EPE Association: NORpie 1998 - Topic 04: ADVANCED CONTROL AND MEASUREMENT

NORpie 1998 - Topic 04: ADVANCED CONTROL AND MEASUREMENT
You are here: EPE Documents > 05 - EPE Supported Conference Proceedings > NORpie - Proceedings > NORpie 1998 > NORpie 1998 - Topic 04: ADVANCED CONTROL AND MEASUREMENT

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   A Method to Compensate for Errors Caused by the Blanking Time in PWM Systems with High Ripple Currents
By Michael Lindgren; Jan Svensson [View]
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Abstract: In PWM converters, the non-linearity caused by the blanking time depends on the direction of the phase current at the commutations. Previous principles for compensating for non-linearities have been based on the sign of the phase current at the sampling instants, and are not able to compensate if the phase current changes sign between the sampling instant and the commutations. At a low power level, such a change of sign occurs for a large part of the line period when PWM converters are connected to the grid. This paper describes a method to solve the problem by predicting the sign of the phase currents at the commutations. Experimental results are presented for a three-phase grid-connected PWM converter controlled by a discrete vector-current controller. The method makes the compensation possible also at low power levels and in systems with small line filters or low sampling frequencies.

   Microwave Telemetry Systems for Measurements of Electric Drives
By Pekka Eskelinen; Olli Pyrhönen [View]
[Download]

Abstract: The combination of a microwave telemetry link and intelligent microelectronic transducers can provide a reliable means for contactless measurement of electric drives also in the presence of high electromagnetic noise levels. Clear advantages include the possibility to install the instrumentation into currently existing motor or generator systems with minor mechanical modifications. Care must be taken to protect the electronics against high g forces. Rotor speed and position are directly measurable from the complex microwave radiation pattern.The proposed technology is extendable to include cg. an adaptive control of dynamic drive performance and can be customized to meet specific speed ranges and parameters. As a test case, torque transient measurements with a 1.1 GHz link are demonstrated.

   PI Control of Web Tension Control System based on Overlapping Decomposition
By T. Sakamoto [View]
[Download]

Abstract: Since a web tension system consists of many subsystems connected with certain dynamics, the interactions make the controller design complex. This situation can become serious when designing the decentralized control system via a disjoint decomposition, where the interactions can be disturbance and a necessaq state variable at the same time. This paper shows a decentralized controller design methodolos based on overlapping decomposition of the controlled object. This methodology can remove the difficulty of consideration to avoiding the mutual interactions between subsystems. Then the controller design becomes easy, and in addition it is shown that we have a good control performance compared with a conventional decentralized controller design based on disjoint decomposition.

   New Methods for Controller Design, Analysis and Validation in the Design of DC / DC Converters
By Idris Gadoura; Kai Heikkinen; Kai Zenger; Petri Vallittu; Teuvo Suntio [View]
[Download]

Abstract: This paper presents a design procedure of a PIDcontroller, which regulates a buck converter operating in continuous-conduction mode with voltage-mode control and current-mode control. Matlab / Simulink and FuzzyTECH are used to design and tune a fuzzy PID controller. All models are validated in saberJ environment.

NORpie 1998 - Topic 04: ADVANCED CONTROL AND MEASUREMENT
You are here: EPE Documents > 05 - EPE Supported Conference Proceedings > NORpie - Proceedings > NORpie 1998 > NORpie 1998 - Topic 04: ADVANCED CONTROL AND MEASUREMENT
	[return to parent folder]

	A Method to Compensate for Errors Caused by the Blanking Time in PWM Systems with High Ripple Currents By Michael Lindgren; Jan Svensson	[View] [Download]
Abstract: In PWM converters, the non-linearity caused by the blanking time depends on the direction of the phase current at the commutations. Previous principles for compensating for non-linearities have been based on the sign of the phase current at the sampling instants, and are not able to compensate if the phase current changes sign between the sampling instant and the commutations. At a low power level, such a change of sign occurs for a large part of the line period when PWM converters are connected to the grid. This paper describes a method to solve the problem by predicting the sign of the phase currents at the commutations. Experimental results are presented for a three-phase grid-connected PWM converter controlled by a discrete vector-current controller. The method makes the compensation possible also at low power levels and in systems with small line filters or low sampling frequencies.

	Microwave Telemetry Systems for Measurements of Electric Drives By Pekka Eskelinen; Olli Pyrhönen	[View] [Download]
Abstract: The combination of a microwave telemetry link and intelligent microelectronic transducers can provide a reliable means for contactless measurement of electric drives also in the presence of high electromagnetic noise levels. Clear advantages include the possibility to install the instrumentation into currently existing motor or generator systems with minor mechanical modifications. Care must be taken to protect the electronics against high g forces. Rotor speed and position are directly measurable from the complex microwave radiation pattern.The proposed technology is extendable to include cg. an adaptive control of dynamic drive performance and can be customized to meet specific speed ranges and parameters. As a test case, torque transient measurements with a 1.1 GHz link are demonstrated.

	PI Control of Web Tension Control System based on Overlapping Decomposition By T. Sakamoto	[View] [Download]
Abstract: Since a web tension system consists of many subsystems connected with certain dynamics, the interactions make the controller design complex. This situation can become serious when designing the decentralized control system via a disjoint decomposition, where the interactions can be disturbance and a necessaq state variable at the same time. This paper shows a decentralized controller design methodolos based on overlapping decomposition of the controlled object. This methodology can remove the difficulty of consideration to avoiding the mutual interactions between subsystems. Then the controller design becomes easy, and in addition it is shown that we have a good control performance compared with a conventional decentralized controller design based on disjoint decomposition.

	New Methods for Controller Design, Analysis and Validation in the Design of DC / DC Converters By Idris Gadoura; Kai Heikkinen; Kai Zenger; Petri Vallittu; Teuvo Suntio	[View] [Download]
Abstract: This paper presents a design procedure of a PIDcontroller, which regulates a buck converter operating in continuous-conduction mode with voltage-mode control and current-mode control. Matlab / Simulink and FuzzyTECH are used to design and tune a fuzzy PID controller. All models are validated in saberJ environment.