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In industrial application on machine manufacturer multinational company, especially on the conveyor manufacturing company, before delivering the conveyor to overseas customer, there are some regulations need to be complied to ensure the product quality is always good. The system to ensure the product quality before delivery is named by Factory Acceptance Test (FAT). The purpose of doing this is to gain the trust and satisfaction of the buyer company by ensuring the quality before delivery. To ensure the product quality, this device was designed following the customer check sheet and requirement by giving them reliable data of the load current on each line of the motor and the motor temperature. This device is consisting of WEMOS D1 mini as the main controller and an IoT device, thermocouple type K as a temperature sensor, MAX6675 as the driver of the thermocouple, SCT-013-005 as a split-core current sensor, Arduino Nano as the second controller, and LCD 2004 as a real-time display. The IoT Application for Conveyor Motor Load Current and Temperature Monitoring Device is successfully created with the output is a table of data and the line chart which consists of Load current on each phase (U1, V1, W1), the motor temperature, and the limitation of each data so the user is easier to determine the commissioning result of the Factory Acceptance Test.

This paper presents the development of a hot air dryer conveyor for the automotive industry in the tampo printing part process. The research started by designing and creating the actual device that is ready to use and be implemented in the industry. The method provides the detail of the drying chamber, hot air dryer, and its mathematical model. The chosen hot air dryer is Suiden SHD-9F II and is operated on the factory default setting of auto-tuning mode. The performance evaluation studies the indicator performance of hot air dryer for the chosen size of drying chamber, the robustness of the system against fluctuating environmental air change rate, the ducting capacity, and the damper opening value estimation performance. The result of this system is working well at specification requirement of air change rate from 15 to 21 at 80% of its maximum capacity for error compensation and its already being successfully implemented.

In electronics design and troubleshooting, the function generator is an important and versatile electronic test equipment. But the prices of finished function generator sold on market is expensive and not everyone can afford it. In order to create an economic and reliable function generator, microcontroller-based DDS function generator designed. AD9833 is DDS based programmable function generator from Analog Devices, which capable to producing sine, triangular and square wave output. To make an easy to use and flexible function generator, AD9833 connected with 4x4 matrix membrane keypad and LCD 1602. The microcontroller-based DDS function generator successfully created. The waveform generated by AD9833 offers not only exceptional accuracy and stability, but also low phase noise, an excellent frequency change and sudden waveform change ability, its useful in a wide variety of testing applications.

Setiap beberapa waktu perawat melakukan pemantauan tetes cairan infus dengan manual secara langsung. Bahkan, saat cairan infus akan habis, keluarga pasien harus memanggil perawat untuk melakukan penggantian cairan infus. Hal ini bisa menyebabkan terlambatnya penanganan terhadap pasien karena keterbatasan waktu. Oleh sebab itu, dibutuhkan sebuah alat pemantauan tetes cairan infus yang dapat memberikan notifikasi otomatis bahwa cairan infus akan habis. Artikel ini menjelaskan tentang implementasi alat pemantauan tetes cairan infus berbasis IoT yang terhubung dengan perangkat android. Prototipe ini menggunakan sensor Optocoupler sebagai pendeteksi adanya tetes cairan infus, Motor Servo SG90 untuk menekuk selang infus, Mikrokontroler ESP32 sebagai pengendali. Komunikasi perangkat keras dengan perangkat android menggunakan server lokal sehingga harus menggunakan Hotspot WiFi yang sama. Data yang dikirimkan dari perangkat android akan tersimpan ke database kemudian diakses oleh ESP32 sehingga menjalankan sensor dan motor servo. Pada android application terdapat informasi kondisi tetes cairan infus yang sudah dikonversi menjadi persentase sisa cairan infus. Hasil eksperimen menunjukkan bahwa prototipe dapat melakukan pengaturan tetes cairan infus per menit sesuai dengan yang diinginkan dan android application dapat menampilkan status dan mengirimkan notifikasi secara akurat. Sebagai kesimpulan dari hasil pengukuran, rata – rata rasio persentase yang dicapai dalam pengujian mencapai 70 % dengan rata – rata error sebesar 1,46 %.

This study proposes a voltage-oriented control scheme for four-quadrant grid-tie of a single-phase bidirectional direct current/alternating current (AC) voltage-sourced converter (VSC) to operate smartly at modes of unity power factor (PF) rectifier (UPFR), inverter or static var compensator. Given the possible harmonic-distorted AC grid voltage, the proposed scheme follows or filters the grid voltage to generate the appropriate current command template for minimising the harmonic current while synchronising with the grid. The following template is for the UPFR mode, whereas the filtered template is for the other modes. The scheme proposes a unique band-pass filter (BPF) to proceed with direct component generation for the filtered template. The proposed scheme further unifies the grid-tie inductor current-to-voltage conversion for the following emplate and the quadrature component generation for the filtered template into a differentiator. The control laws under the filtered and following templates are derived. The BPF and differentiator designs are introduced. Simulations and experiments are conducted with a one-cycle control full-bridge VSC to verify the proposed grid-tie control scheme and evaluate its performance.

Metal-oxide-semiconductor field-effect transistor (MOSFET) can be utilized to raise switching frequency (SF) while zero voltage switching-clamped voltage (ZVS-CV) is a simple technique to eliminate switching loss without extra resonant circuit. Then, heat sink and filter can both be so shrunk that compact inverter can fit the single-phase system in residential site while high efficiency fulfills regulation(s). In order to ensure the ZVS-CV operation, the inverter’s filter inductor must flow such high ripple current that can charge or discharge parasitic capacitances of a MOSFET totem pole, however trades off conduction loss of MOSFET. This study proposes a simple scheme for adapting the SF ripple current to the profile of line frequency (LF) sinusoid meanwhile ZVS-CV operation is maintained, thus efficiency is optimized. Simulations are conducted with 220 V 60 Hz LF single phase full-bridge buck inverter to verify the efficiency enhancement on a load about 1 kW.

For wireless sensor networks (WSN) applications, harvesting energy source is important since the sensor does not utilize power from the main power line. Among all harvesting energy sources, thermoelectric generator (TEG) becomes interesting because of its unlimited self-life (self-sufficient in energy). However, to maximize the TEG output power, then ratio between input resistance and load resistance should be maintained to be unity. For that purpose, this paper presents study on various simple power tracking such as perturbed and observe (P&O), Incremental Conductance (INC) and Three-Point Weight Comparison (TPWC). Simulation results show that all methods can keep the TEG maximum power, but with different level of power oscillation at the maximum power point (MPP)

This paper presents rehabilitation robot with torque control with impedance scheme for post-stroke patients in the upper limb of the shoulder. This impedance scheme consists of external force input and impedance value. The external force input comes from the load cell at the end of the robot (the end effector), which is generated by the patient's force. The input force consists of two Cartesian directions, which will affect the robot dynamic torque for the X-axis and Y-axis. Meanwhile, the value of the impedance in the robotic system is provided by the therapist who handles the stroke patients. The amount of impedance in the robotic system can be adjusted according to the patient's condition. In this paper, we used 3 DOF (Degree of Freedom) self-produced robots. The rehabilitation trajectory consists of two parameters, the position parameter, and the torque control parameter in the impedance system. The impedance scheme in the robotic system use impedance characteristics and Proportional Integral (PI) controller. Proportional Integral (PI) controller is used as a simulation control in tracking errors of position and the torque impedance of the robot. With a simple controller, the characteristics relationship between the changes in the magnitude of the external force produced by the patient and the change in impedance values given to the robot system are obtained. By knowing these characteristics, robots can interact with various types of stroke patients.

A differential boost inverter (DBI) consists of two bidirectional boost converters and has a differential sinusoidal output voltage. This output voltage is obtained because each bidirectional boost converters generates a dc-biased sinusoidal voltage. Owing to this characteristic, this inverter topology requires a controller that can track a dc-biased sinusoidal voltage as the control reference. One cycle control (OCC) is a non-linear control approach that can meet the requirements and be easily implemented in a simple circuit with constant switching frequency. The controller must be capable of achieving a unity power factor (PF) because the inverter is designed to deliver maximum active power to the grid. Therefore, the sinusoidal reference signal of the OCC is formed by the scaled grid voltage and its derivation. Given this reference signal, the inverter output voltage represents the grid voltage with a small variation phase and amplitude. Furthermore, this strategy will guarantee that the output current and the grid voltage are in phase. An experimental prototype of DBI is implemented to verify that the control approach can achieve PF close to unity such that the maximum active power can be delivered to the grid with minimum current total harmonic distortion.

A thermoelectric generator (TEG) converts thermal energy directly into electrical energy. The principle work of this device is known as a Seebeck Effect. The TEG can be used effectively to harvest low thermal energy to power a low power Wireless Sensor Node (WSN). As the same as solar cells, the TEG connection can be a distributed string either in parallel or in series. However, the performance of the TEG string due to the inhomogeneity temperature gradient in each TEG is still not well investigated. This paper presents the effect of the inhomogeneity temperature gradient on the performance characteristics of the TEG string. The test is carried out using a Thermoelectric Cooler (TEC) as a thermal source on the TEG string. The experimental result is provided to verify the performance of the TEG in various cases of this inhomogeneity temperature gradient.

Series-connected lead-acid battery is commonly used in a photovoltaic system. During charge-discharge cycle, each battery in the string would experience a voltage imbalance which leads to performance decay. Single switched capacitor battery balancer resolves this issue by transferring excessive charge from one battery to another. Therefore, the voltage imbalance will be at the acceptable limit. A transfer element is employed in this charge transfer process between batteries. In this paper, a battery balancer has been carried out by adopting balancing algorithm used in an LTC3305 chip. Simulation result shows that the use of the lead-acid battery as a transfer element is considerably more effective than the super-capacitor while speeding-up the balancing process.

In a grid-connected photovoltaic (PV) system, an inverter should have a capability not only to track the maximum power of PV module but also to synchronize the output current to the grid. In the previous work, a grid-connected single-stage inverter based on differential topology with an analog one-cycle controller (OCC) has been proposed. However, the inverter lacks PV power tracking capability. In this paper, a simple maximum power point tracking (MPPT) technique is studied to be integrated to the proposed inverter. The MPPT technique is based on the inverter output current adjusting. The simulation results verify that the designed MPPT can extract the power maximum of PV module and the inverter can maximally deliver the photovoltaic power to the grid.

This paper presents an implementation of a DSP- based shunt active power factor corrector (PFC). The working principle of four-switch series-connected PFC is introduced. To examine the actual circuit characteristics, MATLAB/Simulink is used to implement circuit of shunt active PFC and analyze the relations between the load, VE DC voltage, source voltage and current. Analysis of circuit of the digital shunt-connected active PFC includes main circuit diagram and control circuits, such as adders, voltage converters, electric current sensors, feedback circuits and hardware circuit structure, calculation of main circuit inductance and design of capacitance value. Based on the control rule of source current slope, the relation between output capacitance voltage of the single-phase shunt PFC and source current waveform distortion is discussed. Finally, the influence of the efficiency with fixed capacitor voltage is shown in the experiment result.

In the application of lead-acid series batteries, the voltage imbalance of each battery should be considered. Therefore, additional balancer circuits must be integrated into the battery. An active battery balancing circuit with an auxiliary storage can employ a sequential battery imbalance detection algorithm by comparing the voltage of a battery and auxiliary storage. The system is being in balance if the battery voltage imbalance is less than 10mV/cell. In this paper, a new algorithm is proposed so that the battery voltage balancing time can be improved. The battery balancing system is based on the LTC3305 working principle. The simulation verifies that the proposed algorithm can achieve permitted battery voltage imbalance faster than that of the previous algorithm.

This paper presents a one-cycle controller of buck inverter with a current limiter. In some applications, a buck inverter is widely used to convert a higher input DC voltage to a lower output AC voltage. There are some types of buck inverter such as full-bridge, half-bridge, differential, and so on. For a buck inverter with differential type, one-cycle control (OCC) can be easily implemented because it has a simple design. It has also another advantage including an ability of disturbance rejection. Since OCC is designed to work in voltage mode, it has no capability to control the output current. Therefore, a current limiter is important to be integrated to the controller. The simulation verification shows that by integrating the current limiter to the controller, overshoot of output current can be limited to the certain value without decreasing the controller performance.

Sensor flex sering digunakan sebagai sensor untuk mendeteksi perubahan pergerakan jari, namun nilai perubahan sensor tersebut belum tentu berbanding lurus dengan perubahan pergerakan jari. Dalam artikel ini akan membahas penggunaan dua sensor untuk mengetahui respon pergerakan jari, yaitu dengan sensor flex dan sensor IMU. Sensor flex diletakkan pada area metacarpal hingga distal phalange. Pada area proximal phalange dan distal phalange diletakkan sensor IMU untuk mendeteksi sudut yang dibentuk pada gerakan jari. Informasi tersebut digunakan sebagai acuan untuk melihat respon resistansi sensor flex pada titik sudut yang sama saat jari melakukan pergerakan menekuk. Hasil percobaan pada pengujian sensor flex didapatkan bahwa gerakan untuk membuka dan menggenggam pada semua jari memberikan respon pola yang sama namun terdapat perbedaan resistansi diperulangan dan didapatkan ∆R rata-rata sebesar 0.12%. Dengan melakukan pengamatan pada θ_DIP dan θ_PIP, dapat diketahui respon resistansi sensor flex pada masing-masing sudut tekuk tiap jari. Dengan pengamatan pada θ_DIP, θ_PIP dan sensor flex, maka pendeteksian pergerakan jari akan menjadi lebih presisi.

One-cycle control (OCC) is widely used in many power converter topologies because of its advantages. However, in the control process, OCC uses integration of chopped diode voltage to control the output voltage of the converter where, in the case of the dc-dc buck converter, the chopped diode voltage represents only the input voltage. Thus, it will lead to the nonzero steady state error of the output voltage. Moreover, the output disturbance will have more effect to the converter performance. In this paper, a type-III compensator is designed for improving the performance of one-cycle controlled buck converter. Furthermore, the controller can eliminate both input and output disturbance with zero steady-state error. The simulation results verify the performance of the designed controller.

This paper presents a DSP-based differential boost inverter (DBI) with maximum power point tracking (MPPT) for photovoltaic (PV) applications. In a conventional DC/AC MPPT system, power of photovoltaic is delivered into two stages, they are DC/DC boost converter and buck type DC/AC inverter. A DC link capacitor appears between these two stages. Furthermore the system has higher complexity and costly than that of DC/AC MPPT system with a single stage boost inverter. Here, a single stage differential boost inverter is implemented. Since it can produce a sinusoidal output voltage higher than its DC voltage input, it is not only able to reduce the stage number of DC/AC MPPT system but also able to eliminate the DC link capacitor. The MPPT method employed in this study is P&O method. This technique is widely used due to its easy implementation, and unimportant extreme weather change consideration. To implement this technique, a digital signal processor (DSP) was used. In this paper, a review of DBI and MPPT implementation are presented. Finally a 400 W laboratory prototype has been built. The result shows that the P&O MPPT method has been successfully implemented for various PV power and it can reach 95% maximum MPPT accuracy. In addition, the DBI is able to produce a sinusoidal output voltage at the various PV power conditions.

Isolated power factor correction converters expose several shortcomings such as: the presence of slow-recovery diodes on conduction path leading to conduction losses and complexity in sensing circuit. This paper presents a new topology named isolated dual boost bridgeless PFC converter not only to improve efficiency by discarding of the low-recovery diodes but also to simplify the sensing circuit methodology. Additionally, a laboratory prototype with 100-140 V input, 400 V/750 W output was built and verified to demonstrate the circuit feasibility in this study. The experimental results shown that the efficiency improved by using bridgeless converter concept.