Position sensor-less vector control with sinusoidal current waveforms is applied to the compressor drive system using an IPMSM for higher efficiency and lower acoustic noise. This paper proposes control methods suitable for compressor drives. For the position estimator, an armature flux based full-order adaptive observer is used. Pole of the observer is selected at a constant real value to simplify the system design. Novel compensation methods using BPF are applied to reduce the cyclic speed change and the current waveform distortion. The inductance measuring method and the starting method are also applied. Principles of the methods are presented as well as experimental results.
Japan set up the long-term R & D roadmap titled “PV2030” in 2004. This roadmap assumes the mass deployment of 100GW PV aggregation will supply 10% of national electricity up to year 2030. Under this condition, PV penetration will reach almost 100% in the majority of urban areas, which may allow less harmonization with the conventional power grid due to the frequent and huge reversal power flow from PVs. The authors have developed new concepts called “autonomy-enhanced PV cluster (AE-PVC)” to realize a less dependent PV aggregation on the existing power grids. This paper describes a configuration and functions of a battery storage station, which performs energy control in AE-PVC.
In this paper, we propose a discontinuous conduction current mode (DCM) control method for three-phase four-line buck-boost power factor corrected (PFC) converter and its soft-switching circuit configuration. The PFC converter generates three phase sinusoidal input currents by switching operation of constant frequency, constant duty factor and open loop control. To improvement of input current waveform, a new control method for soft-switching converter is described.
The Bridge type converter magnetize transformer on positive and negative directions, while forward type converter magnetize transformer on one direction. For that reason, forward type converter is considered that it operate only in the first quadrant of BH curve. But the careful observation of the transformer voltages and currents brings us to the new understanding that the magnetizing current of the transformer flows not only to positive direction but also to negative direction, which derives the new theory that the transformer operate not only at the first quadrant of BH curve but also at the third quadrant. In this paper we probe the new theory by the analysis of magnetizing current and propose a new design method of transformer.
This paper is mainly concerned with an advanced soft-switching PWM power supply incorporating boost- half-bridge inverter topology suitable for consumer induction heating. The operating performances of this inverter are illustrated and evaluated on the experimental results, including the power regulation vs. duty cycle characteristics and efficiency characteristics based on the power dissipation as compared with those of previously developed inverter. Its effectiveness is substantially proved on the basis of the experimental results from a practical point of view.
This paper describes a hollow cathode keeper power supply and an anode power supply for a hall thruster on artificial satellites. In the keeper power supply, it is required that the electric discharge characteristic is excellent and the current control characteristic is stable. In the anode power supply, it is required that the electric discharge characteristic is excellent, the voltage control characteristic is stable and the efficiency is high. We confirm that these electric discharge characteristics are excellent with the experimental models. Furthermore, we confirm these control characteristics are stable for the hollow cathode and the hall thruster made as experimental models. Lastly, it is reported on the condition to suppress the electrical discharge oscillation phenomenon of a hall thruster.
This paper presents the results of an investigation into the end-effect in Interior Permanent Magnet Synchronous Motors (IPMSM) with rare-earth magnets. The 6-slot/4-pole concentrated winding machine with different stack length and permanent magnet arrangement is used in this study. The analysis shows that the end-effect decreases the normalized magnet torque productivity and increases the resistance to demagnetization as the stack length decreases. The latter indicates that thinner stack length provides higher electric loading for the given demagnetizing factor and, therefore, higher torque density can be expected. Another important point is that an increase in embedded depth of permanent magnet raises the end-effect impact. From these results, to have a higher torque density, the ultra-thin IPMSM with deeply embedded PM type rotor is preferred.
A new type of soft switched bidirectional DC-DC converter for advanced automotive electric power systems is presented in this paper. This converter consists of dual half-bridge circuits linked with a high frequency transformer, which is applicable as an interface between a high-voltage DC bus line and a low-voltage power source such as Supercapacitor. In order to reduce the switching losses and expand the soft switching range, a newly developed two-lossless switched capacitor snubber-assisted Zero Current Switching (ZCS) are applied to the primary side circuit. By using this ZCS scheme, the soft switching operation can be achieved for the wide range of output power. The converter operation is demonstrated with simulation results, and its feasibility is verified with experimental results using its 1.0kW 25kHz prototype system.
This paper discusses the constant DC capacitor voltage control method of the non-active current compensator using the correlation function. The linearized model of the constant do capacitor voltage control block is derived, and then the relationship between the capacitance of the do capacitor and power flows into the non-active current compensator. It is shown that the capacitance can be decided considering only the power flow caused by the unbalanced situation. Digital computer simulation is implemented to verify the validity of the linearized model. The prototype experimental model is constructed and tested. Experimental results demonstrate that the linearized model is useful to design the do capacitor and PI controller.
Generally, conventional type active filter utilizes voltage source inverter, which requires high frequency switching devices in order to compensate high order harmonics. But due to the switching frequency characteristics of the devices, it is difficult to reduce the electro-magnetic noise. So we proposed a combined-type active filter using linear power amplifier and low-switching frequency converter. Presently, there is a problem which spike-like current occur power supply current at the time of load changes. In this paper, we propose compensation method of current at the time of load changes.
As one of the effective dismantlable adhesion method, “the allover method” for interior construction using induction heating and thermoplastic adhesive has been proposed. Also, the induction heating for long structure metals with a traveling magnetic field using linear induction coils was proposed as uniform heating method. This paper describes a uniform heating method on flat metals of wide area using an improved linear induction coils and its thermal and power analysis. The proposed method for flat metal heating would be usefulness not only interior adhesion construction of floor panel or tiles but other industrial applications.
In this paper, we presented the simulation coupling magnetic field analysis and circuit analysis for power module. Parasitic impedance and MOSFET device were modeled for SPICE simulation. We applied the simulation for System in Package (SiP) power module and showed that efficiency and voltage waveform could be calculated with high accuracy.
This paper describes about developments of motor control technology for home appliances with simulation tools based on MATLAB/Simulink. A real-time simulation system and a circuit simulator “SimPowerSystems” were used for a development of a vibration control in Drum-type Washer/Dryer. And we used a behavior model by which magnetic saturation was able to be considered to develop a novel sensor-less control method for IPMSM.
“DC Micro-grid” is a novel power system using dc distribution in order to provide a super high quality electric power. The dc distribution system is suitable for dc output type distributed generations such as photovoltaic and fuel cells, and energy storages such as batteries and electric double layer capacitors. Power is distributed through dc distribution line and converted to required ac or dc voltage by converters placed near loads. Load-side single inverters are connected with transformer in order to share active and reactive power. In this paper, we proposed active and reactive power control methods for load-side inverter. Simulation results demonstrate controlled characteristics of the proposed method.
This paper presents a complex type common-source active clamp converter. By adding a second winding to the transformer, and using two active-clamp switches connected in common-source type, the switching loss and switching noise can be reduced by means of the soft switching techniques. Furthermore, the complex type common source active clamp converter is constructed with the connection of a main switch to the boost inductor, can achieve corresponding to wide input range. The operation and characteristic of complex type common-source active converter is introduced.
Linear synchronous reluctance motors (LSynRM) need to many sensors along track, but the price of the sensor is very high. Therefore we need to know mover position with sensorless. In this paper, the sensorless mover position detection for the LSynRM with magnetic suspension is proposed. The characteristics of the LSynRM with double side stator are analyzed by finite element method (FEM). The control characteristic of sensorless position control is simulated by MATLAB, and compared with position control with sensor. We show that it can be controlled mover position by using the sensorless estimation position.