Façade-integrated MVHR with speed-controlled micro-heat pump.

The majority of existing building stock in Europe and worldwide is poor energy performance buildings and renovation plays a major role in achieving climate protection and energy independence. Deep renovation solutions in combination with integrated HVAC systems are developed within the framework of the European project iNSPiRe. The development, testing and modelling of a façade integrated micro-heat pump (μ-HP) in combination with mechanical ventilation with heat recovery (MVHR) is presented. A detailed physical model of the μ-HP is developed within the Matlab simulation environment. The vapour cycle and the air heating/cooling are modelled in steady state to derive the thermodynamic states of the refrigerant and of the air. The refrigerant cycle and the governing equations for the moist air are solved iteratively. Two functional models (dimensions: 2.75 m x 2.75 m) were built for the tests in PASSYS test cells, which allow controlling the temperature with high-power heater and cooler. With a so-called cold box the external boundary conditions can be emulated. Experimental results are used to validate the physical heat pump and MVHR model. The physical model is used to create the performance map data for building and system simulation. Combined building and HVAC simulations are performed to investigate the energy performance of the μ-HP on building level. The performance of the system is investigated for different renovation standards (EnerPHit and Passive House) and for seven different European climate conditions. Different control strategies are investigated and a frosting model is used to optimize defrosting control and thus to reduce energy demand. A functional model will be later monitored in a demo building in Ludwigsburg, Germany. The example of social housing built in the 1970s contains four flats on four stories. The main advantages of the μ-HP are the compactness, providing the possibility of integration into the façade, and cost reduction.

欧洲及全球范围内的大部分现有建筑存量均为低能效建筑，而翻新改造在实现气候保护与能源独立方面发挥着关键作用。欧洲iNSPiRe项目框架内开发了深度翻新方案与集成暖通空调系统（HVAC）相结合的技术。本文介绍了与带热回收的机械通风系统（MVHR）相结合的 facade 集成微型热泵（μ-HP）的开发、测试与建模工作。在Matlab仿真环境中构建了μ-HP的详细物理模型。对蒸汽循环及空气加热/冷却过程进行稳态建模，以推导制冷剂与空气的热力学状态。制冷剂循环及湿空气控制方程采用迭代法求解。为在PASSYS测试单元中开展试验，构建了两个功能模型（尺寸：2.75 m × 2.75 m），该测试单元可通过大功率加热器与冷却器实现温度控制。通过所谓的冷箱可模拟外部边界条件。试验结果用于验证热泵物理模型与MVHR模型。该物理模型用于生成建筑及系统仿真所需的性能图谱数据。通过建筑与HVAC系统联合仿真，研究了μ-HP在建筑层面的能效表现。针对不同翻新标准（EnerPHit与被动式住宅）及七种欧洲气候条件，研究了系统性能。研究了多种控制策略，并采用结霜模型优化除霜控制，从而降低能耗需求。后续将在德国路德维希堡的示范建筑中对功能模型进行监测。该示范建筑为20世纪70年代建造的社会住宅，共四层四户。μ-HP的主要优势在于其紧凑性（可集成至 facade）及成本降低。