Converter-Inverter Drive With Automatic Filter Detection
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Solution Overview
Problem
Existing drive systems for electric motors lack the ability to automatically detect the presence of filters and adapt their operation mode accordingly, leading to potential safety issues and inefficiencies in power conversion.
Innovation Solution
A drive system that includes a converter and inverter with signal lines connected to fixed potentials, allowing automatic detection of filter presence, enabling either sinusoidal or block-type operation based on the presence of network chokes and filters, and utilizing a slim intermediate circuit and regenerative rectifier for efficient power control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If automatic detection of filter presence is implemented, then operational safety is improved, but device complexity increases
Solution Approach 1:
The system automatically detects the presence or absence of the filter and autonomously selects the appropriate operating mode (sinusoidal or block-shaped) without requiring manual intervention or complex external control systems. The converter performs self-diagnosis by monitoring the voltage at its output terminal and self-adjusts its operation accordingly, eliminating the need for additional detection devices while ensuring operational safety.
2Measurement precision
If a variable-rate choke is used for sinusoidal feedback, then feedback precision is improved, but device complexity and cost increase
Solution Approach 1:
The system dynamically adapts its feedback method based on the detected operating conditions. Instead of using a complex variable-rate choke for all operations, the system employs sinusoidal feedback with phase-synchronous control when a filter is present, and switches to block-shaped feedback with voltage and current control when no filter is present. This dynamic adaptation eliminates the need for a variable-rate choke while maintaining feedback precision across different operating modes.
3Device complexity
If block-type operation is used without filter, then device simplicity is improved, but operational flexibility decreases
Solution Approach 1:
The converter is designed with universal capability to perform both sinusoidal feedback operation (when filter is present) and block-shaped feedback operation (when filter is absent). The system incorporates a detection mechanism that identifies the operating conditions and automatically selects the appropriate mode, making the single device adaptable to multiple operating scenarios without requiring separate specialized systems for each mode.
Data Source
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AI summary
The invention relates to a drive system comprising a converter, in particular an AC/DC converter, and an inverter for supplying power to an electric motor which is electrically connected to the AC voltage-side terminal of the inverter, wherein: the DC voltage-side terminal of the inverter is connected to the DC voltage-side terminal of the converter; a first means for detecting the voltage applied to the AC voltage-side terminal of the converter is connected to an input of a first analogue-to-digital converter of a signal electronics system by means of a first signal line; a second means for detecting a voltage, in particular a three-phase voltage, applied to a filter can be connected to an input of a second analogue-to-digital converter of the signal electronics system by means of a second signal line; the signal electronics system comprises an actuator for the semiconductor switch of the converter; the output of the first analogue-to-digital converter and the output of the second analogue-to-digital converter is connected to a comparison means of the signal electronics system; and a switching means of the signal electronics system adjusts the operating mode of the actuator of the semiconductor switches of the converter depending on the output signal of the comparison means.