A current regulator circuit that provides a smooth and programmable current to loads with variable electrical resistance.
Patent Information
- Application Number
- TR202615863
- Authority / Receiving Office
- TR · TR
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2026-09-16
- Publication Date
- 2026-09-21
Smart Images
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Abstract
Description
1 TARIFF SMOOTH AND UNIFORM TRANSFER TO LOADS WITH VARIABLE ELECTRICAL RESISTANCE. A current regulator circuit providing programmable current. TECHNICAL FIELD The invention allows for the programmability of the current flowing through loads with variable electrical resistance. its arrangement in a closed loop according to a reference current and the loads in question It relates to a current regulator circuit that makes it possible to provide a smooth and continuous current. 10 PREVIOUS TECHNIQUE Today, precise and programmable control of high currents is possible; Joule heating applications, electrochemical processes, plasma sources, high-power LED 15 drivers, battery charging and discharging test devices, thermally or electromagnetically a fundamental element in a wide variety of engineering applications, including the devices being operated This creates a requirement. In these applications, the current passing through the load, the load changes that may occur in impedance or supply voltage over time as independent as possible from changes, a fixed or time-varying 20 It is expected to precisely track the reference current. The predicted load current. Deviation from the value, the electrical power transferred to the load and the resulting thermal output, It causes a change in chemical, optical, or electromagnetic effects. Particularly in Joule heating applications, where electrical energy is converted into heat energy, 25 Precise regulation of the current flowing through the load is important. In the load The heat produced depends on the electrical resistance of the load and the current flowing through the load. It varies. However, the electrical resistance of the charge depends on temperature, material properties, This may vary depending on working conditions or time. In this case, in advance... Applying a specified voltage or a constant driving signal to the load, each operation 30 obtaining the same current and therefore the same heating behavior under these conditions It is unable to provide this. Shape memory alloys are produced by heating with Joules and using a current... 35 is a prime example of a load that needs to be precisely regulated. Shape memory alloys undergo phase transformation depending on temperature changes. It carries out and as a result of the phase transformation in question, takes on a predetermined form. 2 It exhibits the ability to generate rotational or mechanical movement. Shape memory alloys the characteristic shape memory effect occurs in a controlled manner in order for this to happen, the thermal energy transferred to the alloy, and therefore the energy passed through the alloy... The Joule heating current needs to be precisely controlled. The electrical resistance of shape memory alloys does not remain constant; it depends on the temperature of the alloy and the materials within it. the phase it is in, its austenitic or martensitic transformation history, the progression of the phase transformation It varies non-linearly depending on the level and working conditions. Also, differences in material properties, repeated operating cycles, and aging can affect performance. Factors can also cause changes in electrical resistance. Therefore, 10 Applying a constant stress to a shape memory alloy causes different temperatures, phases, and phase transformations. This can lead to different current values depending on past conditions. The current... It is sufficient for Joule heating and phase transformation to remain lower than predicted. If it cannot be realized, or if it is higher than expected, it leads to overheating, phase making it more difficult to control the transformation, reducing the accuracy of control, or 15 This can lead to damage to the material. In the current state of the art, open-loop driving is used to generate the load current. approaches, fixed resistance networks and unregulated linear power supplies It is used. In open-loop approaches, the control value determined for driving the load is 20. It is implemented without using feedback regarding the actual load current. Therefore deviation of load resistance or supply voltage from initially accepted values In this case, the actual load current also deviates from the desired value. Fixed resistance networks, however, allow the current to... while contributing to its limitation under certain conditions, it also contributes to varying load resistance. and is unable to adapt effectively to feeding conditions. 25 Unregulated linear power supplies also cause the load current to exceed the supply voltage. This can cause it to be affected by changes in the electrical resistance of the load depending on temperature. or in applications where it varies depending on the phase, only the supply voltage needs to be determined, 30 is sufficient for precise and repeatable control of the current flowing through the load. This is not the case. In such arrangements, a different current level or current profile is required. This requires replacing circuit components and readjusting the power supply. or the use of an external control system may be required. Therefore, an open-loop and Approaches based on fixed hardware values, programmable and time-dependent current. Their application is limited. 35 3 In the current state of the art, the aim is to enable the excitation of loads with stable direct current. High current capacity laboratory-type power supplies are also used. For example, see figure Memory alloy torsion spring actuators, from a stabilized current source It is known to be driven by current pulses of 5 A. This type of laboratory-type power supplies, characterization of shape memory alloys and 5 at specific operating points It can be suitable for testing purposes. However, most loads are handled manually. This is stimulated by current levels that are configured or triggered externally. integrating solutions into embedded systems and flexibly through software. This makes programming difficult. Laboratory power supplies also differ in physical size, cost, and system integration. Suitable for use in compact actuator or robotic systems in terms of requirements. This may not be the case. A real-time current profile that changes over time. When this is required, the power supply can also have a programmable interface or a top-down system. It may be necessary to have a level control unit. Multiple figures 15 memory alloy elements that need to be operated independently In applications, a separate power supply for each channel or additional multi-channel driving is required. This may require additional hardware, which increases system complexity and cost. In the current state of the art, high-current 20V is used to drive shape-memory alloy wires. Specialized constant current source circuits based on power operational amplifiers are also being developed. In this context, multi-channel current devices based on the OPA549, capable of providing current in the amperage range, are available. The use of drivers is known. These circuits directly transfer the load current. It provides a suitable solution for organizing and testing shape memory alloys. However, these regulations apply to high-current power operational amplifiers. due to dependence and losses occurring in power elements, careful thermal analysis is necessary. It requires management. Power operational amplifier-based solutions, applicable current and voltage ranges. This depends on the electrical and thermal limits of the amplifier used. 30 In applications requiring high current, the cost, accessibility, and availability of these components are important considerations. Cooling requirements can complicate system design. Also, MATLAB / Simulink or the creation of desired current profiles through another external control medium and When necessary, these solutions can be implemented in embedded and standalone systems. The flexibility in its adaptation may decrease. 35 4 In the current state of the art, they are compact and operate in an energy-efficient manner. due to MOSFET-based pulse width modulation (PWM) Power layers are widely used, especially in robotics based on shape memory alloys. In actuator systems, power MOSFETs operate between cutoff and conduction states. Switched at high frequency and the average power transferred to the load is the PWM signal task 5 The cycle is adjusted by changing it. In this approach, the power element is largely controlled. Keeping it in a completely closed or low-loss transmission state reduces power loss and improves cooling. It contributes to reducing the need. However, in PWM-based power stages, the current supplied to the load is directly and continuously 10⁻¹⁰ Instead of being regulated as a current value, it is indirectly regulated by the duty cycle. It is related to changes in the electrical resistance of the load or the supply voltage. If this deviation occurs, the same duty cycle will cause different load currents to occur. This is possible, especially since electrical resistance depends on temperature and phase transformation. In shape memory alloys, the duty cycle varies with the actual Joule heating current of 15. This leads to a change in the relationship between them during the study. The use of PWM also creates discrete switching transitions in the load current, and current fluctuations at the switching frequency and its harmonics It creates a highly nonlinear pattern in current-sensitive loads. or in materials with temperature-dependent electrical resistance and in safety or process In applications where sudden current changes must be avoided due to quality concerns Fluctuations in this area can lead to undesirable consequences. Switching-related issues. While an output filter can be used to reduce the number of components, the filtering process requires additional effort. Circuit components create physical volume and cost; moreover, even after filtering, 25 Current fluctuations can now be detected. Rapid voltage and current fluctuations during PWM-based driving cause electromagnetic interference. This can cause problems and make current measurement difficult. The presence of switching components at the output of the current sensor means the measurement signal is 30. This may require filtering or determining appropriate sampling times. The requirements lead to increased complexity in the control algorithm and hardware architecture. This is especially true in applications where a smooth and continuous current waveform is required. This reduces the suitability of the PWM approach. 35 Furthermore, in PWM-based driving methods, the current is averaged over the duty cycle. This involves organizing the system in such a way that it directly tracks rapidly and constantly changing current references. In terms of closed-loop current control, the power element is operated in the linear region. Compared to their structures, they can create some limitations. Duty cycle and actual load current The relationship between them varies depending on the load resistance and supply conditions, more Additional measurement and filtering during the application of comprehensive and dynamic control algorithms. and may necessitate compensation processes. This situation applies to PWM-based 5 Integration of sliding structures with high-level control algorithms It can make things more difficult. In the current state of the art, the properties of shape memory alloys are based on their electrical resistance. To improve self-sensing performance, constant current heating modules are also available. It is used. In these applications, the use of current feedback allows the alloy to... more reliable assessment of the electrical condition and load resistance This contributes to reducing the impact of changes on driving behavior. The subject of these studies is the measurement of the actual load current in the control of shape memory alloys. and highlights the importance of including it in the feedback loop. 15 However, conventional constant current heating modules offer different and time-dependent currents. Direct programming of profiles via external software, at high current levels. Creating a compact power stage, monitoring variable resistive loads in a closed loop. 20 requirements for ensuring and avoiding switching-related fluctuations It may not be able to meet all the requirements simultaneously. Especially when it senses the actual load current, continuously processes the difference between the detected current and the programmable reference current, and an integrated system that precisely adjusts the load current according to this difference. Solutions are needed. In closed-loop current control, using only proportional feedback allows the load to... Because it has a non-zero electrical resistance, the measured current and the desired current are different. This can cause a steady-state fault to remain between the reference current and the load. its resistance to temperature, Joule self-heating, phase transformation, material changes or aging The deviation due to this, the steady-state error in question, different operation 30 This can lead to changes in the conditions. Therefore, by providing cumulative adjustments... capable of eliminating steady-state errors and step changes in the reference current. using control approaches that can dampen any overshoot that may occur during this process It is important. 35 During continuous monitoring of a high-current power element, the power element... Safe operation is also important. The power element must be fast at the gate line. 6 Peak gate currents and oscillations can occur during voltage transitions, requiring control. If the output remains in a floating state, the power element will be partially conducting in an undesirable manner. can remain and transient voltage surges or faulty control signals can penetrate the gate oxide layer. It can cause damage. Therefore, in addition to the current regulation function, the gate current... limiting, suppressing oscillations in the door line, driving signal 5 reliable shutdown and gate-source voltage limitation when not present. A protective mechanism is also needed. When known solutions are considered together, embedded and laboratory-type power supplies... In adapting to compact applications, high-power operational amplifier-based drives have a 10% success rate. In current and thermal management requirements, open-loop arrangements for load and supply to compensate for changes and to ensure smooth and low-voltage operation of PWM-based power stages. It appears that there are various shortcomings in providing alternating current. Furthermore... Implementation of current profiles that can be programmed via external or embedded software, 15 Variable resistance loads without the need for any feedforward load model a single system for controlling and protecting the power element under fault conditions It is important that they are accommodated together within a compact structure. In conclusion, all the problems mentioned above necessitate an innovation in the relevant technical field. has made it mandatory. 20 A BRIEF DESCRIPTION OF THE INVENTION The present invention aims to eliminate the aforementioned disadvantages and to contribute to the relevant technical field. To gain new advantages, 25 through a load with variable electrical resistance. the current passing through is in a closed loop relative to a programmable reference current. regulation, feedback based on measured current of changes in load resistance compensation through operating a power MOSFET in the linear region. High-frequency fluctuations and sudden current transitions occur due to switching. ensuring a smooth and continuous load current without interruption and with different current levels 30 a current regulator that enables the implementation of current profiles via software It is related to the circuit. One purpose of this invention is to regulate the current flowing through a load with variable electrical resistance. a 35 that regulates precisely and in a closed loop according to a programmable reference current. The goal is to design a current regulator circuit. 7 Another aim of this invention is to reduce the electrical resistance of the charge depending on temperature, phase transformation, and Joule voltage. due to self-heating, changes in material properties, or aging automatic feedback based on measured current that detects the changes that occur. The goal is to create a current regulator circuit that compensates for this. Another objective of this invention is to enable the operation of the power MOSFET in the linear region. high-frequency fluctuations and inrush currents resulting from switching transitions by preventing variations, it provides a smooth, continuous and low ripple load current. The goal is to design a current regulator circuit. Another objective of this invention is to determine the desired reference current and the current profile to be applied. via embedded or external software without requiring any hardware changes. programming and current regulator circuit by an external master control system a trend that enables its integration into more comprehensive control structures through command The goal is to create the regulator circuit. 15 Another aim of this invention is to enable shape memory alloys to withstand temperature and phase transformation. Despite their varying electrical resistances, the Joule heating current is precise, uniform, and a current regulator circuit that enables its repeatable application to put. 20 Another objective of this invention is to reduce the peak current at the gate line of the power MOSFET. limiting, suppressing oscillations, power when there is no door sliding voltage. Reliable shutdown of the MOSFET and limiting of the gate-source voltage. The goal is to develop a current regulator circuit that provides this. 25 All the purposes mentioned above and those that will emerge from the detailed explanation below. The present invention aims to achieve uniform and variable electrical resistance application to loads with varying electrical resistance. It is a current regulator circuit that provides programmable current. Accordingly, variable The current flowing through a load with electrical resistance is determined by a programmable reference 30. current regulator circuit that enables regulation of the current in a closed loop. Its characteristic feature is the ratio of the reference current that is desired to pass through the load to the measured current passing through the load. to identify a current fault between currents and a gate connected to that current fault A PID control unit configured to generate a driving voltage is connected to the gate terminal. Adjusting the drain current passing through the load depending on the applied gate sliding voltage. 35 a power MOSFET arranged in series with the load and the current passing through the load to measure the current and send a feedback signal representing the measured current to the PID control unit. 8 A current sensor arranged in series with load and power MOSFETs to transmit current. It includes a power MOSFET that ensures the measured current converges to the desired reference current. to ensure continuous channel conductivity depending on the gate opening voltage The invention is designed to operate in a linear region where the current is modified. In the regulator circuit, the current flowing through the load is measured and sent back to the PID control unit. feeding, changes in the electrical resistance of the load in a closed loop It ensures continuous compensation within the power MOSFET's cutoff and conduction phases. instead of switching between states, it is operated in a linear region, channel its conductivity and the associated drain current are continuous with respect to the gate operating voltage. It allows for adjustment. Thus, the measured current can be adjusted to the desired reference current. converging and switching-induced high-frequency fluctuations and inrush currents A smooth and continuous load current is provided without the need for transitions. A feature of a possible configuration of the invention is that the PID control unit combines the current error with each other. It contains a proportional arm, an integral arm, and a derivative arm that operate in parallel, and the proportional 15 The outputs of the main arm, the integral arm, and the derivative arm form the gate driving voltage. It is the collection of current errors. In this structure, the current error is calculated using parallel proportional, integral, and derivative equations. Processing in the arms allows for the individual adjustment of different dynamic characteristics of the control loop. This provides rapid responses to reference changes by bringing the exits of the arms together. A gate that responds, corrects persistent deviation, and reduces overshoot during transient conditions. 20 Driving stress is created. A feature of a possible design of the invention is that the proportional arm has a proportional current error. to apply gain, determine the time integral of the current error of the integral arm, and Applying an integral gain to the determined integral value and the current of the derivative branch 25 to determine the derivative of the error with respect to time and to assign a derivative gain to the determined derivative value. It is structured to implement the system. In this structure, the proportional gain is the ratio of the measured current to the actual gain. It provides a direct response to and control of the instantaneous difference between the desired reference current. It enables the determination of the dominant bandwidth of the loop. Integral gain, load The steady-state error that may occur due to resistance can be corrected cumulatively by 30. This allows for the elimination of current error. Derivative gain, on the other hand, is the change in current error. by enabling the assessment of the speed during step-by-step reference changes It creates predictive damping and reduces current overshoot. A feature of a possible configuration of the invention is that the PID control unit is located in a microcontroller with 35 This is the configuration to execute a programmed PID control algorithm. In this configuration, the PID control algorithm is implemented on a microcontroller. 9 the desired reference current and control parameters without requiring hardware changes It enables programming. Thus, the same circuit can adapt to different load conditions and operating conditions. It can be adapted to specific points and current profiles via software. A feature of a possible configuration of the invention is that the PID control algorithm is implemented in 5 microcontrollers. Execution within a fixed-period interrupt, current in each control period the sensor's output is passed through an analog-to-digital converter of the microcontroller sampling and updating of the gate sliding voltage, PID calculation performed. Within the interrupt service routine, the microcontroller's digital-to-analog converter output is connected to a digital-to-analog converter. It is written in this structure that the control algorithm is written within a fixed-period interrupt for 10 execution of current sampling, PID calculation and gate sliding update processes It ensures that it is carried out with deterministic timing. Data obtained from the current sensor. Sampling of analog voltage with analog-to-digital converter and updated gate slide. the voltage to the digital-to-analog converter output within the same interrupt service routine The writing of the timing variability between measurement and adjustment of the power MOSFET is 15 It reduces. A key feature of a possible implementation of the invention is that the desired reference current is embedded in software. programmed via and generated by an external master control system It is updated according to the commands. In this configuration, the desired reference current is embedded software 20 programming via the system and commanding it by an external main control system, physical circuit elements of the operating point or the current profile to be applied It allows the current to be determined without modification. Programmable reference current, current as part of more comprehensive and dynamic control algorithms of the regulator circuit operation and high-level control of shape memory alloy actuators 25 This facilitates their integration into their systems. A feature of a possible configuration of the invention is that the PID control unit measures the current over time. gate sliding mechanism to enable it to follow the desired reference current, which varies depending on the current. It is the continuous updating of the voltage. In this configuration, the door sliding voltage is updated over time by 30 Continuous updating based on a reference current that varies depending on the current, not just constant current. not only current levels but also variable current profiles are applied to the load. This provides feedback based on the measured current, causing a change in the load resistance. Even if it does not, it contributes to tracking the trend profile in question. 35 A feature of a possible configuration of the invention is that the power MOSFET is N-channel and incremental. It is implemented as a multi-mode power MOSFET. In this configuration, it is an N-channel and incremental mode device. The use of a multi-mode power MOSFET means that the element operates when no gate driving voltage is applied. It is in the closed position and the channel conductivity is checked as the gate sliding voltage is increased. This enables a high load current to be used as a low-power gate driving signal. It can be continuously regulated through this method. A feature of a possible configuration of the invention is that the current sensor is positioned over the drain of the power MOSFET. placed in series with the line, galvanically isolated from the load circuit, and measuring the current as a Hall effect current sensor that produces a linear analog voltage output representing This is the implementation. In this configuration, the use of a Hall effect current sensor, load It enables the measurement of the current in a galvanically isolated manner from the load circuit. 10 The series arrangement in the drain line allows the current regulated through the power MOSFET to flow directly. It allows for the measurement of negligible series resistance and linear analog voltage. The output reduces the additional voltage drop in the load line and the measurement signal. the microcontroller can read the signal without requiring additional signal conditioning. It provides. 15 A feature of a possible configuration of the invention is that the load of the current regulator circuit is the current. The sensor and power MOSFET are connected to the load to be regulated and powered via the MOSFET. a direct current 20 realized in the form of a direct current source or a battery It includes a power supply. In this configuration, the direct current power supply, load, and current The sensor and the power MOSFET supply the current path, measuring the current and power. The load current regulated through the MOSFET must correspond to the same current. It provides a regulated direct current source or battery option, for fixed installations and It enables compatibility with portable applications. 25 A feature of a possible configuration of the invention is the high-speed voltage of the current regulator circuit. to limit the peak gate current of the power MOSFET during transitions and the power MOSFET to create a low-pass filter that suppresses oscillations along with gate capacitance 30 arranged in series between the driving voltage source and the gate terminal of the power MOSFET. It includes a series resistor. In this configuration, the series resistor placed in the door sliding line is fast. peak current passing through the power MOSFET gate during voltage transitions It is limiting. The series resistance, together with the gate capacitance of the power MOSFET, creates... The low-pass design suppresses oscillations at the door line, resulting in a more stable door opening voltage. It ensures that it is implemented in this way. 35 11 A feature of a possible configuration of the invention is the gate bolt mechanism of the current regulator circuit. if the voltage is interrupted or the output of the PID controller remains in a floating state To enable the power MOSFET to turn off, connect the power MOSFET's gate terminal to the source. It includes a pull-down resistor arranged between the terminals. In this configuration, power The pull-down resistor connected between the gate terminal and the source terminal of the MOSFET is 5 Discharging the electrical charge on the door when there is no voltage present on the door. This ensures that the door sliding voltage is interrupted or the control output floats. If this situation remains undesirable, the power MOSFET may partially conduct. is prevented A feature of a possible configuration of the invention is the power MOSFET of the current regulator circuit. To limit the gate-source voltage, the power MOSFET's gate terminal is connected to the source. It contains a Zener diode connected in the clamping direction between the terminals. This clamping the power MOSFET between the gate terminal and the source terminal in the configuration. A Zener diode connected in this direction prevents the gate-source voltage from exceeding the specified maximum value. This prevents transient voltage surges or excessive gate speeds caused by embedded software. Risk of damage to the door oxide layer due to sliding values. is being reduced. A feature of a possible configuration of the invention is that the door sliding voltage source and power 20 A series resistor arranged in series between the gate and terminal of the MOSFET provides power. A pull-down resistor is connected between the gate terminal and the source terminal of the MOSFET. and clamping between the gate terminal and the source terminal of the power MOSFET. It includes a connected Zener diode and a series resistor, a pull-down resistor, and a Zener diode. The diode's function is to limit the peak gate current and suppress oscillations in the gate line, respectively. 25 When there is no gate voltage, the power MOSFET switches off and the power MOSFET switches off the gate. It involves creating a gate sliding protection network to limit the source voltage. This The design utilizes a series resistor, pull-down resistor, and Zener diode together; peak Gate current limitation, suppression of oscillations in the gate line, gate sliding signal. When not present, reliable shutdown and gate-source voltage limiting functions are not available. 30 It combines the power MOSFETs into a single gate sliding protection network. Thus, both the normal and power MOSFETs are integrated. Both its stability under operating conditions and its protection against fault conditions are being improved. A feature of a possible configuration of the invention is that the charge is subject to temperature and phase. a shape memory alloy spring with electrical resistance that varies depending on the configuration or shape 35 It is realized as shape memory alloy wire. In this structure, shape memory alloy the electrical resistance of the spring or wire depends on temperature and phase transformation 12 Compensation for the changes that occur within the feedback loop, Joule heating. This ensures that the current is less affected by the instantaneous electrical state of the alloy. Thus, the shape memory effect is created more precisely and smoothly. A repeatable current application is being performed. BRIEF DESCRIPTION OF THE FIGURES Figure 1 shows the electrical connections of the current regulator circuit, which is the subject of the invention. The circuit diagram is provided. Figure 2 shows the closed-loop control structure of the current regulator circuit, which is the subject of this invention. A block diagram illustrating this is provided. DETAILED DESCRIPTION OF THE INVENTION In this detailed description, the invention concerns a 15-bit reduction of electrical resistance through a load with variable electrical resistance. the current passing through is in a closed loop relative to a programmable reference current. the regulation, feedback based on measured current of changes occurring in load resistance compensation via power supply, operation of the power MOSFET in the linear region. thanks to switching-induced high-frequency fluctuations and sudden current transients ensuring a smooth and continuous load current without creating a differential current 20 a current that enables the application of current profiles with levels via software The regulator circuit is purely for better understanding of the subject and has no limiting effects. This is explained with examples that will not create a problem. The present invention specifically reduces electrical resistance to temperature, phase change, current level or 25 the current flowing through loads that change over time is converted to a programmable reference current. a current regulator circuit that enables precise and closed-loop regulation according to (100) is related to. Thanks to the invention, the load resistance or supply voltage changes The effect of changes on the load current is reduced; this is due to pulse width modulation. Discrete switching transitions, high-frequency current surges, and sudden current changes 30 A smooth, continuous, and programmable current is provided without the need for any alterations. Thus, phase-dependent changes occur, particularly in shape memory alloys operated via Joule heating. Precise current control despite nonlinear electrical resistance variations. is being carried out. 35 The current passing through a load with variable electrical resistance (500) can be programmed. The invention describes a current that can be regulated in a closed loop according to a reference current. 13 regulator circuit (100); the reference current (Id) that is desired to pass through the load (500) and the load To determine the current error (e) between the measured current (I) passing through (500) and the word to generate a gate driving voltage (Vgate) depending on the current fault (e) A configured PID control unit (200) applies gate driving to a gate terminal (G). Depending on the voltage (Vgate), the drain current (Idrain) passing through the load (500) is continuously 5 a power connected in series with the load (500) for adjustment and operated in a linear region To measure the current flowing through the MOSFET (300) and the load (500) and represent the measured current (I). load (500) and power to transmit a feedback signal to the PID controller unit (200) It includes a current sensor (400) arranged in series with the MOSFET (300). The PID control unit (200) controls gate 10 according to the feedback signal received from the current sensor (400). The drive voltage (Vgate) is adjusted; the power MOSFET (300) is linear without switching. By working in the area, the channel conductivity and the associated drain current (Idrain) are continuously monitored. It changes the current (I) so that the measured current (I) converges to the desired reference current (Id). changes in the electrical resistance of the load (500) are provided by any feedforward This is compensated without the need for a load model, and the high 15 caused by switching is compensated. obtaining a smooth and continuous load current without sudden current transitions caused by frequency fluctuations. is being done. The invention's current regulator circuit (100) also includes the load (500), current sensor (400) and power A 20 arranged in connection with the load (500) to feed the MOSFET (300) through it. It includes a direct current supply source (600). The current regulator circuit (100) of the invention also has the power of the gate driving voltage (Vgate). To enable the application of the MOSFET (300) to the gate terminal (G), the gate slider 25 in series between the voltage source and the gate terminal (G) of the power MOSFET (300). It contains a series resistor (700). The current regulator circuit (100) of the invention also includes the cutting of the gate driving voltage (Vgate). or if the output of the PID control unit (200) remains in a floating state, the power MOSFET (300) to ensure the power MOSFET (300) is switched off by connecting the gate terminal (G) to the source 30 It includes a pull-down resistor (800) arranged between terminal (S). The subject of the invention is the current regulator circuit (100) and also the gate-source of the power MOSFET (300). To limit the voltage (VGS), the power MOSFET (300) is connected to the gate terminal (G) of the source. It contains a Zener diode (900) connected in the clamping direction between the terminal (S). 35 14 Figure 1 shows the power MOSFET (300), load (500), DC supply (600), and series resistor. between (700), pull-down resistor (800), Zener diode (900) and current sensor (400) Electrical connections are shown. Figure 2 shows the closed-loop control structure of the current regulator circuit (100) of the invention. It is shown. The invention's current regulator circuit (100) is a digital circuit implemented in embedded software. an analog power stage formed around a power MOSFET (300) with a control loop It includes. The digital control loop shown in Figure 2, passing through the load (500) 10 It determines the gate driving voltage (Vgate) by processing the current feedback signal. The analog power stage shown in Figure 1 operates depending on the specified gate driving voltage (Vgate). It continuously adjusts the drain flow (Idrain) passing through the load (500). In one application, the load (500) contains a shape memory alloy. The shape memory alloy has 15 The electrical resistance is linear depending on the temperature of the alloy and the phase it is in. It changes in an unusual way. The shape memory alloy is operated via Joule heating. In order to control the characteristic shape memory effect during the load (500) the current passing through is precise, independently of the resistance changes in question. It needs to be regulated. The current regulator circuit (100) is closed based on the measured current. By applying cyclic control, the effects of these resistance changes on the load current can be determined. It compensates for its effect. In one application, the load (500) is a shape memory alloy spring or a shape memory alloy wire. It is in the form of. However, the load (500) is not limited to the shape memory alloy, 25 an electrical resistance that can change during operation, and which has a resistive or predominantly resistive character. It can be in the form of a load. The subject of the invention is the current regulator circuit (100); for the operation of shape memory alloys. In Joule heating applications, electrochemical processes, plasma welding, 30 in high-power LED drivers, battery charging or discharging test devices, and thermal or It can be used in electromagnetically operated devices. Current regulator circuit. (100), smooth, precise and programmable high current especially under variable load conditions It is used in applications where it is required. 35 As shown in Figure 2, the PID control unit (200) controls the desired reference current (Id) with the current The current error (e) is the difference between the current (I) measured by the sensor (400) and the current (I). It operates accordingly. The current error (e) in question is expressed by the following equation: e = Id - I Here, Id is the programmable reference current that is desired to pass through the load (500); I, 5 It represents the actual load current measured by the current sensor (400). As shown in Figure 2, the PID control unit (200) parallels the current error (e). a proportional arm (210), an integral arm (220) and a derivative arm (230) It includes the outputs of the proportional arm (210), the integral arm (220) and the derivative arm (230), 10 the gate driving voltage (Vgate) to be applied to the gate terminal (G) of the power MOSFET (300) They are gathering to form. The proportional arm (210) applies a proportional gain (Kp) to the current error (e). Proportional arm (210) determines the dominant bandwidth of the control loop and the desired 15 of the measured current (I). This enables it to respond to changes in the reference current (Id). The integral arm (220) determines the integral of the current fault (e) with respect to time, and the determined It applies an integral gain (Ki) to the integral value. The integral arm (220) is non-zero. If a load resistance is present, proportional control will only result in 20. This eliminates the steady-state error that may occur. Thus, the measured current (I), the desired reference current (Id) independent of the electrical resistance of the load (500) Convergence is achieved. The electrical resistance of the load (500) depends on temperature, Joule self-heating, phase transformation, material 25 If the integral arm (220) changes due to changes in its properties or aging, The measured current (I) can be increased or decreased until it matches the desired reference current (Id). It applies cumulative correction. Thus, the decrease in load resistance that occurs over time... Changes are automatically compensated for within the closed loop. The derivative arm (230) determines the derivative of the current fault (e) with respect to time and the determined It applies a derivative gain (Kd) to the derivative value. The derivative arm (230) is the desired Predictive damping during step changes in the reference current (Id) It provides protection and reduces current overload. 35 The proportional arm (210), the integral arm (220) and the derivative arm (230) together determine the proportional gain (Kp), integral gain (Ki) and derivative gain (Kd); response speed, steady-state accuracy and 16 It allows for independent adjustment of transient damping. It provides. In one application, the PID control unit (200) is a PID control programmed in a microcontroller. The algorithm is implemented in such a way as to execute it. The microcontroller receives 5 current signals from the current sensor. (400) Measured current (I) and desired reference current (Id) according to the received feedback signal calculating the current error (e) between them, executing the PID control algorithm and each It updates the gate actuation voltage (Vgate) in the control loop. In one application, the PID control algorithm uses a deterministic 10-bit timing for the control loop. to ensure this, a fixed-period interrupt is used within the microcontroller. is being carried out. At the beginning of each control period, the output of the current sensor (400) is being sampled, PID calculations are being performed, and the gate driving voltage is being updated. (Vgate) is created within the same interrupt service routine. In one application, the analog voltage taken from the current sensor (400) is converted to a microcontroller. It is sampled via an analog-to-digital converter. PID control unit (200) The gate driving voltage (Vgate), determined by the microcontroller, is a digital-to-analog voltage. It is generated via a converter. The updated gate voltage (Vgate) is PID. The calculation is performed within the interrupt service routine using digital-analog 20. The text is written to the converter output. The operating speed of the control loop has sufficient bandwidth to track the desired current profile. The load (500) significantly exceeds the dominant time constant in such a way as to provide its width. It is determined in such a way as to be fast. Thus, the current passing through the load (500) is the desired 25 Rapid and precise detection of time-dependent changes in the reference current (Id) is following. The desired reference current (Id) in an application is obtained via embedded software. It is programmed. In an application, the desired reference current (Id) is fed into the current regulator circuit. (100) according to the commands generated by an external main control system connected to it. It is being updated. Thus, the operating point of the circuit or the load (500) No hardware modifications are required to change the current profile to be applied. No requirement exists. Programmable reference current (Id) external main control The current regulator circuit (100) is more comprehensive and 35 can be commanded by the system. its use in conjunction with dynamic control algorithms and consisting of shape memory alloy It enables the integration of actuators into high-level control systems. 17 In one application, the current regulator circuit (100) has a reference that changes as a function of time. It enables the current to be applied to the load (500). In this application, the PID control unit (200), the measured current (I) should follow the desired reference current (Id) which changes over time. It continuously updates the gate voltage (Vgate) to provide the following: 5 In an application, a single microcontroller can manage multiple independent current channels. It can be configured to control the load current for each channel in this application. measured separately, the corresponding gate voltage (Vgate) is the reference voltage for that channel. It is determined independently according to the current (Id). 10 The power MOSFET (300) shown in Figure 1 and Figure 2 is part of the current regulator circuit (100) It forms the main control element in the analog power stage. Power MOSFET (300), Channel conductivity depending on the gate driving voltage (Vgate) applied to the gate terminal (G). and therefore regulates the drain flow (Idrain) passing through a drain terminal (D). 15 The power MOSFET (300) has cutoff and as in a pulse width modulation driver. Instead of switching between transmission states, it operates in a linear region. Within the scope of the present invention, the linear region is the drain-source resistance of the power MOSFET (300). 20 refers to the operating region where the gate-source voltage (VGS) changes continuously. The PID control unit (200) controls the channel conductivity and drain of the power MOSFET (300). The gate-source voltage (VGS) is adjusted in real-time to set the drain current (Idrain) to the desired value. It is changing it as follows. The drain current (Idrain) of the power MOSFET (300) is the gate-source 25 for a given drain-source voltage. It changes continuously and monotonically depending on the voltage (VGS). Thus, the load (500) The current passing through it is changed continuously via the gate instead of discrete switching transitions. It is regulated via the driving voltage (Vgate). In one application, the power MOSFET (300) is a 30 N-channel and enhancement-mode It is implemented in the form of a power MOSFET. In one application, the power MOSFET (300), Figure As shown in Figure 1, in the form of an IXTH110N10L2 model power MOSFET. is realized. The low conduction state resistance of the power MOSFET (300) and High continuous drain current capacity, power MOSFET (300) at 24 V supply voltage This makes it suitable for high-current operation. 35 18 The power MOSFET (300) operates in the linear region throughout the predicted current range. It is being operated and does not enter the cutoff or saturation zone during normal operation. Thus, switching transitions cause high-frequency fluctuations in the load current. It is not happening. Thanks to keeping the power MOSFET (300) outside of the switching transitions, the load (500) the switching frequency in the current passing through and that frequency No fluctuations occur due to harmonics. Thus, a smooth, continuous process is achieved. A modulated and ripple-free load current is provided. Switching Since no voltage or current surges occurred, the surges in question were 10 An output filter is not needed to eliminate this problem. Operating the power MOSFET (300) in the linear region, compared to a switched driver This can lead to higher power loss on the power MOSFET (300). In practice, the thermal load resulting from this power loss is at an acceptable level of 15. In order to keep it in place, the power MOSFET (300) is used together with a suitable heatsink. In applications where energy efficiency is a priority, coarse current adjustment is provided. Pulse width modulation control combined with linear precision current adjustment. It can be used. In this hybrid application, 20 through pulse width modulation. Coarse tuning is performed and linear control of the power MOSFET (300) is carried out. Precise adjustment is provided. This ensures that the ability to provide a smooth output current is maintained while maintaining power. The loss can be reduced. The current sensor (400) shown in Figure 2 measures the current passing through the load (500) and 25 a feedback signal representing the measured current (I) is sent to the PID control unit (200) It transmits the feedback signal. The feedback signal in question is transmitted by the PID control unit (200), power MOSFET. (300), control loop created via load (500) and current sensor (400) It is closing. As shown in Figure 1, the current sensor (400) is connected in series to the drain line of the power MOSFET (300). It is connected as follows. In one application, the current sensor (400) is a Hall effect current sensor. This is implemented in the following way. The Hall effect current sensor detects current galvanically from the load circuit. It is isolated, creates a negligible level of series resistance in the load line, and is measured. It produces a linear analog voltage output representing the current. Hall effect current sensor 35 The analog voltage output generated by (400) requires an additional signal conditioning process. without requiring, directly by the microcontroller's analog-to-digital converter 19 It is readable. Due to these features, the Hall effect current sensor (400) is preferably used for current preferred compared to current measurement performed using a measuring resistor (shunt resistor). is being done. In one application, the current sensor (400) reduces the measurement errors caused by parasitic effects by 5. application for the purpose of reducing and measuring current (I) to reflect the actual load current. It is positioned as close to the load (500) as conditions permit. As shown in Figure 1, the DC supply source (600) connects the load (500) to the current sensor. (400) and the power MOSFET (300) are fed through the drain terminal (D). A 10 In practice, the DC supply source (600) is a regulated DC supply. or is implemented in the form of a battery. In one application, a direct current supply source (600) provides a supply voltage of 24 V. It provides. The supply voltage in question is 15 even if the electrical resistance of the load (500) changes. sufficient voltage allowance across the drain-source junction of the power MOSFET (300) protection and linearity of the power MOSFET (300) within the predicted operating current range. This ensures that it remains in the region. In one application, the current regulator circuit (100) supplies a direct current of 24 V. to provide a programmable load current of up to 10 amps with the source (600). It is structured. In one application, the current regulator circuit (100) has a value of 24 V. a load current of up to 4 amperes with a direct current supply (600) It is organizing. The series resistor (70Ω) shown in Figure 1 is powered by the gate driving voltage (Vgate) source. The MOSFET (300) is arranged in series between the gate terminal (G). (700) peak gate current of power MOSFET (300) during fast voltage transitions limiting and suppressing oscillations together with the gate capacitance of the power MOSFET (300). It forms a low-pass filter. In one application, the series resistor (700), 100 Ω resistor 30 It has a resistance value of [value]. This resistance value represents the peak current in the door sliding line. It ensures the limitation and suppression of oscillations. The pull-down resistor (800) shown in Figure 1 is the gate terminal (G) of the power MOSFET (300). It is arranged between the source terminal (S). The pull-down resistance (800), door sliding If the voltage (Vgate) is interrupted or the microcontroller output remains in a floating state, 35 This ensures that the power MOSFET (300) is completely switched off. Thus, the power MOSFET (300) It is prevented from remaining in a partial transmission state in case of a fault. In an application The pull-down resistor (800) has a resistance value of 10 kΩ. This resistance value is the gate resistor. When there is no driving signal, the power MOSFET (300) is reliably in the off state. It ensures that it is held. The Zener diode (900) shown in Figure 1 is connected to the gate terminal (G) of the power MOSFET (300) by 5 The source terminal (S) is connected in the clamping direction. Zener diode (900), gate gate-source of power MOSFET (300) regardless of the level of the driving signal It limits the voltage (VGS) to a specified maximum value. In one application, a Zener diode (900) limits the gate-source voltage (VGS) to 15 V. Thus, the typical absolute maximum The gate oxide layer of the power MOSFET (300) with a gate-source voltage of 20 V has a transient voltage of 10 embedded software that can lead to surges or the application of excessive gate voltage It is protected against overvoltage damage caused by faults. Series resistor (700), pull-down resistor (800) and Zener diode (900), together form the power MOSFET. (300) forms the door sliding protection network. The door sliding protection network in question; peak 15 limiting the gate current, suppressing oscillations in the gate line, gate sliding signal. When not present, the power MOSFET (300) should reliably shut down and the gate oxide should be removed. It provides protection of the layer against overvoltage. The desired reference current (Id) during the operation of the current regulator circuit (100) is measured in step 20. If increased in this way, the PID control unit (200), the power MOSFET (300) gate It increases the gate actuation voltage (Vgate) applied to the terminal (G). An increase in voltage (Vgate) increases the gate-source voltage (VGS) of the power MOSFET (300). and reduces channel resistance. As a result of the reduction in channel resistance, the load (500) is reduced. A higher drain flow can pass through. 25 The current sensor (400) detects the increase in load current and measures the current (I). It feeds the measured current (I) to the PID controller (200). The PID controller (200) Continue adjusting the gate driving voltage (Vgate) until it equals the desired reference current (Id). It is. 30 If the desired reference current (Id) is reduced in step form, the PID control unit (200), This reduces the gate voltage (Vgate). The reduction in gate voltage (Vgate) increases power. It reduces the gate-source voltage (VGS) and channel resistance of the MOSFET (300). It increases the channel resistance. As a result of the increase, the current passing through the load (500) is 35 is decreasing. Measured depending on the feedback provided by the current sensor (400). The current (I) converges to the reduced desired reference current (Id). 21 Since the power MOSFET (300) does not perform any switching operation, the desired Load current, PID gains and control during step change in reference current (Id) a smooth transition towards the new set value shaped by the bandwidth of the cycle It exhibits a transition. Thus, the voltage resulting from sudden switching transitions or 5 No current pulses are occurring. Changes in the impedance of the load (500) due to closed-loop operation, without the need for any feed-forward model regarding the load It is constantly compensated. The electrical resistance of the load (500) Joule self-heating, temperature, 10 Phase transformation, changes in material properties, or aging are significant factors. Even if the measured current (I) changes to the desired reference current (Id), the PID control unit (200) changes the measured current (I) to the desired reference current (Id). It enables tracking. The current regulator circuit (100) of the invention can handle loads with variable electrical resistance. the current passing through is fast and precise relative to a programmable reference current (Id). its regulation; thanks to the operation of the power MOSFET (300) in the linear region. to generate a smooth, continuous and low ripple load current; in the load resistance automatic compensation of changes via integral feedback and door sliding 20 Reliable operation of the power MOSFET (300) through the protection network It provides. The scope of protection of the invention is specified in the claims attached hereto, and these details are strictly adhered to. The explanation cannot be limited to those given for illustrative purposes. Because a technically skilled person... 25 similar ideas in light of what has been described above, without deviating from the main theme of the invention. It is clear that these structures can emerge. 22 REFERENCE NUMBERS GIVEN IN THE FIGURE 100. Current regulator circuit 200. PID controller unit 210. Proportional arm 220. Integral arm 5 230. Derivative branch 300. Power MOSFET 400. Current sensor 500. Load 600. DC power supply 10 700. Series resistor 800. Pull-down resistance. 900. Zener diode I. Measured current Id. Reference current 15 e. Current fault Vgate. Gate sliding voltage. G. Gate terminal Idrain. Drainage flow. S. Source terminal 20 VGS. Gate-source voltage. Kp. Proportional gain Ki. Integral gain Kd. Derivative gain D. Drain terminal 25
Claims
23 REQUESTS 1. Current passing through a load (500) with variable electrical resistance closed-loop regulation based on a programmable reference current (Id) It is a current regulator circuit (100) which provides 5 through the load (500). the reference current (Id) that is desired to pass through the load (500) and the measured current (I) passing through the load (Id) to determine the current fault (e) between them and the current fault (e) A PID controller configured to generate gate driving voltage (Vgate). (200), load depending on the gate drive voltage (Vgate) applied to the gate terminal (G). To adjust the drain flow (Idrain) passing through (500), load (500) is in series with 10 a power MOSFET (300) and load (500) arranged in conjunction with each other. to measure the current and send a feedback signal representing the measured current (I) to the PID controller The load (500) and power MOSFET (300) are connected in series to transmit to the unit (200). It includes a current sensor (400) and a power MOSFET (300), Gate 15 ensures that the measured current (I) converges to the desired reference current (Id). channel conductivity is continuously changed depending on the driving voltage (Vgate) It is designed to be operated in a linear region.
2. A current regulator circuit (100) according to claim 1, and its characteristic is; PID control unit (200), current fault (e) a proportional branch (210) operating in parallel, a 20 It includes an integral arm (220) and a derivative arm (230) and a proportional arm (210), integral The gate driving voltage (Vgate) of the outputs of the lever (220) and the derivative lever (230) It is the gathering to form.
3. According to claim 2, a current regulator circuit (100) has the characteristic of; the proportional arm (210) 25 Applying a proportional gain (Kp) to the current error (e), the current of the integral arm (220) to determine the integral of the error (e) with respect to time and to assign a value to the determined integral value Applying integral gain (Ki) and current error (e) of the derivative arm (230) to time to determine the derivative and a derivative gain (Kd) based on the determined derivative value It is structured for implementation. 30 4. A current regulator circuit (100) according to any of the above requirements, Its feature is that the PID control unit (200) is a PID programmed in a microcontroller. It is the configuration to execute the control algorithm. 35 5. A current regulator circuit (100) according to claim 4, and its feature is; PID control The algorithm is executed within a fixed-period interrupt on the microcontroller. 24 In each control period, the output of the current sensor (400) is sent to the microcontroller. Sampling and updating of the gate slide via an analog-to-digital converter. The interrupt service routine where the voltage (Vgate) PID calculation is performed. It involves writing to the output of a digital-to-analog converter from the microcontroller.
6. A current regulator circuit (100) according to claim 4 or 5, whose characteristic is; required The reference current (Id) is programmed via embedded software and an external master. It is updated according to the commands generated by the control system.
7. According to any of the above requirements, a current regulator circuit (100) is, 10 Its feature is that the PID control unit (200) measures the current (I) as a function of time. the gate driving voltage to ensure that it follows the desired reference current (Id) (Vgate) is constantly updating.
8. A current regulator circuit (100) according to any of the above requirements, 15 Its feature is that the power MOSFET (300) is an N-channel and incremental mode power MOSFET. This is how it is carried out.
9. A current regulator circuit (100) according to any of the above requirements, Its feature is that the current sensor (400) is connected in series with the drain line of the power MOSFET (300) 20 placed, galvanically isolated from the load circuit and representing the measured current (I) as a Hall effect current sensor that produces a linear analog voltage output It is the realization of.
10. According to any of the above requirements, a current regulator circuit (100) is 25 Its feature is; load (500) through current sensor (400) and power MOSFET (300). connected to the load (500) to supply a regulated direct current a direct current supply source implemented in the form of a power source or a battery (600) is included.
11. A current regulator circuit (100) according to any of the above requirements, Its feature is the peak gate current of the power MOSFET (300) during fast voltage transitions. limiting and oscillating together with the gate capacitance of the power MOSFET (300). To create a suppressive low-pass filter, power is supplied via a gate-driven voltage source. A series 35 MOSFET (300) is arranged in series between the gate terminal (G). It contains resistance (700).
12. A current regulator circuit (100) according to any of the above requirements, Its feature is the interruption of the gate driving voltage (Vgate) or the PID control unit (200) If the output remains in a floating state, the power MOSFET (300) will turn off. to provide power MOSFET (300) gate terminal (G) and source terminal (S) It includes a pull-down resistance (800) arranged between them. 5 13. A current regulator circuit (100) according to any of the above requirements, Its feature is to limit the gate-source voltage (VGS) of the power MOSFET (300). Clamping of the MOSFET (300) between the gate terminal (G) and the source terminal (S). It contains a Zener diode (900) connected in the direction of 10.
14. A current regulator circuit (100) according to any of claims 1 to 10, Feature; gate terminal (G) of power MOSFET (300) with gate driving voltage source a series resistor (700) arranged in series between the gates of the power MOSFET (300) A pull-down resistor 15 is connected between terminal (G) and source terminal (S). (800) and between the gate terminal (G) and source terminal (S) of the power MOSFET (300). It includes a Zener diode (900) connected in the clamping direction and a series resistor (700), pull-down resistor (800) and Zener diode (900) peak gate current, respectively To limit and suppress oscillations in the gate line, gate sliding voltage (Vgate) If not present, turn off the power MOSFET (300) and the power MOSFET (300) gate-20 It involves creating a gate actuation protection network to limit the source voltage (VGS).
15. A current regulator circuit (100) according to any of the above requirements, its characteristic; the load (500) varies depending on the temperature and the phase it is in. a shape memory alloy spring or shape memory alloy wire with electrical resistance 25 This is how it is carried out.