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To increase output torque in the constant power region of interior permanent magnet synchronous motor (IPMSM) for electric vehicle/hybrid electric vehicle applications, a novel torque control based on voltage phase angle control is proposed to provide more accurate torque for the IPMSM. First, the mathematic model of the IPMSM under six-step voltage operation is derived. Then, the phasor diagram based on the fundamental frequency and ideal condition is used to explain the relation between the torque, power, and voltage phase angle. Moreover, Maxwell 2D simulation for the IPMSM shows the detailed phenomena including generated torque, phase current, and magnetic flux distribution for developing controllers. Hence, the proposed method uses phase voltage advancing angle to yield torque, which consists of a command feed-forward controller to give a fast dynamic response, a proportional-integral regulator, a high-resolution voltage angle injection to reduce torque ripple and an efficiency-based torque estimator to enhance torque accuracy under six-step voltage operation. Finally, a digital signal processor(DSP)-based motor drive is built to verify the proposed method using a 6 kW/47 Nm/1200 rpm IPMSM. The experimental results measured by a torque transducer are derived to show that the torque ripple is significantly reduced, torque accuracy is improved, and constant power control achieved is from 1800 to 3600 rpm. These results, therefore, confirm the superior performance of the proposed control method.

Objective: The objective of this study is to explore the treatment and compatibility principles of Traditional Chinese Medicine. Materials and Methods: Syndrome differentiation is used to identify the etiology, nature, and location of a disease and the relationship between the healthy Qi and pathogenic factors by analyzing and synthesizing the four diagnostics data. The theory of treatment is to determine the principle and methods of treatment according to the results of syndrome differentiation and implement them as a specific prescription. This paper bears witness to the principle universality by analysis of the articles of the Banxia Xiexin Decoction, and it equally has analogical prescriptions in Treatise on Febrile Diseases. Results: The treatment and compatibility principles of Traditional Chinese Medicine are the same, that is, rectifying the deviation on three dimensions, strengthening the healthy Qi, and eliminating pathogenic factors in the light of its general trend. Conclusion: The treatment and compatibility principles of Traditional Chinese Medicine are the same, The treatment and compatibility principles provide a new thinking for clinical treatment.

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In domestic induction heating applications, cookware can be considered an equivalent load in a series resistor–inductor–capacitor resonant converter. Therefore, the electrical parameters of an equivalent circuit change according to the cookware material, size and the cookware position on the heating coil. This study proposes an online estimation method for detecting the cookware status, determining the material and estimating the equivalent heating resistance of cookware on an induction heating cooker (IHC) for power control. The proposed method could turn off the circuit in abnormal situations such as low equivalent heating coverage rate or non-ferromagnetic cookware and adjust the power in normal situations. In the method, a half-bridge series resonant converter (HBSRC) generates two test patterns with three resonant voltage pulses to detect cookware every 10 ms, only the current feedback information is needed to avoid the calculation loads and times necessary for complex signal operations in software. To verify the proposed method, a digital signal processor based HBSRC with 1000 W was constructed. The maximum errors between the estimated and measured resistance and inductance were 7.14% and 2.91%, respectively. Moreover, power control in emulated user operation reveal that the proposed method and control system can effectively estimate load online to detect cookware status and determine whether to turn off or vary the heating power for an IHC.