In this paper, a direct torque control (DTC) method of an induction machine is proposed which enables the minimum ripple control, while maintaining constant switching frequency. Some drawbacks conventional DTC are relatively large in low speed range and variation frequency according to amplitude hysteresis bands motor operating speed. strategy, RMS torque-ripple equation derived using instantaneous equations and, at each cycle, optimal instant satisfies condition determined based on...

This paper presents a new sensorless control scheme of surface-mounted permanent-magnet (SMPM) motor using high-frequency voltage signal injection method based on the impedance difference. In SMPM motor, due to flux permanent magnet, stator core around q-axis winding is saturated. makes magnetic saliency in motor. has information about rotor position. The injected into order detect and estimate this paper, relationship between voltages currents developed equations at high frequency,...

A vector control of an induction motor by estimated speed using extended Kalman filter is proposed. With this method, the states are composed stator current and rotor flux. The regarded as a parameter, composite consist original speed. employed to identify flux based on measured quantities such currents DC link voltage. used for overall control. Since performed at synchronous rotating reference frame, information also frame transformation controller. Computer simulations experiments have...

In this paper, a novel dead time compensation method is presented that produces inverter output voltages equal to reference voltages. An experimental result also demonstrate the validity of proposed method. It shows possible up sub-microsecond range. Also, voltage can be used as feedback value, which essential for sensorless vector control and flux estimation. The based on space pulsewidth modulation (PWM) strategy it carried out automatically by an controller initial setup without any extra...

This paper describes a new control algorithm which can enhance the dynamics of sensorless system and gives precise performance. Instead conventional sinusoidal-type voltage injection, square-wave-type injection incorporated with associated signal processing method is proposed in this paper. As result, error be calculated without low-pass filters time delays, position estimation performance enhanced. Using method, enhanced; bandwidth current controller was enhanced up to 250 Hz, that speed 50 Hz.

A novel flux-weakening scheme for the interior permanent magnet synchronous motor (IPMSM) is proposed. This implemented based on output of PI current regulator-reference voltage to PWM inverter. The onset flux weakening and level are adjusted inherently by outer regulation loop prevent saturation regulator. Attractive features this include no dependency machine parameters. guarantee at any operating condition, smooth fast transition into out mode. Experimental results various conditions...

The aim of this study was to develop a new method operate an interior permanent magnet synchronous machine (IPMSM) on the maximum torque per ampere (MTPA) condition. characteristics MTPA condition were analyzed and derived based input electric power. proposed injects small current signal used for tracking operating point along with fundamental generation. This does not require any parameters or premade lookup table. frequency injected is several hundred hertz, performance almost free from...

In conventional motor drive systems using pulsewidth modulation (PWM) inverters, large electrolytic capacitors are used for stabilization of the dc-link voltage. Since bulky and reduce reliability system due to short lifetime, there have been many efforts eliminate or in system. However, PWM inverter with reduced capacitor has a problem that voltage is less stable compared because capability storing energy also reduced. this paper, algorithm an active damping proposed so can be stabilized...

The rotor position of an interior permanent-magnet synchronous machine (IPMSM) can be estimated without a sensor by signal injection sensorless control at standstill and/or in very low speed rotating condition. In the control, however, fundamental performance is limited frequency injected signal, and no negligible acoustic noise generated. If voltage would increase to pulsewidth modulation (PWM) switching if near or above audible range, dynamics improved, remarkably reduced totally...

Six-step operation has many advantages in permanent-magnet synchronous machine (PMSM) drives such as maximum power utilization and widened flux-weakening region. However, due to the of inverter output, saturation current regulator makes it difficult maintain instantaneous control capability. Accordingly, most conventional research studies, six-step been implemented by voltage angle without regulation, whose dynamic performance is quite unsatisfactory. This paper proposes a scheme for PMSM...

The modular multilevel converter (MMC) is a promising candidate for voltage-sourced-converter-based high-voltage direct current (VSC-HVDC) transmission. dc short-circuit fault management crucial issue especially overhead line transmission, where the nonpermanent faults occasionally occur. In this paper, comprehensive ride through (FRT) strategy proposed hybrid MMC which combines half-bridge submodules and full-bridge submodules. By method, MMC-based VSC-HVDC system able to pole-to-pole...

The voltage output is inevitably delayed in a full-digital implementation of current regulator due to an arithmetic calculation and the pulsewidth modulation. In case synchronous frame regulator, time delay accompanied by rotation. some applications where ratio sampling frequency insufficient, such as high-power drive or super-high-speed drive, effect rotation during causes phase magnitude error output. degrades dynamic performance can cause instability at high speed. It also intuitively...

This paper presents the analysis of a surface-mounted permanent-magnet (SMPM) machine for sensorless control scheme based on high-frequency fluctuating voltage signal injection method. A simplified model an SMPM in estimated rotor reference frame is developed and position speed estimation algorithm described. To support this, impedances are analyzed by finite-element (FEA) compared with measurement results using pulsewidth-modulation (PWM) inverter system under various conditions. The FEA...

This paper describes a new scheme to find the rotor flux angle from stator voltages and currents by injecting high-frequency signal. The signal is not rotating one but fluctuating at reference frame synchronously fundamental frequency. When estimated coincides with actual angle, proposed method makes virtually no ripple torque, vibration less audible noise caused injected difference of impedances between axis quadrature injection on explained equivalent circuit equation induction machine....

In this paper, a new voltage modulation technique named "unified pulsewidth (PWM)" is described for high-performance generation in three-phase voltage-fed inverter. By considering the operation of inverter, simple but useful concept "effective time" can be established and, by fully employing concept, presented with detailed explanation and actual test results. The results show that various carrier-based PWM schemes implemented reduced computational burden seamless change from one scheme to...

This paper describes a new scheme to find the rotor flux angle from stator voltages and currents by injecting high-frequency signal. The signal is not rotating one, but fluctuating one at synchronous reference frame with fundamental frequency. When estimated coincides actual angle, proposed method makes virtually no ripple torque, vibration less audible noise caused injected difference of impedances between axis quadrature injection on explained equivalent circuit equation induction machine....

Multiphase motors are usually designed to have the concentrated winding and nonsinusoidal airgap flux density distribution in order maximize torque per ampere. This means that phase voltage of a multiphase motor has waveform. Accordingly, conventional analysis on space vector pulse-width modulation (SVPWM), which is confined sinusoidal voltage, should be extended voltage. In this paper, based multiple d-q spaces concept novel SVPWM synthesize an arbitrary proposed. Throughout five-phase...

In this paper, a novel voltage modulation technique named unified PWM (pulse width modulation) for high performance generation in voltage-fed inverter is described. As increasing the interest quality power conversion is, simple scheme that has wide fitness to general prospect loss minimization and lowest current harmonic with full DC link utilization required. From synthesis of actual action, but useful concept 'effective time' established. And, fully employing concept, new various...

This work presents a method using carrier-frequency injection to estimate the initial rotor position and magnetic polarity for an interior permanent-magnet synchronous machine. A nonsaturating inductance model of machine provides no information about magnet because observer based on this is locally stable at both poles. To distinguish magnet, saturation effect can be used. The Taylor series used describe nonlinear relationship between current flux linkage in d-axis reference frame....

This paper describes the implementation of two vector control schemes for a variable-speed 131-kW permanent-magnet synchronous motor drive in super-high-speed applications. The with reference frame current regulator was implemented challenging requirements such as an extremely low stator inductance (28 /spl mu/H), high DC-link voltage (600 V), and excitation frequency (1.2 kHz). Because conventional position sensor is not reliable at super-high speed, different were proposed to measure...

In this paper a voltage modulation method based on triangular carrier wave for the three-phase four-leg source converter is described. The can produce three output voltages independently with one additional leg. proposed be implemented single by simple but useful "offset voltage" concept. equivalent to so called three-dimensional space vector PWM method, its implementation much easier. maximum magnitude of balanced and zero sequence voltage, which synthesized simultaneously, are derived....

In this paper, system integration and power-flow management algorithms for a four-wheel-driven series hybrid electric vehicle (HEV) having multiple power sources composed of diesel-engine-based generator, lead acid battery bank, supercapacitor bank are presented. The super-capacitor is utilized as short-term energy storage device to meet the dynamic performance vehicle, while mid-term (EV) mode operation due its higher density. generator based on an interior permanent magnet machine (IPMM),...

This work presents a control strategy that provides fault tolerance to the major sensor faults which may occur in an interior-permanent-magnet-motor (IPMM)-based electric vehicle propulsion drive system. Failures of position sensor, dc-link voltage and current sensors are all included study assuming no multiple faults. For each possible fault, corresponding method detection or diagnosis is provided. Additionally, once detected, scheme automatically reconfigured provide post-fault operational...

This paper describes a torque, speed, or position control method at standstill and low speed in the interior permanent-magnet motor (IPMM) drive system without any rotational transducer. While IPMMs have originally magnetic saliency, it varies according to load conditions performance can be easily degraded. In this paper, saliency impedance difference is used as conventional methods and, nevertheless, order amplify containing information of rotor angle maintain reasonable under condition...