neutral point Lg: Inlet filter inductance 20 Cf1: First DC bus capacitor Cr: Resonance capacitor Lr: Resonance inductance Lm: Magnetizing inductance 1:n: Transformer winding ratio 25 Cf2: Second DC bus capacitor Lo: Output filter inductance Co: Output filter capacitor N: Output neutral point BRIEF DESCRIPTION OF THE DRAWINGS Figure 1: Representative overview of the invention. 12 EXPLANATION OF THE INVENTION For the purpose of defining this invention, any effect that limits the scope of protection. Without creating it, the following explanations are representative of the application shown in Figure 1. 5 It was done through. The invention provides electrical energy to lighting fixtures used on highways. A single-unit solid-state unit positioned between the 3-Phase Network (8) and the Load (9) This relates to the transformer. The solid-state transformer in question is a 3-phase unit power transformer with a capacity of 10 volts. Factor Rectifier (1), DC-AC Inverter (2), Resonance Capacitor (3), High Frequency Transformer (4), AC-DC Rectifier (5), 3-Phase Inverter (6) and Controller (7) includes. Components that perform power conversion with the controller (7). Data and command transfer between them Control and Feedback Link (10) It is provided via. 15 The solid-state transformer described in this invention is used in highway lighting systems. and converts the input voltage of approximately 1 kV to an output voltage of 0.4 kV. Suitable for use in electrical boxes on highways that convert It has been developed. In the sample application of the invention, the system is powered by a 3-Phase Network (8) 20 with the supplied AC voltage of nominal 1000 V and 50 Hz It operates. The voltage, at a nominal level of 1000 V, transmits electrical energy to the highway. economic considerations may arise from the voltage drop that may occur during transmission. in order to limit it in this way, higher than the standard 400 V voltage level It is preferred as follows. 25 3-Phase Network (8), R, S and T phases which have a phase difference with respect to each other It includes the voltage for phase R, called R Phase Voltage (V_R), and the voltage for phase S, called S Phase Voltage. The voltage of phase T is shown as (V_S) and the voltage of phase T is shown as T Phase Voltage (V_T). 3 The neutral connection on the Multi-Phase Network (8) side is expressed as Network Neutral Point (n) 30 The Network Neutral Point (n) is connected to the ground via the Grounding Connection (11). It is linked to its potential. 13 Between the 3-Phase Network (8) and the 3-Phase Unit Power Factor Rectifier (1), each There is an Input Filter Inductance (Lg) on ​​each phase line. Input Filter Inductance (Lg) in 3-Phase Unit Power Factor Rectifier (1) due to the high-frequency switching operations performed, the input current 5 high-frequency harmonic components that may occur on the 3-Phase Network (8) side It limits the transmission. The Input Filter Inductance (Lg) is thus 3-Phase. Contribution to improving the waveform of the current drawn from the grid (8) It provides. Alternating Current (AC) voltage supplied by 3-Phase Network (8), Input Filter 10 To 3-Phase Unit Power Factor Rectifier via Inductance (Lg) (1) It is transferred. 3-Phase Unit Power Factor Rectifier (1), applied to its input. It converts alternating current (AC) voltage to direct current (DC) voltage. 3-phase. Basic functions of the Unit Power Factor Rectifier (1); Alternating Current (AC) voltage and Converting the current into Direct Current (DC) voltage and current, resulting in 15 To maintain the obtained Direct Current (DC) bus voltage at the desired value and for 3-phase The purpose is to check the power quality of the current drawn from the grid (8). 3-Phase Unit Power Factor Rectifier (1) is actively used as the mains interface. It is being checked. In this context, 3-Phase Unit Power Factor Rectifier (1), 3 20 The current drawn from the multi-phase network (8) should be in the form of a sinusoidal wave. limiting harmonic components in the current and total harmonics It ensures that the distortion is kept below the specified limits. 3-Phase Unit Power The Multi-Fraction Rectifier (1) is mainly operated at unit power factor and is 3-Phase The power factor seen by the grid (8) is 1 or close to 1, e.g. 25 This allows it to be kept at approximately 0.99. If needed... In this case, a 3-phase unit power factor rectifier (1) takes a reactive power given to it. It can also be checked by following its reference. The conversion and control of the 3-Phase Unit Power Factor Rectifier (1) 30 to perform its operations, it has semiconductor power switches in its structure Appropriate switching signals are applied. In the example application of the invention, 3 The three-phase unit power factor rectifier (1) semiconductor power switches silicon 14 They are designed as carbide-based power switches. The switching in question... The signals are generated by the Controller (7) and Control and Feedback To the 3-Phase Unit Power Factor Rectifier (1) via its connection (10) is being transferred. First DC Bus at the output of the 3-Phase Unit Power Factor Rectifier (1) It has a capacitor (Cf1). The first DC bus capacitor (Cf1) is 3-phase. Direct Current (DC) bus generated by Unit Power Factor Rectifier (1) may occur due to high-frequency switching in the voltage It filters voltage fluctuations. The first DC bus capacitor (Cf1) filters these 10 thanks to the DC-AC Inverter (2) with a more stable DC bus voltage It enables them to be nourished. The Direct Current (DC) bus is supplied through the first DC bus capacitor (Cf1). The voltage is applied to the input of the DC-AC Inverter (2). DC-AC Inverter (2) is 3-Phase 15 As a result of the rectification and regulation processes of the Unit Power Factor Rectifier (1) The obtained DC bus voltage is used in the High Frequency Transformer (4) suitable high-frequency alternating current (AC) voltage for its operation It transforms. The alternating current (AC) voltage produced by the DA-AA inverter (2) is mainly It is high frequency and square wave in form. DC-AC Inverter (2), the system's operation the high-frequency alternating current (AC) voltage it produces depending on its requirements It can change the frequency. Control of the output frequency of the DA-AA Inverter (2) With this, the energy transferred to the High Frequency Transformer (4) side is AC-DC 25 The Direct Current (DC) voltage obtained at the output of the rectifier (5) is checked. is being done. DC-AC Inverter (2), Resonance Capacitor (3), High Frequency Transformer (4) and AA-DA Rectifier (5) together form the LLC resonant converter. (30) The subject is the LLC resonant converter, which converts the Direct Current (DC) voltage applied to its input. by changing its level and transferring it to its output, High Frequency Transformer (4) It provides electrical isolation between the input and output. Resonance Capacitor (3), with the symbol Resonance Capacitor (Cr) in Figure 1. It is shown. Resonance Capacitor (3), High Frequency Transformer (4) Resonance inductance (Lr) and magnetization inductance (Lm) together with resonance It forms the circuit. Resonance Capacitor (Cr), Resonance 5 The interaction between inductance (Lr) and magnetization inductance (Lm) is called LLC. operating characteristics of the resonant converter and voltage conversion gain It determines. Resonance Inductance (Lr), Leakage of High Frequency Transformer (4) 10 It refers to resonance inductance related to magnetization. Inductance (Lm) of the High Frequency Transformer (4) is magnetization It expresses the inductance depending on its characteristic. Resonant Capacitor (Cr), Resonance Inductance (Lr) and Magnetization Inductance (Lm) of the DC-AC Inverter (2) working together under the applied high-frequency alternating current (AC) voltage, 15 LLC handles the energy transfer for the resonant converter. High Frequency Transformer (4) formed by DC-AC Inverter (2) It takes a high-frequency alternating current (AC) voltage as its input and the said The alternating current (AC) voltage is 20 in proportion to the transformer winding ratio (1:n). It transfers the voltage to the secondary side. High Frequency Transformer (4), voltage as well as the conversion of the level with the input side of the solid-state transformer It provides electrical insulation between the output and output sides. Transformer Winding Ratio (1:n), Primary of High Frequency Transformer (4) 25 It describes the relationship between the number of bandages and the number of secondary bandages. Transformer Winding Ratio (1:n), Production of High Frequency Transformer (4) is determined during the production of the High Frequency Transformer (4) It cannot be changed afterwards. High transformer winding ratio (1:n) Input and output voltage differences can be obtained efficiently. 30 The operating frequency of the High Frequency Transformer (4) is the conventional grid Its high frequency compared to other transformers is the characteristic of High Frequency Transformers. 16 (4) allows it to be created in smaller sizes for the same power rating. In the sample application of the invention, the High Frequency Transformer (4) operates at approximately 50 kHz It has a working frequency. Thanks to this, the High Frequency Transformer (4) Its volume and weight are being reduced and it is being used inside highway electrical boxes. A suitable compact structure is obtained. 5 The conversion between input voltage and output voltage of the LLC resonant converter. Earnings are determined primarily by two separate factors. The first of these is High The transformer winding ratio (1:n) of the frequency transformer (4) 10 created and remaining constant after the production of the High Frequency Transformer (4) The second is the voltage conversion ratio. The second is the high applied to the DC-AC Inverter (2). frequency switching signals that can be changed during operation conversion profit. 15 obtained by changing the switching frequency of the DA-AA Inverter (2) Conversion gain; Resonance Capacitor (Cr), Resonance Inductance It is affected by the values ​​of magnetization inductance (Lr) and magnetization inductance (Lm). Controller (7) to DC-DC Inverter via Control and Feedback Link (10) (2) LLC resonance by controlling the applied switching signals The desired 20 DC voltage is obtained as the Direct Current (DC) voltage at the output of the converter. It ensures that the High Frequency Transformer (4) is kept at the level. Variable DC-AC Inverter (2) with fixed Transformer Winding Ratio (1:n) Voltage transformation is achieved by using switching control in conjunction with other methods. The high 25 obtained on the secondary side of the High Frequency Transformer (4) Alternating Current (AC) voltage with frequency is fed into the input of the AC-DC Rectifier (5). It is applied. AA-DA Rectifier (5), High Frequency Transformer (4) Converts the high-frequency alternating current (AC) voltage provided by the DC voltage. It converts to (DA) voltage. Obtained by AC-DA Rectifier (5) The Direct Current (DC) voltage is then 30 in the supply of the 3-Phase Inverter (6). It is used. 17 Second DC Bus Capacitor (Cf2) at the output of the AA-DA Rectifier (5) It is located. Second DC Bus Capacitor (Cf2), AC-DC Rectifier (5) fluctuations in the Direct Current (DC) bus voltage created by filtering and providing a more stable Direct Current (DC) voltage to the 3-Phase Inverter (6) It provides nutrition. 5 The Direct Current (DC) voltage supplied through the second DC Bus Capacitor (Cf2), It is applied to the input of the 3-Phase Inverter (6). The 3-Phase Inverter (6) is the said Direct The current (DC) voltage is three-phase alternating current (AC) suitable for supplying the load (9). It converts the 3-Phase Inverter (6) into a semiconductor power of 10 in its structure. three-phase and sinusoidal via switching signals applied to their switches It generates output voltages in waveform form. Switching signals applied to the 3-Phase Inverter (6) are controlled by the Controller (7). It is determined and 15 to the 3-Phase Inverter via Control and Feedback Connection (10). (6) is transmitted. The controller (7) receives feedback regarding the output voltage of the 3-Phase Inverter (6). By evaluating the supply data, it is determined whether there is a problem under Load (9) or in the 3-Phase Network (8). It maintains the output voltage at the desired value regardless of incoming changes. At the output of the 3-Phase Inverter (6), the Output Filter Inductance (Lo) on each phase line is 20 Output Filter Inductance (Lo) is located in the high frequency of the 3-Phase Inverter (6). high-frequency components that may occur in the output current due to switching It restricts. The 3-Phase Inverter (6) also has an Output Filter Capacitor (Co) at its output. 25 The output filter capacitor (Co), together with the output filter inductance (Lo), forms the output filter. It consists of the Output Filter Inductance (Lo) and Output Filter Capacitor (Co). Thanks to this, the output of the 3-Phase Inverter (6) has a low harmonic component and sinusoidal An alternating current (AC) voltage with the given waveform is obtained. Output Filter Capacitors (Co) are located between the phase outputs and the Output Neutral Point (N). It is connected. Output Neutral Point (N) is the neutral at the output of the 3-Phase Inverter (6). to form the connection and the phase-neutral voltage of the Load (9) according to the connection structure 18 This structure allows the use of a 3-phase inverter (6), single-phase inverter. or three-phase load (9) high quality and low harmonic component alternating current It can be powered by (AA) voltage. Load (9), one or more lights included in the highway lighting system 5 It refers to the luminaire. The load (9) draws nonlinear current or If there is a reactive power requirement, the electrical specifications in question are 3-phase. The effect on the network (8) with 3-Phase Unit Power Factor Rectifier (1) It is limited by the inverter (6). 3-Phase Inverter (6), the type of Load (9) and Regardless of the operating conditions, the load (9) has a constant value and low harmonics 10 It provides a component output voltage. Even if the power factor or current waveform of the load (9) changes, 3-Phase Unit Power Factor Rectifier (1) outputs a sinusoidal waveform through the 3-phase network (8), low It draws current with harmonic components and a power factor close to unity. Thus, the load is 15 (9) direct 3-Phase reactive power demand and nonlinear current characteristic Transfer to the network (8) is prevented. Thanks to this structure, in the existing systems the need for additional reactive power compensation systems is being reduced. The controller (7) controls all active power conversions in the solid-state transformer. It controls the components. Controller (7), 3 Phase Unit Power Factor Rectifier (1), DC-AC Inverter (2), AC-DC Rectifier (5) and 3-Phase Inverter Analog and digital data related to (6) Control and Feedback Link (10) It receives it through. The controller (7) evaluates the feedback data it receives and 25 It generates the switching signals that will be applied to the relevant power conversion components. Control and Feedback Link (10), Controller (7) with solid state bidirectional data and control between the power conversion stages of the transformer. It provides the transfer. The voltage and current obtained from the power conversion stages are 30. Operational information such as load and temperature Control and Feedback Link (10) is transferred to the Controller (7) via; created by the Controller (7) 19 Switching, control and stop signals are also included in the Control and Feedback Link. Power is transmitted to the relevant power conversion components via (10). The controller (7) sets the input voltage of the 3-phase network (8) to 3-phase unit power factor. The input and output values ​​of the rectifier (1), the operating status of the DC-AC inverter (2), 5 Output values ​​of the AC-DC Rectifier (5), output voltage of the 3-Phase Inverter (6) and It monitors the operating conditions of the load (9). Read by the controller (7). Operating parameters can be transferred to a monitoring point when needed. Thus... The operating status of the solid-state transformer can be monitored remotely, and Data regarding the operation of the highway lighting system 10 can be evaluated. The controller (7) detects when the operating parameters go outside the normal operating ranges. In this case, it activates the protection functions. Within this scope, low input voltage, high input voltage, high current, overload and high temperature 15 When one or more of these conditions are detected, the Controller (7), Control and Feedback Operation of the relevant power conversion components via the Supply Connection (10) It limits or stops the system. Thus, 3-Phase Unit Power Factor. Rectifier (1), DC-AC Inverter (2), High Frequency Transformer (4), AC-DC Rectifier (5), 3-Phase Inverter (6) and Load (9) against undesirable operating conditions 20 It is protected. The active and Supervisor (7) controlled structure of the system, solid state transformer to be operated only during the time intervals when lighting energy is needed It allows. When the load (9) is not in operation, especially the road lighting 25 The system can be shut down during daytime hours when it is not in use. thanks to the continuous power supply of traditional grid frequency transformers. Idle time losses resulting from downtime are reduced. In the solid-state transformer that is the subject of the invention, energy conversion is from a 3-phase network (8) 30 Starting with Input Filter Inductance (Lg), 3-Phase Unit Power Factor Rectifier (1), First DC Bus Capacitor (Cf1), DC-AC Inverter (2), Resonance Capacitor (3), High Frequency Transformer (4), AC-DC Rectifier (5), Second DC Bus Capacitor (Cf2), 3-Phase Inverter (6), Output Filter Inductance (Lo) and The output is made through the Filter Capacitor (Co) to the Load (9). During this conversion, R Phase Voltage (V_R), S Phase Voltage (V_S) and T Phase Voltage Three-phase AC (AC) input voltages in the form (V_T) are primarily 3-Phase Unit 5 Direct Current (DC) busbar regulated by Power Factor Rectifier (1) It is converted into voltage. The aforementioned Direct Current (DC) bus voltage is DC-AC. It is converted to high frequency Alternating Current (AC) voltage by the inverter (2), Resonance Capacitor (Cr), Resonance Inductance (Lr), and Magnetization It is transferred to the High Frequency Transformer (4) via its inductance (Lm). 10 High Frequency Transformer (4), Transformer Winding Ratio (1:n) voltage transformation and input-output insulation accordingly It performs. On the secondary side of the High Frequency Transformer (4) High frequency AC voltage is converted to 15 AC-DC by AC-DC Rectifier (5) It is converted to Direct Current (DC) voltage and by the 3-Phase Inverter (6) It is converted back to three-phase alternating current (AC) voltage. Output Filter Three-phase inductance (Lo) filtered by the output filter capacitor (Co). Alternating Current (AC) voltage to Load (9) together with Output Neutral Point (N) is being implemented. 20 The invention is realized through the active power electronics structure and Controller (7). Through its control, it enables regulation of the output voltage, reactive power compensation, and power... Improving quality, monitoring and protecting operating parameters It is possible to perform its functions. Appropriate control 25 By applying approaches to the Controller (7) the voltage stability support, integration of distributed generation systems into the system, energy storage integration of systems into the system and additional support for the 3-Phase Network (8) The implementation of functions also becomes possible. As a result, the solid-state transformer that is the subject of the invention is powered by a 3-phase network (8). It improves the power factor of the drawn current, and limits harmonic components, The reactive and nonlinear character of the load (9) on the 3-Phase Network (8) 21 reducing its effect, the load (9) independently of input voltage and load variations feeding with regulated voltage, thanks to High Frequency Transformer (4) It provides electrical insulation and monitoring, control and via the Controller (7). It performs its protection functions within a single unit. High Frequency Thanks to the high operating frequency of the transformer (4), 5 with the same power value Size and weight are reduced compared to grid frequency transformers; energy high efficiency, improved power quality and in highway electrical boxes A compact structure suitable for use is obtained.

Claims

22 REQUESTS 1. This invention is a solid-state transformer for highway lighting systems. and its feature is; 5 • Converts three-phase AC (AC) input voltage to regulated DC (Direct Current). (DC) converts the current drawn from the grid to bus voltage and the unit power of that current. ensuring that the power factor is at or close to unit power factor 3-Phase Unit Power Factor Rectifier (1), 10 • Direct Current at the output of the 3-Phase Unit Power Factor Rectifier (1) (DA) converts the bus voltage to high-frequency alternating current (AC) voltage. Converting DA-AA Inverter (2), • Output of the DA-AA Inverter (2) and the High Frequency Transformer (4) located between the primary side and the High Frequency Transformer (4) 15 by interacting with their inductances, they provide resonant energy conversion. Resonance Capacitor (3), • High frequency Alternating Current (AC) produced by DA-AA Inverter (2) converts the voltage depending on the winding ratio and connects the input and output. High Frequency Transformer (4) providing electrical insulation, 20 • Obtained on the secondary side of the High Frequency Transformer (4) converts high-frequency alternating current (AC) voltage to direct current (DC). AC-DC Rectifier (5) which converts voltage, • The DC voltage at the output of the AC-DC Rectifier (5) is three-phase. and a 3-phase 25 that converts it to sinusoidal alternating current (AC) output voltage. Inverter (6) and • 3-Phase Unit that reads analog and digital data related to system components. For Power Factor Rectifier (1), DC-AC Inverter (2) and 3 Phase Inverter (6) generating switching signals and controlling and protecting the system Controller (7) 30 which performs its functions It includes. 23 2. Solid state for the highway lighting systems mentioned in Claim 1. It is a transformer and its feature is; 3-Phase Unit Power Factor Rectifier (1) At its input, it contains an Input Filter Inductance (Lg) connected in series with each phase line.

3. Solid state 5 for the highway lighting systems mentioned in Claim 1. It is a transformer and its feature is; 3-Phase Unit Power Factor Rectifier (1) It contains a first DC bus capacitor (Cf1) at its output.

4. Solid state for the highway lighting systems mentioned in Claim 1. It is a transformer and its feature is; 3-Phase Unit Power Factor Rectifier (1) 10 semiconductor power supply consisting of silicon carbide (SiC) MOSFETs in its structure It contains the keys.

5. Solid state for the highway lighting systems mentioned in Claim 1. It is a transformer and its feature is; Resonance Capacitor (3), Resonance 15 LLC is formed by the inductance (Lr) and magnetization inductance (Lm). It contains a resonant circuit.

6. Solid state for the highway lighting systems mentioned in Claim 5. It is a transformer and its feature is; the switching frequency of the DC-AC Inverter (2) is 20 By changing the conversion gain and output of the LLC resonant circuit, the correct value is achieved. It includes a frequency control structure that adjusts the current (DC) voltage.

7. Solid state for the highway lighting systems mentioned in Claim 1. It is a transformer, and its characteristic feature is that it has a 25mm gap between its primary and secondary windings. The transformer has a winding ratio of (1:n) and an operating frequency of approximately 50 kHz. It contains a High Frequency Transformer (4).

8. Solid state for the highway lighting systems mentioned in Claim 1. It is a transformer and its feature is; Second DC 30 at the output of the AC-DC Rectifier (5). It contains a bus capacitor (Cf2). 24 9. Solid state for the highway lighting systems mentioned in Claim 1. It is a transformer and its feature is that each phase at the output of the 3-Phase Inverter (6) Output Filter Inductance (Lo) and phase outputs on the line and Output Neutral Point (N) It includes interconnected Output Filter Capacitors (Co).

10. Solid state for the highway lighting systems mentioned in Claim 1. It is a transformer and its feature is; Controller (7) and power conversion components Control and Feedback provides bidirectional data and control transfer between them. It contains the link (10). 15

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