Parallel IGBT Switching for High-Power Motor Inverters
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Solution Overview
Problem
High-power electric motors require more efficient and cost-effective controllable rectification devices, as traditional low-power IGBTs limit torque and power, while high-power IGBTs increase costs and energy consumption.
Innovation Solution
A controllable rectification device with three switch element groups connected in parallel, where each group comprises two or more switch elements, allowing simultaneous conduction or breaking of upper and lower bridge-arm switches, enhancing current resistance and reducing the need for expensive high-power IGBTs, and incorporating Intelligent Power Modules for efficient switching.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If low-power IGBTs are used in the controllable rectification device, then the device complexity and cost are reduced, but the torque and power of the motor are limited
Solution Approach 1:
The patent divides each switch element into multiple parallel IGBTs (e.g., two IGBTs per switch element). This segmentation allows the system to achieve high current handling capability using multiple lower-power, lower-cost IGBTs instead of a single high-power IGBT, directly resolving the contradiction between cost and motor power.
2Power
If high-power IGBTs are used to increase motor power, then the torque and power capability are improved, but the cost increases rapidly and energy consumption increases
Solution Approach 1:
The patent segments high-power switching functionality into multiple parallel lower-power IGBTs. For example, each switch element comprises multiple IGBTs connected in parallel, allowing the system to achieve the required current handling capability through aggregation of multiple affordable components rather than using expensive high-power IGBTs.
Solution Approach 2:
The patent combines multiple parallel IGBTs within each switch element to function as a unified high-current switch. The control panel coordinates these parallel IGBTs to operate together, effectively merging their current handling capabilities to replace what would otherwise require a single high-power IGBT, thereby reducing cost while maintaining power output.
3Power
If high-power IGBTs are used to achieve high motor power, then the power capability is improved, but the power consumption of the IGBT increases leading to energy waste
Solution Approach 1:
The patent divides the high-power switching function into multiple parallel lower-power IGBTs. Lower-power IGBTs inherently consume less power during switching operations compared to a single high-power IGBT performing the same function, thus reducing overall energy loss while maintaining the required motor power output.
Data Source
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AI summary
A controllable inverter and an electric motor provided with the controllable inverter. The controllable inverter includes an inverter (10), a control panel (20) for generating a PWM waveform and a drive panel (30) for generating drive voltages for switching on or switching off the switches in the inverter (10) according to the PWM waveform. The inverter (10) includes three switch element groups connected in parallel. Each switch element group includes at least two switch elements (IGBT1, IGBT2, IGBT3, IGBT4, IGBT5, IGBT6) connected in parallel. Each switch element (IGBT1, IGBT2, IGBT3, IGBT4, IGBT5, IGBT6) includes an upper bridge-arm switch (IGBT1', IGBT2', IGBT3', IGBT4', IGBT5', IGBT6') and a lower bridge-arm switch (IGBT1'', IGBT2'', IGBT3'', IGBT4'', IGBT5'', IGBT6''). The lower bridge-arm switches (IGBT1'', IGBT2'', IGBT3'', IGBT4'', IGBT5'', IGBT6'') of the same switch element group are switched on and off simultaneously, and the upper bridge-arm switches (IGBT1', IGBT2', IGBT3', IGBT4', IGBT5', IGBT6') of the same switch element group are switched on and off simultaneously. The electric motor includes three phase windings (U, V, W). Each phase winding (U, V, W) includes at least two windings (U1, U2, V1, V2, W1, W2) connected in parallel.