Automatic Power Control Research Articles

A Temperature Based Automatic Power Controller for Electrical Devices

In this paper, a controller is proposed to design in such a way that it can be able to control the input voltage as well as power to any load or electrical device not only manually i.e. through the computer but also automatically i.e. based on temperature. We propose this design for the reason that a part of the electrical appliances are needed to control the input power for getting the desired output from those which depend on the variation of temperature. Sometimes equipments can be needed manual control. For this purpose, computer controlling is also inserted here rather than supplying manpower. In this design, the voltage control technique is used to control the power to the load. Here, the output of the controller will vary on the sense that the variation of the surrounding temperature selects the relay which is connected to regulating coil to control the output voltage as well as power. The main specialty of this research is to maintain enhanced precision and hysteresis without harmonics in output variation.

Automatic power controlled, load compensated magnetic resonant wireless power transmitter

As compared to other wireless transfer mechanism, like the inductive coupling method, magnetic resonance-based wireless power transfer can achieve power transfer over a larger distance. However, as the transmission range increases, the change in the load impedance lowers the transmission efficiency in the currently available magnetic resonance-based wireless power transmitters. This article presents a CMOS transmitter for magnetic resonant wireless battery charging system. A class-E power amplifier (PA) with an automatic power control loop and load compensation circuit is proposed to improve the power efficiency. The transmitted power is controlled by adjusting the signal applied to the gate of the power control transistor. In addition, a parallel capacitor is also controlled to enhance the efficiency and compensate for the load variation. The proposed design is implemented using 0.35 μm BCD technology with an active area of around 5 mm × 2.5 mm. The transmitter provides an output power control range of 9–30.2 dBm. The measured maximum power efficiency of the PA is 70.2%.

A high efficiency transmitter and receiver for magnetic resonant wireless battery charging system in 0.35 μm BCD

This paper presents a transmitter and receiver for magnetic resonant wireless battery charging system. In the receiver, a wide-input range CMOS multi-mode active rectifier is proposed for a magnetic resonant wireless battery charging system. The configuration is automatically changed with respect to the magnitude of the input AC voltage. The output voltage of the multi-mode rectifier is sensed by a comparator. Furthermore, the configuration of the multi-mode rectifier is automatically selected by switches as original rectifier mode, 1-stage voltage multiplier or 2-stage voltage multiplier mode. As a result, a rectified DC voltage is output from 7.5 to 19 V for an input AC voltage of 5---20 V. In the transmitter, a class-E power amplifier (PA) with an automatic power control loop and load compensation circuit is proposed to improve the power efficiency. The transmitted power is controlled by adjusting the signal applied to the gate of the power control transistor. In addition, a parallel capacitor is also controlled to enhance the efficiency and compensate for the load variation. This chip is implemented using 0.35 μm BCD technology with an active area of around 5,000 × 2,500 μm. When the magnitude of the input AC voltage is 10 V, the power conversion efficiency of the multi-mode active rectifier is about 94 %.The maximum power efficiency of the receiver is about 70 %. The transmitter provides an output power control range of 10---30.2 dBm. The maximum power efficiency of the PA is 71.5 %.

Ball Mill Automatic Control System Design Based on Fuzzy PID Control

For ball mill grinding process random interference by many factors, processes complex mechanism, there is a big inertia and the lag, the fuzzy control theory is introduced into the mill control system, has strong robustness, can effectively overcome the mill main motor power nonlinear, time-varying factors such as interference. System is reliable, adjust speed, anti-interference ability, can better achieve constant power automatic control of the ball mill, with good application value.

WPON 응용을 위한 고속 CMOS어레이 광트랜스미터

본 논문은 멀티 채널의 어레이 집적 모듈을 갖는 광트랜시버를 위한 2.5 Gbps 어레이 VCSEL driver의 설계 및 구현에 관한 것이다. 본 논문에서는 광트랜시버에 적용된 1550 nm high speed VCSEL을 드라이브하기 위하여 <TEX>$0.18{\mu}m$</TEX> CMOS 공정 기술을 이용하여 자동 광전력제어 기능을 갖는 2.5 Gbps VCSEL (수직 공진기 표면 방출 레이저) 드라이버 어레이를 구현하였다. 광트랜스미터의 폭넓은 대역폭 향상을 위해 2.5 Gbps VCSEL Driver에 네가티브 용량성 보상을 갖는 능동 궤환 증폭기 회로를 채용한 결과 기존 토폴로지에 비해 대역폭, 전압 이득 및 동작 안정성의 뚜렷한 향상을 보였다. 4채널 칩은 최대 변조 및 바이어스 전류하에서 1.8V/3.3V 공급에서 140 mW의 DC 전력만 소모하고, 다이 면적은 기존 본딩 패드를 포함하여 <TEX>$850{\mu}m{\times}1,690{\mu}m$</TEX>를 갖는다. In this paper, the design and layout of a 2.5 Gbps arrayed VCSEL driver for optical transceiver having arrayed multi-channel of integrating module is confirmed. In this paper, a 4 channel 2.5 Gbps VCSEL (vertical cavity surface emitting laser) driver array with automatic optical power control is implemented using <TEX>$0.18{\mu}m$</TEX> CMOS process technology that drives a <TEX>$1550{\mu}m$</TEX> high speed VCSEL used in optical transceiver. To enhance the bandwidth of the optical transmitter, active feedback amplifier with negative capacitance compensation is exploited. We report a distinct improvement in bandwidth, voltage gain and operation stability at 2.5Gbps data rate in comparison with existing topology. The 4-CH chip consumes only 140 mW of DC power at a single 1.8V supply under the maximum modulation and bias currents, and occupies the die area of <TEX>$850{\mu}m{\times}1,690{\mu}m$</TEX> excluding bonding pads.

Performance Investigation of Isolated Wind–Diesel Hybrid Power Systems With WECS Having PMIG

This paper presents the automatic reactive power control of isolated wind-diesel hybrid power systems having a permanent-magnet induction generator for a wind energy conversion system and a synchronous generator for a diesel generator set. To minimize the gap between reactive power generation and demand, a variable source of reactive power is used such as a static synchronous compensator. The mathematical model of the system used for simulation is based on small-signal analysis. Three examples of the wind-diesel hybrid power system are considered with different wind power generation capacities to study the effect of the wind power generation on the system performance. This paper also shows the dynamic performance of the hybrid system with and without change in input wind power plus 1% step increase in reactive power load.

High stable single-polarization tunable fiber laser based on Opto-DMD processor and polarization-maintaining fiber devices

A high stable wavelength-tunable fiber laser is experimentally demonstrated by using a digital-micromirror-device (DMD) processor and a polarization-maintaining erbium-doped fiber amplifier (EDFA).The electronic-addressed DMD processor is able to select and couple a waveband from of the polarization-maintaining EDFA back into the fiber ring to generate a narrow line-width laser output. The tunable fiber laser shows a line-width of 0.02 nm, a tuning step of 0.08 nm over the c-band and a side mode suppression ratio (SMSR) greater than 50 dB. The output power uniformity of 0.01 mW is achieved by using the automatic power control (APC) system under room temperature. The center wavelength fluctuation during 1 h is below 0.01 nm.

Compensation of Reactive Power of Isolated Wind-Diesel Hybrid Power Systems

This paper presents the automatic reactive power control of an isolated wind-diesel hybrid power system with a synchronous generator (SG) for a diesel genset and an induction generator (IG) with wind energy conversion systems (WECS) to generate electricity. To reduce the gap between reactive power generation and demand, a variable source of reactive power is used such as static synchronous compensator (STATCOM). The mathematical model of the system based on reactive power flow equations is developed. Three examples of the wind-diesel hybrid power systems are considered with different wind power generation capacities to study the effect of the wind power generation on the system performance. The study is based on small signal analysis by considering IEEE type-1 excitation system for the SG. The paper also shows the transient performance of the hybrid systems for 1 % step increase in reactive power load and 1 % step increase in reactive power load plus 1 % step increase in input wind power.

Transistor Laser Power Stabilization Using Direct Collector Current Feedback Control

An automatic laser power control scheme for the transistor laser has been developed and demonstrated using the transistor laser collector current output. The collector current enables an all-electrical feedback solution for laser power control, obviating the need for a hybrid integrated monitor photodiode. This control scheme enables the simple monolithic integration of the transistor laser and its power control circuits on a single die.

Achieving more efficient control of the power output of power units through the use of differentiation in the boiler controller regulating steam pressure upstream of the turbine

Different versions of systems for automatic closed-loop control of the power output of power units are analyzed. A new version of the automatic power control system is proposed together with a method for tuning it. Results from model studies and tests of the proposed automatic power control system structure at a real plant are presented.

Studying and improvement of Laser Diode Driver performance at 1Gb/s in optical communication system

The Laser Diode Driver (LDD) is an important part in optical communication system; it acts as an interface between the data source and the optical source (Laser). The design of this circuit using CMOS technology which has low conductivity (gm), (less than from bipolar technology), is a challenge for designers especially at high data rate (>1 GB/s) because LDD must provide high current swing to obtain large optical output power. In this research a simulation software using Personal Simulation Program with IC Emphasis PSPICE (2006) is used to study the performance of the LDD circuit using (0.18µmCMOS technology) at (1 GB/s), the peak to peak jitter is (110ps). In addition analyzing an automatic power control circuit, so that when changing the temperature from (0 – 80˚C) the Laser current changing is (5mA), and an improvement of reference voltage circuit has been added, since a constant voltage (319mV) achieved when the power supply voltage changes from (2.15-6V). Keywords: Laser Diode Driver , pre-driver , Extinction Ratio.

Study of an isolated wind–diesel hybrid power system with STATCOM by incorporating a new mathematical model of PMIG

SUMMARYThis paper presents automatic reactive power control of an isolated wind–diesel hybrid power system. A synchronous generator is used for power generation from diesel and a permanent‐magnet induction generator (PMIG) is used for electric power generation from wind turbine. A new mathematical model is developed to incorporate the effect of permanent‐magnet of the PMIG in the generation of reactive power. To eliminate the gap between reactive power generation and demand, a variable source of reactive power is used such as static synchronous compensator (STATCOM). A study on the wind–diesel system is conducted based on small signal analysis by considering IEEE type‐1 excitation system for the synchronous generator. The paper also shows the dynamic performance of the hybrid system both for constant and variable slip conditions and 1% step change in reactive power load. Copyright © 2011 John Wiley &amp; Sons, Ltd.

Safe external reactivity perturbation limits in IBR-2

For the IBR-2 pulsed reactor safe reactivity perturbation limits have been determined by mathematical simulation of reactor dynamics in the plane “input reactivity level–input speed”. From power transients calculated using a reactor model with experimental power feedback parameters safe reactivity perturbation limits corresponding to different years of reactor operation have been obtained.It has been shown that in the course of reactor operation continuous narrowing of the region of permissible reactivity perturbations accompanied by significant fluctuations of the boundaries of the region takes place. The safety limit for some reactivity perturbations has decreased over 3 times in 20years of reactor operation.Such reduction of the region of permissible reactivity fluctuations is connected with gradual degradation of the fast power feedback. It has been demonstrated that the effect is most likely due to increase in the positive feedback component because of changes in thermo-mechanical deformation of fuel elements in the course of power generation.It has been noted that an authorized automated power control system secures safe operation of the reactor even in the case of continuous narrowing of the safety limit.The investigation has been performed at the Frank Laboratory of Neutron Physics, JINR.

A fast automatic power control circuit for a small form-factor pluggable laser diode drive

A fast automatic power control (APC) circuit for a laser diode driver (LDD) has been implemented in a 0.6-μm BiCMOS process. The APC circuit adopts double-loops and variable-bandwidth techniques to achieve a turn-on time of < 400 μs for most kinds of TOSAs. Thus, it meets the small form-factor pluggable (SFP) agreement. Such techniques make a good tradeoff between stability, accuracy, turn-on time, noise and convenience. The measured results indicate that the APC circuit is suitable for SFP LDD.

Differential Monitoring of AWG-Filtered Reflection Signal for Accurate Transmitter Power Control of Injection-Locked WDM PON Systems

We propose a simple and robust, automatic power control architecture for the injection-locked, wavelength-division-multiplexed passive optical network system. Monitoring the differential of reflected signal power from the mid-stage fiber mirror placed after the arrayed waveguide grating in the central office, the problem of transmitted signal power fluctuation experienced in conventional, back-facet photodiode monitoring schemes is eliminated. Results show the excellent control of the transmitted power within a peak-to-peak fluctuation of 0.1 dB over a wide operating range of temperature and injection power level.

High Efficiency Automatic-Power-Controlled and Gain-Clamped EDFA for Broadband Passive Optical Networking Systems

The configuration of a simple improved high efficiency automatic-power-controlled and gain-clamped EDFA (APC-GC-EDFA) for broadband passive optical networking systems (BPON) is presented here. In order to compensate the phase and amplitude variation due to the different distance between the optical line terminal (OLT) and optical network units (ONU), the APC-GC-EDFA need to be employed. A single 980 nm laser module is employed as the primary pump. To extend the bandwidth, all C-band ASE is recycled as the secondary pump to enhance the gain efficiency. An electrical feedback circuit is used as a multi-wavelength channel transmitter monitor for the automatic power control to improve the gain-flattened flatness for stable amplification. The experimental results prove that the EDFA system can provide flatter clamped gain in both C-band and L-band configurations. The gain flatness wavelength ranging from 1530 to 1610 nm is within 32.83 ± 0.64 dB, i.e. below 1.95 %. The gains are clamped at 33.85 ± 0.65 dB for the input signal power of −40 dBm to −10 dBm. The range of noise figure is between 6.37 and 6.56, which is slightly lower compared to that of unclamped amplifiers. This will be very useful for measuring the gain flatness of APC-GC-EDFA. Finally, we have also demonstrated the records of the overall simultaneous dynamics measurements for the new system stabilization. The carrier to noise ratio (CNR) is 49.5 to 50.8 dBc which is above the National Television System Committee (NTSC) standard of 43 dBc, and both composite second order (CSO) 69.2 to 71.5 dBc and composite triple beat (CTB) of 69.8 to 72.2 dBc are above 53 dBc. The recorded corresponding rise-time of 1.087 ms indicates that the system does not exhibit any overshoot of gain or ASE variation due to the signal at the beginning of the pulse.

Performance of a Wind-Diesel Hybrid Power System with STATCOM as a Reactive Power Compensator

The paper deals with automatic reactive power control of an isolated wind-diesel hybrid power system. The power is generated by diesel engine and wind turbine as prime movers with electrical power conversion by permanent-magnet synchronous generator (PMSG) and permanent-magnet induction generator (PMIG) respectively. The mathematical model of the system developed is based on reactive power flow equations. The paper investigates the dynamic performance of the hybrid system for 1% step increase in reactive power load with 1% step increase in input wind power.

Performance of a Wind-Diesel Hybrid Power System with STATCOM as a Reactive Power Compensator

The paper deals with automatic reactive power control of an isolated wind-diesel hybrid power system. The power is generated by diesel engine and wind turbine as prime movers with electrical power conversion by permanent-magnet synchronous generator (PMSG) and permanent-magnet induction generator (PMIG) respectively. The mathematical model of the system developed is based on reactive power flow equations. The paper investigates the dynamic performance of the hybrid system for 1% step increase in reactive power load with 1% step increase in input wind power.

Temperature and power control in microwave drying

A microwave drying system with the ability of automatic temperature and power control was developed for apple drying. The samples’ mass and the moisture content could be obtained online. Four different drying modes were attempted with different combination of temperature and power controls. Feedback temperature control with predefined variable power profiles resulted in the best temperature control and product quality. All other modes proved their own pros and cons. The study also verified that it was difficult to maintain a constant temperature during microwave drying process when a feedback temperature control was not included. The results can be used to determine microwave power levels in microwave drying practices both with and without temperature control.

Power Control Device and Storm Security for Savonius Rotor

The main disadvantage of a Savonius rotor has been its failure to control its power and survive in high winds. A built-in device is developed that provides automatic power control and storm security. This consists of a window on each cup of the Savonius and its spring-loaded shutter that opens centrifugally when a certain rpm is exceeded. A technique for power measurement that employs a wind tunnel balance and the brake-dynamometer principle is developed. A rotor with this device is tested in a wind tunnel under different brake loads, spring tensions and wind speeds. The shutters open reliably to limit rpm and power; the open shutters reduce drag on the rotor and these features should offer protection from centrifugal forces and wind thrust in a storm. Increased shutter spring tension resulted in higher power coefficient. The rotor could not be subjected to extreme winds in the wind tunnel for reasons of safety.